1
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Sano M, Kamei K, Yatsuhashi T, Sakota K. Localization and Orientation of Dye Molecules at the Surface of a Levitated Microdroplet in Air Revealed by Whispering Gallery Mode Resonances. J Phys Chem Lett 2024; 15:8133-8141. [PMID: 39087939 DOI: 10.1021/acs.jpclett.4c01819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/02/2024]
Abstract
Microdroplets offer unique environments that accelerate chemical reactions; however, the mechanisms behind these processes remain debated. The localization and orientation of solute molecules near the droplet surface have been proposed as factors for this acceleration. Since significant reaction acceleration has been observed for electrospray- and sonic-spray-generated aerosol droplets, the analysis of microdroplets in air has become essential. Here, we utilized whispering gallery mode (WGM) resonances to investigate the localization and orientation of dissolved rhodamine B (RhB) in a levitated microdroplet (∼3 μm in diameter) in air. Fluorescence enhancement upon resonance with the WGMs revealed the localization and orientation of RhB near the droplet surface. Numerical modeling using Mie theory quantified the RhB orientation at 68° to the surface normal, with a small fraction randomly oriented inside the droplet. Additionally, low RhB concentrations increased surface localization. These results support the significance of surface reactions in the acceleration of microdroplet reactions.
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Affiliation(s)
- Motoya Sano
- Division of Molecular Material Science, Graduate School of Science, Osaka City University, 3-3-138, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Kota Kamei
- Division of Molecular Material Science, Graduate School of Science, Osaka City University, 3-3-138, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Tomoyuki Yatsuhashi
- Department of Chemistry, Graduate School of Science, Osaka Metropolitan University, 3-3-138, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
| | - Kenji Sakota
- Department of Chemistry, Graduate School of Science, Osaka Metropolitan University, 3-3-138, Sugimoto, Sumiyoshi-ku, Osaka 558-8585, Japan
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2
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Feng Y, Morato NM, Huang KH, Lin M, Cooks RG. High-throughput label-free opioid receptor binding assays using an automated desorption electrospray ionization mass spectrometry platform. Chem Commun (Camb) 2024; 60:8224-8227. [PMID: 39007214 PMCID: PMC11293027 DOI: 10.1039/d4cc02346c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2024] [Accepted: 07/09/2024] [Indexed: 07/16/2024]
Abstract
The current opioid epidemic has incentivized the discovery of new non-addictive analgesics, a process that requires the screening of opioid receptor binding, traditionally performed using radiometric assays. Here we describe a label-free alternative based on high-throughput (1 Hz) ambient mass spectrometry for screening the receptor binding of new opioid analogues.
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Affiliation(s)
- Yunfei Feng
- Department of Chemistry, Bindley Bioscience Center, and Purdue Institute for Cancer Research, Purdue University, West Lafayette, IN 47907, USA.
| | - Nicolás M Morato
- Department of Chemistry, Bindley Bioscience Center, and Purdue Institute for Cancer Research, Purdue University, West Lafayette, IN 47907, USA.
| | - Kai-Hung Huang
- Department of Chemistry, Bindley Bioscience Center, and Purdue Institute for Cancer Research, Purdue University, West Lafayette, IN 47907, USA.
| | - Mina Lin
- Department of Chemistry, Bindley Bioscience Center, and Purdue Institute for Cancer Research, Purdue University, West Lafayette, IN 47907, USA.
| | - R Graham Cooks
- Department of Chemistry, Bindley Bioscience Center, and Purdue Institute for Cancer Research, Purdue University, West Lafayette, IN 47907, USA.
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3
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Li Y, Ding J, Qin W. Enhanced Selectivity in Microdroplet-Mediated Enzyme Catalysis. J Am Chem Soc 2024. [PMID: 39073863 DOI: 10.1021/jacs.4c06171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Natural enzymes with enhanced catalytic activity and selectivity have long been studied by tuning the microenvironment around the active site, but how to modulate the active-site electric field in a simple fashion remains challenging. Here, we demonstrate that microdroplets as a simple yet versatile reactor can enhance the electric field at the active site of an enzyme. By using horseradish peroxidase as a model, improved selectivity in microdroplet-mediated enzyme catalysis can be obtained. Quantum mechanical/molecular dynamics calculations and vibrational Stark spectroscopy reveal that the electric field at the microdroplet interface can influence the electrostatic preorganization and orientation of the enzyme to enhance its internal electric field. As a result, the free energies of the substrate and heme can be tuned by the internal electric field, thereby changing its catalytic reaction pathway for a classical substrate, 3,3',5,5'-tetramethylbenzidine, and enabling selective C-N additions for specific substrates. This finding provides a green, simple, and effective way to modulate enzyme-catalyzed reactions and holds promise for a broad spectrum of biosensing and biosynthesis applications.
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Affiliation(s)
- Yinhao Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jiawang Ding
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Wei Qin
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, P. R. China
- Laboratory for Marine Biology and Biotechnology, Qingdao Marine Science and Technology Center, Qingdao, Shandong 266237, P. R. China
- Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, Shandong 266071, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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4
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Zhang P, Feng M, Xu X. Double-Layer Distribution of Hydronium and Hydroxide Ions in the Air-Water Interface. ACS PHYSICAL CHEMISTRY AU 2024; 4:336-346. [PMID: 39069983 PMCID: PMC11274287 DOI: 10.1021/acsphyschemau.3c00076] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 04/04/2024] [Accepted: 04/05/2024] [Indexed: 07/30/2024]
Abstract
The acid-base nature of the aqueous interface has long been controversial. Most macroscopic experiments suggest that the air-water interface is basic based on the detection of negative charges at the interface that indicates the enrichment of hydroxides (OH-), whereas microscopic studies mostly support the acidic air-water interface with the observation of hydronium (H3O+) accumulation in the top layer of the interface. It is crucial to clarify the interfacial preference of OH- and H3O+ ions for rationalizing the debate. In this work, we perform deep potential molecular dynamics simulations to investigate the preferential distribution of OH- and H3O+ ions at the aqueous interfaces. The neural network potential energy surface is trained based on density functional theory calculations with the SCAN functional, which can accurately describe the diffusion of these two ions both in the interface and in the bulk water. In contrast to the previously reported single ion enrichment, we show that both OH- and H3O+ surprisingly prefer to accumulate in interfaces but at different interfacial depths, rendering a double-layer ionic distribution within ∼1 nm near the Gibbs dividing surface. The H3O+ preferentially resides in the topmost layer of the interface, but the OH-, which is enriched in the deeper interfacial layer, has a higher equilibrium concentration due to the more negative free energy of interfacial stabilization [-0.90 (OH-) vs -0.56 (H3O+) kcal/mol]. The present finding of the ionic double-layer distribution may qualitatively offer a self-consistent explanation for the long-term controversy about the acid-base nature of the air-water interface.
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Affiliation(s)
- Pengchao Zhang
- Center
for Combustion Energy, Department of Energy and Power Engineering,
and Key Laboratory for Thermal Science and Power Engineering of Ministry
of Education, Tsinghua University, Beijing 100084, China
| | - Muye Feng
- School
of Mechanical and Power Engineering, Nanjing
Tech University, Nanjing 211816, China
| | - Xuefei Xu
- Center
for Combustion Energy, Department of Energy and Power Engineering,
and Key Laboratory for Thermal Science and Power Engineering of Ministry
of Education, Tsinghua University, Beijing 100084, China
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5
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Lee K, Cho Y, Kim JC, Choi C, Kim J, Lee JK, Li S, Kwak SK, Choi SQ. Catalyst-free selective oxidation of C(sp 3)-H bonds in toluene on water. Nat Commun 2024; 15:6127. [PMID: 39033208 PMCID: PMC11271591 DOI: 10.1038/s41467-024-50352-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 07/08/2024] [Indexed: 07/23/2024] Open
Abstract
The anisotropic water interfaces provide an environment to drive various chemical reactions not seen in bulk solutions. However, catalytic reactions by the aqueous interfaces are still in their infancy, with the emphasis being on the reaction rate acceleration on water. Here, we report that the oil-water interface activates and oxidizes C(sp3)-H bonds in toluene, yielding benzaldehyde with high selectivity (>99%) and conversion (>99%) under mild, catalyst-free conditions. Collision at the interface between oil-dissolved toluene and hydroxyl radicals spontaneously generated near the water-side interfaces is responsible for the unexpectedly high selectivity. Protrusion of free OH groups from interfacial water destabilizes the transition state of the OH-addition by forming π-hydrogen bonds with toluene, while the H-abstraction remains unchanged to effectively activate C(sp3)-H bonds. Moreover, the exposed free OH groups form hydrogen bonds with the produced benzaldehyde, suppressing it from being overoxidized. Our investigation shows that the oil-water interface has considerable promise for chemoselective redox reactions on water without any catalysts.
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Affiliation(s)
- Kyoungmun Lee
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Yumi Cho
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), UNIST-gil 50, Ulju-gun, Ulsan, Republic of Korea
| | - Jin Chul Kim
- School of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST), UNIST-gil 50, Ulju-gun, Ulsan, Republic of Korea
| | - Chiyoung Choi
- Department of Applied Bioengineering, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, Republic of Korea
| | - Jiwon Kim
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
| | - Jae Kyoo Lee
- Department of Applied Bioengineering, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, Republic of Korea
- Research Institute for Convergence Science, Seoul National University, Seoul, Republic of Korea
| | - Sheng Li
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea
- KAIST Institute for the Nanocentury, KAIST, Daejeon, Republic of Korea
| | - Sang Kyu Kwak
- Department of Chemical and Biological Engineering, Korea University, Seoul, Republic of Korea.
| | - Siyoung Q Choi
- Department of Chemical and Biomolecular Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.
- KAIST Institute for the Nanocentury, KAIST, Daejeon, Republic of Korea.
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6
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Torre MF, Amadeo A, Cassone G, Tommasini M, Mráziková K, Saija F. Water Dimer under Electric Fields: An Ab Initio Investigation up to Quantum Accuracy. J Phys Chem A 2024; 128:5490-5499. [PMID: 38976361 DOI: 10.1021/acs.jpca.4c01553] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
It is well-established that strong electric fields (EFs) can align water dipoles, partially order the H-bond network of liquid water, and induce water splitting and proton transfers. To illuminate the fundamental behavior of water under external EFs, we present the first benchmark, to the best of our knowledge, of DFT calculations of the water dimer exposed to intense EFs against coupled cluster calculations. The analyses of the vibrational Stark effect and electron density provide a consistent picture of the intermolecular charge transfer effects driven along the H-bond by the increasing applied field at all theory levels. However, our findings prove that at extreme field regimes (∼1-2 V/Å) DFT calculations significantly exaggerate by ∼10-30% the field-induced strengthening of the H-bond, both within the GGA, hybrid GGA, and hybrid meta-GGA approximations. Notably, a linear correlation emerges between the vibrational Stark effect on OH stretching and H-bond strengthening: a 1 kcal mol-1 increase corresponds to an 80 cm-1 red-shift in OH stretching frequency.
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Affiliation(s)
- Marco Francesco Torre
- Department of Chemical, Biological, Pharmaceutical and Environmental Science, University of Messina, 98166 Messina, Italy
| | - Alessandro Amadeo
- Department of Chemical, Biological, Pharmaceutical and Environmental Science, University of Messina, 98166 Messina, Italy
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Giuseppe Cassone
- Institute for Chemical-Physical Processes, National Research Council of Italy (IPCF-CNR), 98158 Messina, Italy
| | - Matteo Tommasini
- Dipartimento di Chimica, Materiali e Ing. Chimica "G. Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Klaudia Mráziková
- J. Heyrovský Institute of Physical Chemistry, Czech Academy of Sciences, Dolejškova 3, 18223 Prague, Czechia
| | - Franz Saija
- Institute for Chemical-Physical Processes, National Research Council of Italy (IPCF-CNR), 98158 Messina, Italy
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7
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Xia Y, Xu J, Li J, Chen B, Dai Y, Zare RN. Visualization of the Charging of Water Droplets Sprayed into Air. J Phys Chem A 2024; 128:5684-5690. [PMID: 38968601 DOI: 10.1021/acs.jpca.4c02981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/07/2024]
Abstract
Water droplets are spraying into air using air as a nebulizing gas, and the droplets pass between two parallel metal plates with opposite charges. A high-speed camera records droplet trajectories in the uniform electric field, providing visual evidence for the Lenard effect, that is, smaller droplets are negatively charged whereas larger droplets are positively charged. By analyzing the velocities of the droplets between the metal plates, the charges on the droplets can be estimated. Some key observations include: (1) localized electric fields with intensities on the order of 109 V/m are generated, and charges are expected to jump (micro-lightening) between a positively charged larger droplet and the negatively charged smaller droplet as they separate; (2) the strength of the electric field is sufficiently powerful to ionize gases surrounding the droplets; and (3) observations in an open-air mass spectrometer reveal the presence of ions such as N2+, O2+, NO+, and NO2+. These findings provide new insight into the origins of some atmospheric ions and have implications for understanding ionization processes in the atmosphere and chemical transformations in water droplets, advancing knowledge in the field of aerosol science and water microdroplet chemistry.
