1
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Wang J, Fan W, Cheng SB, Chen J. Tailoring the Superatomic Characteristics and Optical Behavior of Metal-Free Boron Clusters via Ligand Engineering. J Phys Chem A 2024; 128:7869-7878. [PMID: 39231803 DOI: 10.1021/acs.jpca.4c04808] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/06/2024]
Abstract
It is of great importance to understand how the number and type of ligands influence the properties of clusters through ligand engineering, as this knowledge is crucial for the rational design and optimization of functional materials. Herein, the geometrical structures, binding energies, and electronic properties of nonmetallic Bn (n = 20 and 40) clusters with CO, PEt3, F, NO2, and CN ligands are systematically explored based on density functional theory (DFT) calculations. Our findings demonstrate that the CO ligand acts as an electron donor when attached to these two boron clusters, in contrast to their role as electron acceptors in interactions with metal oxide and metal chalcogenide clusters. This emphasizes the necessity of considering the intrinsic properties of the host cluster when modifying with ligands. Moreover, it was observed that substituting PEt3 with F, NO2, or CN converted the B20 cluster from an electron acceptor to an electron donor, thereby demonstrating the versatility in tuning the redox characteristics of boron clusters by selecting appropriate ligands. Intriguingly, the attachment of the PEt3, F, NO2, and CN ligands to B20 can significantly modulate the electronic properties of B20 to realize the formation of metal-free superalkali (B20(PEt3)n, n = 3-5) and superhalogen (B20F, B20NO2, and B20CN) clusters. Furthermore, the structure, stability, and optical absorption of the charge transfer complex B20(PEt3)3+B20F were analyzed. This complex has been identified as an efficient material for harvesting visible light. Our findings provide insights into the effects of ligand variations on boron cluster functionalities, offering a new perspective for the design of advanced materials with tailored cluster properties through ligand engineering.
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Affiliation(s)
- Jing Wang
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
| | - Weiliu Fan
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
| | - Shi-Bo Cheng
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
| | - Jing Chen
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People's Republic of China
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2
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Gao J, Xie W, Luo X, Qin Y, Zhao Z. Anisotropic Effects in Local Anodic Oxidation Nanolithography on Silicon Surfaces: Insights from ReaxFF Molecular Dynamics. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40. [PMID: 39008811 PMCID: PMC11295202 DOI: 10.1021/acs.langmuir.4c01129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 05/27/2024] [Accepted: 07/02/2024] [Indexed: 07/17/2024]
Abstract
Fully understanding the anisotropic effect of silicon surface orientations in local anodic oxidation (LAO) nanolithography processes is critical to the precise control of oxide quality and rate. This study used ReaxFF MD simulations to reveal the surface anisotropic effects in the LAO through the analysis of adsorbed species, atomic charge, and oxide growth. Our results show that the LAO behaves differently on silicon (100), (110), and (111) surfaces. Specifically, the application of an electric field significantly increases the quantity of surface-adsorbed -OH2 while reducing -OH on the (111) surface, and results in a higher charge on a greater number of Si atoms on the (100) surface. Moreover, the quantity of surface-adsorbed -OH plays a pivotal role in influencing the oxidation rate, as it directly correlates with an increased formation rate of Si-O-Si bonds. During bias-induced oxidation, the (111) surface appears with a high initial oxidation rate among three surfaces, while the (110) surface underwent increased oxidation at higher electric field strengths. This conclusion is based on the analysis of the evolution of Si-O-Si bond number, surface elevation, and oxide thickness. Our findings align well with prior theoretical and experimental studies, providing deeper insights and clear guidance for the fabrication of high-performance nanoinsulator gates using LAO nanolithography.
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Affiliation(s)
- Jian Gao
- Centre for Precision Manufacturing,
Department of Design, Manufacturing and Engineering Management, University of Strathclyde, Glasgow G1 1XJ, U.K.
| | - Wenkun Xie
- Centre for Precision Manufacturing,
Department of Design, Manufacturing and Engineering Management, University of Strathclyde, Glasgow G1 1XJ, U.K.
| | - Xichun Luo
- Centre for Precision Manufacturing,
Department of Design, Manufacturing and Engineering Management, University of Strathclyde, Glasgow G1 1XJ, U.K.
| | - Yi Qin
- Centre for Precision Manufacturing,
Department of Design, Manufacturing and Engineering Management, University of Strathclyde, Glasgow G1 1XJ, U.K.
| | - Zhiyong Zhao
- Centre for Precision Manufacturing,
Department of Design, Manufacturing and Engineering Management, University of Strathclyde, Glasgow G1 1XJ, U.K.
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3
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Listyarini R, Kriesche BM, Hofer TS. Characterization of the Coordination and Solvation Dynamics of Solvated Systems─Implications for the Analysis of Molecular Interactions in Solutions and Pure H 2O. J Chem Theory Comput 2024; 20:3028-3045. [PMID: 38595064 PMCID: PMC11044269 DOI: 10.1021/acs.jctc.4c00162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2024] [Revised: 03/26/2024] [Accepted: 03/28/2024] [Indexed: 04/11/2024]
Abstract
The characterization of solvation shells of atoms, ions, and molecules in solution is essential to relate solvation properties to chemical phenomena such as complex formation and reactivity. Different definitions of the first-shell coordination sphere from simulation data can lead to potentially conflicting data on the structural properties and associated ligand exchange dynamics. The definition of a solvation shell is typically based on a given threshold distance determined from the respective solute-solvent pair distribution function g(r) (i.e., GC). Alternatively, a nearest neighbor (NN) assignment based on geometric properties of the coordination complex without the need for a predetermined cutoff criterion, such as the relative angular distance (RAD) or the modified Voronoi (MV) tessellation, can be applied. In this study, the effect of different NN algorithms on the coordination number and ligand exchange dynamics evaluated for a series of monatomic ions in aqueous solution, carbon dioxide in aqueous and dichloromethane solutions, and pure liquid water has been investigated. In the case of the monatomic ions, the RAD approach is superior in achieving a well separated definition of the first solvation layer. In contrast, the MV algorithm provides a better separation of the NNs from a molecular point of view, leading to better results in the case of solvated CO2. When analyzing the coordination environment in pure water, the cutoff-based GC framework was found to be the most reliable approach. By comparison of the number of ligand exchange reactions and the associated mean ligand residence times (MRTs) with the properties of the coordination number autocorrelation functions, it is shown that although the average coordination numbers are sensitive to the different definitions of the first solvation shell, highly consistent estimates for the associated MRT of the solvated system are obtained in the majority of cases.
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Affiliation(s)
- Risnita
Vicky Listyarini
- Institute
of General, Inorganic and Theoretical Chemistry Center for Chemistry
and Biomedicine, University of Innsbruck Innrain 80-82, A-6020 Innsbruck, Austria
- Chemistry
Education Study Program Sanata Dharma University, Yogyakarta 55282, Indonesia
| | - Bernhard M. Kriesche
- Institute
of General, Inorganic and Theoretical Chemistry Center for Chemistry
and Biomedicine, University of Innsbruck Innrain 80-82, A-6020 Innsbruck, Austria
| | - Thomas S. Hofer
- Institute
of General, Inorganic and Theoretical Chemistry Center for Chemistry
and Biomedicine, University of Innsbruck Innrain 80-82, A-6020 Innsbruck, Austria
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4
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Cheng X, Cheng K, Zhou X, Shi M, Jiang G, Du J. Transition metal single-atoms supported on hexagonal ZnIn 2S 4 monolayers for the hydrogen evolution reaction. Phys Chem Chem Phys 2024; 26:11631-11640. [PMID: 38546425 DOI: 10.1039/d4cp00107a] [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
Herein, we report a series of 5d transition metal (TM) single atoms supported on ZIS as promising catalysts for the hydrogen evolution reaction using first-principles calculations. The binding behaviors of TMs with the ZIS surface in single-atom catalyst formation are analysed using the adsorption energy (Eads), partial density of states (PDOS), charge density difference (CDD), and crystal orbital Hamilton population (COHP). The TM@ZIS (TM = Ta, W, Re, Os, Ir, and Pt) shows excellent hydrogen evolution performance with the Gibbs free energy (ΔGH*) values from -0.120 to 0.128 eV. The Tafel and Heyrovsky reaction mechanisms to drive H2 formation are also identified.
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Affiliation(s)
- Xiujuan Cheng
- College of Physics, Sichuan University, Chengdu 610064, China.
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Kunyang Cheng
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Xuying Zhou
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Mingyang Shi
- College of Physics, Sichuan University, Chengdu 610064, China.
| | - Gang Jiang
- Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China
| | - Jiguang Du
- College of Physics, Sichuan University, Chengdu 610064, China.
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5
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Arandhara M, Ramesh SG. Nuclear Quantum Effects in Hydroxide Hydrate Along the H-Bond Bifurcation Pathway. J Phys Chem A 2024; 128:1600-1610. [PMID: 38393819 DOI: 10.1021/acs.jpca.3c08027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/25/2024]
Abstract
Path integral (PI) simulations are used to explore nuclear quantum effects (NQEs) in hydroxide hydrate and its perdeuterated isotopomer along the H-bond bifurcation pathway. Toward this, a new potential energy surface using the symmetric gradient domain machine learning method with ab initio data at the CCSD(T)/aug-cc-pVTZ level is built. From PI umbrella sampling (US) simulations, free energy profiles along the bifurcation coordinate are explored as a function of temperature. At ambient temperature, the bifurcation barrier is increased upon inclusion of NQEs. At low temperatures in the deep tunneling regime, the barrier is strongly decreased and flattened. These trends are examined, and the role of the O-O distance is also investigated through two-dimensional US simulations.
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Affiliation(s)
- Mrinal Arandhara
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
| | - Sai G Ramesh
- Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India
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6
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Hirata K, Akasaka K, Dopfer O, Ishiuchi SI, Fujii M. Transition from vehicle to Grotthuss proton transfer in a nanosized flask: cryogenic ion spectroscopy of protonated p-aminobenzoic acid solvated with D 2O. Chem Sci 2024; 15:2725-2730. [PMID: 38404372 PMCID: PMC10882521 DOI: 10.1039/d3sc05455a] [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: 10/16/2023] [Accepted: 01/18/2024] [Indexed: 02/27/2024] Open
Abstract
Proton transfer (PT) is one of the most ubiquitous reactions in chemistry and life science. The unique nature of PT has been rationalized not by the transport of a solvated proton (vehicle mechanism) but by the Grotthuss mechanism in which a proton is transported to the nearest proton acceptor along a hydrogen-bonded network. However, clear experimental evidence of the Grotthuss mechanism has not been reported yet. Herein we show by infrared spectroscopy that a vehicle-type PT occurs in the penta- and hexahydrated clusters of protonated p-aminobenzoic acid, while Grotthuss-type PT is observed in heptahydrated clusters, indicating a change in the PT mechanism depending on the degree of hydration. These findings emphasize the importance of the usually ignored vehicle mechanism as well as the degree of hydration. It highlights the possibility of controlling the PT mechanism by the number of water molecules in chemical and biological environments.
