1
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Liu Z, Lin L, Li T, Premadasa UI, Hong K, Ma YZ, Sacci RL, Katsaras J, Carrillo JM, Doughty B, Collier CP. Physicochemical control of solvation and molecular assembly of charged amphiphilic oligomers at air-aqueous interfaces. J Colloid Interface Sci 2024; 669:552-560. [PMID: 38729003 DOI: 10.1016/j.jcis.2024.05.008] [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: 11/16/2023] [Revised: 03/07/2024] [Accepted: 05/02/2024] [Indexed: 05/12/2024]
Abstract
HYPOTHESIS Understanding the rules that control the assembly of nanostructured soft materials at interfaces is central to many applications. We hypothesize that electrolytes can be used to alter the hydration shell of amphiphilic oligomers at the air-aqueous interface of Langmuir films, thereby providing a means to control the formation of emergent nanostructures. EXPERIMENTS Three representative salts - (NaF, NaCl, NaSCN) were studied for mediating the self-assembly of oligodimethylsiloxane methylimidazolium (ODMS-MIM+) amphiphiles in Langmuir films. The effects of the different salts on the nanostructure assembly of these films were probed using vibrational sum frequency generation (SFG) spectroscopy and Langmuir trough techniques. Experimental data were supported by atomistic molecular dynamic simulations. FINDINGS Langmuir trough surface pressure - area isotherms suggested a surprising effect on oligomer assembly, whereby the presence of anions affects the stability of the interfacial layer irrespective of their surface propensities. In contrast, SFG results implied a strong anion effect that parallels the surface activity of anions. These seemingly contradictory trends are explained by anion driven tail dehydration resulting in increasingly heterogeneous systems with entangled ODMS tails and appreciable anion penetration into the complex interfacial layer comprised of headgroups, tails, and interfacial water molecules. These findings provide physical and chemical insight for tuning a wide range of interfacial assemblies.
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Affiliation(s)
- Zening Liu
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Lu Lin
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Tianyu Li
- Department of Materials Science and Engineering, University of Tennessee, Knoxville, TN 37996, United States
| | - Uvinduni I Premadasa
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Kunlun Hong
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Ying-Zhong Ma
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Robert L Sacci
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - John Katsaras
- Neutron Scattering Division and Shull Wollan Center, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States; Shull Wollan Center, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States
| | - Jan-Michael Carrillo
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States.
| | - Benjamin Doughty
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States.
| | - C Patrick Collier
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37831, United States.
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2
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Seki T, Yu CC, Chiang KY, Yu X, Sun S, Bonn M, Nagata Y. Spontaneous Appearance of Triiodide Covering the Topmost Layer of the Iodide Solution Interface Without Photo-Oxidation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:3830-3837. [PMID: 38353041 PMCID: PMC10902846 DOI: 10.1021/acs.est.3c08243] [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: 02/28/2024]
Abstract
Ions containing iodine atoms at the vapor-aqueous solution interfaces critically affect aerosol growth and atmospheric chemistry due to their complex chemical nature and multivalency. While the surface propensity of iodide ions has been intensely discussed in the context of the Hofmeister series, the stability of various ions containing iodine atoms at the vapor-water interface has been debated. Here, we combine surface-specific sum-frequency generation (SFG) vibrational spectroscopy with ab initio molecular dynamics simulations to examine the extent to which iodide ions cover the aqueous surface. The SFG probe of the free O-D stretch mode of heavy water indicates that the free O-D group density decreases drastically at the interface when the bulk NaI concentration exceeds ∼2 M. The decrease in the free O-D group density is attributed to the spontaneous appearance of triiodide that covers the topmost interface rather than to the surface adsorption of iodide. This finding demonstrates that iodide is not surface-active, yet the highly surface-active triiodide is generated spontaneously at the water-air interface, even under dark and oxygen-free conditions. Our study provides an important first step toward clarifying iodine chemistry and pathways for aerosol formation.