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Affiliation(s)
- Yu Xia
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, P. R. China
| | - Jinheng Xu
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Juan Li
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, P. R. China
| | - Bolei Chen
- Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances, School of Environment and Health, Jianghan University, Wuhan 430056, P. R. China
| | - Yifan Dai
- Department of Biomedical Engineering, Center for Biomolecular Condensates, Washington University in St. Louis, Saint Louis, Missouri 63130, United States
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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8
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Guo X, Farag M, Qian N, Yu X, Ni A, Ma Y, Yu W, King MR, Liu V, Lee J, Zare RN, Min W, Pappu RV, Dai Y. Biomolecular condensates can function as inherent catalysts. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.06.602359. [PMID: 39026887 PMCID: PMC11257451 DOI: 10.1101/2024.07.06.602359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
We report the discovery that chemical reactions such as ATP hydrolysis can be catalyzed by condensates formed by intrinsically disordered proteins (IDPs), which themselves lack any intrinsic ability to function as enzymes. This inherent catalytic feature of condensates derives from the electrochemical environments and the electric fields at interfaces that are direct consequences of phase separation. The condensates we studied were capable of catalyzing diverse hydrolysis reactions, including hydrolysis and radical-dependent breakdown of ATP whereby ATP fully decomposes to adenine and multiple carbohydrates. This distinguishes condensates from naturally occurring ATPases, which can only catalyze the dephosphorylation of ATP. Interphase and interfacial properties of condensates can be tuned via sequence design, thus enabling control over catalysis through sequence-dependent electrochemical features of condensates. Incorporation of hydrolase-like synthetic condensates into live cells enables activation of transcriptional circuits that depend on products of hydrolysis reactions. Inherent catalytic functions of condensates, which are emergent consequences of phase separation, are likely to affect metabolic regulation in cells.
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Affiliation(s)
- Xiao Guo
- Department of Biomedical Engineering, Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO 63130
| | - Mina Farag
- Department of Biomedical Engineering, Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO 63130
| | - Naixin Qian
- Department of Chemistry, Columbia University, New York, NY 10027
| | - Xia Yu
- Department of Chemistry, Stanford University, Stanford, CA 94305
| | - Anton Ni
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138
| | - Yuefeng Ma
- Department of Biomedical Engineering, Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO 63130
| | - Wen Yu
- Department of Biomedical Engineering, Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO 63130
| | - Matthew R. King
- Department of Biomedical Engineering, Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO 63130
| | - Vicky Liu
- Department of Biomedical Engineering, Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO 63130
| | - Joonho Lee
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138
| | - Richard N. Zare
- Department of Chemistry, Stanford University, Stanford, CA 94305
| | - Wei Min
- Department of Chemistry, Columbia University, New York, NY 10027
| | - Rohit V. Pappu
- Department of Biomedical Engineering, Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO 63130
| | - Yifan Dai
- Department of Biomedical Engineering, Center for Biomolecular Condensates, Washington University in St. Louis, St. Louis, MO 63130
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9
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Mofidfar M, Mehrgardi MA, Zare RN. Water Microdroplets Surrounded by Alcohol Vapor Cause Spontaneous Oxidation of Alcohols to Organic Peroxides. J Am Chem Soc 2024; 146:18498-18503. [PMID: 38935892 DOI: 10.1021/jacs.4c04092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2024]
Abstract
Using real-time mass spectrometric (MS) monitoring, we demonstrate one-step, catalyst-free spontaneous oxidation of various alcohols (ROH) to key reactive intermediates for the formation of ROO- compounds on the surface of water microdroplets surrounded by alcohol vapor, carried out under ambient conditions. These organic peroxides (POs) can act as important secondary organic aerosols (SOA). We used hydrogen-deuterium exchange by spraying D2O instead of H2O to learn about the reaction mechanism, and the results demonstrate the crucial role of the water-air interface in microdroplet chemistry. We find that the formation of POs relies on electron transfer occurring at the microdroplet interface, which generates hydrogen atoms and hydroxyl radicals that lead to a cascade of radical reactions. This electron transfer is believed to be driven by two factors: (1) the emergence of a strong electrostatic potential on the microdroplet's surface; and (2) the partial solvation of ions at the interface. Mass spectra reveal that the formation of POs is dependent on the alcohol structure, with tertiary alcohols showing a higher tendency to form organic peroxides than secondary alcohols, which in turn are more reactive than primary alcohols.
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Affiliation(s)
- Mohammad Mofidfar
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | | | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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10
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Kumar A, Avadhani VS, Nandy A, Mondal S, Pathak B, Pavuluri VKN, Avulapati MM, Banerjee S. Water Microdroplets in Air: A Hitherto Unnoticed Natural Source of Nitrogen Oxides. Anal Chem 2024; 96:10515-10523. [PMID: 38829716 DOI: 10.1021/acs.analchem.4c00371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
Water microdroplets are widespread in the atmosphere. We report a striking observation that micron-sized water droplets obtained from zero-volt spray sources (sonic spray, humidifier, spray bottle, steamer, etc.) spontaneously generate nitrogen oxides. The mechanistic investigation through the development of custom-designed sampling sources combined with mass spectrometry and isotope labeling experiments confirmed that air nitrogen reacts with the water at the air-water interface, fixing molecular nitrogen to its oxides (NO, NO2, and N2O) and acids (HNO2 and HNO3) at trace levels without any catalyst. These reactions are attributed to the consequence of an experimentally detected feeble corona discharge (breakdown of air) at the air-water interface, likely driven by the high intrinsic electric field at the surface of water microdroplets. The extent of this corona discharge effect varies depending on the pH, salinity/impurity, size, speed, and lifetime of microdroplets in the air. Thus, this study discloses that the air-water interface of microdroplets breaks the strong chemical bond of nitrogen (N2), producing nitrogen oxides in the environment, while lightning strikes and microbial processes in soil are considered their dominant natural sources. As nitrogen oxides are toxic air pollutants, their spontaneous formation at the air-water interface should have important implications in atmospheric reactions, requiring further investigations.
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Affiliation(s)
- Anubhav Kumar
- Department of Chemistry, Indian Institute of Science Education and Research Tirupati, Tirupati 517507, India
| | - Veena Shankar Avadhani
- Department of Chemistry, Indian Institute of Science Education and Research Tirupati, Tirupati 517507, India
| | - Abhijit Nandy
- Department of Chemistry, Indian Institute of Science Education and Research Tirupati, Tirupati 517507, India
| | - Supratim Mondal
- Department of Chemistry, Indian Institute of Science Education and Research Tirupati, Tirupati 517507, India
| | - Barsha Pathak
- Department of Chemistry, Indian Institute of Science Education and Research Tirupati, Tirupati 517507, India
| | | | - Madan Mohan Avulapati
- Department of Mechanical Engineering, Indian Institute of Technology Tirupati, Tirupati 517619, India
| | - Shibdas Banerjee
- Department of Chemistry, Indian Institute of Science Education and Research Tirupati, Tirupati 517507, India
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11
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Vannoy KJ, Edwards MQ, Renault C, Dick JE. An Electrochemical Perspective on Reaction Acceleration in Microdroplets. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2024; 17:149-171. [PMID: 38594942 DOI: 10.1146/annurev-anchem-061622-030919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Analytical techniques operating at the nanoscale introduce confinement as a tool at our disposal. This review delves into the phenomenon of accelerated reactivity within micro- and nanodroplets. A decade of accelerated reactivity observations was succeeded by several years of fundamental studies aimed at mechanistic enlightenment. Herein, we provide a brief historical context for rate enhancement in and around micro- and nanodroplets and summarize the mechanisms that have been proposed to contribute to such extraordinary reactivity. We highlight recent electrochemical reports that make use of restricted mass transfer to enhance electrochemical reactions and/or quantitatively measure reaction rates within droplet-confined electrochemical cells. A comprehensive approach to nanodroplet reactivity is paramount to understanding how nature takes advantage of these systems to provide life on Earth and, in turn, how to harness the full potential of such systems.
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Affiliation(s)
- Kathryn J Vannoy
- 1Department of Chemistry, Purdue University, West Lafayette, Indiana, USA;
| | | | - Christophe Renault
- 1Department of Chemistry, Purdue University, West Lafayette, Indiana, USA;
- 2Current Address: Department of Chemistry and Biochemistry, Loyola University Chicago, Chicago, Illinois, USA
| | - Jeffrey E Dick
- 1Department of Chemistry, Purdue University, West Lafayette, Indiana, USA;
- 3Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, Indiana, USA
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12
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de la Puente M, Laage D. Impact of interfacial curvature on molecular properties of aqueous interfaces. J Chem Phys 2024; 160:234504. [PMID: 38888129 DOI: 10.1063/5.0210884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 05/28/2024] [Indexed: 06/20/2024] Open
Abstract
The curvature of soft interfaces plays a crucial role in determining their mechanical and thermodynamic properties, both at macroscopic and microscopic scales. In the case of air/water interfaces, particular attention has recently focused on water microdroplets, due to their distinctive chemical reactivity. However, the specific impact of curvature on the molecular properties of interfacial water and interfacial reactivity has so far remained elusive. Here, we use molecular dynamics simulations to determine the effect of curvature on a broad range of structural, dynamical, and thermodynamical properties of the interface. For a droplet, a flat interface, and a cavity, we successively examine the structure of the hydrogen-bond network and its relation to vibrational spectroscopy, the dynamics of water translation, rotation, and hydrogen-bond exchanges, and the thermodynamics of ion solvation and ion-pair dissociation. Our simulations show that curvature predominantly impacts the hydrogen-bond structure through the fraction of dangling OH groups and the dynamics of interfacial water molecules. In contrast, curvature has a limited effect on solvation and ion-pair dissociation thermodynamics. For water microdroplets, this suggests that the curvature alone cannot fully account for the distinctive reactivity measured in these systems, which are of great importance for catalysis and atmospheric chemistry.
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Affiliation(s)
- M de la Puente
- PASTEUR, Department of Chemistry, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
| | - D Laage
- PASTEUR, Department of Chemistry, École Normale Supérieure, PSL University, Sorbonne Université, CNRS, 75005 Paris, France
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13
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Yuan G, Jin Z, Cao Y, Schulz HM, Gluyas J, Liu K, He X, Wang Y. Microdroplets initiate organic-inorganic interactions and mass transfer in thermal hydrous geosystems. Nat Commun 2024; 15:4960. [PMID: 38862499 PMCID: PMC11167059 DOI: 10.1038/s41467-024-49293-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Accepted: 05/22/2024] [Indexed: 06/13/2024] Open
Abstract
Organic-inorganic interactions regulate the dynamics of hydrocarbons, water, minerals, CO2, and H2 in thermal rocks, yet their initiation remains debated. To address this, we conducted isotope-tagged and in-situ visual thermal experiments. Isotope-tagged studies revealed extensive H/O transfers in hydrous n-C20H42-H2O-feldspar systems. Visual experiments observed water microdroplets forming at 150-165 °C in oil phases near the water-oil interface without surfactants, persisting until complete miscibility above 350 °C. Electron paramagnetic resonance (EPR) detected hydroxyl free radicals concurrent with microdroplet formation. Here we propose a two-fold mechanism: water-derived and n-C20H42-derived free radicals drive interactions with organic species, while water-derived and mineral-derived ions trigger mineral interactions. These processes, facilitated by microdroplets and bulk water, blur boundaries between organic and inorganic species, enabling extensive interactions and mass transfer. Our findings redefine microscopic interplays between organic and inorganic components, offering insights into diagenetic and hydrous-metamorphic processes, and mass transfer cycles in deep basins and subduction zones.