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Affiliation(s)
- Keisuke Hirata
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology 4259 Nagatsuta-cho, Midori-ku Yokohama 226-8503 Japan
- Department of Chemistry, School of Science, Tokyo Institute of Technology 2-12-1 Ookayama, Meguro-ku Tokyo 152-8550 Japan
- International Research Frontiers Initiative, Tokyo Institute of Technology 4259 Nagatsuta-cho, Midori-ku Yokohama 226-8503 Japan
| | - Kyota Akasaka
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology 4259 Nagatsuta-cho, Midori-ku Yokohama 226-8503 Japan
- School of Life Science and Technology, Tokyo Institute of Technology 4259 Nagatsuta-cho, Midori-ku Yokohama Kanagawa 226-8503 Japan
| | - Otto Dopfer
- International Research Frontiers Initiative, Tokyo Institute of Technology 4259 Nagatsuta-cho, Midori-ku Yokohama 226-8503 Japan
- Institut für Optik und Atomare Physik, Technische Universität Berlin Hardenbergstrasse 36 10623 Berlin Germany
| | - Shun-Ichi Ishiuchi
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology 4259 Nagatsuta-cho, Midori-ku Yokohama 226-8503 Japan
- Department of Chemistry, School of Science, Tokyo Institute of Technology 2-12-1 Ookayama, Meguro-ku Tokyo 152-8550 Japan
- International Research Frontiers Initiative, Tokyo Institute of Technology 4259 Nagatsuta-cho, Midori-ku Yokohama 226-8503 Japan
| | - Masaaki Fujii
- Laboratory for Chemistry and Life Science, Institute of Innovative Research, Tokyo Institute of Technology 4259 Nagatsuta-cho, Midori-ku Yokohama 226-8503 Japan
- School of Life Science and Technology, Tokyo Institute of Technology 4259 Nagatsuta-cho, Midori-ku Yokohama Kanagawa 226-8503 Japan
- International Research Frontiers Initiative, Tokyo Institute of Technology 4259 Nagatsuta-cho, Midori-ku Yokohama 226-8503 Japan
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7
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Zhou Y, Cao H, An Z, Huo Y, Jiang J, Ma Y, Xie J, He M. Effective boosting of halogenated α, β-unsaturated C 4-dicarbonyl electrocatalytic hydrodehalogenation by 1 T'-MoS 2/Ti 3C 2T 2 (T = O, OH, F) heterojunctions: A theoretical study. JOURNAL OF HAZARDOUS MATERIALS 2024; 461:132531. [PMID: 37716265 DOI: 10.1016/j.jhazmat.2023.132531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Revised: 08/02/2023] [Accepted: 09/09/2023] [Indexed: 09/18/2023]
Abstract
Halogenated α, β-unsaturated C4-dicarbonyl (X-BDA), a novel family of high-toxicity ring cleavage products, is produced during the disinfection of phenolic compounds. The technique of electrocatalytic hydrodehalogenation (ECH) is efficient in rupturing carbon-halogen bonds and generating useful chemicals. This study used first principles to examine the ECH reaction mechanism of X-BDA and the subsequent hydrogenation reaction of the toxic derivative BDA over the 1 T'-MoS2/Ti3C2T2 (T = O, OH, F) catalysts. The catalytic activity of Ti3C2T2 (T = O, OH, F) catalysts decreases gradually with -OH, -F, -O functional group. The loading of 1 T'-MoS2 onto the Ti3C2T2 surface improves the stability and selectivity of Ti3C2T2. In particular, 1 T'-MoS2/Ti3C2(OH)2 is most conducive to the ECH reaction of X-BDA via a direct-indirect continuous reduction process. It exhibits excellent removal capability towards Cl-BDA, with decreasing reactivity in the order of the Cl-, Br-, and I-BDA. The material offers a solution to the challenging dechlorination issue. The dehalogenated product BDA can be hydrogenated to produce 1,4-butanedial, 1,4-butanediol, and 1,4-butenediol. Three valuable chemicals can be obtained by exerting an applied potential of - 0.65 V. This work suggests that the formation of heterojunction catalyst may lead to new strategies to improve ECH for environmental remediation applications.
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Affiliation(s)
- Yuxin Zhou
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
| | - Haijie Cao
- Institute of Materials for Energy and Environment, School of Materials Science and Engineering, Qingdao University, Qingdao 266071, PR China.
| | - Zexiu An
- College of Plant Protection, Hebei Agricultural University, Baoding 071000, PR China
| | - Yanru Huo
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
| | - Jinchan Jiang
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
| | - Yuhui Ma
- Environment Research Institute, Shandong University, Qingdao 266237, PR China
| | - Ju Xie
- School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, PR China
| | - Maoxia He
- Environment Research Institute, Shandong University, Qingdao 266237, PR China.
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8
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Maurer M, Lazaridis T. Comparison of classical and ab initio simulations of hydronium and aqueous proton transfer. J Chem Phys 2023; 159:134506. [PMID: 37795787 DOI: 10.1063/5.0166596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 09/25/2023] [Indexed: 10/06/2023] Open
Abstract
Proton transport in aqueous systems occurs by making and breaking covalent bonds, a process that classical force fields cannot reproduce. Various attempts have been made to remedy this deficiency, by valence bond theory or instantaneous proton transfers, but the ability of such methods to provide a realistic picture of this fundamental process has not been fully evaluated. Here we compare an ab initio molecular dynamics (AIMD) simulation of an excess proton in water to a simulation of a classical H3O+ in TIP3P water. The energy gap upon instantaneous proton transfer from H3O+ to an acceptor water molecule is much higher in the classical simulation than in the AIMD configurations evaluated with the same classical potential. The origins of this discrepancy are identified by comparing the solvent structures around the excess proton in the two systems. One major structural difference is in the tilt angle of the water molecules that accept an hydrogen bond from H3O+. The lack of lone pairs in TIP3P produces a tilt angle that is too large and generates an unfavorable geometry after instantaneous proton transfer. This problem can be alleviated by the use of TIP5P, which gives a tilt angle much closer to the AIMD result. Another important factor that raises the energy gap is the different optimal distance in water-water vs H3O+-water H-bonds. In AIMD the acceptor is gradually polarized and takes a hydronium-like configuration even before proton transfer actually happens. Ways to remedy some of these problems in classical simulations are discussed.
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Affiliation(s)
- Manuela Maurer
- Department of Chemistry, City College of New York/CUNY, 160 Convent Ave., New York, New York 10031, USA
| | - Themis Lazaridis
- Department of Chemistry, City College of New York/CUNY, 160 Convent Ave., New York, New York 10031, USA
- Graduate Programs in Chemistry, Biochemistry, and Physics, The Graduate Center, City University of New York, 365 Fifth Ave., New York, New York 10016, USA
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9
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Nazmutdinov RR, Shermokhamedov SA, Zinkicheva TT, Ulstrup J, Xiao X. Understanding molecular and electrochemical charge transfer: theory and computations. Chem Soc Rev 2023; 52:6230-6253. [PMID: 37551138 DOI: 10.1039/d2cs00006g] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/09/2023]
Abstract
Electron, proton, and proton-coupled electron transfer (PCET) are crucial elementary processes in chemistry, electrochemistry, and biology. We provide here a gentle overview of retrospective and currently developing theoretical formalisms of chemical, electrochemical and biological molecular charge transfer processes, with examples of how to bridge electron, proton, and PCET theory with experimental data. We offer first a theoretical minimum of molecular electron, proton, and PCET processes in homogeneous solution and at electrochemical interfaces. We illustrate next the use of the theory both for simple electron transfer processes, and for processes that involve molecular reorganization beyond the simplest harmonic approximation, with dissociative electron transfer and inclusion of all charge transfer parameters. A core example is the electrochemical reduction of the S2O82- anion. This is followed by discussion of core elements of proton and PCET processes and the electrochemical dihydrogen evolution reaction on different metal, semiconductor, and semimetal (say graphene) electrode surfaces. Other further focus is on stochastic chemical rate theory, and how this concept can rationalize highly non-traditional behaviour of charge transfer processes in mixed solvents. As a second major area we address ("long-range") chemical and electrochemical electron transfer through molecular frameworks using notions of superexchange and hopping. Single-molecule and single-entity electrochemistry are based on electrochemical scanning probe microscopies. (In operando) scanning tunnelling microscopy (STM) and atomic force microscopy (AFM) are particularly emphasized, with theoretical notions and new molecular electrochemical phenomena in the confined tunnelling gap. Single-molecule surface structure and electron transfer dynamics are illustrated by self-assembled thiol molecular monolayers and by more complex redox target molecules. This discussion also extends single-molecule electrochemistry to bioelectrochemistry of complex redox metalloproteins and metalloenzymes. Our third major area involves computational overviews of molecular and electronic structure of the electrochemical interface, with new computational challenges. These relate to solvent dynamics in bulk and confined space (say carbon nanostructures), electrocatalysis, metallic and semiconductor nanoparticles, d-band metals, carbon nanostructures, spin catalysis and "spintronics", and "hot" electrons. Further perspectives relate to metal-organic frameworks, chiral surfaces, and spintronics.
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Affiliation(s)
- Renat R Nazmutdinov
- Department of Inorganic Chemistry, Kazan National Research Technological University, K. Marx Str., 68, 420015 Kazan, Republic of Tatarstan, Russian Federation.
| | - Shokirbek A Shermokhamedov
- Department of Inorganic Chemistry, Kazan National Research Technological University, K. Marx Str., 68, 420015 Kazan, Republic of Tatarstan, Russian Federation.
| | - Tamara T Zinkicheva
- Department of Inorganic Chemistry, Kazan National Research Technological University, K. Marx Str., 68, 420015 Kazan, Republic of Tatarstan, Russian Federation.
| | - Jens Ulstrup
- Department of Inorganic Chemistry, Kazan National Research Technological University, K. Marx Str., 68, 420015 Kazan, Republic of Tatarstan, Russian Federation.
- Department of Chemistry, Technical University of Denmark, Building 207, Kemitorvet, 2800 Kongens Lyngby, Denmark.
| | - Xinxin Xiao
- Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
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10
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Atsango AO, Morawietz T, Marsalek O, Markland TE. Developing machine-learned potentials to simultaneously capture the dynamics of excess protons and hydroxide ions in classical and path integral simulations. J Chem Phys 2023; 159:074101. [PMID: 37581418 DOI: 10.1063/5.0162066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 07/31/2023] [Indexed: 08/16/2023] Open
Abstract
The transport of excess protons and hydroxide ions in water underlies numerous important chemical and biological processes. Accurately simulating the associated transport mechanisms ideally requires utilizing ab initio molecular dynamics simulations to model the bond breaking and formation involved in proton transfer and path-integral simulations to model the nuclear quantum effects relevant to light hydrogen atoms. These requirements result in a prohibitive computational cost, especially at the time and length scales needed to converge proton transport properties. Here, we present machine-learned potentials (MLPs) that can model both excess protons and hydroxide ions at the generalized gradient approximation and hybrid density functional theory levels of accuracy and use them to perform multiple nanoseconds of both classical and path-integral proton defect simulations at a fraction of the cost of the corresponding ab initio simulations. We show that the MLPs are able to reproduce ab initio trends and converge properties such as the diffusion coefficients of both excess protons and hydroxide ions. We use our multi-nanosecond simulations, which allow us to monitor large numbers of proton transfer events, to analyze the role of hypercoordination in the transport mechanism of the hydroxide ion and provide further evidence for the asymmetry in diffusion between excess protons and hydroxide ions.