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Affiliation(s)
- Takakazu Seki
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Graduate School of Science and Technology, Hirosaki University, Hirosaki, Aomori 036-8561, Japan
| | - Chun-Chieh Yu
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Kuo-Yang Chiang
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Xiaoqing Yu
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Shumei Sun
- Department of Physics, Applied Optics Beijing Area Major Laboratory, Beijing Normal University, Beijing 100875, China
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Yuki Nagata
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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3
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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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4
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Rana B, Fairhurst DJ, Jena KC. Investigation of Water Evaporation Process at Air/Water Interface using Hofmeister Ions. J Am Chem Soc 2022; 144:17832-17840. [PMID: 36131621 DOI: 10.1021/jacs.2c05837] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Evaporation is an interfacial phenomenon in which a water molecule breaks the intermolecular hydrogen (H-) bonds and enters the vapor phase. However, a detailed demonstration of the role of interfacial water structure in the evaporation process is still lacking. Here, we purposefully perturb the H-bonding environment at the air/water interface by introducing kosmotropic (HPO4-2, SO4-2, and CO3-2) and chaotropic ions (NO3- and I-) to determine their influence on the evaporation process. Using time-resolved interferometry on aqueous salt droplets, we found that kosmotropes reduce evaporation, whereas chaotropes accelerate the evaporation process, following the Hofmeister series: HPO4-2 < SO4-2 < CO3-2 < Cl- < NO3- < I-. To extract deeper molecular-level insights into the observed Hofmeister trend in the evaporation rates, we investigated the air/water interface in the presence of ions using surface-specific sum frequency generation (SFG) vibrational spectroscopy. The SFG vibrational spectra reveal the significant impact of ions on the strength of the H-bonding environment and the orientation of free OH oscillators from ∼36.2 to 48.4° at the air/water interface, where both the effects follow the Hofmeister series. It is established that the slow evaporating water molecules experience a strong H-bonding environment with free OH oscillators tilted away from the surface normal in the presence of kosmotropes. In contrast, the fast evaporating water molecules experience a weak H-bonding environment with free OH oscillators tilted toward the surface normal in the presence of chaotropes at the air/water interface. Our experimental outcomes showcase the complex bonding environment of interfacial water molecules and their decisive role in the evaporation process.
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Affiliation(s)
- Bhawna Rana
- Department of Physics, Indian Institute of Technology Ropar, Rupnagar, Punjab 140001, India
| | - David J Fairhurst
- Department of Physics and Mathematics, School of Science and Technology, Nottingham Trent University, Clifton Campus, Nottingham NG11 8NS, United Kingdom
| | - Kailash C Jena
- Department of Physics, Indian Institute of Technology Ropar, Rupnagar, Punjab 140001, India.,Department of Biomedical Engineering, Indian Institute of Technology Ropar, Rupnagar, Punjab 140001, India
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5
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Yu CC, Seki T, Chiang KY, Tang F, Sun S, Bonn M, Nagata Y. Polarization-Dependent Heterodyne-Detected Sum-Frequency Generation Spectroscopy as a Tool to Explore Surface Molecular Orientation and Ångström-Scale Depth Profiling. J Phys Chem B 2022; 126:6113-6124. [PMID: 35849538 PMCID: PMC9421650 DOI: 10.1021/acs.jpcb.2c02178] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
![]()
Sum-frequency generation (SFG) spectroscopy provides
a unique optical
probe for interfacial molecules with interface-specificity and molecular
specificity. SFG measurements can be further carried out at different
polarization combinations, but the target of the polarization-dependent
SFG is conventionally limited to investigating the molecular orientation.
Here, we explore the possibility of polarization-dependent SFG (PD-SFG)
measurements with heterodyne detection (HD-PD-SFG). We stress that
HD-PD-SFG enables accurate determination of the peak amplitude, a
key factor of the PD-SFG data. Subsequently, we outline that HD-PD-SFG
can be used not only for estimating the molecular orientation but
also for investigating the interfacial dielectric profile and studying
the depth profile of molecules. We further illustrate the variety
of combined simulation and PD-SFG studies.
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Affiliation(s)
- Chun-Chieh Yu
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Takakazu Seki
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Kuo-Yang Chiang
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Fujie Tang
- Department of Physics, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Shumei Sun
- Department of Physics and Applied Optics Beijing Area Major Laboratory, Beijing Normal University, Beijing 100875, China
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Yuki Nagata
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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6
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Lin L, Chowdhury AU, Ma YZ, Sacci RL, Katsaras J, Hong K, Collier CP, Carrillo JMY, Doughty B. Ion Pairing and Molecular Orientation at Liquid/Liquid Interfaces: Self-Assembly and Function. J Phys Chem B 2022; 126:2316-2323. [PMID: 35289625 DOI: 10.1021/acs.jpcb.2c01148] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Molecular orientation plays a pivotal role in defining the functionality and chemistry of interfaces, yet accurate measurements probing this important feature are few, due, in part, to technical and analytical limitations in extracting information from molecular monolayers. For example, buried liquid/liquid interfaces, where a complex and poorly understood balance of inter- and intramolecular interactions impart structural constraints that facilitate the formation of supramolecular assemblies capable of new functions, are difficult to probe experimentally. Here, we use vibrational sum-frequency generation spectroscopy, numerical polarization analysis, and atomistic molecular dynamics simulations to probe molecular orientations at buried oil/aqueous interfaces decorated with amphiphilic oligomers. We show that the orientation of self-assembled oligomers changes upon the addition of salts in the aqueous phase. The evolution of these structures can be described by competitive ion effects in the aqueous phase altering the orientations of the tails extending into the oil phase. These specific anionic effects occur via interfacial ion pairing and associated changes in interfacial solvation and hydrogen-bonding networks. These findings provide more quantitative insight into orientational changes encountered during self-assembly and pave the way for the design of functional interfaces for chemical separations, neuromorphic computing applications, and related biomimetic systems.