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Affiliation(s)
- Guanghui Yuan
- State Key Laboratory of Deep Oil and Gas, China University of Petroleum (East China), Qingdao, P.R. China.
- Institute of Energy, School of Earth and Space Sciences, Peking University, Beijing, P.R. China.
| | - Zihao Jin
- State Key Laboratory of Deep Oil and Gas, China University of Petroleum (East China), Qingdao, P.R. China
| | - Yingchang Cao
- State Key Laboratory of Deep Oil and Gas, China University of Petroleum (East China), Qingdao, P.R. China.
| | - Hans-Martin Schulz
- GFZ German Research Centre for Geosciences, Telegrafenberg, Potsdam, Germany
| | - Jon Gluyas
- Department of Earth Sciences, Durham University, Durham, UK
| | - Keyu Liu
- State Key Laboratory of Deep Oil and Gas, China University of Petroleum (East China), Qingdao, P.R. China
| | - Xingliang He
- Qingdao Institute of Marine Geology, China Geological Survey, Qingdao, China
| | - Yanzhong Wang
- State Key Laboratory of Deep Oil and Gas, China University of Petroleum (East China), Qingdao, P.R. China
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14
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Judd KD, Parsons SW, Eremin DB, Fokin VV, Dawlaty JM. Visualizing partial solvation at the air-water interface. Chem Sci 2024; 15:8346-8354. [PMID: 38846382 PMCID: PMC11151832 DOI: 10.1039/d4sc01311e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Accepted: 04/08/2024] [Indexed: 06/09/2024] Open
Abstract
Despite significant research, the mechanistic nuances of unusual reactivity at the air-water interface, especially in microdroplets, remain elusive. The likely contributors include electric fields and partial solvation at the interface. To reveal these intricacies, we measure the frequency shift of a well-defined azide vibrational probe at the air-water interface, while independently controlling the surface charge density by introducing surfactants. First, we establish the response of the probe in the bulk and demonstrate that it is sensitive to both electrostatics and hydrogen bonding. From interfacial spectroscopy we infer that the azide is neither fully hydrated nor in a completely aprotic dielectric environment; instead, it experiences an intermediate environment. In the presence of hydrogen bond-accepting sulphate surfactants, competition arises for interfacial water with the azide. However, the dominant influence stems from the electrostatic effect of their negative heads, resulting in a significant blue-shift. Conversely, for the positive ammonium surfactants, our data indicate a balanced interplay between electrostatics and hydrogen bonding, leading to a minimal shift in the probe. Our results demonstrate partial solvation at the interface and highlights that both hydrogen bonding and electrostatics may assist or oppose each other in polarizing a reactant, intermediate, or product at the interface, which is important for understanding and tuning interfacial reactivity.
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Affiliation(s)
- Kenneth D Judd
- Department of Chemistry, The University of Southern California Los Angeles CA 90089 USA
| | - Sean W Parsons
- Department of Chemistry, The University of Southern California Los Angeles CA 90089 USA
| | - Dmitry B Eremin
- Department of Chemistry, The University of Southern California Los Angeles CA 90089 USA
| | - Valery V Fokin
- Department of Chemistry, The University of Southern California Los Angeles CA 90089 USA
| | - Jahan M Dawlaty
- Department of Chemistry, The University of Southern California Los Angeles CA 90089 USA
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15
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Wilson KR, Prophet AM. Chemical Kinetics in Microdroplets. Annu Rev Phys Chem 2024; 75:185-208. [PMID: 38382571 DOI: 10.1146/annurev-physchem-052623-120718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
Micrometer-sized compartments play significant roles in driving heterogeneous transformations within atmospheric and biochemical systems as well as providing vehicles for drug delivery and novel reaction environments for the synthesis of industrial chemicals. Many reports now indicate that reaction kinetics are accelerated under microconfinement, for example, in sprays, thin films, droplets, aerosols, and emulsions. These observations are dramatic, posing a challenge to our understanding of chemical reaction mechanisms with potentially significant practical consequences for predicting the complex chemistry in natural systems. Here we introduce the idea of kinetic confinement, which is intended to provide a conceptual backdrop for understanding when and why microdroplet reaction kinetics differ from their macroscale analogs.
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Affiliation(s)
- Kevin R Wilson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA;
| | - Alexander M Prophet
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA;
- Department of Chemistry, University of California, Berkeley, California, USA;
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16
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Wang K, Pera-Titus M. Microstructured gas-liquid-(solid) interfaces: A platform for sustainable synthesis of commodity chemicals. SCIENCE ADVANCES 2024; 10:eado5448. [PMID: 38809985 PMCID: PMC11135396 DOI: 10.1126/sciadv.ado5448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Accepted: 04/25/2024] [Indexed: 05/31/2024]
Abstract
Gas-liquid-solid catalytic reactions are widespread in nature and man-made technologies. Recently, the exceptional reactivity observed on (electro)sprayed microdroplets, in comparison to bulk gas-liquid systems, has attracted the attention of researchers. In this perspective, we compile possible strategies to engineer catalytically active gas-liquid-(solid) interfaces based on membrane contactors, microdroplets, micromarbles, microbubbles, and microfoams to produce commodity chemicals such as hydrogen peroxide, ammonia, and formic acid. In particular, particle-stabilized microfoams, with superior upscaling capacity, emerge as a promising and versatile platform to conceive high-performing (catalytic) gas-liquid-(solid) nanoreactors. Gas-liquid-(solid) nanoreactors could circumvent current limitations of state-of-the-art multiphase reactors (e.g., stirred tanks, trickle beds, and bubble columns) suffering from poor gas solubility and mass transfer resistances and access gas-liquid-(solid) reactors with lower cost and carbon footprint.
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Affiliation(s)
- Kang Wang
- Cardiff Catalysis Institute, Cardiff University, Cardiff CF10 3AT, UK
| | - Marc Pera-Titus
- Cardiff Catalysis Institute, Cardiff University, Cardiff CF10 3AT, UK
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17
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Shaik S. My Vision of Electric-Field-Aided Chemistry in 2050. ACS PHYSICAL CHEMISTRY AU 2024; 4:191-201. [PMID: 38800723 PMCID: PMC11117677 DOI: 10.1021/acsphyschemau.3c00064] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 01/06/2024] [Accepted: 01/09/2024] [Indexed: 05/29/2024]
Abstract
This manuscript outlines my outlook on the development of electric-field (EF)-mediated-chemistry and the vision of its state by 2050. I discuss applications of oriented-external electric-fields (OEEFs) on chemical reactions and proceed with relevant experimental verifications. Subsequently, the Perspective outlines other ways of generating EFs, e.g., by use of pH-switchable charges, ionic additives, water droplets, and so on. A special section summarizes conceptual principles for understanding and predicting OEEF effects, e.g., the "reaction-axis rule", the capability of OEEFs to act as tweezers that orient reactants and accelerate their reaction, etc. Finally, I discuss applications of OEEFs in continuous-flow setups, which may, in principle, scale-up to molar concentrations. The Perspective ends with the vision that by 2050, OEEF usage will change chemical education, if not also the art of making new molecules.
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Affiliation(s)
- Sason Shaik
- Institute of Chemistry, The
Hebrew University of Jerusalem, Jerusalem 9190401, Israel
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18
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Voci S, Vannoy KJ, Dick JE. Femtoliter oil droplets act as CO 2 micropumps for uninterrupted electrochemiluminescence at the water|oil interface. J Colloid Interface Sci 2024; 661:853-860. [PMID: 38330657 PMCID: PMC11307245 DOI: 10.1016/j.jcis.2024.01.100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 01/04/2024] [Accepted: 01/14/2024] [Indexed: 02/10/2024]
Abstract
Interfacial effects are well-known to significantly alter chemical reactivity, especially in confined environments, where the surface to volume ratio increases. Here, we observed an inhomogeneity in the electrogenerated chemiluminescence (ECL) intensity decrease over time in a multiphasic system composed of femtoliter water droplets entrapping femtoliter volumes of the 1,2-dichloroethane (DCE) continuous phase. In usual electrochemiluminescence (ECL) reactions involving an ECL chromophore and oxalate ([C2O4]2-), the build-up of CO2 diminishes the ECL signal with time because of bubble formation. We hypothesised that relative solubilities of chemical species in these environments play a dramatic role in interfacial reactivity. Water droplets, loaded with the ECL luminophore [Ru(bpy)3]2+ and the coreactant [C2O4]2- were allowed to stochastically collide and adsorb at the surface of a glassy carbon macroelectrode. When water droplets coalesce on the surface, they leave behind femtoliter droplets of the DCE phase (inclusions). We report the surprising finding that the addition of multiple interfaces, due to the presence of continuous phase's femtoliter inclusions, allows sustained ECL over time after successive potential applications at the triple-phase boundary between water droplet|electrode|DCE inclusion. When femtoliter droplets of DCE form on the electrode surface, bright rings of ECL are observed during the simultaneous oxidation of [Ru(bpy)3]2+ and [C2O4]2-. Control experiments and finite element modelling allowed us to propose that these rings arise because CO2 that is generated near the 1,2-dichloroethane droplet partitions in due to relative solubility of CO2 in 1,2-dichloroethane and builds up and/or is expelled at the top of the droplet. The small droplets of the DCE phase act as micropumps, pumping away carbon dioxide from the interface. These results highlight the unexpected point that confined microenvironments and their geometry can tune chemical reactions of industrial importance and fundamental interest.
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Affiliation(s)
- Silvia Voci
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA
| | - Kathryn J Vannoy
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA
| | - Jeffrey E Dick
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA; Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN 47907, USA.
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19
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Heindel JP, LaCour RA, Head-Gordon T. The role of charge in microdroplet redox chemistry. Nat Commun 2024; 15:3670. [PMID: 38693110 DOI: 10.1038/s41467-024-47879-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Accepted: 04/12/2024] [Indexed: 05/03/2024] Open
Abstract
In charged water microdroplets, which occur in nature or in the lab upon ultrasonication or in electrospray processes, the thermodynamics for reactive chemistry can be dramatically altered relative to the bulk phase. Here, we provide a theoretical basis for the observation of accelerated chemistry by simulating water droplets of increasing charge imbalance to create redox agents such as hydroxyl and hydrogen radicals and solvated electrons. We compute the hydration enthalpy of OH- and H+ that controls the electron transfer process, and the corresponding changes in vertical ionization energy and vertical electron affinity of the ions, to create OH• and H• reactive species. We find that at ~ 20 - 50% of the Rayleigh limit of droplet charge the hydration enthalpy of both OH- and H+ have decreased by >50 kcal/mol such that electron transfer becomes thermodynamically favorable, in correspondence with the more favorable vertical electron affinity of H+ and the lowered vertical ionization energy of OH-. We provide scaling arguments that show that the nanoscale calculations and conclusions extend to the experimental microdroplet length scale. The relevance of the droplet charge for chemical reactivity is illustrated for the formation of H2O2, and has clear implications for other redox reactions observed to occur with enhanced rates in microdroplets.
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Affiliation(s)
- Joseph P Heindel
- Kenneth S. Pitzer Theory Center and Department of Chemistry, Berkeley, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - R Allen LaCour
- Kenneth S. Pitzer Theory Center and Department of Chemistry, Berkeley, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Teresa Head-Gordon
- Kenneth S. Pitzer Theory Center and Department of Chemistry, Berkeley, CA, USA.
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- Departments of Bioengineering and Chemical and Biomolecular Engineering University of CAlifornia, Berkeley, CA, USA.