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Affiliation(s)
- Austin O Atsango
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | - Tobias Morawietz
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
| | - Ondrej Marsalek
- Faculty of Mathematics and Physics, Charles University, Prague, Czech Republic
| | - Thomas E Markland
- Department of Chemistry, Stanford University, Stanford, California 94305, USA
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11
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Huo J, Chen J, Liu P, Hong B, Zhang J, Dong H, Li S. Microscopic Mechanism of Proton Transfer in Pure Water under Ambient Conditions. J Chem Theory Comput 2023. [PMID: 37365994 DOI: 10.1021/acs.jctc.3c00244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
Water molecules and the associated proton transfer (PT) are prevalent in chemical and biological systems and have been a hot research topic. Spectroscopic characterization and ab initio molecular dynamics (AIMD) simulations have previously revealed insights into acidic and basic liquids. Presumably, the situation in the acidic/basic solution is not necessarily the same as in pure water; in addition, the autoionization constant for water is only 10-14 under ambient conditions, making the study of PT in pure water challenging. To overcome this issue, we modeled periodic water box systems containing 1000 molecules for tens of nanoseconds based on a neural network potential (NNP) with quantum mechanical accuracy. The NNP was generated by training a dataset containing the energies and atomic forces of 17 075 configurations of periodic water box systems, and these data points were calculated at the MP2 level that considers electron correlation effects. We found that the size of the system and the duration of the simulation have a significant impact on the convergence of the results. With these factors considered, our simulations showed that hydronium (H3O+) and hydroxide (OH-) ions in water have distinct hydration structures, thermodynamic and kinetic properties, e.g., the longer-lasting and more stable hydrated structure of OH- ions than that of H3O+, as well as a significantly higher free energy barrier for the OH--associated PT than that of H3O+, leading the two to exhibit completely different PT behaviors. Given these characteristics, we further found that PT via OH- ions tends not to occur multiple times or between many molecules. In contrast, PT via H3O+ can synergistically occur among multiple molecules and prefers to adopt a cyclic pattern among three water molecules, while it occurs mostly in a chain pattern when more water molecules are involved. Therefore, our studies provide a detailed and solid microscopic explanation for the PT process in pure water.
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Affiliation(s)
- Jun Huo
- Kuang Yaming Honors School, Nanjing University, Nanjing 210023, China
| | - Jianghao Chen
- Kuang Yaming Honors School, Nanjing University, Nanjing 210023, China
- School of Physics, National Laboratory of Solid State Microstructure, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Pei Liu
- School of Chemistry and Chemical Engineering, Key Laboratory of Mesoscopic Chemistry of Ministry of Education, Institute of Theoretical and Computational Chemistry, Nanjing University, Nanjing 210023, China
| | - Benkun Hong
- School of Chemistry and Chemical Engineering, Key Laboratory of Mesoscopic Chemistry of Ministry of Education, Institute of Theoretical and Computational Chemistry, Nanjing University, Nanjing 210023, China
| | - Jian Zhang
- School of Physics, National Laboratory of Solid State Microstructure, and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
| | - Hao Dong
- Kuang Yaming Honors School, Nanjing University, Nanjing 210023, China
- State Key Laboratory of Analytical Chemistry for Life Science, Nanjing University, Nanjing 210023, China
- Institute for Brain Sciences, Nanjing University, Nanjing 210023, China
| | - Shuhua Li
- School of Chemistry and Chemical Engineering, Key Laboratory of Mesoscopic Chemistry of Ministry of Education, Institute of Theoretical and Computational Chemistry, Nanjing University, Nanjing 210023, China
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12
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Codescu MA, Kunze T, Weiß M, Brehm M, Kornilov O, Sebastiani D, Nibbering ETJ. Ultrafast Proton Transfer Pathways Mediated by Amphoteric Imidazole. J Phys Chem Lett 2023; 14:4775-4785. [PMID: 37186569 DOI: 10.1021/acs.jpclett.3c00595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/17/2023]
Abstract
Imidazole, being an amphoteric molecule, can act both as an acid and as a base. This property enables imidazole, as an essential building block, to effectively facilitate proton transport in high-temperature proton exchange membrane fuel cells and in proton channel transmembrane proteins, enabling those systems to exhibit high energy conversion yields and optimal biological function. We explore the amphoteric properties of imidazole by following the proton transfer exchange reaction dynamics with the bifunctional photoacid 7-hydroxyquinoline (7HQ). We show with ultrafast ultraviolet-mid-infrared pump-probe spectroscopy how for imidazole, in contrast to expectations based on textbook knowledge of acid-base reactivity, the preferential reaction pathway is that of an initial proton transfer from 7HQ to imidazole, and only at a later stage a transfer from imidazole to 7HQ, completing the 7HQ tautomerization reaction. An assessment of the molecular distribution functions and first-principles calculations of proton transfer reaction barriers reveal the underlying reasons for our observations.
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Affiliation(s)
- Marius-Andrei Codescu
- Max Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max Born Strasse 2A, 12489 Berlin, Germany
| | - Thomas Kunze
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany
| | - Moritz Weiß
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany
| | - Martin Brehm
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany
| | - Oleg Kornilov
- Max Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max Born Strasse 2A, 12489 Berlin, Germany
| | - Daniel Sebastiani
- Institut für Chemie, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz 4, 06120 Halle (Saale), Germany
| | - Erik T J Nibbering
- Max Born Institut für Nichtlineare Optik und Kurzzeitspektroskopie, Max Born Strasse 2A, 12489 Berlin, Germany
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13
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Kramer A, Pachter R, Hsu JWP, Vandenberghe WG. The effect of solvent on determining highest occupied molecular orbital energies of semiconducting organic molecules: Insight from a combined computational approach. J Comput Chem 2023; 44:1064-1072. [PMID: 36597937 DOI: 10.1002/jcc.27065] [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: 09/15/2022] [Revised: 11/27/2022] [Accepted: 12/18/2022] [Indexed: 01/05/2023]
Abstract
Although cyclic voltammetry (CV) measurements in solution have been widely used to determine the highest occupied molecular orbital energy (EHOMO ) of semiconducting organic molecules, an understanding of the experimentally observed discrepancies due to the solvent used is lacking. To explain these differences, we investigate the solvent effects on EHOMO by combining density functional theory and molecular dynamics calculations for four donor molecules with a common backbone moiety. We compare the experimental EHOMO values to the calculated values obtained from either implicit or first solvation shell theories. We find that the first solvation shell method can capture the EHOMO variation arising from the functional groups in solution, unlike the implicit method. We further applied the first solvation shell method to other semiconducting organic molecules measured in solutions for different solvents. We find that the EHOMO obtained using an implicit method is insensitive to solvent choice. The first solvation shell, however, produces EHOMO values that are sensitive to solvent choices and agrees with published experimental results. The solvent sensitivity arises from a hierarchy of three effects: (1) the solute electronic state within a surrounding dielectric continuum, (2) ambient temperature or solvent atoms changing the solute geometry, and (3) electronic interactions between the solute and solvents. The implicit method, on the other hand, only captures the effect of a dielectric environment. Our findings suggest that EHOMO obtained by CV measurements should account for the influence of solvent when the results are reported, interpreted, or compared to other molecules.
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Affiliation(s)
- Aaron Kramer
- Department of Physics, University of Texas at Dallas, Richardson, Texas, USA
| | - Ruth Pachter
- Air Force Research Laboratory, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, Ohio, USA
| | - Julia W P Hsu
- Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas, USA
| | - William G Vandenberghe
- Department of Materials Science and Engineering, University of Texas at Dallas, Richardson, Texas, USA
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14
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In situ electrochemical Raman spectroscopy and ab initio molecular dynamics study of interfacial water on a single-crystal surface. Nat Protoc 2023; 18:883-901. [PMID: 36599962 DOI: 10.1038/s41596-022-00782-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2022] [Accepted: 09/12/2022] [Indexed: 01/05/2023]
Abstract
The dynamics and chemistry of interfacial water are essential components of electrocatalysis because the decomposition and formation of water molecules could dictate the protonation and deprotonation processes on the catalyst surface. However, it is notoriously difficult to probe interfacial water owing to its location between two condensed phases, as well as the presence of external bias potentials and electrochemically induced reaction intermediates. An atomically flat single-crystal surface could offer an attractive platform to resolve the internal structure of interfacial water if advanced characterization tools are developed. To this end, here we report a protocol based on the combination of in situ Raman spectroscopy and ab initio molecular dynamics (AIMD) simulations to unravel the directional molecular features of interfacial water. We present the procedures to prepare single-crystal electrodes, construct a Raman enhancement mode with shell-isolated nanoparticle, remove impurities, eliminate the perturbation from bulk water and dislodge the hydrogen bubbles during in situ electrochemical Raman experiments. The combination of the spectroscopic measurements with AIMD simulation results provides a roadmap to decipher the potential-dependent molecular orientation of water at the interface. We have prepared a detailed guideline for the application of combined in situ Raman and AIMD techniques; this procedure may take a few minutes to several days to generate results and is applicable to a variety of disciplines ranging from surface science to energy storage to biology.
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15
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Yan S, Wang B, Lin H. Tracking the Delocalized Proton in Concerted Proton Transfer in Bulk Water. J Chem Theory Comput 2023; 19:448-459. [PMID: 36630655 DOI: 10.1021/acs.jctc.2c01097] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A solvated proton in water is often characterized as a charge or structural defect, and it is important to track its evolution on-the-fly in certain dynamics simulations. Previously, we introduced the proton indicator, a pseudo-atom, whose position approximates the location of the excess proton modeled as a structural defect. The proton indicator generally yields a smooth trajectory of a hydrated proton diffusing in aqueous solutions, including in the events of stepwise proton transfer via the Grotthuss mechanism; however, the proton indicator did not perform well in the events of concerted proton transfer, for which it occasionally yielded large position displacements between two successive time steps. To overcome this hurdle, we develop a new algorithm of a proton indicator with greatly enhanced performance for concerted proton transfer in bulk water. A protocol is proposed to exhaustively explore the hydrogen-bonding network of the water wires over which the excess proton is delocalized and to properly account for the contributions of the water molecules in this network as the geometry evolves. The new proton indicator (called Indicator 2.0) is assessed in dynamics simulations of an excess proton in bulk water and in specially constructed model systems of more complex architectures. The results demonstrate that the new indicator yields a smooth trajectory in both stepwise and concerted proton transfers.