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Affiliation(s)
- Lu Lin
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Azhad U Chowdhury
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Ying-Zhong Ma
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Robert L Sacci
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - John Katsaras
- Labs and Soft Matter Group, Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.,Shull Wollan Center, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Kunlun Hong
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - C Patrick Collier
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Jan-Michael Y Carrillo
- Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Benjamin Doughty
- Chemical Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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7
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Yu CC, Imoto S, Seki T, Chiang KY, Sun S, Bonn M, Nagata Y. Accurate molecular orientation at interfaces determined by multimode polarization-dependent heterodyne-detected sum-frequency generation spectroscopy via multidimensional orientational distribution function. J Chem Phys 2022; 156:094703. [DOI: 10.1063/5.0081209] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Many essential processes occur at soft interfaces, from chemical reactions on aqueous aerosols in the atmosphere to biochemical recognition and binding at the surface of cell membranes. The spatial arrangement of molecules specifically at these interfaces is crucial for many of such processes. The accurate determination of the interfacial molecular orientation has been challenging due to the low number of molecules at interfaces and the ambiguity of their orientational distribution. Here, we combine phase- and polarization-resolved sum-frequency generation (SFG) spectroscopy to obtain the molecular orientation at the interface. We extend an exponentially decaying orientational distribution to multiple dimensions, which, in conjunction with multiple SFG datasets obtained from the different vibrational modes, allows us to determine the molecular orientation. We apply this new approach to formic acid molecules at the air–water interface. The inferred orientation of formic acid agrees very well with ab initio molecular dynamics data. The phase-resolved SFG multimode analysis scheme using the multidimensional orientational distribution thus provides a universal approach for obtaining the interfacial molecular orientation.
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Affiliation(s)
- Chun-Chieh Yu
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Sho Imoto
- Analysis Technology Center, Fujifilm R&D, 210 Nakanuma, Minamiashigara, Kanagawa 250-0123, Japan
| | - Takakazu Seki
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Kuo-Yang Chiang
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Shumei Sun
- Applied Optics Beijing Area Major Laboratory, Department of Physics, Beijing Normal University, 100875 Beijing, China
| | - Mischa Bonn
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Yuki Nagata
- Molecular Spectroscopy Department, Max Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
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8
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Li X, Pramhaas V, Rameshan C, Blaha P, Rupprechter G. Coverage-Induced Orientation Change: CO on Ir(111) Monitored by Polarization-Dependent Sum Frequency Generation Spectroscopy and Density Functional Theory. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2020; 124:18102-18111. [PMID: 32855760 PMCID: PMC7444014 DOI: 10.1021/acs.jpcc.0c04986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 07/21/2020] [Indexed: 05/16/2023]
Abstract
Polarization-dependent sum frequency generation (SFG) spectroscopy was applied to study the adsorption of carbon monoxide (CO) on the well-ordered (annealed) Ir(111) single-crystal surface at various CO coverages. Coverage was adjusted by varying the substrate temperature (300-575 K) and/or gas pressure (10-7 to 1.0 mbar). Under all conditions investigated, only a single absorption band at 2038-2094 cm-1 was observed, characteristic of linearly bonded (on-top) CO. Using different polarizations, PPP and SSP spectra were acquired with a high signal-to-noise ratio, whereby tilt angles of CO on Ir(111) could be determined for the first time by SFG. It was found that not only the vibrational frequency of on-top CO but also the tilt angle was strongly coverage-dependent. The higher the coverage was, the larger the vibrational frequency and the tilt angle were. At about 0.7 ML coverage, a CO tilt angle of at least 20° was observed, which is in good agreement with density functional theory (DFT) calculations. In addition, the molecular hyperpolarizability ratio (R) of CO (at 0.13 ML in UHV) was determined to be 0.08. Based on the combined SFG/DFT results, it may change to 0.29 at 0.77 ML coverage.