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20
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Garavagno MDLA, Hernández FJ, Jara-Toro RA, Pino GA. Understanding the active role of water in laboratory chamber studies of reactions of the OH radical with alcohols of atmospheric relevance. Phys Chem Chem Phys 2024; 26:12745-12752. [PMID: 38619305 DOI: 10.1039/d3cp05667h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/16/2024]
Abstract
In this work, we studied the reactions of three cyclic aliphatic alcohols with OH at room temperature, atmospheric pressure and different humidities in a Teflon reaction chamber. It was determined that the lower the solubility of the alcohol in water, the larger the effect of the humidity on the acceleration of the reaction. This experimental evidence allows suggesting that the acceleration is due to the reaction of the co-adsorbed reactants at the air-water interface of a thin water film deposited on the Teflon walls of the reaction chamber, instead of between co-reactants dissolved in the water film or due to gas phase catalysis as previously suggested. Therefore, formation of thin water films on different surfaces could have some implications on the tropospheric chemistry of these alcohols in the tropical regions of the planet with high humidity.
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Affiliation(s)
- María de Los A Garavagno
- INFIQC: Instituto de Investigaciones en Físico-Química de Córdoba (CONICET - UNC), Haya de la Torre y Medina Allende, Pabellón Argentina, Ciudad Universitaria, Córdoba 5000, Argentina.
- Departamento de Fisicoquímica, Fac. de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Pabellón Argentina, Ciudad Universitaria, Córdoba 5000, Argentina
- Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Pabellón Argentina, Ciudad Universitaria, Córdoba 5000, Argentina
| | - Federico J Hernández
- INFIQC: Instituto de Investigaciones en Físico-Química de Córdoba (CONICET - UNC), Haya de la Torre y Medina Allende, Pabellón Argentina, Ciudad Universitaria, Córdoba 5000, Argentina.
- Departamento de Fisicoquímica, Fac. de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Pabellón Argentina, Ciudad Universitaria, Córdoba 5000, Argentina
- Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Pabellón Argentina, Ciudad Universitaria, Córdoba 5000, Argentina
| | - Rafael A Jara-Toro
- INFIQC: Instituto de Investigaciones en Físico-Química de Córdoba (CONICET - UNC), Haya de la Torre y Medina Allende, Pabellón Argentina, Ciudad Universitaria, Córdoba 5000, Argentina.
- Departamento de Fisicoquímica, Fac. de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Pabellón Argentina, Ciudad Universitaria, Córdoba 5000, Argentina
- Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Pabellón Argentina, Ciudad Universitaria, Córdoba 5000, Argentina
| | - Gustavo A Pino
- INFIQC: Instituto de Investigaciones en Físico-Química de Córdoba (CONICET - UNC), Haya de la Torre y Medina Allende, Pabellón Argentina, Ciudad Universitaria, Córdoba 5000, Argentina.
- Departamento de Fisicoquímica, Fac. de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Pabellón Argentina, Ciudad Universitaria, Córdoba 5000, Argentina
- Centro Láser de Ciencias Moleculares, Universidad Nacional de Córdoba, Haya de la Torre y Medina Allende, Pabellón Argentina, Ciudad Universitaria, Córdoba 5000, Argentina
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21
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Qiu L, Cooks RG. Spontaneous Oxidation in Aqueous Microdroplets: Water Radical Cation as Primary Oxidizing Agent. Angew Chem Int Ed Engl 2024; 63:e202400118. [PMID: 38302696 DOI: 10.1002/anie.202400118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 01/28/2024] [Accepted: 01/29/2024] [Indexed: 02/03/2024]
Abstract
Exploration of the unique chemical properties of interfaces can unlock new understanding. A striking example is the finding of accelerated reactions, particularly spontaneous oxidation reactions, that occur without assistance of catalysts or external oxidants at the air interface of both aqueous and organic solutions (provided they contain some water). This finding opened a new area of interfacial chemistry but also caused heated debate regarding the primary chemical species responsible for the observed oxidation. An overview of the literature covering oxidation in microdroplets with air interfaces is provided, together with a critical examination of previous findings and hypotheses. The water radical cation/radical anion pair, formed spontaneously and responsible for the electric field at or near the droplet/air interface, is suggested to constitute the primary redox species. Mechanisms of accelerated microdroplet reactions are critically discussed and it is shown that hydroxyl radical/hydrogen peroxide formation in microdroplets does not require that these species be the primary oxidant. Instead, we suggest that hydroxyl radical and hydrogen peroxide are the products of water radical cation decay in water. The importance of microdroplet chemistry in the prebiotic environment is sketched briefly and the role of partial solvation in reaction acceleration is noted.
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Affiliation(s)
- Lingqi Qiu
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, U.S
| | - R Graham Cooks
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, U.S
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22
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Chen X, Xia Y, Wu Y, Xu Y, Jia X, Zare RN, Wang F. Sprayed Oil-Water Microdroplets as a Hydrogen Source. J Am Chem Soc 2024; 146:10868-10874. [PMID: 38573037 DOI: 10.1021/jacs.4c01455] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2024]
Abstract
Liquid water provides the largest hydrogen reservoir on the earth's surface. Direct utilization of water as a source of hydrogen atoms and molecules is fundamental to the evolution of the ecosystem and industry. However, liquid water is an unfavorable electron donor for forming these hydrogen species owing to its redox inertness. We report oil-mediated electron extraction from water microdroplets, which is easily achieved by ultrasonically spraying an oil-water emulsion. Based on charge measurement and electron paramagnetic resonance spectroscopy, contact electrification between oil and a water microdroplet is demonstrated to be the origin of electron extraction from water molecules. This contact electrification results in enhanced charge separation and subsequent mutual neutralization, which enables a ∼13-fold increase of charge carriers in comparison with an ultrapure water spray, leading to a ∼16-fold increase of spray-sourced hydrogen that can hydrogenate CO2 to selectively produce CO. These findings emphasize the potential of charge separation enabled by spraying an emulsion of liquid water and a hydrophobic liquid in driving hydrogenation reactions.
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Affiliation(s)
- Xuke Chen
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Yu Xia
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Yingfeng Wu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- Henan Institute of Advanced Technology, Zhengzhou University, Zhengzhou 450000, P. R. China
| | - Yunpeng Xu
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Xiuquan Jia
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Feng Wang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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23
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Kumar A, Kumar P. Dissociation of H 2O 2 on water surfaces (ice and water droplets). Phys Chem Chem Phys 2024; 26:11331-11339. [PMID: 38563356 DOI: 10.1039/d3cp04107g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
OH radicals are an important constituent of the atmosphere. Therefore, all reactions that act as a source of OH radicals are important. It is known that photo-dissociation of H2O2 is an important source of OH radicals in the atmosphere. In the present study, using Born-Oppenheimer molecular dynamics simulations, we have shown that the H2O2 molecule can dissociate thermally on water droplets, as well as on the surface of ice, to form OH radicals. Furthermore, the dissociation of H2O2 was found to be very fast (less than 50 fs) on the ice surface compared with on the water droplets. We believe this route for the formation of OH radicals could be more critical than photo-dissociation, as it can take place both during the day and at night, but further studies with more sophisticated theoretical approaches or experiments are required to confirm this hypothesis.
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Affiliation(s)
- Amit Kumar
- Department of Chemistry, Malaviya National Institute of Technology Jaipur, Jaipur, 302017, India.
| | - Pradeep Kumar
- Department of Chemistry, Malaviya National Institute of Technology Jaipur, Jaipur, 302017, India.
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24
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Chen H, Wang R, Chiba T, Foreman K, Bowen K, Zhang X. Designer "Quasi-Benzyne": The Spontaneous Reduction of Ortho-Diiodotetrafluorobenzene on Water Microdroplets. J Am Chem Soc 2024; 146:10979-10983. [PMID: 38586980 DOI: 10.1021/jacs.4c02819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2024]
Abstract
It has been widely shown that water microdroplets have a plethora of unique properties that are highly distinct from those of bulk water, among which an especially intriguing one is the strong reducing power as a result of the electrons spontaneously generated at the air-water interface. In this study, we take advantage of the reducing power of water microdroplets to reduce ortho-diiodotetrafluorobenzene (o-C6F4I2) into a C6F4I2•- radical anion. Photoelectron spectroscopy and density functional theory computations reveal that the excess electron in C6F4I2•- occupies the I-C1-C2-I linkage, which elongates the C-I bonds but surprisingly shortens the C1-C2 bond, making the bond order higher than a double bond, similar to the benzyne molecule, so we named it "quasi-benzyne". The C6F4I2•- anion was further successfully utilized in a Diels-Alder reaction, a typical reaction for benzyne. This study provides a good example of strategically utilizing the spontaneous properties of water microdroplets and generating an especially exotic anion, and we anticipate that microdroplet chemistry can be an avenue rich in opportunities for new catalyst-free organic reactions.
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Affiliation(s)
- Huan Chen
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin300071, China
- Haihe Laboratory of Sustainable Chemical Transformations, Tianjin300192, China
| | - Ruijing Wang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin300071, China
- Haihe Laboratory of Sustainable Chemical Transformations, Tianjin300192, China
| | - Tatsuya Chiba
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Kathryn Foreman
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Kit Bowen
- Department of Chemistry, Johns Hopkins University, Baltimore, Maryland 21218, United States
| | - Xinxing Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin300071, China
- Haihe Laboratory of Sustainable Chemical Transformations, Tianjin300192, China
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25
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Rodriguez HM, Martyniuk M, Iyer KS, Ciampi S. Insulator-on-Conductor Fouling Amplifies Aqueous Electrolysis Rates. J Am Chem Soc 2024; 146:10299-10311. [PMID: 38591156 DOI: 10.1021/jacs.3c11238] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/10/2024]
Abstract
The chemical industry is a major consumer of fossil fuels. Several chemical reactions of practical value proceed with the gain or loss of electrons, opening a path to integrate renewable electricity into chemical manufacturing. However, most organic molecules have low aqueous solubility, causing green and cheap electricity-driven reactions to suffer from intrinsically low reaction rates in industry's solvent of choice: water. Here, we show that a strategic, partial electrode fouling with hydrophobic insulators (oils and plastics) offsets kinetic limitations caused by poor reactant solubility, opening a new path for the direct integration of renewable electricity into the production of commodity chemicals. Through electrochemiluminescence microscopy, we reveal for the oxidation of organic reactants up to 6-fold reaction rate increase at the "fouled" oil-electrolyte-electrode interface relative to clean electrolyte-electrode areas. Analogously, electrodes partially masked (fouled) with plastic patterns, deposited either photolithographically (photoresists) or manually (inexpensive household glues and sealants), outperform clean electrodes. The effect is not limited to reactants of limited water solubility, and, for example, net gold electrodeposition rates are up to 22% larger at fouled than clean electrodes. In a system involving a surface-active reactant, rate augmentation is driven by the synergy between insulator-confined reactant enrichment and insulator-induced current crowding, whereas only the latter and possibly localized decrease in iR drop near the insulator are relevant in a system composed of non-surface-active species. Our counterintuitive electrode design enhances electrolysis rates despite the diminished area of intimate electrolyte-electrode contact and introduces a new path for upscaling aqueous electrochemical processes.