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Affiliation(s)
- Shengheng Yan
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen360015P. R. China
| | - Binju Wang
- State Key Laboratory of Physical Chemistry of Solid Surfaces and Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen360015P. R. China
| | - Hai Lin
- Department of Chemistry, CB 194, University of Colorado Denver, P.O. Box 173364, Denver, Colorado80217, United States
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16
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Degradation by hydrolysis of three triphenylmethane dyes: DFT and TD-DFT study. Theor Chem Acc 2023. [DOI: 10.1007/s00214-022-02950-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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17
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Li M, Li L, Huang X, Qi X, Deng M, Jiang S, Wei Z. Platinum-Water Interaction Induced Interfacial Water Orientation That Governs the pH-Dependent Hydrogen Oxidation Reaction. J Phys Chem Lett 2022; 13:10550-10557. [PMID: 36342770 DOI: 10.1021/acs.jpclett.2c02907] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Understanding the electrode-water interface structure in acid and alkali is crucial to unveiling the underlying mechanism of pH-dependent hydrogen oxidation reaction (HOR) kinetics. In this work, we construct the explicit Pt(111)-H2O interface models in both acid and alkali to investigate the relationship between the HOR mechanism and electrode-electrolyte interface structure using ab initio molecular dynamics and density functional theory. We find that the interfacial water orientation in the outer Helmholtz layer (OHP) induced by the Pt-water interaction governs the pH-dependent HOR kinetics on Pt(111). In alkali, the strong Pt-interfacial water electrostatic interaction behaves as a narrow OHP, which increases the proportion of "H-down" interfacial water and leads to less adsorbed water entering the inner Helmholtz plane (IHP), decreasing the work function of Pt(111). Furthermore, the more "H-down" interfacial water stabilizes the Had adsorption, prevents Had desorption, and suppresses the Volmer step of HOR by forming the solvated [Had···H2O···H2O] complex. Our work provided a visualized molecular-level mechanism to understand the nature of pH-dependent HOR kinetics.
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Affiliation(s)
- Mengting Li
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, Chongqing Key Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Chongqing400044, China
| | - Li Li
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, Chongqing Key Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Chongqing400044, China
| | - Xun Huang
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, Chongqing Key Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Chongqing400044, China
| | - Xueqiang Qi
- College of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing400054, China
| | - Mingming Deng
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, Chongqing Key Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Chongqing400044, China
| | - Shangkun Jiang
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, Chongqing Key Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Chongqing400044, China
| | - Zidong Wei
- The State Key Laboratory of Power Transmission Equipment & System Security and New Technology, Chongqing Key Laboratory of Chemical Process for Clean Energy and Resource Utilization, Chongqing Key Laboratory of Theoretical and Computational Chemistry, School of Chemistry and Chemical Engineering, Chongqing University, Chongqing400044, China
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18
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Computational Insight into Defective Boron Nitride Supported Double-Atom Catalysts for Electrochemical Nitrogen Reduction. Catalysts 2022. [DOI: 10.3390/catal12111404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Designing highly selective and efficient double-atom electrocatalysts (DACs) is essential for achieving a superior nitrogen-reduction reaction (NRR) performance. Herein, we explored the defective boron nitride–supported cage-like double-atom catalysts to rummage the qualified NRR catalysts. Based on a systematic evaluation of the stability, N2 adsorption, NRR selectivity and activity of 10 DACs of TM1-TM2@VB-BN, we predicted Ru-Ti@VB-BN to be the NRR candidate with a limiting potential of −0.40 V. Compared to the corresponding single-atom catalysts, the introduction of Ti/Mo modulates the d-band center of the active metal atom, which improves the NRR performance. Moreover, the magnetic Ru-Ti dimer can facilitate the transfer of charge to molecular N2, ensuring a significant activation of the inert N≡N bond. This research not only opens up new avenues for designing boron nitride–supported DACs for NRR, but also deepens the understanding of DACs in N2 activation.
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19
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Brünig FN, Hillmann P, Kim WK, Daldrop JO, Netz RR. Proton-transfer spectroscopy beyond the normal-mode scenario. J Chem Phys 2022; 157:174116. [DOI: 10.1063/5.0116686] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
A stochastic theory is developed to predict the spectral signature of proton-transfer processes and is applied to infrared spectra computed from ab initio molecular-dynamics simulations of a single [Formula: see text] cation. By constraining the oxygen atoms to a fixed distance, this system serves as a tunable model for general proton-transfer processes with variable barrier height. Three spectral contributions at distinct frequencies are identified and analytically predicted: the quasi-harmonic motion around the most probable configuration, amenable to normal-mode analysis, the contribution due to transfer paths when the proton moves over the barrier, and a shoulder for low frequencies stemming from the stochastic transfer-waiting-time distribution; the latter two contributions are not captured by normal-mode analysis but exclusively reported on the proton-transfer kinetics. In accordance with reaction rate theory, the transfer-waiting-contribution frequency depends inversely exponentially on the barrier height, whereas the transfer-path-contribution frequency is rather insensitive to the barrier height.
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Affiliation(s)
- Florian N. Brünig
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
| | - Paul Hillmann
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
| | - Won Kyu Kim
- School of Computational Sciences, Korea Institute for Advanced Study, Seoul 02455, Republic of Korea
| | - Jan O. Daldrop
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
| | - Roland R. Netz
- Department of Physics, Freie Universität Berlin, 14195 Berlin, Germany
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20
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Windom ZW, Datta M, Huda MM, Sabuj MA, Rai N. Understanding speciation and solvation of glyphosate from first principles simulations. J Mol Liq 2022. [DOI: 10.1016/j.molliq.2022.120154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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21
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Tran B, Cai Y, Janik MJ, Milner ST. Hydrogen Bond Thermodynamics in Aqueous Acid Solutions: A Combined DFT and Classical Force-Field Approach. J Phys Chem A 2022; 126:7382-7398. [PMID: 36190836 DOI: 10.1021/acs.jpca.2c04124] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The thermodynamics of hydrogen bonds in aqueous and acidic solutions significantly impacts the kinetics and thermodynamics of acid reaction chemistry. We utilize in this work a multiscale approach, combining density functional theory (DFT) with classical molecular dynamics (MD) to model hydrogen bond thermodynamics in an acidic solution. Using thermodynamic cycles, we split the solution phase free energy into its gas phase counterpart plus solvation free energies. We validate this DFT/MD approach by calculating the aqueous phase hydrogen bond free energy between two water molecules (H2O-···-H2O), the free energy to transform an H3O+ cation into an H5O2+ cation, and the hydrogen bond free energy of protonated water clusters (H3O+-···-H2O and H5O2+-···-H2O). The computed equilibrium hydrogen bond free energy of H2O-···-H2O is remarkably accurate, especially considering the large individual contributions to the thermodynamic cycle. Turning to cations, we find the ion to be more stable than H3O+ by roughly 1-2 kBT. This small free energy difference allows for thermal fluctuation between the two idealized motifs, consistent with spectroscopic and simulation studies. Lastly, hydrogen bonding free energies between either H+ cation and H2O in solution were found to be stronger than between two H2O, though much less so than in vacuum because of dielectric screening in solution. Altogether, our results suggest the DFT/MD approach is promising for application in modeling hydrogen bonding and proton transfer thermodynamics in condensed phases.
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Affiliation(s)
- Bolton Tran
- Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania16801, United States
| | - Yusheng Cai
- Department of Chemical & Biomolecular Engineering, University of Pennsylvania, Philadelphia, Pennsylvania19104, United States
| | - Michael J Janik
- Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania16801, United States
| | - Scott T Milner
- Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania16801, United States
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22
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Brünig FN, Rammler M, Adams EM, Havenith M, Netz RR. Spectral signatures of excess-proton waiting and transfer-path dynamics in aqueous hydrochloric acid solutions. Nat Commun 2022; 13:4210. [PMID: 35864099 PMCID: PMC9304333 DOI: 10.1038/s41467-022-31700-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Accepted: 06/22/2022] [Indexed: 11/23/2022] Open
Abstract
The theoretical basis for linking spectral signatures of hydrated excess protons with microscopic proton-transfer mechanisms has so far relied on normal-mode analysis. We introduce trajectory-decomposition techniques to analyze the excess-proton dynamics in ab initio molecular-dynamics simulations of aqueous hydrochloric-acid solutions beyond the normal-mode scenario. We show that the actual proton transfer between two water molecules involves for relatively large water-water separations crossing of a free-energy barrier and thus is not a normal mode, rather it is characterized by two non-vibrational time scales: Firstly, the broadly distributed waiting time for transfer to occur with a mean value of 200-300 fs, which leads to a broad and weak shoulder in the absorption spectrum around 100 cm-1, consistent with our experimental THz spectra. Secondly, the mean duration of a transfer event of about 14 fs, which produces a rather well-defined spectral contribution around 1200 cm-1 and agrees in location and width with previous experimental mid-infrared spectra.
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Affiliation(s)
- Florian N Brünig
- Freie Universität Berlin, Department of Physics, 14195, Berlin, Germany
| | - Manuel Rammler
- Freie Universität Berlin, Department of Physics, 14195, Berlin, Germany
| | - Ellen M Adams
- Ruhr-Universität Bochum, Department of Physical Chemistry II, 44780, Bochum, Germany
| | - Martina Havenith
- Ruhr-Universität Bochum, Department of Physical Chemistry II, 44780, Bochum, Germany
| | - Roland R Netz
- Freie Universität Berlin, Department of Physics, 14195, Berlin, Germany.
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23
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Zhang GG, Duan XY, Zhao Y, Wei M. Three Proton‐conductors Based‐on Keggin‐type Polyoxometalates Well‐arranged in the Networks of Dinuclear‐Cu(II)‐mixed‐organic‐ligand Clusters. Eur J Inorg Chem 2022. [DOI: 10.1002/ejic.202200382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Guang-Guang Zhang
- Henan Normal University School of Chemistry and Chemical Engineering CHINA
| | | | - Yan Zhao
- Henan Normal University School of Chemistry and Chemical Engineering CHINA
| | - Meilin Wei
- - - 46# East of Construction Road 453007 Xinxiang CHINA
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24
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Fukushima T, Yoshimitsu S, Murakoshi K. Inherent Promotion of Ionic Conductivity via Collective Vibrational Strong Coupling of Water with the Vacuum Electromagnetic Field. J Am Chem Soc 2022; 144:12177-12183. [PMID: 35737737 DOI: 10.1021/jacs.2c02991] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Hydrogen bonding interactions among water molecules play a critical role in chemical reactivity, dynamic proton mobility, static dielectric behavior, and the thermodynamic properties of water. In this study, we demonstrate the modification of ionic conductivity of water through hybridization with a vacuum electromagnetic field by strongly coupling the O─H stretching mode of H2O to a Fabry-Perot cavity mode. The hybridization generates collective vibro-polaritonic states, thereby enhancing the proton conductivity by an order of magnitude at resonance. In addition, the dielectric constants increase at resonance in the coupled state. The findings presented herein reveal how a vacuum electromagnetic environment can be engineered to control the ground-state properties of water.
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Affiliation(s)
- Tomohiro Fukushima
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Soushi Yoshimitsu
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Kei Murakoshi
- Department of Chemistry, Faculty of Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
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25
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Joutsuka T. Molecular Mechanism of Autodissociation in Liquid Water: Ab Initio Molecular Dynamics Simulations. J Phys Chem B 2022; 126:4565-4571. [PMID: 35694850 DOI: 10.1021/acs.jpcb.2c01971] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Autodissociation in liquid water is one of the most important processes in various topics of physical chemistry, such as acid-base chemistry. Molecular simulations have elucidated most of the molecular mechanisms at the atomic level, yet quantitative analysis to compare with experiments using the potential of mean force (PMF) remains a hurdle, including the definition of reaction coordinates and the accuracy of liquid structures by ab initio molecular dynamics (AIMD) simulations with density functional theory (DFT) methods. Here, we perform AIMD simulations with the revPBE-D3 exchange-correlation functional to compute the PMF profiles of autoionization, or proton transfer (PT), in liquid water. For the quantitative analysis with physically meaningful reaction coordinates, we employ a PT coordinate, donor-acceptor (OH--H3O+) distance, and hydrogen (H)-bond number. The one-dimensional (1D) PMF profile along the PT coordinate shows no local minimum in the product state of PT (OH- and H3O+), which is necessary to accurately compute the acid dissociation constant (or pKa). On the other hand, the 2D PMF profiles along the PT coordinate and donor-acceptor distance show local minima in the product state and reaction barriers, and the computed pKw is comparable to the experiment. In addition, the 2D PMF profiles along the PT coordinate and the H-bond number reveal the molecular mechanism of the H-bond rearrangement concomitant with PT, in which the H-bond breaking before PT is slightly preferable. These findings indicate that an accurate evaluation of pKa by MD simulations requires the donor-acceptor distance in addition to the conventional PT coordinate.