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9
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Hao H, Xie Q, Ai J, Wang Y, Bian H. Specific counter-cation effect on the molecular orientation of thiocyanate anions at the aqueous solution interface. Phys Chem Chem Phys 2020; 22:10106-10115. [PMID: 32342973 DOI: 10.1039/d0cp00974a] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Understanding the interfacial structure of aqueous electrolyte solutions is important and relevant to a wide range of systems, ranging from atmospheric aerosols to electrochemistry, and biological environments. Though significant efforts have been made to unravel the interfacial structure of water molecules, the structure and dynamics of ions at the interface have not yet been fully elucidated. Here, the interfacial structure of the aqueous solution was investigated directly by monitoring the thiocyanate (SCN-) anions using surface-specific sum frequency generation (SFG) vibrational spectroscopy. The molecular orientation of the SCN- anions and their adsorption behavior at the air/water interface were systematically determined by quantitative polarization analysis. The transition dipole of the CN stretching of the SCN- anion is oriented around 44° from the surface normal of the NaSCN aqueous solution surface and remained unchanged with the bulk concentration varying from 1 mol kg-1 to 13 mol kg-1. The free energy of adsorption of SCN- anions at the air/water interface was determined to be -1.53 ± 0.04 kcal mol-1. Furthermore, a new SFG peak positioned at 2080 cm-1 in the ppp polarization combination was observed at the air/15.0 mol kg-1 NaSCN aqueous solution interface for the first time. Concentration-dependent SFG analysis and density functional theory (DFT) calculation further revealed that the SCN- anions form an ion clustering structure at the air/water interface. The subtle and specific Na+ and K+ counter-cation effects on the interfacial structure of the SCN- anions at the aqueous solution interface were also observed, which showed that ion cooperativity plays an important role in affecting the interfacial structure of ions at the air/water interface. The results are expected to yield significant insights into the understanding of the structure of aqueous solution surfaces and the molecular level mechanism of the cationic Hofmeister effect.
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Affiliation(s)
- Hongxing Hao
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China.
| | - Qing Xie
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China.
| | - Jingwen Ai
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China.
| | - Yuan Wang
- Institute of Science and Technology, University of Sanya, Sanya, Hainan 572022, China
| | - Hongtao Bian
- Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shaanxi Normal University, Xi'an, 710119, China.
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10
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Tang F, Ohto T, Sun S, Rouxel JR, Imoto S, Backus EHG, Mukamel S, Bonn M, Nagata Y. Molecular Structure and Modeling of Water-Air and Ice-Air Interfaces Monitored by Sum-Frequency Generation. Chem Rev 2020; 120:3633-3667. [PMID: 32141737 PMCID: PMC7181271 DOI: 10.1021/acs.chemrev.9b00512] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2019] [Indexed: 12/26/2022]
Abstract
From a glass of water to glaciers in Antarctica, water-air and ice-air interfaces are abundant on Earth. Molecular-level structure and dynamics at these interfaces are key for understanding many chemical/physical/atmospheric processes including the slipperiness of ice surfaces, the surface tension of water, and evaporation/sublimation of water. Sum-frequency generation (SFG) spectroscopy is a powerful tool to probe the molecular-level structure of these interfaces because SFG can specifically probe the topmost interfacial water molecules separately from the bulk and is sensitive to molecular conformation. Nevertheless, experimental SFG has several limitations. For example, SFG cannot provide information on the depth of the interface and how the orientation of the molecules varies with distance from the surface. By combining the SFG spectroscopy with simulation techniques, one can directly compare the experimental data with the simulated SFG spectra, allowing us to unveil the molecular-level structure of water-air and ice-air interfaces. Here, we present an overview of the different simulation protocols available for SFG spectra calculations. We systematically compare the SFG spectra computed with different approaches, revealing the advantages and disadvantages of the different methods. Furthermore, we account for the findings through combined SFG experiments and simulations and provide future challenges for SFG experiments and simulations at different aqueous interfaces.