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Affiliation(s)
- Harry Morris Rodriguez
- School of Molecular and Life Sciences, Curtin University, Bentley, Western Australia 6102, Australia
| | - Mariusz Martyniuk
- Department of Electrical, Electronic and Computer Engineering, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Killugudi Swaminathan Iyer
- School of Molecular Sciences, The University of Western Australia, Crawley, Western Australia 6009, Australia
| | - Simone Ciampi
- School of Molecular and Life Sciences, Curtin University, Bentley, Western Australia 6102, Australia
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Song Z, Zhu C, Gong K, Wang R, Zhang J, Zhao S, Li Z, Zhang X, Xie J. Deciphering the Microdroplet Acceleration Factors of Aza-Michael Addition Reactions. J Am Chem Soc 2024; 146:10963-10972. [PMID: 38567839 DOI: 10.1021/jacs.4c02312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/18/2024]
Abstract
Microdroplet chemistry is emerging as a great tool for accelerating reactions by several orders of magnitude. Several unique properties such as extreme pHs, interfacial electric fields (IEFs), and partial solvation have been reported to be responsible for the acceleration; however, which factor plays the key role remains elusive. Here, we performed quantum chemical calculations to explore the underlying mechanisms of an aza-Michael addition reaction between methylamine and acrylamide. We showed that the acceleration in methanol microdroplets results from the cumulative effects of several factors. The acidic surface of the microdroplet plays a dominating role, leading to a decrease of ∼9 kcal/mol in the activation barrier. We speculated that the dissociation of both methanol and trace water contributes to the surface acidity. An IEF of 0.1 V/Å can further decrease the barrier by ∼2 kcal/mol. Partial solvation has a negligible effect on lowering the activation barrier in microdroplets but can increase the collision frequency between reactants. With acidity revealed to be the major accelerating factor for methanol droplets, reactions on water microdroplets should have even higher rates because water is more acidic. Both theoretically and experimentally, we confirmed that water microdroplets significantly accelerate the aza-Michael reaction, achieving an acceleration factor that exceeds 107. This work elucidates the multifactorial influences on the microdroplet acceleration mechanism, and with such detailed mechanistic investigations, we anticipate that microdroplet chemistry will be an avenue rich in opportunities in the realm of green synthesis.
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Affiliation(s)
- Zhexuan Song
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Chenghui Zhu
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Ke Gong
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Ruijing Wang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Jianze Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Supin Zhao
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Zesheng Li
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Xinxing Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
| | - Jing Xie
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
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27
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Song X, Yan H, Zhang Y, Zhou W, Li S, Zhang J, Ciampi S, Zhang L. Hydroxylation of the indium tin oxide electrode promoted by surface bubbles. Chem Commun (Camb) 2024; 60:4186-4189. [PMID: 38530669 DOI: 10.1039/d4cc00307a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
Adherent bubbles at electrodes are generally treated as reaction penalties. Herein, in situ hydroxylation of indium tin oxide surfaces can be easily achieved by applying a constant potential of +1.0 V in the presence of bubbles. Its successful hydroxylation is further demonstrated by preparing a ferrocene-terminated film, which is confirmed by cyclic voltammetry and X-ray photoelectron spectroscopy.
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Affiliation(s)
- Xiaoxue Song
- Institute of Quantum and Sustainable Technology (IQST), School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang City, 212013, Jiangsu Province, China.
| | - Hui Yan
- Institute of Quantum and Sustainable Technology (IQST), School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang City, 212013, Jiangsu Province, China.
| | - Yuqiao Zhang
- Institute of Quantum and Sustainable Technology (IQST), School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang City, 212013, Jiangsu Province, China.
| | - Weiqiang Zhou
- Institute of Quantum and Sustainable Technology (IQST), School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang City, 212013, Jiangsu Province, China.
| | - Shun Li
- Institute of Quantum and Sustainable Technology (IQST), School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang City, 212013, Jiangsu Province, China.
| | - Jianming Zhang
- Institute of Quantum and Sustainable Technology (IQST), School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang City, 212013, Jiangsu Province, China.
| | - Simone Ciampi
- School of Molecular and Life Sciences, Curtin University, Bentley, Western Australia 6102, Australia.
| | - Long Zhang
- Institute of Quantum and Sustainable Technology (IQST), School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang City, 212013, Jiangsu Province, China.
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28
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Zhang W, Yuan K, Zheng J, Wang X, Wang X, Song Z, Zhang L, Hu J. Effects of Nanobubbles on Photochemical Processes of Levofloxacin Photosensitizer. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:7021-7028. [PMID: 38501919 DOI: 10.1021/acs.langmuir.4c00041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
Photodynamic therapy (PDT) stands as an efficacious modality for the treatment of cancer and various diseases, in which optimization of the electron transfer and augmentation of the production of lethal reactive oxygen species (ROS) represent pivotal challenges to enhance its therapeutic efficacy. Empirical investigations have established that the spontaneous initiation of redox reactions associated with electron transfer is feasible and is located in the gas-liquid interfaces. Meanwhile, nanobubbles (NBs) are emerging as entities capable of furnishing a plethora of such interfaces, attributed to their stability and large surface/volume ratio in bulk water. Thus, NBs provide a chance to expedite the electron-transfer kinetics within the context of PDT in an ambient environment. In this paper, we present a pioneering exploration into the impact of nitrogen nanobubbles (N2-NBs) on the electron transfer of the photosensitizer levofloxacin (LEV). Transient absorption spectra and time-resolved decay spectra, as determined through laser flash photolysis, unequivocally reveal that N2-NBs exhibit a mitigating effect on the decay of the LEV excitation triplet state, thereby facilitating subsequent processes. Of paramount significance is the observation that the presence of N2-NBs markedly accelerates the electron transfer of LEV, albeit with a marginal inhibitory influence on its energy-transfer reaction. This observation is corroborated through absorbance measurements and offers compelling evidence substantiating the role of NBs in expediting electron transfer within the ambit of PDT. The mechanism elucidated herein sheds light on how N2-NBs intricately influence both electron-transfer and energy-transfer reactions in the photosensitizer LEV. These findings not only contribute to a nuanced understanding of the underlying processes but also furnish novel insights that may inform the application of NBs in the realm of photodynamic therapy.
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Affiliation(s)
- Wenpan Zhang
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Kaiwei Yuan
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jin Zheng
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xingya Wang
- Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
| | - Xiaotian Wang
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhejun Song
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Lijuan Zhang
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
| | - Jun Hu
- Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800, China
- Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai 201204, China
- Xiangfu Laboratory, Jiashan 314102, China
- Institute of Materiobiology, College of Science, Shanghai University, Shanghai 200444, China
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29
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Zhang R, Zhang Z, Chen X, Jiang J, Hua L, Jia X, Bao R, Wang F. Pyrogenic Carbon Degradation by Galvanic Coupling with Sprayed Seawater Microdroplets. J Am Chem Soc 2024; 146:8528-8535. [PMID: 38497738 DOI: 10.1021/jacs.4c00290] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Surface waves are known for their mechanical role in coastal processes that influence the weather and climate. However, their chemical impact, particularly on the transformation of pyrogenic carbon, is poorly understood. Pyrogenic carbon is generally assumed to show negligible postformational alteration of its stable carbon isotope composition. Here we present an electrochemical interaction of pyrogenic carbon with the sprayed seawater microdroplets resulting from wave breaking, driven by the galvanic coupling between the microdroplet water-carbon interfaces and the microdroplet water-vapor interfaces. This enables refractory pyrogenic carbon to rapidly degrade via the oxygenation and mineralization reaction, which makes it ∼2.6‰ enriched in 13C, far exceeding the generally assumed postformation alteration values (<0.5‰) of pyrogenic carbon. The unique chemical dynamics of seawater microdroplets provide new insights into the discrepancy in carbon isotope signatures between riverine and marine black carbon, emphasizing the potential of coastal oceans for carbon sequestration in the global carbon cycle.
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Affiliation(s)
- Ruolan Zhang
- Henan Institute of Advanced Technology, Zhengzhou University, Zhengzhou 450000, P. R. China
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Zhenyuan Zhang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Xuke Chen
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
| | - Jichun Jiang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Lei Hua
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Xiuquan Jia
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
| | - Rui Bao
- Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Lab of Marine Chemistry Theory and Technology, Ocean University of China, Qingdao 266100, P. R. China
| | - Feng Wang
- State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P. R. China
- University of Chinese Academy of Sciences, Beijing 100049, P. R. China
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30
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Angelaki M, Carreira Mendes Da Silva Y, Perrier S, George C. Quantification and Mechanistic Investigation of the Spontaneous H 2O 2 Generation at the Interfaces of Salt-Containing Aqueous Droplets. J Am Chem Soc 2024; 146:8327-8334. [PMID: 38488457 PMCID: PMC10979748 DOI: 10.1021/jacs.3c14040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
There is now much evidence that OH radicals and H2O2 are spontaneously generated at the air-water interface of atmospheric aerosols. Here, we investigated the effect of halide anions (Cl-, Br-, I-), which are abundant in marine aerosols, on this H2O2 production. Droplets were generated via nebulization of water solutions containing Na2SO4, NaCl, NaBr, and NaI containing solutions, and H2O2 was monitored as a function of the salt concentration under atmospheric relevant conditions. The interfacial OH radical formation was also investigated by adding terephthalic acid (TA) to our salt solutions, and the product of its reaction with OH, hydroxy terephthalic acid (TAOH), was monitored. Finally, a mechanistic investigation was performed to examine the reactions participating in H2O2 production, and their respective contributions were quantified. Our results showed that only Br- contributes to the interfacial H2O2 formation, promoting the production by acting as an electron donor, while Na2SO4 and NaCl stabilized the droplets by only reducing their evaporation. TAOH was observed in the collected droplets and, for the first time, directly in the particle phase by means of online fluorescence spectroscopy, confirming the interfacial OH production. A mechanistic study suggests that H2O2 is formed by both OH and HO2 self-recombination, as well as HO2 reaction with H atoms. This work is expected to enhance our understanding of interfacial processes and assess their impact on climate, air quality, and health.
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Affiliation(s)
- Maria Angelaki
- Université Claude Bernard Lyon 1, CNRS, IRCELYON, UMR 5256, F-69626, Villeurbanne, France
| | | | - Sébastien Perrier
- Université Claude Bernard Lyon 1, CNRS, IRCELYON, UMR 5256, F-69626, Villeurbanne, France
| | - Christian George
- Université Claude Bernard Lyon 1, CNRS, IRCELYON, UMR 5256, F-69626, Villeurbanne, France
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31
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Gong K, Meng Y, Zare RN, Xie J. Molecular Mechanism for Converting Carbon Dioxide Surrounding Water Microdroplets Containing 1,2,3-Triazole to Formic Acid. J Am Chem Soc 2024; 146:8576-8584. [PMID: 38488449 DOI: 10.1021/jacs.4c00529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2024]
Abstract
Spraying water microdroplets containing 1,2,3-triazole (Tz) has been found to effectively convert gas-phase carbon dioxide (CO2), but not predissolved CO2, into formic acid (FA). Herein, we elucidate the reaction mechanism at the molecular level through quantum chemistry calculations and ab initio molecular dynamics (AIMD) simulations. Computations suggest a multistep reaction mechanism that initiates from the adsorption of CO2 by Tz to form a CO2-Tz complex (named reactant complex (RC)). Then, the RC either is reduced by electrons that were generated at the air-liquid interface of the water microdroplet and then undergoes intramolecular proton transfer (PT) or switches the reduction and PT steps to form a [HCO2-(Tz-H)]- complex (named PC-). Subsequently, PC- undergoes reduction and the C-N bond dissociates to generate COOH- and [Tz-H]- (m/z = 69). COOH- easily converts to HCOOH and is captured at m/z = 45 in mass spectroscopy. Notably, the intramolecular PT step can be significantly lowered by the oriented electric field at the interface and a water-bridge mechanism. The mechanism is further confirmed by testing multiple azoles. The AIMD simulations reveal a novel proton transfer mechanism where water serves as a transporter and is shown to play an important role dynamically. Moreover, the transient •COOH captured by the experiment is proposed to be partly formed by the reaction with H•, pointing again to the importance of the air-water interface. This work provides valuable insight into the important mechanistic, kinetic, and dynamic features of converting gas-phase CO2 to valuable products by azoles or amines dissolved in water microdroplets.