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Affiliation(s)
- Tatsuya Joutsuka
- Institute of Quantum Beam Science, Graduate School of Science and Engineering, Ibaraki University, Hitachi 316-8511 Ibaraki, Japan.,Frontier Research Center for Applied Atomic Sciences, Ibaraki University, 162-1 Shirakata, Tokai, 319-1106 Ibaraki, Japan
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26
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Liu R, Zhang C, Liang X, Liu J, Wu X, Chen M. Structural and Dynamic Properties of Solvated Hydroxide and Hydronium Ions in Water from Ab Initio Modeling. J Chem Phys 2022; 157:024503. [DOI: 10.1063/5.0094944] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Predicting the asymmetric structure and dynamics of solvated hydroxide and hydronium in water has been a challenging task from ab initio molecular dynamics (AIMD). The difficulty mainly comes from a lack of accurate and efficient exchange-correlation functional in elucidating the amphiphilic nature and the ubiquitous proton transfer behaviors of the two ions. By adopting the strongly-constrained and appropriately normed (SCAN) meta-GGA functional in AIMD simulations, we systematically examine the amphiphilic properties, the solvation structures, the electronic structures, and the dynamic properties of the two water ions. In particular, we compare these results to those predicted by the PBE0-TS functional, which is an accurate yet computationally more expensive exchange-correlation functional. We demonstrate that the general-purpose SCAN functional provides a reliable choice in describing the two water ions. Specifically, in the SCAN picture of water ions, the appearance of the fourth and fifth hydrogen bonds near hydroxide stabilizes the pot-like shape solvation structure and suppresses the structural diffusion, while the hydronium stably donates three hydrogen bonds to its neighbors. We apply a detailed analysis of the proton transfer mechanism of the two ions and find the two ions exhibit substantially different proton transfer patterns. Our AIMD simulations indicate hydroxide diffuses slower than hydronium in water, which is consistent with the experiments.
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Affiliation(s)
| | | | | | | | - Xifan Wu
- Physics, Temple University, United States of America
| | - Mohan Chen
- College of Engineering, Peking University, China
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27
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Konermann L, Kim S. Grotthuss Molecular Dynamics Simulations for Modeling Proton Hopping in Electrosprayed Water Droplets. J Chem Theory Comput 2022; 18:3781-3794. [PMID: 35544700 DOI: 10.1021/acs.jctc.2c00001] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Excess protons in water exhibit unique transport properties because they can rapidly hop along H-bonded water wires. Considerable progress has been made in unraveling this Grotthuss diffusion mechanism using quantum mechanical-based computational techniques. Unfortunately, high computational cost tends to restrict those techniques to small systems and short times. Molecular dynamics (MD) simulations can be applied to much larger systems and longer time windows. However, standard MD methods do not permit the dissociation/formation of covalent bonds, such that Grotthuss diffusion cannot be captured. Here, we bridge this gap by combining atomistic MD simulations (using Gromacs and TIP4P/2005 water) with proton hopping. Excess protons are modeled as hydronium ions that undergo H3O+ + H2O → H2O + H3O+ transitions. In accordance with ab initio MD data, these Grotthuss hopping events are executed in "bursts" with quasi-instantaneous hopping across one or more waters. The bursts are separated by regular MD periods during which H3O+ ions undergo Brownian diffusion. The resulting proton diffusion coefficient agrees with the literature value. We apply this Grotthuss MD technique to highly charged water droplets that are in a size regime encountered during electrospray ionization (5 nm radius, ∼17,000 H2O). The droplets undergo rapid solvent evaporation and occasional H3O+ ejection, keeping them at ca. 81% of the Rayleigh limit. The simulated behavior is consistent with phase Doppler anemometry data. The Grotthuss MD technique developed here should be useful for modeling the behavior of various proton-containing systems that are too large for high-level computational approaches. In particular, we envision future applications related to electrospray processes, where earlier simulations used metal cations while in reality excess protons dominate.
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Affiliation(s)
- Lars Konermann
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
| | - Scott Kim
- Department of Chemistry, The University of Western Ontario, London, Ontario N6A 5B7, Canada
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28
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Mabuchi T. Revealing the Anticorrelation Behavior Mechanism between the Grotthuss and Vehicular Diffusions for Proton Transport in Concentrated Acid Solutions. J Phys Chem B 2022; 126:3319-3326. [PMID: 35468285 DOI: 10.1021/acs.jpcb.1c09742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In this study, we performed reactive molecular dynamics simulations to characterize proton solvation and transport in concentrated hydrochloric acid solutions. The correlation contribution to the total proton mean square displacement is found to be negative for all acid concentrations, indicating the anticorrelation between the Grotthuss and vehicular diffusions. For the vehicular diffusion, the hydronium ions tend to move freely toward the lone pair side independent of acid concentrations, whereas for the Grotthuss diffusion, the proton hopping direction is limited to one of the hydrogen-bonded water molecules on the opposite side of the lone pair region, which are specifically oriented with respect to the neighboring hydronium ion at higher acid concentrations. This result is justified by our findings of the higher fraction of proton rattling with the single hopping event and longer hydrogen bond lifetimes at higher acid concentrations. However, the angular distribution for both the vehicular and Grotthuss diffusions is found to be rather broad and comparable for all acid concentrations, and thus, the anticorrelation shows a minimal dependence on the acid concentration. Our results reveal that the anticorrelation behavior between the vehicle and Grotthuss diffusions is attributed to the amphiphilic nature of hydronium ions and thus is independent of the acid concentrations in solutions.
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Affiliation(s)
- Takuya Mabuchi
- Frontier Research Institute for Interdisciplinary Sciences, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan.,Institute of Fluid Science, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, Miyagi 980-8577, Japan
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29
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Wang J, Zheng M, Zhao X, Fan W. Structure-Performance Descriptors and the Role of the Axial Oxygen Atom on M–N 4–C Single-Atom Catalysts for Electrochemical CO 2 Reduction. ACS Catal 2022. [DOI: 10.1021/acscatal.2c00429] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Jing Wang
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People’s Republic of China
| | - Mingyue Zheng
- State Key Laboratory of Crystal Materials, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People’s Republic of China
| | - Xian Zhao
- Center for Optics Research and Engineering of Shandong University, Shandong University, Oingdao 266237, People’s Republic of China
| | - Weiliu Fan
- School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, People’s Republic of China
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30
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Villafuerte J, Sarigiannidou E, Donatini F, Kioseoglou J, Chaix-Pluchery O, Pernot J, Consonni V. Modulating the growth of chemically deposited ZnO nanowires and the formation of nitrogen- and hydrogen-related defects using pH adjustment. NANOSCALE ADVANCES 2022; 4:1793-1807. [PMID: 36132162 PMCID: PMC9417859 DOI: 10.1039/d1na00785h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 02/22/2022] [Indexed: 06/15/2023]
Abstract
ZnO nanowires (NWs) grown by chemical bath deposition (CBD) have received great interest for nanoscale engineering devices, but their formation in aqueous solution containing many impurities needs to be carefully addressed. In particular, the pH of the CBD solution and its effect on the formation mechanisms of ZnO NWs and of nitrogen- and hydrogen-related defects in their center are still unexplored. By adjusting its value in a low- and high-pH region, we show the latent evolution of the morphological and optical properties of ZnO NWs, as well as the modulated incorporation of nitrogen- and hydrogen-related defects in their center using Raman and cathodoluminescence spectroscopy. The increase in pH is related to the increase in the oxygen chemical potential (μ O), for which the formation energy of hydrogen in bond-centered sites (HBC) and VZn-NO-H defect complexes is found to be unchanged, whereas the formation energy of zinc vacancy (VZn) and zinc vacancy-hydrogen (VZn-nH) complexes steadily decreases as shown from density-functional theory calculations. Revealing that these VZn-related defects are energetically favorable to form as μ O is increased, ZnO NWs grown in the high-pH region are found to exhibit a higher density of VZn-nH defect complexes than ZnO NWs grown in the low-pH region. Annealing at 450 °C under an oxygen atmosphere helps tuning the optical properties of ZnO NWs by reducing the density of HBC and VZn-related defects, while activating the formation of VZn-NO-H defect complexes. These findings show the influence of pH on the nature of Zn(ii) species, the electrostatic interactions between these species and ZnO NW surfaces, and the formation energy of the involved defects. They emphasize the crucial role of the pH of the CBD solution and open new possibilities for simultaneously engineering the morphology of ZnO NWs and the formation of nitrogen- and hydrogen-related defects.
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Affiliation(s)
- José Villafuerte
- Université Grenoble Alpes, CNRS, Grenoble INP, LMGP F-38000 Grenoble France
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut NEEL F-38000 Grenoble France
| | | | - Fabrice Donatini
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut NEEL F-38000 Grenoble France
| | - Joseph Kioseoglou
- Physics Department, Aristotle University of Thessaloniki 54124 Thessaloniki Greece
| | | | - Julien Pernot
- Université Grenoble Alpes, CNRS, Grenoble INP, Institut NEEL F-38000 Grenoble France
| | - Vincent Consonni
- Université Grenoble Alpes, CNRS, Grenoble INP, LMGP F-38000 Grenoble France
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31
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Zelovich T, Tuckerman ME. Controlling Hydronium Diffusivity in Model Proton Exchange Membranes. J Phys Chem Lett 2022; 13:2245-2253. [PMID: 35238561 DOI: 10.1021/acs.jpclett.1c04071] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Fuel-cell-based proton exchange membranes (PEMs) show great potential as cost-effective and clean energy conversion devices. In our recent work, we found that for the low-hydrated model PEMs with a inhomogeneous water distribution and a sulfonate anionic functional end group (SO3-), the H3O+ reacts with SO3- according to SO3- + H3O+ ↔ SO3H + H2O, indicating that the anions in PEMs become active participants in the hydronium diffusion. In this work, we use fully atomistic ab initio molecular dynamics simulations to elucidate the optimal conditions that would promote the participation of SO3- in the hydronium diffusion mechanism by increasing the H3O+/SO3- reactivity, thus increasing the hydronium diffusivity along the cell. The results presented in this work allow us to suggest a set of design rules for creating novel, highly conductive PEMs operating at high temperatures under a nonuniform water distribution using a linker/anion with a relatively high pKa such as (CH2)2SO3. We expect that the discovery of these key design principles will play an important role in the synthesis of high-performing materials for emerging PEM-based fuel cell technologies.