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Affiliation(s)
- Fujie Tang
- Max
Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- Department
of Physics, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Tatsuhiko Ohto
- Graduate
School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan
| | - Shumei Sun
- Max
Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- Department
of Physical Chemistry, University of Vienna, Währinger Strasse 42, 1090 Vienna, Austria
| | - Jérémy R. Rouxel
- Department
of Chemistry and Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-2025, United States
| | - Sho Imoto
- Max
Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Ellen H. G. Backus
- Max
Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- Department
of Physical Chemistry, University of Vienna, Währinger Strasse 42, 1090 Vienna, Austria
| | - Shaul Mukamel
- Department
of Chemistry and Department of Physics and Astronomy, University of California, Irvine, Irvine, California 92697-2025, United States
| | - Mischa Bonn
- Max
Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
| | - Yuki Nagata
- Max
Planck Institute for Polymer Research, Ackermannweg 10, Mainz 55128, Germany
- Department
of Physics, State Key Laboratory of Surface Physics and Key Laboratory
of Micro- and Nano-Photonic Structures (MOE), Fudan University, Shanghai 200433, China
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11
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Boily JF, Fu L, Tuladhar A, Lu Z, Legg BA, Wang ZM, Wang H. Hydrogen bonding and molecular orientations across thin water films on sapphire. J Colloid Interface Sci 2019; 555:810-817. [PMID: 31425917 DOI: 10.1016/j.jcis.2019.08.028] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Revised: 08/07/2019] [Accepted: 08/08/2019] [Indexed: 01/28/2023]
Abstract
HYPOTHESIS Water vapor binding to metal oxide surfaces produces thin water films with properties controlled by interactions with surface hydroxo sites. Hydrogen bonding populations vary across films and induce different molecular orientations than at the surface of liquid water. Identifying these differences can open possibilities for tailoring film-mediated catalytic reactions by choice of the supporting metal oxide substrate. EXPERIMENTS The (0001) face of a single sapphire (α-Al2O3) sample exposed to water vapor and the surface of liquid water were probed by polarization dependent Sum Frequency Generation-Vibration Spectroscopy (SFG-VS). Molecular dynamics (MD) provided insight into the hydrogen bond populations and molecular orientations across films and liquid water. FINDINGS SFG-VS revealed a submonolayer film on sapphire exposed to 43% relative humidity (R.H.), and a multilayer film at 78% R.H. Polarization dependent SFG-VS spectra showed that median tilt angles of free OH bonds on the top of films are at ∼43° from the normal of the (0001) face but at 38° on neat liquid water. These values align with MD simulations, which also show that up to 36% of all OH bonds on films are free. This offers new means for understanding how interfacial reactions on sapphire-supported water films could contrast with those involving liquid water.
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Affiliation(s)
| | - Li Fu
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Aashish Tuladhar
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Zhou Lu
- Beijing National Laboratory for Molecular Sciences, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Benjamin A Legg
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Zheming M Wang
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
| | - Hongfei Wang
- Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai 200438, China
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12
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Gan W, Feng RR, Wang HF. Comment on "Orientational Distribution of Free O-H Groups of Interfacial Water is Exponential". PHYSICAL REVIEW LETTERS 2019; 123:099601. [PMID: 31524495 DOI: 10.1103/physrevlett.123.099601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Indexed: 06/10/2023]
Affiliation(s)
- Wei Gan
- State Key Laboratory of Advanced Welding and Joining, and School of Science, Harbin Institute of Technology (Shenzhen), University Town, Shenzhen, Guangdong, 518055, China
| | - Ran-Ran Feng
- Key Laboratory of Microgravity, Beijing Key Laboratory of Engineered Construction and Mechanobiology, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China
| | - Hong-Fei Wang
- Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, 220 Handan Road, Shanghai 200433, China
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13
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Sun S, Tang F, Imoto S, Moberg DR, Ohto T, Paesani F, Bonn M, Backus EHG, Nagata Y. Sun et al. Reply. PHYSICAL REVIEW LETTERS 2019; 123:099602. [PMID: 31524490 DOI: 10.1103/physrevlett.123.099602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Indexed: 06/10/2023]
Affiliation(s)
- Shumei Sun
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Fujie Tang
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- International Center for Quantum Materials, Department of Physics, Peking University, 5 Yiheyuan Road, Haidian, Beijing 100871, China
| | - Sho Imoto
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Daniel R Moberg
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, USA
| | - Tatsuhiko Ohto
- Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan
| | - Francesco Paesani
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, USA
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Ellen H G Backus
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Yuki Nagata
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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14
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Lin L, Husek J, Biswas S, Baumler SM, Adel T, Ng KC, Baker LR, Allen HC. Iron(III) Speciation Observed at Aqueous and Glycerol Surfaces: Vibrational Sum Frequency and X-ray. J Am Chem Soc 2019; 141:13525-13535. [PMID: 31345028 DOI: 10.1021/jacs.9b05231] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Lu Lin
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Jakub Husek
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Somnath Biswas
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Stephen M. Baumler
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Tehseen Adel
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Ka Chon Ng