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Affiliation(s)
- Ke Gong
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Yifan Meng
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Jing Xie
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
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32
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Krushinski LE, Dick JE. Direct electrochemical evidence suggests that aqueous microdroplets spontaneously produce hydrogen peroxide. Proc Natl Acad Sci U S A 2024; 121:e2321064121. [PMID: 38466847 PMCID: PMC10962973 DOI: 10.1073/pnas.2321064121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 01/30/2024] [Indexed: 03/13/2024] Open
Abstract
Recent reports have detailed the striking observation that electroactive molecules, such as hydrogen peroxide (H2O2) and radical water species (H2O.+/H2O.-), are spontaneously produced in aqueous microdroplets. Stochastic electrochemistry allows one to study reactions in real-time occurring inside subfemtoliter droplets, one droplet at a time, when a microdroplet irreversibly adsorbs to an ultramicroelectrode surface (radius ~ 5 µm). Here, we use stochastic electrochemistry to probe the formation of hydrogen peroxide (H2O2) in single aqueous microdroplets suspended in 1,2-dichloroethane. The oxidation of H2O2 at alkaline pH (11.5) differs from near-neutral conditions (6.4), allowing us to create a digital, turn-off sensing modality for the presence of H2O2. Further, we show that the stochastic electrochemical signal is highest at the mass transfer limitation of the H2O2 couple and is dampened when the potential nears the formal potential. We validate these results by showing that the addition of a H2O2 selective probe, luminol, decreases the stochastic electrochemical response at alkaline pH (11.5). Our results support the observation that H2O2 is generated in water microdroplets at concentrations of ~100 s of µM.
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Affiliation(s)
| | - Jeffrey E. Dick
- Department of Chemistry, Purdue University, West Lafayette, IN47907
- Elmore Family School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN47907
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33
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Yu Q, Yao Z, Zhou J, Yu W, Zhuang C, Qi Y, Xiong H. Transient stimulated Raman scattering spectroscopy and imaging. LIGHT, SCIENCE & APPLICATIONS 2024; 13:70. [PMID: 38453917 PMCID: PMC10920877 DOI: 10.1038/s41377-024-01412-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 02/05/2024] [Accepted: 02/17/2024] [Indexed: 03/09/2024]
Abstract
Stimulated Raman scattering (SRS) has been developed as an essential quantitative contrast for chemical imaging in recent years. However, while spectral lines near the natural linewidth limit can be routinely achieved by state-of-the-art spontaneous Raman microscopes, spectral broadening is inevitable for current mainstream SRS imaging methods. This is because those SRS signals are all measured in the frequency domain. There is a compromise between sensitivity and spectral resolution: as the nonlinear process benefits from pulsed excitations, the fundamental time-energy uncertainty limits the spectral resolution. Besides, the spectral range and acquisition speed are mutually restricted. Here we report transient stimulated Raman scattering (T-SRS), an alternative time-domain strategy that bypasses all these fundamental conjugations. T-SRS is achieved by quantum coherence manipulation: we encode the vibrational oscillations in the stimulated Raman loss (SRL) signal by femtosecond pulse-pair sequence excited vibrational wave packet interference. The Raman spectrum was then achieved by Fourier transform of the time-domain SRL signal. Since all Raman modes are impulsively and simultaneously excited, T-SRS features the natural-linewidth-limit spectral line shapes, laser-bandwidth-determined spectral range, and improved sensitivity. With ~150-fs laser pulses, we boost the sensitivity of typical Raman modes to the sub-mM level. With all-plane-mirror high-speed time-delay scanning, we further demonstrated hyperspectral SRS imaging of live-cell metabolism and high-density multiplexed imaging with the natural-linewidth-limit spectral resolution. T-SRS shall find valuable applications for advanced Raman imaging.
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Affiliation(s)
- Qiaozhi Yu
- National Biomedical Imaging Center, College of Future Technology, Peking University, Beijing, 100871, China
| | - Zhengjian Yao
- National Biomedical Imaging Center, College of Future Technology, Peking University, Beijing, 100871, China
| | - Jiaqi Zhou
- National Biomedical Imaging Center, College of Future Technology, Peking University, Beijing, 100871, China
| | - Wenhao Yu
- Biomedical Engineering Department, College of Future Technology, Peking University, Beijing, 100871, China
| | - Chenjie Zhuang
- Biomedical Engineering Department, College of Future Technology, Peking University, Beijing, 100871, China
| | - Yafeng Qi
- National Biomedical Imaging Center, College of Future Technology, Peking University, Beijing, 100871, China
| | - Hanqing Xiong
- National Biomedical Imaging Center, College of Future Technology, Peking University, Beijing, 100871, China.
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34
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Song X, Zare RN. The power of microdroplet photochemistry. Chem Sci 2024; 15:3670-3672. [PMID: 38454998 PMCID: PMC10915808 DOI: 10.1039/d4sc00056k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2024] [Accepted: 02/01/2024] [Indexed: 03/09/2024] Open
Abstract
This study presents compelling evidence demonstrating that irradiation of the air-solution interface, whether achieved through the spraying of microdroplets into the air or by bubbling air through a solution, significantly accelerates the rate of photochemical reactions by orders of magnitude compared to identical reaction conditions in bulk solutions. We propose this approach as a novel and versatile method for harnessing solar energy in chemical transformations.
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Affiliation(s)
- Xiaowei Song
- Department of Chemistry, Stanford University Stanford California 94305 USA
| | - Richard N Zare
- Department of Chemistry, Stanford University Stanford California 94305 USA
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35
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Cassone G, Martelli F. Electrofreezing of liquid water at ambient conditions. Nat Commun 2024; 15:1856. [PMID: 38424051 PMCID: PMC10904787 DOI: 10.1038/s41467-024-46131-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 02/12/2024] [Indexed: 03/02/2024] Open
Abstract
Water is routinely exposed to external electric fields. Whether, for example, at physiological conditions, in contact with biological systems, or at the interface of polar surfaces in countless technological settings, water responds to fields on the order of a few V Å-1 in a manner that is under intense investigation. Dating back to the 19th century, the possibility of solidifying water upon applying electric fields - a process known as electrofreezing - is an alluring promise that has canalized major efforts since, with uncertain outcomes. Here, we perform long (up to 500 ps per field strength) ab initio molecular dynamics simulations of water at ambient conditions under external electric fields. We show that fields of 0.10 - 0.15 V Å-1 induce electrofreezing to a ferroelectric amorphous phase which we term f-GW (ferroelectric glassy water). The transition occurs after ~ 150 ps for a field of 0.15 V Å-1 and after ~ 200 ps for a field of 0.10 V Å-1 and is signaled by a structural and dynamic arrest and the suppression of the fluctuations of the hydrogen bond network. Our work reports evidence of electrofreezing of bulk liquid water at ambient conditions and therefore impacts several fields, from fundamental chemical physics to biology and catalysis.
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Affiliation(s)
- Giuseppe Cassone
- Institute for Chemical-Physical Processes, National Research Council, Viale F. Stagno d'Alcontres 37, Messina, 98158, Italy.
| | - Fausto Martelli
- IBM Research Europe, Keckwik Lane, Daresbury, WA4 4AD, UK.
- Department of Chemical Engineering, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
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36
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Eatoo MA, Mishra H. Busting the myth of spontaneous formation of H 2O 2 at the air-water interface: contributions of the liquid-solid interface and dissolved oxygen exposed. Chem Sci 2024; 15:3093-3103. [PMID: 38425539 PMCID: PMC10901496 DOI: 10.1039/d3sc06534k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Accepted: 01/22/2024] [Indexed: 03/02/2024] Open
Abstract
Recent reports on the spontaneous formation of hydrogen peroxide (H2O2) at the air-water and solid-water interfaces challenge our current understanding of aquatic chemistry and have ramifications on atmosphere chemistry models, surface science, and green chemistry. Suggested mechanisms underlying this chemical transformation include ultrahigh instantaneous electric fields at the air-water interface and the oxidation of water and reduction of the solid at the solid-water interface. Here, we revisit this curious problem with NMR spectroscopy (with an H2O2 detection limit ≥50 nM) and pay special attention to the effects of nebulizing gas, dissolved oxygen content, and the solid-water interface on this chemical transformation in condensed and sprayed water microdroplets. Experiments reveal that the reduction of dissolved oxygen at the solid-water interface predominantly contributes to the H2O2 formation (not the oxidation of hydroxyl ions at the air-water interface or the oxidation of water at the solid-water interface). We find that the H2O2 formation is accompanied by the consumption (i.e., reduction) of dissolved oxygen and the oxidation of the solid surface, i.e., in the absence of dissolved oxygen, the formation of H2O2(aq) is not observed within the detection limit of ≥50 nM. Remarkably, the tendency of the solids investigated in this work towards forming H2O2 in water followed the same order as their positions in the classic Galvanic series. These findings bust the prevailing myths surrounding H2O2 formation due to the air-water interface, the ultrahigh electric fields therein, or the micro-scale of droplets. The hitherto unrealized role of the oxidation of the solid surface due to dissolved oxygen in the formation of H2O2 is exposed. These findings are especially relevant to corrosion science, surface science, and electrochemistry, among others.
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Affiliation(s)
- Muzzamil Ahmad Eatoo
- Environmental Science and Engineering (EnSE) Program, Biological and Environmental Science and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST) 23955-6900 Thuwal Kingdom of Saudi Arabia
- Water Desalination and Reuse Center (WDRC), King Abdullah University of Science and Technology (KAUST) 23955-6900 Thuwal Kingdom of Saudi Arabia
| | - Himanshu Mishra
- Environmental Science and Engineering (EnSE) Program, Biological and Environmental Science and Engineering (BESE) Division, King Abdullah University of Science and Technology (KAUST) 23955-6900 Thuwal Kingdom of Saudi Arabia
- Water Desalination and Reuse Center (WDRC), King Abdullah University of Science and Technology (KAUST) 23955-6900 Thuwal Kingdom of Saudi Arabia
- Center for Desert Agriculture (CDA), King Abdullah University of Science and Technology (KAUST) 23955-6900 Thuwal Kingdom of Saudi Arabia
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37
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Martins-Costa MTC, Ruiz-López MF. Reactivity of Monoethanolamine at the Air-Water Interface and Implications for CO 2 Capture. J Phys Chem B 2024; 128:1289-1297. [PMID: 38279927 DOI: 10.1021/acs.jpcb.3c06856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2024]
Abstract
The development of CO2-capture technologies is key to mitigating climate change due to anthropogenic greenhouse gas emissions. These cover a number of technologies designed to reduce the level of CO2 emitted into the atmosphere or to eliminate CO2 from ambient air. In this context, amine-based sorbents in aqueous solutions are broadly used in most advanced separation techniques currently implemented in industrial applications. It has been reported that the gas/liquid interface plays an important role in the early stages of the capture process, but how the interface influences the chemistry is still a matter of debate. With the help of first-principles molecular dynamics simulations, we show that monoethanolamine (MEA), a prototypical sorbent molecule, has a weak affinity for the air-water interface, where in addition it exhibits a lower nucleophilicity compared to bulk solution. The change in reactivity is due to the combination of structural and electronic factors, namely, the shift of the conformational equilibrium and the stabilization of the N-atom lone pair. Based on these results, strategies for improving the efficiency of alkanolamine sorbents are proposed.
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Affiliation(s)
- Marilia T C Martins-Costa
- Laboratoire de Physique et Chimie Théoriques, UMR CNRS 7019, University of Lorraine, CNRS, BP 70239, 54506 Vandoeuvre-lès-Nancy, France
| | - Manuel F Ruiz-López
- Laboratoire de Physique et Chimie Théoriques, UMR CNRS 7019, University of Lorraine, CNRS, BP 70239, 54506 Vandoeuvre-lès-Nancy, France
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38
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Devlin SW, Bernal F, Riffe EJ, Wilson KR, Saykally RJ. Spiers Memorial Lecture: Water at interfaces. Faraday Discuss 2024; 249:9-37. [PMID: 37795954 DOI: 10.1039/d3fd00147d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/06/2023]
Abstract
In this article we discuss current issues in the context of the four chosen subtopics for the meeting: dynamics and nano-rheology of interfacial water, electrified/charged aqueous interfaces, ice interfaces, and soft matter/water interfaces. We emphasize current advances in both theory and experiment, as well as important practical manifestations and areas of unresolved controversy.