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Affiliation(s)
- Tamar Zelovich
- Department of Chemistry, New York University, New York, New York 10003, United States
| | - Mark E Tuckerman
- Department of Chemistry, New York University, New York, New York 10003, United States
- Courant Institute of Mathematical Sciences, New York University, New York, New York 10012, United States
- NYU-ECNU Center for Computational Chemistry, New York University Shanghai, 3663 North Zhongshan Rd, Shanghai 200062, China
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32
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Kirchner B, Ingenmey J, von Domaros M, Perlt E. The Ionic Product of Water in the Eye of the Quantum Cluster Equilibrium. Molecules 2022; 27:molecules27041286. [PMID: 35209075 PMCID: PMC8877775 DOI: 10.3390/molecules27041286] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 02/06/2022] [Accepted: 02/09/2022] [Indexed: 11/16/2022] Open
Abstract
The theoretical description of water properties continues to be a challenge. Using quantum cluster equilibrium (QCE) theory, we combine state-of-the-art quantum chemistry and statistical thermodynamic methods with the almost historical Clausius-Clapeyron relation to study water self-dissociation and the thermodynamics of vaporization. We pay particular attention to the treatment of internal rotations and their impact on the investigated properties by employing the modified rigid-rotor-harmonic-oscillator (mRRHO) approach. We also study a novel QCE parameter-optimization procedure. Both the ionic product and the vaporization enthalpy yield an astonishing agreement with experimental reference data. A significant influence of the mRRHO approach is observed for cluster populations and, consequently, for the ionic product. Thermodynamic properties are less affected by the treatment of these low-frequency modes.
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Affiliation(s)
- Barbara Kirchner
- Mulliken Center for Theoretical Chemistry, Institute for Physical and Theoretical Chemistry, Beringstr. 4, 53115 Bonn, Germany
- Correspondence:
| | - Johannes Ingenmey
- CNRS, Physico-Chimie des Électrolytes et Nanosystèmes Interfaciaux, Sorbonne Université, F-75005 Paris, France;
| | - Michael von Domaros
- Department of Chemistry, Philipps-Universität Marburg, Hans-Meerwein-Straße 4, 35032 Marburg, Germany;
| | - Eva Perlt
- Otto Schott Institute of Materials Research, Faculty of Physics and Astronomy, Friedrich-Schiller-Universität Jena, Löbdergraben 32, 07743 Jena, Germany;
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33
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Yang Y, Peltier CR, Zeng R, Schimmenti R, Li Q, Huang X, Yan Z, Potsi G, Selhorst R, Lu X, Xu W, Tader M, Soudackov AV, Zhang H, Krumov M, Murray E, Xu P, Hitt J, Xu L, Ko HY, Ernst BG, Bundschu C, Luo A, Markovich D, Hu M, He C, Wang H, Fang J, DiStasio RA, Kourkoutis LF, Singer A, Noonan KJT, Xiao L, Zhuang L, Pivovar BS, Zelenay P, Herrero E, Feliu JM, Suntivich J, Giannelis EP, Hammes-Schiffer S, Arias T, Mavrikakis M, Mallouk TE, Brock JD, Muller DA, DiSalvo FJ, Coates GW, Abruña HD. Electrocatalysis in Alkaline Media and Alkaline Membrane-Based Energy Technologies. Chem Rev 2022; 122:6117-6321. [PMID: 35133808 DOI: 10.1021/acs.chemrev.1c00331] [Citation(s) in RCA: 89] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Hydrogen energy-based electrochemical energy conversion technologies offer the promise of enabling a transition of the global energy landscape from fossil fuels to renewable energy. Here, we present a comprehensive review of the fundamentals of electrocatalysis in alkaline media and applications in alkaline-based energy technologies, particularly alkaline fuel cells and water electrolyzers. Anion exchange (alkaline) membrane fuel cells (AEMFCs) enable the use of nonprecious electrocatalysts for the sluggish oxygen reduction reaction (ORR), relative to proton exchange membrane fuel cells (PEMFCs), which require Pt-based electrocatalysts. However, the hydrogen oxidation reaction (HOR) kinetics is significantly slower in alkaline media than in acidic media. Understanding these phenomena requires applying theoretical and experimental methods to unravel molecular-level thermodynamics and kinetics of hydrogen and oxygen electrocatalysis and, particularly, the proton-coupled electron transfer (PCET) process that takes place in a proton-deficient alkaline media. Extensive electrochemical and spectroscopic studies, on single-crystal Pt and metal oxides, have contributed to the development of activity descriptors, as well as the identification of the nature of active sites, and the rate-determining steps of the HOR and ORR. Among these, the structure and reactivity of interfacial water serve as key potential and pH-dependent kinetic factors that are helping elucidate the origins of the HOR and ORR activity differences in acids and bases. Additionally, deliberately modulating and controlling catalyst-support interactions have provided valuable insights for enhancing catalyst accessibility and durability during operation. The design and synthesis of highly conductive and durable alkaline membranes/ionomers have enabled AEMFCs to reach initial performance metrics equal to or higher than those of PEMFCs. We emphasize the importance of using membrane electrode assemblies (MEAs) to integrate the often separately pursued/optimized electrocatalyst/support and membranes/ionomer components. Operando/in situ methods, at multiscales, and ab initio simulations provide a mechanistic understanding of electron, ion, and mass transport at catalyst/ionomer/membrane interfaces and the necessary guidance to achieve fuel cell operation in air over thousands of hours. We hope that this Review will serve as a roadmap for advancing the scientific understanding of the fundamental factors governing electrochemical energy conversion in alkaline media with the ultimate goal of achieving ultralow Pt or precious-metal-free high-performance and durable alkaline fuel cells and related technologies.
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Affiliation(s)
- Yao Yang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Cheyenne R Peltier
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Rui Zeng
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Roberto Schimmenti
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Qihao Li
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Xin Huang
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - Zhifei Yan
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Georgia Potsi
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Ryan Selhorst
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Xinyao Lu
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Weixuan Xu
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Mariel Tader
- Department of Physics, Cornell University, Ithaca, New York 14853, United States
| | - Alexander V Soudackov
- Department of Chemistry, Yale University, New Haven, Connecticut 06520, United States
| | - Hanguang Zhang
- Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Mihail Krumov
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Ellen Murray
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Pengtao Xu
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Jeremy Hitt
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Linxi Xu
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Hsin-Yu Ko
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Brian G Ernst
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Colin Bundschu
- Department of Physics, Cornell University, Ithaca, New York 14853, United States
| | - Aileen Luo
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Danielle Markovich
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - Meixue Hu
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Cheng He
- Chemical and Materials Science Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Hongsen Wang
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Jiye Fang
- Department of Chemistry, State University of New York at Binghamton, Binghamton, New York 13902, United States
| | - Robert A DiStasio
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Lena F Kourkoutis
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States.,Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Andrej Singer
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | - Kevin J T Noonan
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Li Xiao
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Lin Zhuang
- College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China
| | - Bryan S Pivovar
- Chemical and Materials Science Center, National Renewable Energy Laboratory, Golden, Colorado 80401, United States
| | - Piotr Zelenay
- Materials Physics and Applications Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States
| | - Enrique Herrero
- Instituto de Electroquímica, Universidad de Alicante, Alicante E-03080, Spain
| | - Juan M Feliu
- Instituto de Electroquímica, Universidad de Alicante, Alicante E-03080, Spain
| | - Jin Suntivich
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States.,Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Emmanuel P Giannelis
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States
| | | | - Tomás Arias
- Department of Physics, Cornell University, Ithaca, New York 14853, United States
| | - Manos Mavrikakis
- Department of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Thomas E Mallouk
- Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Joel D Brock
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States
| | - David A Muller
- School of Applied and Engineering Physics, Cornell University, Ithaca, New York 14853, United States.,Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14853, United States
| | - Francis J DiSalvo
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Geoffrey W Coates
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States
| | - Héctor D Abruña
- Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, United States.,Center for Alkaline Based Energy Solutions (CABES), Cornell University, Ithaca, New York 14853, United States
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34
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Ye Z, Zhang C, Galli G. Photoelectron spectra of water and simple aqueous solutions at extreme conditions. Faraday Discuss 2022; 236:352-363. [DOI: 10.1039/d2fd00003b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Determining the electronic structure of aqueous solutions at extreme conditions is an important step towards understanding chemical bonding and reactions in water under pressure (P) and at high temperature (T)....
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35
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Jinnouchi R. Molecular dynamics simulations of proton conducting mediums containing phosphoric acid. Phys Chem Chem Phys 2022; 24:15522-15531. [DOI: 10.1039/d2cp00484d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
An anhydrous proton conducting electrolyte is a key material to realise medium-temperature fuel cells that can drastically simplify heat radiation systems in transportation applications. However, practical applications are limited by...
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36
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Adams EM, Hao H, Leven I, Rüttermann M, Wirtz H, Havenith M, Head‐Gordon T. Proton Traffic Jam: Effect of Nanoconfinement and Acid Concentration on Proton Hopping Mechanism. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202108766] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Ellen M. Adams
- Lehrstuhl für Physkalische Chemie II Ruhr Universität Bochum 44801 Bochum Germany
| | - Hongxia Hao
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA
- Kenneth S. Pitzer Center for Theoretical Chemistry University of California Berkeley California 94720 USA
- Department of Chemistry University of California Berkeley California 94720 USA
| | - Itai Leven
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA
- Kenneth S. Pitzer Center for Theoretical Chemistry University of California Berkeley California 94720 USA
- Department of Chemistry University of California Berkeley California 94720 USA
| | | | - Hanna Wirtz
- Lehrstuhl für Physkalische Chemie II Ruhr Universität Bochum 44801 Bochum Germany
| | - Martina Havenith
- Lehrstuhl für Physkalische Chemie II Ruhr Universität Bochum 44801 Bochum Germany
| | - Teresa Head‐Gordon
- Chemical Sciences Division Lawrence Berkeley National Laboratory Berkeley California 94720 USA
- Kenneth S. Pitzer Center for Theoretical Chemistry University of California Berkeley California 94720 USA
- Department of Chemistry University of California Berkeley California 94720 USA
- Department of Chemical and Biomolecular Engineering University of California Berkeley California 94720 USA
- Department of Bioengineering University of California Berkeley California 94720 USA
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37
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Ohmine I, Saito S. Dynamical Behavior of Water; Fluctuation, Reactions and Phase Transitions. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2021. [DOI: 10.1246/bcsj.20210269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Iwao Ohmine
- Institute for Molecular Science, Myodaiji, Okazaki, Aichi 444-8585, Japan
| | - Shinji Saito
- Institute for Molecular Science, Myodaiji, Okazaki, Aichi 444-8585, Japan
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38
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Calio PB, Li C, Voth GA. Resolving the Structural Debate for the Hydrated Excess Proton in Water. J Am Chem Soc 2021; 143:18672-18683. [PMID: 34723507 DOI: 10.1021/jacs.1c08552] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
It has long been proposed that the hydrated excess proton in water (aka the solvated "hydronium" cation) likely has two limiting forms, that of the Eigen cation (H9O4+) and that of the Zundel cation (H5O2+). There has been debate over which of these two is the more dominant species and/or whether intermediate (or "distorted") structures between these two limits are the more realistic representation. Spectroscopy experiments have recently provided further results regarding the excess proton. These experiments show that the hydrated proton has an anisotropy reorientation time scale on the order of 1-2 ps. This time scale has been suggested to possibly contradict the picture of the more rapid "special pair dance" phenomenon for the hydrated excess proton, which is a signature of a distorted Eigen cation. The special pair dance was predicted from prior computational studies in which the hydrated central core hydronium structure continually switches (O-H···O)* special pair hydrogen-bond partners with the closest three water molecules, yielding on average a distorted Eigen cation with three equivalent and dynamically exchanging distortions. Through state-of-art simulations it is shown here that anisotropy reorientation time scales of the same magnitude are obtained that also include structural reorientations associated with the special pair dance, leading to a reinterpretation of the experimental results. These results and additional analyses point to a distorted and dynamic Eigen cation as the most prevalent hydrated proton species in aqueous acid solutions of dilute to moderate concentration, as opposed to a stabilized or a distorted (but not "dancing") Zundel cation.
