1
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Chen X, Ojha K, Koper MTM. Deconvolution of the Voltammetric Features of a Pt(100) Single-Crystal Electrode. J Phys Chem Lett 2024; 15:4958-4964. [PMID: 38687840 PMCID: PMC11089564 DOI: 10.1021/acs.jpclett.4c01056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2024] [Revised: 04/26/2024] [Accepted: 04/26/2024] [Indexed: 05/02/2024]
Abstract
The Pt(100) single-crystal electrode shows four voltammetric features in acid electrolytes, but the precise corresponding surface phenomena remain unresolved. Herein, a deconvolution of the classical "hydrogen region" from the "hydroxyl and anion region" is attempted by the comparison of voltammetric behavior of Pt(100) and GMLPt(100) electrodes. A systematic study performed on Pt(s)-[n(100) × (111)] and Pt(s)-[n(100) × (110)] electrodes reveals that the feature at EPI = 0.30 VRHE corresponds to pure hydrogen adsorption taking place at (111) step sites vicinal to (100) domains, while the peak at EPII = 0.36 VRHE actually involves hydroxyl replacing hydrogen at (100) domains. An analysis examined for H2SO4, HClO4, CH3SO3H, and HF demonstrates that the specific (H)SO4- adsorption commences at EPIII = 0.40 VRHE and effectively suppresses the formation of hydroxyl at the (100) terrace at higher potentials 0.40 < EPIV < 0.75 VRHE. Non-specifically adsorbing anions (ClO4-, CH3SO3- and F-) would only interact with the hydroxyl phase formed on the Pt(100) terrace in both potential regions.
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Affiliation(s)
- Xiaoting Chen
- School
of Materials Science and Engineering, Beijing
Institute of Technology, Beijing 100081, P.
R. China
- Leiden Institute
of Chemistry, Leiden University, P. O. Box 9502, 2300 RA, Leiden, The Netherlands
| | - Kasinath Ojha
- Leiden Institute
of Chemistry, Leiden University, P. O. Box 9502, 2300 RA, Leiden, The Netherlands
| | - Marc T. M. Koper
- Leiden Institute
of Chemistry, Leiden University, P. O. Box 9502, 2300 RA, Leiden, The Netherlands
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2
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Mohandas N, Bawari S, Shibuya JJT, Ghosh S, Mondal J, Narayanan TN, Cuesta A. Understanding electrochemical interfaces through comparing experimental and computational charge density-potential curves. Chem Sci 2024; 15:6643-6660. [PMID: 38725490 PMCID: PMC11077530 DOI: 10.1039/d4sc00746h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 04/21/2024] [Indexed: 05/12/2024] Open
Abstract
Electrode-electrolyte interfaces play a decisive role in electrochemical charge accumulation and transfer processes. Theoretical modelling of these interfaces is critical to decipher the microscopic details of such phenomena. Different force field-based molecular dynamics protocols are compared here in a view to connect calculated and experimental charge density-potential relationships. Platinum-aqueous electrolyte interfaces are taken as a model. The potential of using experimental charge density-potential curves to transform cell voltage into electrode potential in force-field molecular dynamics simulations, and the need for that purpose of developing simulation protocols that can accurately calculate the double-layer capacitance, are discussed.
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Affiliation(s)
- Nandita Mohandas
- Tata Institute of Fundamental Research-Hyderabad Hyderabad 500046 India
- Advanced Centre for Energy and Sustainability (ACES), School of Natural and Computing Sciences, University of Aberdeen AB24 3UE Aberdeen Scotland UK
| | - Sumit Bawari
- Tata Institute of Fundamental Research-Hyderabad Hyderabad 500046 India
| | - Jani J T Shibuya
- Advanced Centre for Energy and Sustainability (ACES), School of Natural and Computing Sciences, University of Aberdeen AB24 3UE Aberdeen Scotland UK
| | - Soumya Ghosh
- Tata Institute of Fundamental Research-Hyderabad Hyderabad 500046 India
| | - Jagannath Mondal
- Tata Institute of Fundamental Research-Hyderabad Hyderabad 500046 India
| | | | - Angel Cuesta
- Advanced Centre for Energy and Sustainability (ACES), School of Natural and Computing Sciences, University of Aberdeen AB24 3UE Aberdeen Scotland UK
- Centre for Energy Transition, University of Aberdeen AB24 3FX Aberdeen Scotland UK
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3
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Liang C, Katayama Y, Tao Y, Morinaga A, Moss B, Celorrio V, Ryan M, Stephens IEL, Durrant JR, Rao RR. Role of Electrolyte pH on Water Oxidation for Iridium Oxides. J Am Chem Soc 2024; 146:8928-8938. [PMID: 38526298 PMCID: PMC10996014 DOI: 10.1021/jacs.3c12011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Revised: 03/06/2024] [Accepted: 03/07/2024] [Indexed: 03/26/2024]
Abstract
Understanding the effect of noncovalent interactions of intermediates at the polarized catalyst-electrolyte interface on water oxidation kinetics is key for designing more active and stable electrocatalysts. Here, we combine operando optical spectroscopy, X-ray absorption spectroscopy (XAS), and surface-enhanced infrared absorption spectroscopy (SEIRAS) to probe the effect of noncovalent interactions on the oxygen evolution reaction (OER) activity of IrOx in acidic and alkaline electrolytes. Our results suggest that the active species for the OER (Ir4.x+-*O) binds much stronger in alkaline compared with acid at low coverage, while the repulsive interactions between these species are higher in alkaline electrolytes. These differences are attributed to the larger fraction of water within the cation hydration shell at the interface in alkaline electrolytes compared to acidic electrolytes, which can stabilize oxygenated intermediates and facilitate long-range interactions between them. Quantitative analysis of the state energetics shows that although the *O intermediates bind more strongly than optimal in alkaline electrolytes, the larger repulsive interaction between them results in a significant weakening of *O binding with increasing coverage, leading to similar energetics of active states in acid and alkaline at OER-relevant potentials. By directly probing the electrochemical interface with complementary spectroscopic techniques, our work goes beyond conventional computational descriptors of the OER activity to explain the experimentally observed OER kinetics of IrOx in acidic and alkaline electrolytes.