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Affiliation(s)
- Shane W Devlin
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
- Chemical Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA
| | - Franky Bernal
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
- Chemical Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA
| | - Erika J Riffe
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
- Chemical Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA
| | - Kevin R Wilson
- Chemical Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA
| | - Richard J Saykally
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
- Chemical Sciences Division, Lawrence Berkeley National Lab, Berkeley, CA 94720, USA
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39
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Bonn M. Concluding remarks for Faraday Discussion on Water at Interfaces. Faraday Discuss 2024; 249:521-525. [PMID: 38099817 PMCID: PMC10845007 DOI: 10.1039/d3fd00153a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 11/14/2023] [Indexed: 02/07/2024]
Abstract
Water at interfaces is a fascinating and multifaceted topic that has garnered significant attention in various scientific fields due to its relevance and implications. This Faraday Discussion explored the complexity of water at different interfaces. Many of the reports highlight the need for a molecular-level understanding. The Discussion was lively and constructive. In these summarizing remarks, I do not aim to be complete, but will rather try to sketch the status of the field, highlight the progress that we as a community have made, and present eclectic examples of where more work needs to be done.
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Affiliation(s)
- Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.
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40
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Zhao G, Li Y, Zhen W, Gao J, Gu Y, Hong B, Han X, Zhao S, Pera-Titus M. Enhanced Biphasic Reactions in Amphiphilic Silica Mesopores. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2024; 128:1644-1653. [PMID: 38322775 PMCID: PMC10839897 DOI: 10.1021/acs.jpcc.3c07477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2023] [Revised: 12/21/2023] [Accepted: 01/02/2024] [Indexed: 02/08/2024]
Abstract
In this study, we investigated the effect of the pore volume and mesopore size of surface-active catalytic organosilicas on the genesis of particle-stabilized (Pickering) emulsions for the dodecanal/ethylene glycol system and their reactivity for the acid-catalyzed biphasic acetalization reaction. To this aim, we functionalized a series of fumed silica superparticles (size 100-300 nm) displaying an average mesopore size in the range of 11-14 nm and variable mesopore volume, with a similar surface density of octyl and propylsulfonic acid groups. The modified silica superparticles were characterized in detail using different techniques, including acid-base titration, thermogravimetric analysis, TEM, and dynamic light scattering. The pore volume of the particles impacts their self-assembly and coverage at the dodecanal/ethylene glycol (DA/EG) interface. This affects the stability and the average droplet size of emulsions and conditions of the available interfacial surface area for reaction. The maximum DA-EG productivity is observed for A200 super-SiNPs with a pore volume of 0.39 cm3·g-1 with an interfacial coverage by particles lower than 1 (i.e., submonolayer). Using dissipative particle dynamics and all-atom grand canonical Monte Carlo simulations, we unveil a stabilizing role of the pore volume of porous silica superparticles for generating emulsions and local micromixing of immiscible dodecanal and ethylene glycol, allowing fast and efficient solvent-free acetalization in the presence of Pickering emulsions. The micromixing level is interrelated to the adsorption energy of self-assembled particles at the DA/EG interface.
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Affiliation(s)
- Guolin Zhao
- Eco-Efficient
Products and Processes Laboratory (E2P2L), UMI 3464 CNRS − Solvay, 3966 Jin Du Road, Xin Zhuang Ind. Zone, Shanghai 201108, China
- State
Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Yao Li
- Eco-Efficient
Products and Processes Laboratory (E2P2L), UMI 3464 CNRS − Solvay, 3966 Jin Du Road, Xin Zhuang Ind. Zone, Shanghai 201108, China
- State
Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Wen Zhen
- School
of Chemistry and Chemical Engineering, Guangxi
University, Nanning 530004, China
| | - Jie Gao
- Eco-Efficient
Products and Processes Laboratory (E2P2L), UMI 3464 CNRS − Solvay, 3966 Jin Du Road, Xin Zhuang Ind. Zone, Shanghai 201108, China
| | - Yunjiao Gu
- Eco-Efficient
Products and Processes Laboratory (E2P2L), UMI 3464 CNRS − Solvay, 3966 Jin Du Road, Xin Zhuang Ind. Zone, Shanghai 201108, China
| | - Bing Hong
- Eco-Efficient
Products and Processes Laboratory (E2P2L), UMI 3464 CNRS − Solvay, 3966 Jin Du Road, Xin Zhuang Ind. Zone, Shanghai 201108, China
| | - Xia Han
- State
Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Shuangliang Zhao
- State
Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China
- School
of Chemistry and Chemical Engineering, Guangxi
University, Nanning 530004, China
| | - Marc Pera-Titus
- Eco-Efficient
Products and Processes Laboratory (E2P2L), UMI 3464 CNRS − Solvay, 3966 Jin Du Road, Xin Zhuang Ind. Zone, Shanghai 201108, China
- Cardiff
Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff CF10 3AT, U.K.
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41
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Zhou K, Su H, Gao J, Li H, Liu S, Yi X, Zhang Z, Wang W. Deciphering the Kinetics of Spontaneous Generation of H 2O 2 in Individual Water Microdroplets. J Am Chem Soc 2024; 146:2445-2451. [PMID: 38230586 DOI: 10.1021/jacs.3c09864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
Spontaneous generation of H2O2 in sub-10 μm-sized water microdroplets has received increasing interest since its first discovery in 2019. On the other hand, due to the short lifetime of these microdroplets (rapid evaporation) and lack of suitable tools to real-time monitor the generation of H2O2 in individual microdroplets, such a seemingly thermodynamically unfavorable process has also raised vigorous debates on the origin of H2O2 and the underlying mechanism. Herein, we prepared water microdroplets with a long lifetime (>1 h) by virtue of microwell confinement and dynamically monitored the spontaneous generation of H2O2 in individual microdroplets via time-lapsed fluorescence imaging. It was unveiled that H2O2 was continuously generated in the as-prepared water microdroplets and an apparent equilibrium concentration of ∼3 μM of H2O2 in the presence of a H2O2-consuming reaction can be obtained. Through engineering the geometry of these microdroplets, we further revealed that the generation rates of H2O2 in individual microdroplets were positively proportional to their surface-to-volume ratios. This also allowed us to extract a maximal H2O2 generation rate of 7.7 nmol m-2 min-1 in the presence of a H2O2-consuming reaction and derive the corresponding probability of spontaneous conversion of interfacial H2O into H2O2 for the first time, that is, ∼1 of 65,000 water molecules in 1 s. These findings delivered strong evidence that the spontaneous generation of H2O2 indeed occurs at the surface of microdroplets and provided us with an important starting point to further enhance the yield of H2O2 in water microdroplets for future applications.
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Affiliation(s)
- Kai Zhou
- State Key Laboratory of Analytical Chemistry for Life Science, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Hua Su
- School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, China
| | - Jia Gao
- State Key Laboratory of Analytical Chemistry for Life Science, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Haoran Li
- State Key Laboratory of Analytical Chemistry for Life Science, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Shasha Liu
- State Key Laboratory of Analytical Chemistry for Life Science, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Xuannuo Yi
- State Key Laboratory of Analytical Chemistry for Life Science, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
| | - Zhibing Zhang
- Key Laboratory of Mesoscopic Chemistry of Ministry of Education (MOE), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing, 210023, China
| | - Wei Wang
- State Key Laboratory of Analytical Chemistry for Life Science, Chemistry and Biomedicine Innovation Center (ChemBIC), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China
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42
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Wang Z, Dong X, Li XF, Feng Y, Li S, Tang W, Wang ZL. A contact-electro-catalysis process for producing reactive oxygen species by ball milling of triboelectric materials. Nat Commun 2024; 15:757. [PMID: 38272926 PMCID: PMC10810876 DOI: 10.1038/s41467-024-45041-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Accepted: 01/10/2024] [Indexed: 01/27/2024] Open
Abstract
Ball milling is a representative mechanochemical strategy that uses the mechanical agitation-induced effects, defects, or extreme conditions to activate substrates. Here, we demonstrate that ball grinding could bring about contact-electro-catalysis (CEC) by using inert and conventional triboelectric materials. Exemplified by a liquid-assisted-grinding setup involving polytetrafluoroethylene (PTFE), reactive oxygen species (ROS) are produced, despite PTFE being generally considered as catalytically inert. The formation of ROS occurs with various polymers, such as polydimethylsiloxane (PDMS) and polypropylene (PP), and the amount of generated ROS aligns well with the polymers' contact-electrification abilities. It is suggested that mechanical collision not only maximizes the overlap in electron wave functions across the interface, but also excites phonons that provide the energy for electron transition. We expect the utilization of triboelectric materials and their derived CEC could lead to a field of ball milling-assisted mechanochemistry using any universal triboelectric materials under mild conditions.
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Affiliation(s)
- Ziming Wang
- CAS Center for Excellence in Nanoscience, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100140, China
- School of Nanoscience and Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xuanli Dong
- CAS Center for Excellence in Nanoscience, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100140, China
- School of Nanoscience and Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Xiao-Fen Li
- Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China
| | - Yawei Feng
- CAS Center for Excellence in Nanoscience, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100140, China
- Department of Mechanical Engineering, City University of Hong Kong, Hong Kong, 999077, P. R. China
| | - Shunning Li
- School of Advanced Materials, Shenzhen Graduate School, Peking University, Shenzhen, 518055, China
| | - Wei Tang
- CAS Center for Excellence in Nanoscience, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100140, China.
- School of Nanoscience and Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Zhong Lin Wang
- CAS Center for Excellence in Nanoscience, Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, 100140, China.
- School of Nanoscience and Engineering, University of Chinese Academy of Sciences, Beijing, 100049, China.
- School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332-0245, USA.
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43
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Dong J, Chen J, Wang W, Wei Z, Tian ZQ, Fan FR. Charged Microdroplets as Microelectrochemical Cells for CO 2 Reduction and C-C Coupling. J Am Chem Soc 2024; 146:2227-2236. [PMID: 38224553 DOI: 10.1021/jacs.3c12586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2024]
Abstract
Charged microdroplets offer novel electrochemical environments, distinct from traditional solid-liquid or solid-liquid-gas interfaces, due to the intense electric fields at liquid-gas interfaces. In this study, we propose that charged microdroplets serve as microelectrochemical cells (MECs), enabling unique electrochemical reactions at the gas-liquid interface. Using electrospray-generated microdroplets, we achieved multielectron CO2 reduction and C-C coupling to synthesize ethanol using molecular catalysts. These catalysts effectively harness and relay electrons, enhancing the longevity of solvated electrons and enabling multielectron reactions. Importantly, we revealed the intrinsic relationship between the size and charge density of a MEC and its reaction selectivity. Employing in situ mass spectrometry, we identified reaction intermediates (molecular catalyst adducts with HCOO) and oxidation products, elucidating the CO2 reduction mechanism and the comprehensive reaction procedure. Our research underscores the promising role of charged microdroplets in pioneering new electrochemical systems.
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Affiliation(s)
- Jianing Dong
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen 361005, China
| | - Jianxiong Chen
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Wenxin Wang
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Zhenwei Wei
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Zhong-Qun Tian
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen 361005, China
| | - Feng Ru Fan
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen 361005, China
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44
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Wang Y, Dong J, Song X, Luo K, Nan ZA, Fan FR, Tian ZQ. Utilization of charged microdroplets for the controlled rapid synthesis of hollow sodium chloride single crystals. Chem Commun (Camb) 2024; 60:980-983. [PMID: 38165770 DOI: 10.1039/d3cc05640f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2024]
Abstract
Charged microdroplets are favored in microfluidic control, biomedicine, chemistry and materials processing due to their unique physicochemical environment, including interface double layers, high electric fields, surface concentration enrichment, and more. Herein, we investigated the crystallization of charged sodium chloride microdroplets and achieved the formation of hollow single crystals in a single-step process lasting only a few seconds, without the use of templates. Additionally, we discussed the plausible crystal growth mechanism, which appears to be an unconventional outward-inward growth process.
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Affiliation(s)
- Yanjie Wang
- Department of Chemistry, College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen 361005, China.
| | - Jianing Dong
- Department of Chemistry, College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen 361005, China.
| | - Xianmeng Song
- Department of Chemistry, College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen 361005, China.
| | - Kai Luo
- Department of Chemistry, College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen 361005, China.
| | - Zi-Ang Nan
- Department of Chemistry, College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen 361005, China.
| | - Feng Ru Fan
- Department of Chemistry, College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen 361005, China.
| | - Zhong-Qun Tian
- Department of Chemistry, College of Chemistry and Chemical Engineering, State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials (iChEM), Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province (IKKEM), Xiamen University, Xiamen 361005, China.