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - L. Robert Baker
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
| | - Heather C. Allen
- Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States
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15
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Qian Y, Deng GH, Lapp J, Rao Y. Interfaces of Gas-Aerosol Particles: Relative Humidity and Salt Concentration Effects. J Phys Chem A 2019; 123:6304-6312. [PMID: 31253043 DOI: 10.1021/acs.jpca.9b03896] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The growth of aerosol particles is intimately related to chemical reactions in the gas phase and particle phase and at gas-aerosol particle interfaces. While chemical reactions in gas and particle phases are well documented, there is very little information regarding interface-related reactions. The interface of gas-aerosol particles not only facilitates a physical channel for organic species to enter and exit but also provides a necessary lane for culturing chemical reactions. The physical and chemical properties of gas-particle interfaces have not been studied extensively, nor have the reactions occurring at the interfaces been well researched. This is mainly due to the fact that there is a lack of suitable in situ interface-sensitive analytical techniques for direct measurements of interfacial properties. The motivation behind this research is to understand how interfaces play a role in the growth of aerosol particles. We have developed in situ interface-specific second harmonic scattering to examine interfacial behaviors of molecules of aerosol particles under different relative humidity (RH) and salt concentrations. Both the relative humidity and salt concentration can change the particle size and the phase of the aerosol. RH not only varies the concentration of solutes inside aerosol particles but also changes interfacial hydration in local regions. Organic molecules were found to exhibit distinct behaviors at the interfaces and bulk on NaCl particles under different RH levels. Our quantitative analyses showed that the interfacial adsorption free energies remain unchanged while interfacial areas increase as the relative humidity increases. Furthermore, the surface tension of NaCl particles decreases as the RH increases. Our experimental findings from the novel nonlinear optical scattering technique stress the importance of interfacial water behaviors on aerosol particles in the atmosphere.
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Affiliation(s)
- Yuqin Qian
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Gang-Hua Deng
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Jordan Lapp
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
| | - Yi Rao
- Department of Chemistry and Biochemistry , Utah State University , Logan , Utah 84322 , United States
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16
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Dodia M, Ohto T, Imoto S, Nagata Y. Structure and Dynamics of Water at the Water-Air Interface Using First-Principles Molecular Dynamics Simulations. II. NonLocal vs Empirical van der Waals Corrections. J Chem Theory Comput 2019; 15:3836-3843. [PMID: 31074989 PMCID: PMC6750744 DOI: 10.1021/acs.jctc.9b00253] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
![]()
van der Waals (vdW) correction schemes
have been recognized to
be essential for an accurate description of liquid water in first-principles
molecular dynamics simulation. The description of the structure and
dynamics of water is governed by the type of the vdW corrections.
So far, two vdW correction schemes have been often used: empirical
vdW corrections and nonlocal vdW corrections. In this paper, we assess
the influence of the empirical vs nonlocal vdW correction schemes
on the structure and dynamics of water at the water–air interface.
Since the structure of water at the water–air interface is
established by a delicate balance of hydrogen bond formation and breaking,
the simulation at the water–air interface provides a unique
platform to testify as to the heterogeneous interaction of water.
We used the metrics [Ohto et al. J. Chem. Theory Comput., 2019, 15, 595−60230468702] which
are directly connected with the sum-frequency generation spectroscopic
measurement. We find that the overall performance of nonlocal vdW
methods is either similar or worse compared to the empirical vdW methods.
We also investigated the performance of the optB88-DRSLL functional,
which showed slightly less accuracy than the revPBE-D3 method. We
conclude that the revPBE-D3 method shows the best performance for
describing the interfacial water.
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Affiliation(s)
- Mayank Dodia
- Max Planck Institute for Polymer Research, Ackermannweg 10 , 55128 Mainz , Germany
| | - Tatsuhiko Ohto
- Graduate School of Engineering Science , Osaka University , 1-3 Machikaneyama , Toyonaka, Osaka 560-8531 , Japan
| | - Sho Imoto
- Max Planck Institute for Polymer Research, Ackermannweg 10 , 55128 Mainz , Germany
| | - Yuki Nagata
- Max Planck Institute for Polymer Research, Ackermannweg 10 , 55128 Mainz , Germany
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17
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Sun S, Tang F, Imoto S, Moberg DR, Ohto T, Paesani F, Bonn M, Backus EHG, Nagata Y. Orientational Distribution of Free O-H Groups of Interfacial Water is Exponential. PHYSICAL REVIEW LETTERS 2018; 121:246101. [PMID: 30608741 DOI: 10.1103/physrevlett.121.246101] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Revised: 11/09/2018] [Indexed: 06/09/2023]
Abstract
The orientational distribution of free O-H (O-D) groups at the H_{2}O- (D_{2}O-)air interface is investigated using combined molecular dynamics (MD) simulations and sum-frequency generation (SFG) experiments. The average angle of the free O-H groups, relative to the surface normal, is found to be ∼63°, substantially larger than previous estimates of 30°-40°. This discrepancy can be traced to erroneously assumed Gaussian or stepwise orientational distributions of free O-H groups. Instead, the MD simulation and SFG measurement reveal a broad and exponentially decaying orientational distribution. The broad orientational distribution indicates the presence of the free O-H group pointing down to the bulk. We ascribe the origin of such free O-H groups to the presence of capillary waves on the water surface.