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Affiliation(s)
- Paul B Calio
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
| | - Chenghan Li
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
| | - Gregory A Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, 5735 South Ellis Avenue, Chicago, Illinois 60637, United States
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39
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Atsango AO, Tuckerman ME, Markland TE. Characterizing and Contrasting Structural Proton Transport Mechanisms in Azole Hydrogen Bond Networks Using Ab Initio Molecular Dynamics. J Phys Chem Lett 2021; 12:8749-8756. [PMID: 34478302 DOI: 10.1021/acs.jpclett.1c02266] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Imidazole and 1,2,3-triazole are promising hydrogen-bonded heterocycles that conduct protons via a structural mechanism and whose derivatives are present in systems ranging from biological proton channels to proton exchange membrane fuel cells. Here, we leverage multiple time-stepping to perform ab initio molecular dynamics of imidazole and 1,2,3-triazole at the nanosecond time scale. We show that despite the close structural similarities of these compounds, their proton diffusion constants vary by over an order of magnitude. Our simulations reveal the reasons for these differences in diffusion constants, which range from the degree of hydrogen-bonded chain linearity to the effect of the central nitrogen atom in 1,2,3-triazole on proton transport. In particular, we uncover evidence of two "blocking" mechanisms in 1,2,3-triazole, where covalent and hydrogen bonds formed by the central nitrogen atom limit the mobility of protons. Our simulations thus provide insights into the origins of the experimentally observed 10-fold difference in proton conductivity.
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Affiliation(s)
- Austin O Atsango
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
| | - Mark E Tuckerman
- Department of Chemistry, New York University, New York, New York 10003, United States
- Courant Institute of Mathematical Science, New York University, New York, New York 10012, United States
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, 3663 Zhongshan Road North, Shanghai 200062, China
| | - Thomas E Markland
- Department of Chemistry, Stanford University, Stanford, California 94305, United States
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40
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Batista PR, Penna TC, Ducati LC, Correra TC. p-Aminobenzoic acid protonation dynamics in an evaporating droplet by ab initio molecular dynamics. Phys Chem Chem Phys 2021; 23:19659-19672. [PMID: 34524295 DOI: 10.1039/d1cp01495a] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Protonation equilibria are known to vary from the bulk to microdroplet conditions, which could induce many chemical and physical phenomena. Protonated p-aminobenzoic acid (PABA + H+) can be considered a model for probing the protonation dynamics in an evaporating droplet, as its protonation equilibrium is highly dependent on the formation conditions from solution via atmospheric pressure ionization sources. Experiments using diverse experimental techniques have shown that protic solvents allow formation of the O-protomer (PABA protonated in the carboxylic acid group) stable in the gas phase, while aprotic solvents yield the N-protomer (protonated in the amino group) that is the most stable protomer in solution. In this work, we explore the protonation equilibrium of PABA solvated by different numbers of water molecules (n = 0 to 32) using ab initio molecular dynamics. For n = 8-32, the protonation is either at the NH2 group or in the solvent network. The solvent network interacts with the carboxylic acid group, but there is no complete proton transfer to form the O-protomer. For smaller clusters, however, solvent-mediated proton transfers to the carboxylic acid were observed, both via the Grotthuss mechanism and the vehicle or shuttle mechanism (for n = 1 and 2). Thermodynamic considerations allowed a description of the origins of the kinetic trapping effect, which explains the observation of the solution structure in the gas phase. This effect likely occurs in the final evaporation steps, which are outside the droplet size range covered by previous classical molecular dynamics simulations of charged droplets. These results may be considered relevant in determining the nature of the species observed in the ubiquitous ESI based mass spectrometry analysis, and in general for droplet chemistry, explaining how protonation equilibria are drastically changed from bulk to microdroplet conditions.
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Affiliation(s)
- Patrick R Batista
- Department of Fundamental Chemistry, Institute of Chemistry - University of São Paulo, Av. Prof. Lineu Prestes, 748, Cidade Universitária, São Paulo, SP, Brazil.
| | - Tatiana C Penna
- Department of Fundamental Chemistry, Institute of Chemistry - University of São Paulo, Av. Prof. Lineu Prestes, 748, Cidade Universitária, São Paulo, SP, Brazil.
| | - Lucas C Ducati
- Department of Fundamental Chemistry, Institute of Chemistry - University of São Paulo, Av. Prof. Lineu Prestes, 748, Cidade Universitária, São Paulo, SP, Brazil.
| | - Thiago C Correra
- Department of Fundamental Chemistry, Institute of Chemistry - University of São Paulo, Av. Prof. Lineu Prestes, 748, Cidade Universitária, São Paulo, SP, Brazil.
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41
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Chen Y, Zhang X, Qin J, Liu R. High-throughput screening of single metal atom anchored on N-doped boron phosphide for N 2 reduction. NANOSCALE 2021; 13:13437-13450. [PMID: 34477749 DOI: 10.1039/d1nr02883a] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Developing eco-friendly and highly-efficient catalysts for the electrochemical nitrogen reduction reaction (NRR) under ambient conditions to replace the energy-intensive and environment-polluting Haber-Bosch process is of great significance, while remaining a long-standing challenge in the field of energy conversion today. Herein, through the first principles high-throughput screening, we systematically investigated the catalytic activity of a series of single metal atom immobilized on N-doped boron phosphide (N3-BP) for N2 reduction, denoted as MN3-BP. In particular, a "four-step" screening strategy, involving the structural stability, N2 chemisorption, low energy cost, as well as good selectivity, was adopted for the stringent screening of the promising MN3-BP candidates for NRR. Our results unveil that among these candidates, MoN3-BP eventually stands out, benefiting from its high selectivity and activity, as well as accompanying a considerably favorable limiting potential of -0.25 V for NRR. More impressively, the NRR activity origin of various candidates was revealed by the descriptor φ and ICOHP. Overall, our work not only accelerates the discovery of SACs for converting N2 into sustainable NH3 but also provides an exciting impetus for the rational design of NRR catalysts with high stability, high activity, and high selectivity.
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Affiliation(s)
- Yibo Chen
- State Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, Hebei, China.
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42
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Havenith-Newen M, Adams EM, Head-Gordon T, Hao H, Rüttermann M, Leven I, Wirtz H. Proton Traffic Jam: Effect of Nanoconfinement and Acid Concentration on Proton Hopping Mechanism. Angew Chem Int Ed Engl 2021; 60:25419-25427. [PMID: 34402145 PMCID: PMC9293324 DOI: 10.1002/anie.202108766] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2021] [Indexed: 11/06/2022]
Abstract
The properties of the water network in concentrated HCl acid pools in nanometer-sized reverse non-ionic micelles were probed with TeraHertz absorption, dielectric relaxation spectroscopy, and reactive force field simulations capable of describing proton hopping mechanisms. We identify that only at a critical micelle size of W0=9 do solvated proton complexes form in the water pool, accompanied by a change in mechanism from Grotthuss forward shuttling to one that favors local oscillatory hopping. This is due to a preference for H+ and Cl- ions to adsorb to the micelle interface, together with an acid concentration effect that causes a "traffic jam" in which the short-circuiting of the hydrogen-bonding motif of the hydronium ion decreases the forward hopping rate throughout the water interior even as the micelle size increases. These findings have implications for atmospheric chemistry, biochemical and biophysical environments, and energy materials, as transport of protons vital to these processes can be suppressed due to confinement, aggregation, and/or concentration.
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Affiliation(s)
- Martina Havenith-Newen
- Ruhr-Universit�t Bochum, Physical Chemistry, Universit�tsstr. 150, 44780, Bochum, GERMANY
| | - Ellen M Adams
- Ruhr-Universität Bochum: Ruhr-Universitat Bochum, Chemistry and Biochemistry, GERMANY
| | - Teresa Head-Gordon
- UC Berkeley: University of California Berkeley, Chemistry, UNITED STATES
| | - Hongxia Hao
- Berkeley Laboratory: E O Lawrence Berkeley National Laboratory, Chemistry, UNITED STATES
| | | | - Itai Leven
- Lawrence Livermore National Laboratory, chemistry, GERMANY
| | - Hanna Wirtz
- Ruhr-Universität Bochum: Ruhr-Universitat Bochum, Chemistry, GERMANY
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43
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Opoku E, Pawłowski F, Ortiz JV. Electron binding energies and Dyson orbitals of O nH 2n+1 +,0,- clusters: Double Rydberg anions, Rydberg radicals, and micro-solvated hydronium cations. J Chem Phys 2021; 154:234304. [PMID: 34241254 DOI: 10.1063/5.0053297] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Ab initio electron propagator methods are employed to predict the vertical electron attachment energies (VEAEs) of OH3 +(H2O)n clusters. The VEAEs decrease with increasing n, and the corresponding Dyson orbitals are diffused over exterior, non-hydrogen bonded protons. Clusters formed from OH3 - double Rydberg anions (DRAs) and stabilized by hydrogen bonding or electrostatic interactions between ions and polar molecules are studied through calculations on OH3 -(H2O)n complexes and are compared with more stable H-(H2O)n+1 isomers. Remarkable changes in the geometry of the anionic hydronium-water clusters with respect to their cationic counterparts occur. Rydberg electrons in the uncharged and anionic clusters are held near the exterior protons of the water network. For all values of n, the anion-water complex H-(H2O)n+1 is always the most stable, with large vertical electron detachment energies (VEDEs). OH3 -(H2O)n DRA isomers have well separated VEDEs and may be visible in anion photoelectron spectra. Corresponding Dyson orbitals occupy regions beyond the peripheral O-H bonds and differ significantly from those obtained for the VEAEs of the cations.