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45
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Yang F, Urban RD, Lorenz J, Griebel J, Koohbor N, Rohdenburg M, Knorke H, Fuhrmann D, Charvat A, Abel B, Azov VA, Warneke J. Control of Intermediates and Products by Combining Droplet Reactions and Ion Soft-Landing. Angew Chem Int Ed Engl 2024; 63:e202314784. [PMID: 37917653 DOI: 10.1002/anie.202314784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 11/01/2023] [Accepted: 11/02/2023] [Indexed: 11/04/2023]
Abstract
Despite being recognized primarily as an analytical technique, mass spectrometry also has a large potential as a synthetic tool, enabling access to advanced synthetic routes by reactions in charged microdroplets or ionic thin layers. Such reactions are special and proceed primarily at surfaces of droplets and thin layers. Partial solvation of the reactants is usually considered to play an important role for reducing the activation barrier, but many mechanistic details still need to be clarified. In our study, we showcase the synergy between two sequentially applied "preparative mass spectrometry" methods: initiating accelerated reactions within microdroplets during electrospray ionization to generate gaseous ionic intermediates in high abundance, which are subsequently mass-selected and soft-landed to react with a provided reagent on a substrate. This allows the generation of products at a nanomolar scale, amenable to further characterization. In this proof-of-concept study, the contrasting reaction pathways between intrinsically neutral and pre-charged reagents, respectively, both in microdroplets and in layers generated by ion soft-landing are investigated. This provides new insights into the role of partially solvated reagents at microdroplet surfaces for increased reaction rates. Additionally, further insights into reactions of ions of the same polarity under various conditions is obtained.
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Affiliation(s)
- Fangshun Yang
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
| | - Raphael D Urban
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
| | - Jonas Lorenz
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
| | - Jan Griebel
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
| | - Nima Koohbor
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
| | - Markus Rohdenburg
- Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, University Leipzig, Linnéstrasse 2, 04103, Leipzig, Germany
| | - Harald Knorke
- Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, University Leipzig, Linnéstrasse 2, 04103, Leipzig, Germany
| | - Daniel Fuhrmann
- Institute for Inorganic Chemistry, University Leipzig, Johannisallee 29, 04103, Leipzig, Germany
| | - Ales Charvat
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
- Institute of Chemical Technology, University Leipzig, 04103, Leipzig, Germany
| | - Bernd Abel
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
- Institute of Chemical Technology, University Leipzig, 04103, Leipzig, Germany
| | - Vladimir A Azov
- Department of Chemistry, University of the Free State, 9300, Bloemfontein, South Africa
| | - Jonas Warneke
- Leibniz Institute of Surface Engineering (IOM), Permoserstrasse 15, 04318, Leipzig, Germany
- Wilhelm-Ostwald-Institute for Physical and Theoretical Chemistry, University Leipzig, Linnéstrasse 2, 04103, Leipzig, Germany
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46
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Qiu L, Cooks RG. Oxazolone mediated peptide chain extension and homochirality in aqueous microdroplets. Proc Natl Acad Sci U S A 2024; 121:e2309360120. [PMID: 38165938 PMCID: PMC10786291 DOI: 10.1073/pnas.2309360120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Accepted: 11/20/2023] [Indexed: 01/04/2024] Open
Abstract
Peptide formation from amino acids is thermodynamically unfavorable but a recent study provided evidence that the reaction occurs at the air/solution interfaces of aqueous microdroplets. Here, we show that i) the suggested amino acid complex in microdroplets undergoes dehydration to form oxazolone; ii) addition of water to oxazolone forms the dipeptide; and iii) reaction of oxazolone with other amino acids forms tripeptides. Furthermore, the chirality of the reacting amino acids is preserved in the oxazolone product, and strong chiral selectivity is observed when converting the oxazolone to tripeptide. This last fact ensures that optically impure amino acids will undergo chain extension to generate pure homochiral peptides. Peptide formation in bulk by wet-dry cycling shares a common pathway with the microdroplet reaction, both involving the oxazolone intermediate.
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Affiliation(s)
- Lingqi Qiu
- Department of Chemistry, Purdue University, West Lafayette, IN47907
| | - R. Graham Cooks
- Department of Chemistry, Purdue University, West Lafayette, IN47907
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47
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Song X, Basheer C, Zare RN. Water Microdroplets-Initiated Methane Oxidation. J Am Chem Soc 2023; 145:27198-27204. [PMID: 38054976 DOI: 10.1021/jacs.3c08643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
The special redox reactivity of water microdroplets causes "mild ignition" of methane gas to form methane oxygenates. The C(sp3)-H bond of methane can be activated by the hydroxyl radical (OH·) or the hydrogen radical (H·) across the air-water interface (AWI) of microdroplets to generate the methyl radical (CH3·). Once CH3· is formed, it undergoes free-radical reactions with O2 in the air, excessive OH· and H· across the AWI, and H2O2 present at the AWI and generated CH3· itself to produce methanol and other species. Production of the methanol and other oxygenates was confirmed by gas chromatography, mass spectrometry, and 1H- and 13C-nuclear magnetic resonance. Formic acid, acetic acid, ethanol, carbon dioxide, and methyl peroxide were also detected as methane oxidation byproducts. This water microdroplet-initiated oxidation process can be further enhanced under ultrasonication to yield 2.66 ± 0.77 mM methanol conversion from the methane gas in a single spray run for 30 min, with a selectivity of 19.2% compared with all other oxygenated species.
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Affiliation(s)
- Xiaowei Song
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Chanbasha Basheer
- Chemistry Department, King Fahd University of Petroleum and Minerals, Dhahran 31261, Saudi Arabia
| | - Richard N Zare
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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48
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Li K, You W, Wang W, Gong K, Liu Y, Wang L, Ge Q, Ruan X, Ao J, Ji M, Zhang L. Significantly Accelerated Photochemical Perfluorooctanoic Acid Decomposition at the Air-Water Interface of Microdroplets. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:21448-21458. [PMID: 38047763 DOI: 10.1021/acs.est.3c05470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/05/2023]
Abstract
The efficient elimination of per- and polyfluoroalkyl substances (PFASs) from the environment remains a huge challenge and requires advanced technologies. Herein, we demonstrate that perfluorooctanoic acid (PFOA) photochemical decomposition could be significantly accelerated by simply carrying out this process in microdroplets. The almost complete removal of 100 and 500 μg/L PFOA was observed after 20 min of irradiation in microdroplets, while this was achieved after about 2 h in the corresponding bulk phase counterpart. To better compare the defluorination ratio, 10 mg/L PFOA was used typically, and the defluorination rates in microdroplets were tens of times faster than that in the bulk phase reaction system. The high performances in actual water matrices, universality, and scale-up applicability were demonstrated as well. We revealed in-depth that the great acceleration is due to the abundance of the air-water interface in microdroplets, where the reactants concentration enrichment, ultrahigh interfacial electric field, and partial solvation effects synergistically promoted photoreactions responsible for PFOA decomposition, as evidenced by simulated Raman scattering microscopy imaging, vibrational Stark effect measurement, and DFT calculation. This study provides an effective approach and highlights the important roles of air-water interface of microdroplets in PFASs treatment.
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Affiliation(s)
- Kejian Li
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan University, Shanghai 200433, People's Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China
| | - Wenbo You
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Wei Wang
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Kedong Gong
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Yangyang Liu
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Longqian Wang
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Qiuyue Ge
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Xuejun Ruan
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
| | - Jianpeng Ao
- State Key Laboratory of Surface Physics, Department of Physics, Fudan University, Shanghai 200433, People's Republic of China
| | - Minbiao Ji
- State Key Laboratory of Surface Physics, Department of Physics, Fudan University, Shanghai 200433, People's Republic of China
| | - Liwu Zhang
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, People's Republic of China
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Fudan University, Shanghai 200433, People's Republic of China
- Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, People's Republic of China
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49
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Song Z, Liang C, Gong K, Zhao S, Yuan X, Zhang X, Xie J. Harnessing the High Interfacial Electric Fields on Water Microdroplets to Accelerate Menshutkin Reactions. J Am Chem Soc 2023; 145:26003-26008. [PMID: 38011046 DOI: 10.1021/jacs.3c11650] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023]
Abstract
Even though it is still an emerging field, the application of a high external electric field (EEF) as a green and efficient catalyst in synthetic chemistry has recently received significant attention for the ability to deliver remarkable control of reaction selectivity and acceleration of reaction rates. Here, we extend the application of the EEF to Menshutkin reactions by taking advantage of the spontaneous high electric field at the air-water interfaces of sprayed water microdroplets. Experimentally, a series of Menshutkin reactions were accelerated by 7 orders of magnitude. Theoretically, both density functional theory calculations and ab initio molecular dynamics simulations predict that the reaction barrier decreases significantly in the presence of oriented external electric fields, thereby supporting the notion that the electric fields in the water droplets are responsible for the catalysis. In addition, the ordered solvent and reactant molecules oriented by the electric field alleviate the steric effect of solvents and increase the successful collision rates, thus facilitating faster nucleophilic attack. The success of Menshutkin reactions in this study showcases the great potential of microdroplet chemistry for green synthesis.
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Affiliation(s)
- Zhexuan Song
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Chiyu Liang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
- Beijing National Laboratory for Molecular Sciences, Beijing 100190, China
| | - Ke Gong
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Supin Zhao
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
| | - Xu Yuan
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
- Beijing National Laboratory for Molecular Sciences, Beijing 100190, China
| | - Xinxing Zhang
- College of Chemistry, Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Renewable Energy Conversion and Storage Centre, Tianjin Key Laboratory of Biosensing and Molecular Recognition, Frontiers Science Centre for New Organic Matter, Nankai University, Tianjin 300071, China
- Beijing National Laboratory for Molecular Sciences, Beijing 100190, China
| | - Jing Xie
- Key Laboratory of Cluster Science of Ministry of Education, Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing 100081, China
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50
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Salvitti C, de Petris G, Troiani A, Managò M, Di Noi A, Ricci A, Pepi F. Sulfuric Acid Catalyzed Esterification of Amino Acids in Thin Film. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2023; 34:2748-2754. [PMID: 37904271 DOI: 10.1021/jasms.3c00284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2023]
Abstract
The esterification reaction of different amino acids with methanol catalyzed by H2SO4 was first studied in the small volume of thin films generated by ESI microdroplet deposition. The reaction is promoted by the pneumatic spray of the ESI source and reaches its maximum efficiency at a thin film temperature of 70 °C. Selective esterification of the COOH moiety was demonstrated. Microdroplet size and thin film volume and lifetime are critical parameters that influenced the reaction outcome. As expected, l-tyrosine and l-phenylalanine having aromatic side chain substituents were the most reactive amino acids, reaching absolute yields of around 40-50%. The amino acid esterification catalyzed by H2SO4 in a thin film occurs under synthetic conditions in which the same reaction in the bulk is not observed.
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Affiliation(s)
- Chiara Salvitti
- "Sapienza" University of Rome, Department of Chemistry and Drug Technologies P.le Aldo Moro 5, 00185 Rome, Italy
| | - Giulia de Petris
- "Sapienza" University of Rome, Department of Chemistry and Drug Technologies P.le Aldo Moro 5, 00185 Rome, Italy
| | - Anna Troiani
- "Sapienza" University of Rome, Department of Chemistry and Drug Technologies P.le Aldo Moro 5, 00185 Rome, Italy
| | - Marta Managò
- "Sapienza" University of Rome, Department of Chemistry and Drug Technologies P.le Aldo Moro 5, 00185 Rome, Italy
| | - Alessia Di Noi
- "Sapienza" University of Rome, Department of Chemistry and Drug Technologies P.le Aldo Moro 5, 00185 Rome, Italy
| | - Andreina Ricci
- Department of Mathematics and Physics, University of Campania L. Vanvitelli, Viale Lincoln 5, 81100, Caserta, Italy
| | - Federico Pepi
- "Sapienza" University of Rome, Department of Chemistry and Drug Technologies P.le Aldo Moro 5, 00185 Rome, Italy
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