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Affiliation(s)
- Shumei Sun
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Fujie Tang
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- International Center for Quantum Materials, School of Physics, Peking University, 5 Yiheyuan Road, Haidian, Beijing 100871, China
| | - Sho Imoto
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Daniel R Moberg
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, USA
| | - Tatsuhiko Ohto
- Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan
| | - Francesco Paesani
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093, USA
| | - Mischa Bonn
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Ellen H G Backus
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Yuki Nagata
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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18
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Ohto T, Dodia M, Imoto S, Nagata Y. Structure and Dynamics of Water at the Water–Air Interface Using First-Principles Molecular Dynamics Simulations within Generalized Gradient Approximation. J Chem Theory Comput 2018; 15:595-602. [DOI: 10.1021/acs.jctc.8b00567] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Tatsuhiko Ohto
- Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan
| | - Mayank Dodia
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Sho Imoto
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Yuki Nagata
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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19
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Li X, Roiaz M, Pramhaas V, Rameshan C, Rupprechter G. Polarization-Dependent SFG Spectroscopy of Near Ambient Pressure CO Adsorption on Pt(111) and Pd(111) Revisited. Top Catal 2018; 61:751-762. [PMID: 29950796 PMCID: PMC6010505 DOI: 10.1007/s11244-018-0949-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Polarization-dependent sum frequency generation (SFG) vibrational spectroscopy was employed to examine CO overlayers on Pt(111) and Pd(111) single crystal surfaces at room temperature. Utilizing different polarization combinations (SSP and PPP) of the visible and SFG light allows to determine the molecular orientation (tilt angle) of interface molecules but the analysis of the measured \documentclass[12pt]{minimal}
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\begin{document}$$I_{\text{ppp}}/I_{\text{ssp}}$$\end{document}Ippp/Issp is involved and requires a proper optical interface model. For CO/Pt(111), the hyperpolarizability ratio \documentclass[12pt]{minimal}
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\begin{document}$$\left( {R={\beta _{aac}}/{\beta _{ccc}}={\beta _{bbc}}/{\beta _{ccc}}} \right)$$\end{document}R=βaac/βccc=βbbc/βccc is not exactly known and varying R in the range 0.1–0.5 yields tilt angles of 40°–0°, respectively. Based on the known perpendicular adsorption of CO on Pt, an exact R-value of 0.49 was determined. Polarization-dependent SFG spectra in the pressure range 10−4 to 36 mbar did not indicate any change of the tilt angle of adsorbed CO. Modeling also indicated a strong dependence of \documentclass[12pt]{minimal}
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\begin{document}$${I_{{\text{ppp}}}}/{I_{{\text{ssp}}}}$$\end{document}Ippp/Issp on the incidence angles of visible and IR laser beams. Complementing previous low temperature/low pressure data, room temperature CO adsorption on Pd(111) was examined from 10−6 to 250 mbar. The absolute PPP and SSP spectral intensities on Pt and Pd were simulated, as well as the expected \documentclass[12pt]{minimal}
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\begin{document}$${I_{{\text{ppp}}}}/{I_{{\text{ssp}}}}$$\end{document}Ippp/Issp ratios. Although CO on Pt and Pd should exhibit similar intensities (at high CO coverage), the higher \documentclass[12pt]{minimal}
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\begin{document}$${I_{{\text{ppp}}}}/{I_{{\text{ssp}}}}$$\end{document}Ippp/Issp ratio for Pd (48 vs. 27 on Pt) renders the detection of adsorbed CO in SSP spectra difficult. The presence or absence of CO species in SSP spectra can thus not simply be correlated to tilted or perpendicular CO molecules, respectively. Careful modeling, including not only molecular and interface properties, but also the experimental configuration (incidence angles), is certainly required even for seemingly simple adsorbate–substrate systems.