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Affiliation(s)
- Ernest Opoku
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849-5312, USA
| | - Filip Pawłowski
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849-5312, USA
| | - Joseph Vincent Ortiz
- Department of Chemistry and Biochemistry, Auburn University, Auburn, Alabama 36849-5312, USA
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44
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Arntsen C, Chen C, Calio PB, Li C, Voth GA. The hopping mechanism of the hydrated excess proton and its contribution to proton diffusion in water. J Chem Phys 2021; 154:194506. [PMID: 34240917 DOI: 10.1063/5.0040758] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
In this work, a series of analyses are performed on ab initio molecular dynamics simulations of a hydrated excess proton in water to quantify the relative occurrence of concerted hopping events and "rattling" events and thus to further elucidate the hopping mechanism of proton transport in water. Contrary to results reported in certain earlier papers, the new analysis finds that concerted hopping events do occur in all simulations but that the majority of events are the product of proton rattling, where the excess proton will rattle between two or more waters. The results are consistent with the proposed "special-pair dance" model of the hydrated excess proton wherein the acceptor water molecule for the proton transfer will quickly change (resonate between three equivalent special pairs) until a decisive proton hop occurs. To remove the misleading effect of simple rattling, a filter was applied to the trajectory such that hopping events that were followed by back hops to the original water are not counted. A steep reduction in the number of multiple hopping events is found when the filter is applied, suggesting that many multiple hopping events that occur in the unfiltered trajectory are largely the product of rattling, contrary to prior suggestions. Comparing the continuous correlation function of the filtered and unfiltered trajectories, we find agreement with experimental values for the proton hopping time and Eigen-Zundel interconversion time, respectively.
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Affiliation(s)
- Christopher Arntsen
- Department of Chemistry, Youngstown State University, Youngstown, Ohio 44555, USA
| | - Chen Chen
- Department of Mechanical and Nuclear Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Paul B Calio
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
| | - Chenghan Li
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
| | - Gregory A Voth
- Department of Chemistry, Chicago Center for Theoretical Chemistry, James Franck Institute, and Institute for Biophysical Dynamics, The University of Chicago, Chicago, Illinois 60637, USA
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45
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Zelovich T, Tuckerman ME. OH - and H 3O + Diffusion in Model AEMs and PEMs at Low Hydration: Insights from Ab Initio Molecular Dynamics. MEMBRANES 2021; 11:355. [PMID: 34066142 PMCID: PMC8151131 DOI: 10.3390/membranes11050355] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 04/25/2021] [Accepted: 05/06/2021] [Indexed: 11/27/2022]
Abstract
Fuel cell-based anion-exchange membranes (AEMs) and proton exchange membranes (PEMs) are considered to have great potential as cost-effective, clean energy conversion devices. However, a fundamental atomistic understanding of the hydroxide and hydronium diffusion mechanisms in the AEM and PEM environment is an ongoing challenge. In this work, we aim to identify the fundamental atomistic steps governing hydroxide and hydronium transport phenomena. The motivation of this work lies in the fact that elucidating the key design differences between the hydroxide and hydronium diffusion mechanisms will play an important role in the discovery and determination of key design principles for the synthesis of new membrane materials with high ion conductivity for use in emerging fuel cell technologies. To this end, ab initio molecular dynamics simulations are presented to explore hydroxide and hydronium ion solvation complexes and diffusion mechanisms in the model AEM and PEM systems at low hydration in confined environments. We find that hydroxide diffusion in AEMs is mostly vehicular, while hydronium diffusion in model PEMs is structural. Furthermore, we find that the region between each pair of cations in AEMs creates a bottleneck for hydroxide diffusion, leading to a suppression of diffusivity, while the anions in PEMs become active participants in the hydronium diffusion, suggesting that the presence of the anions in model PEMs could potentially promote hydronium diffusion.
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Affiliation(s)
- Tamar Zelovich
- Department of Chemistry, New York University (NYU), New York 10003, NY, USA
| | - Mark E. Tuckerman
- Department of Chemistry, New York University (NYU), New York 10003, NY, USA
- Courant Institute of Mathematical Sciences, New York University (NYU), New York, NY 10012, USA
- NYU-ECNU Center for Computational Chemistry at NYU Shanghai, 3663 Zhongshan Rd. North, Shanghai 200062, China
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46
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Kim YL, Han Y, Evans JW, Gordon MS. Effective Fragment Potential-Based Molecular Dynamics Studies of Diffusion in Acetone and Hexane. J Phys Chem A 2021; 125:3398-3405. [PMID: 33861600 DOI: 10.1021/acs.jpca.1c01865] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To facilitate more reliable descriptions of transport properties in liquids, molecular dynamics (MD) simulations are performed based on the effective fragment potential (EFP) method derived from first-principles quantum mechanics (in contrast to MD based upon empirically fitted potentials). The EFP method describes molecular interactions in terms of Coulomb, polarization/induction, dispersion, exchange-repulsion, and charge-transfer interactions. The EFP MD simulations described in this paper, performed on hexane and acetone, are able to track the mean-square displacement of molecules for sufficient time to reliably extract translational diffusion coefficients. The results reported here are in reasonable agreement with experiment.
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Affiliation(s)
- Yu Lim Kim
- Ames Laboratory, US Department of Energy, Iowa State University, Ames, Iowa 50011, United States.,Department of Chemistry, Iowa State University, Ames, Iowa 50010, United States
| | - Yong Han
- Ames Laboratory, US Department of Energy, Iowa State University, Ames, Iowa 50011, United States.,Department of Physics & Astronomy, Iowa State University, Ames, Iowa 50010, United States
| | - James W Evans
- Ames Laboratory, US Department of Energy, Iowa State University, Ames, Iowa 50011, United States.,Department of Physics & Astronomy, Iowa State University, Ames, Iowa 50010, United States
| | - Mark S Gordon
- Ames Laboratory, US Department of Energy, Iowa State University, Ames, Iowa 50011, United States.,Department of Chemistry, Iowa State University, Ames, Iowa 50010, United States
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47
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Zeng HJ, Johnson MA. Demystifying the Diffuse Vibrational Spectrum of Aqueous Protons Through Cold Cluster Spectroscopy. Annu Rev Phys Chem 2021; 72:667-691. [PMID: 33646816 DOI: 10.1146/annurev-physchem-061020-053456] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The ease with which the pH is routinely determined for aqueous solutions masks the fact that the cationic product of Arrhenius acid dissolution, the hydrated proton, or H+(aq), is a remarkably complex species. Here, we review how results obtained over the past 30 years in the study of H+⋅(H2O)n cluster ions isolated in the gas phase shed light on the chemical nature of H+(aq). This effort has also revealed molecular-level aspects of the Grotthuss relay mechanism for positive-charge translocation in water. Recently developed methods involving cryogenic cooling in radiofrequency ion traps and the application of two-color, infrared-infrared (IR-IR) double-resonance spectroscopy have established a clear picture of how local hydrogen-bond topology drives the diverse spectral signatures of the excess proton. This information now enables a new generation of cluster studies designed to unravel the microscopic mechanics underlying the ultrafast relaxation dynamics displayed by H+(aq).
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Affiliation(s)
- Helen J Zeng
- Sterling Chemistry Laboratory, Yale University, New Haven, Connecticut 06520, USA;
| | - Mark A Johnson
- Sterling Chemistry Laboratory, Yale University, New Haven, Connecticut 06520, USA;
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48
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Watanabe HC, Yamada M, Suzuki Y. Proton transfer in bulk water using the full adaptive QM/MM method: integration of solute- and solvent-adaptive approaches. Phys Chem Chem Phys 2021; 23:8344-8360. [PMID: 33875999 DOI: 10.1039/d1cp00116g] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The quantum mechanical/molecular mechanical (QM/MM) method is a hybrid molecular simulation technique that increases the accessibility of local electronic structures of large systems. The technique combines the benefit of accuracy found in the QM method and that of cost efficiency found in the MM method. However, it is difficult to directly apply the QM/MM method to the dynamics of solution systems, particularly for proton transfer. As explained in the Grotthuss mechanism, proton transfer is a structural interconversion between hydronium ions and solvent water molecules. Hence, when the QM/MM method is applied, an adaptive treatment, namely on-the-fly revisions on molecular definitions, is required for both the solute and solvent. Although several solvent-adaptive methods have been proposed, a full adaptive framework, which is an approach that also considers adaptation for solutes, remains untapped. In this paper, we propose a new numerical expression for the coordinates of the excess proton and its control algorithm. Furthermore, we confirm that this method can stably and accurately simulate proton transfer dynamics in bulk water.
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Affiliation(s)
- Hiroshi C Watanabe
- Quantum Computing Center, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan.
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49
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Gelenter MD, Mandala VS, Niesen MJM, Sharon DA, Dregni AJ, Willard AP, Hong M. Water orientation and dynamics in the closed and open influenza B virus M2 proton channels. Commun Biol 2021; 4:338. [PMID: 33712696 PMCID: PMC7955094 DOI: 10.1038/s42003-021-01847-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 02/11/2021] [Indexed: 01/03/2023] Open
Abstract
The influenza B M2 protein forms a water-filled tetrameric channel to conduct protons across the lipid membrane. To understand how channel water mediates proton transport, we have investigated the water orientation and dynamics using solid-state NMR spectroscopy and molecular dynamics (MD) simulations. 13C-detected water 1H NMR relaxation times indicate that water has faster rotational motion in the low-pH open channel than in the high-pH closed channel. Despite this faster dynamics, the open-channel water shows higher orientational order, as manifested by larger motionally-averaged 1H chemical shift anisotropies. MD simulations indicate that this order is induced by the cationic proton-selective histidine at low pH. Furthermore, the water network has fewer hydrogen-bonding bottlenecks in the open state than in the closed state. Thus, faster dynamics and higher orientational order of water molecules in the open channel establish the water network structure that is necessary for proton hopping.
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Affiliation(s)
- Martin D Gelenter
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Venkata S Mandala
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Michiel J M Niesen
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Dina A Sharon
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Aurelio J Dregni
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Adam P Willard
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Mei Hong
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA, USA.
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50
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Dieckhöfer S, Öhl D, Junqueira JRC, Quast T, Turek T, Schuhmann W. Probing the Local Reaction Environment During High Turnover Carbon Dioxide Reduction with Ag-Based Gas Diffusion Electrodes. Chemistry 2021; 27:5906-5912. [PMID: 33527522 PMCID: PMC8048634 DOI: 10.1002/chem.202100387] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Indexed: 01/03/2023]
Abstract
Discerning the influence of electrochemical reactions on the electrode microenvironment is an unavoidable topic for electrochemical reactions that involve the production of OH− and the consumption of water. That is particularly true for the carbon dioxide reduction reaction (CO2RR), which together with the competing hydrogen evolution reaction (HER) exert changes in the local OH− and H2O activity that in turn can possibly affect activity, stability, and selectivity of the CO2RR. We determine the local OH− and H2O activity in close proximity to a CO2‐converting Ag‐based gas diffusion electrode (GDE) with product analysis using gas chromatography. A Pt nanosensor is positioned in the vicinity of the working GDE using shear‐force‐based scanning electrochemical microscopy (SECM) approach curves, which allows monitoring changes invoked by reactions proceeding within an otherwise inaccessible porous GDE by potentiodynamic measurements at the Pt‐tip nanosensor. We show that high turnover HER/CO2RR at a GDE lead to modulations of the alkalinity of the local electrolyte, that resemble a 16 m KOH solution, variations that are in turn linked to the reaction selectivity.
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Affiliation(s)
- Stefan Dieckhöfer
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - Denis Öhl
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - João R C Junqueira
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - Thomas Quast
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, 44780, Bochum, Germany
| | - Thomas Turek
- Institute of Chemical and Electrochemical Process Engineering, Clausthal University of Technology, Leibnizstr 17, 38678, Clausthal-Zellerfeld, Germany
| | - Wolfgang Schuhmann
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, 44780, Bochum, Germany
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