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Affiliation(s)
- Xia Li
- Institute of Materials Chemistry, TU Wien, 1060 Vienna, Austria
| | - Matteo Roiaz
- Institute of Materials Chemistry, TU Wien, 1060 Vienna, Austria
| | - Verena Pramhaas
- Institute of Materials Chemistry, TU Wien, 1060 Vienna, Austria
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20
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Tan J, Luo Y, Ye S. A Highly Sensitive Femtosecond Time-Resolved Sum Frequency Generation Vibrational Spectroscopy System with Simultaneous Measurement of Multiple Polarization Combinations. CHINESE J CHEM PHYS 2017. [DOI: 10.1063/1674-0068/30/cjcp1706114] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Junjun Tan
- Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Yi Luo
- Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Shuji Ye
- Hefei National Laboratory for Physical Sciences at the Microscale, and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
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21
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Tang F, Ohto T, Hasegawa T, Xie WJ, Xu L, Bonn M, Nagata Y. Definition of Free O–H Groups of Water at the Air–Water Interface. J Chem Theory Comput 2017; 14:357-364. [DOI: 10.1021/acs.jctc.7b00566] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Fujie Tang
- International
Center for Quantum Materials, School of Physics, Peking University, 5
Yiheyuan Road, Haidian, Beijing 100871, China
- Max Planck Institute
for Polymer Research, Ackermannweg
10, D-55128 Mainz, Germany
| | - Tatsuhiko Ohto
- Graduate
School of Engineering Science, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan
| | - Taisuke Hasegawa
- Max Planck Institute
for Polymer Research, Ackermannweg
10, D-55128 Mainz, Germany
- Department
of Chemistry, Graduate School of Science, Kyoto University, Sakyoku, Kyoto 606-8502, Japan
| | - Wen Jun Xie
- Max Planck Institute
for Polymer Research, Ackermannweg
10, D-55128 Mainz, Germany
- College
of Chemistry and Molecular Engineering, Peking University, 5
Yiheyuan Road, Haidian, Beijing 100871, China
| | - Limei Xu
- International
Center for Quantum Materials, School of Physics, Peking University, 5
Yiheyuan Road, Haidian, Beijing 100871, China
- Collaborative Innovation
Center of Quantum Matter, Beijing 100871, China
| | - Mischa Bonn
- Max Planck Institute
for Polymer Research, Ackermannweg
10, D-55128 Mainz, Germany
| | - Yuki Nagata
- Max Planck Institute
for Polymer Research, Ackermannweg
10, D-55128 Mainz, Germany
- Institute for
Molecular Science, Myodaiji, Okazaki, Aichi 444-8585, Japan
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22
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23
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Li X, Feng RJ, Wang JJ, Zhang Z, Lu Z, Guo Y. Role of refractive index in sum frequency generation intensity of salt solution interfaces. CHINESE CHEM LETT 2015. [DOI: 10.1016/j.cclet.2015.10.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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24
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Huang J, Cheng F, Binks BP, Yang H. pH-Responsive Gas-Water-Solid Interface for Multiphase Catalysis. J Am Chem Soc 2015; 137:15015-25. [PMID: 26524337 DOI: 10.1021/jacs.5b09790] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Despite their wide utility in laboratory synthesis and industrial fabrication, gas-water-solid multiphase catalysis reactions often suffer from low reaction efficiency because of the low solubility of gases in water. Using a surface-modification protocol, interface-active silica nanoparticles were synthesized. Such nanoparticles can assemble at the gas-water interface, stabilizing micrometer-sized gas bubbles in water, and disassemble by tuning of the aqueous phase pH. The ability to stabilize gas microbubbles can be finely tuned through variation of the surface-modification protocol. As proof of this concept, Pd and Au were deposited on these silica nanoparticles, leading to interface-active catalysts for aqueous hydrogenation and oxidation, respectively. With such catalysts, conventional gas-water-solid multiphase reactions can be transformed to H2 or O2 microbubble reaction systems. The resultant microbubble reaction systems exhibit significant catalysis efficiency enhancement effects compared with conventional multiphase reactions. The significant improvement is attributed to the pronounced increase in reaction interface area that allows for the direct contact of gas, water, and solid phases. At the end of reaction, the microbubbles can be removed from the reaction systems through changing the pH, allowing product separation and catalyst recycling. Interestingly, the alcohol oxidation activation energy for the microbubble systems is much lower than that for the conventional multiphase reaction, also indicating that the developed microbubble system may be a valuable platform to design innovative multiphase catalysis reactions.
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Affiliation(s)
| | | | - Bernard P Binks
- Surfactant & Colloid Group, Department of Chemistry, University of Hull , Hull HU6 7RX, United Kingdom
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