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Affiliation(s)
- Caiwu Liang
- Department of
Materials, Imperial College London, Exhibition Road, SW72AZ London, United Kingdom
| | - Yu Katayama
- Department
of Energy and Environmental Materials, SANKEN (The Institute of Scientific
and Industrial Research), Osaka University, Mihogaoka 8-1, Osaka 567-0047, Ibaraki, Japan
| | - Yemin Tao
- Department of
Materials, Imperial College London, Exhibition Road, SW72AZ London, United Kingdom
| | - Asuka Morinaga
- Department
of Energy and Environmental Materials, SANKEN (The Institute of Scientific
and Industrial Research), Osaka University, Mihogaoka 8-1, Osaka 567-0047, Ibaraki, Japan
| | - Benjamin Moss
- Department
of Chemistry, Centre for Processable Electronics, Imperial College London, White city campus, W12 0BZ London, United Kingdom
| | - Verónica Celorrio
- Diamond
Light Source, Harwell Science and Innovation Campus, Didcot OX11 0DE, United
Kingdom
| | - Mary Ryan
- Department of
Materials, Imperial College London, Exhibition Road, SW72AZ London, United Kingdom
| | - Ifan E. L. Stephens
- Department of
Materials, Imperial College London, Exhibition Road, SW72AZ London, United Kingdom
| | - James R. Durrant
- Department
of Chemistry, Centre for Processable Electronics, Imperial College London, White city campus, W12 0BZ London, United Kingdom
| | - Reshma R. Rao
- Department of
Materials, Imperial College London, Exhibition Road, SW72AZ London, United Kingdom
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4
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Kelly M, Yan B, Lucky C, Schreier M. Electrochemical Synthesis of Sound: Hearing the Electrochemical Double Layer. ACS Cent Sci 2024; 10:595-602. [PMID: 38559295 PMCID: PMC10979475 DOI: 10.1021/acscentsci.3c01253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 01/22/2024] [Accepted: 01/24/2024] [Indexed: 04/04/2024]
Abstract
Electrochemical double layers (EDLs) govern the operation of batteries, fuel cells, electrochemical sensors, and electrolyzers. However, their invisible nature makes their properties and function difficult to conceptualize, creating an impediment to the broader understanding of double-layer function required for future technologies in energy storage and chemical synthesis. To render the behavior of electrochemical interfaces more intuitive, we made the rearrangement of interfacial components audible by employing the EDL as a variable element in a relaxation oscillator circuit. Connecting the circuit to a speaker generated an audible output corresponding to the change in potential resulting from EDL rearrangement. Variations in the applied voltage, electrolyte concentration and identity, as well as in the electrode material, yielded audible frequency variations that provide an intuitive understanding of EDL behavior. We expect that hearing the trends in behavior will provide a helpful and alternative method for understanding molecular movement at the electrochemical interface.
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Affiliation(s)
- Megan Kelly
- Department
of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Bill Yan
- Department
of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Christine Lucky
- Department
of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
| | - Marcel Schreier
- Department
of Chemical and Biological Engineering, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
- Department
of Chemistry, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States
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5
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Pastor E, Lian Z, Xia L, Ecija D, Galán-Mascarós JR, Barja S, Giménez S, Arbiol J, López N, García de Arquer FP. Complementary probes for the electrochemical interface. Nat Rev Chem 2024; 8:159-178. [PMID: 38388837 DOI: 10.1038/s41570-024-00575-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/09/2024] [Indexed: 02/24/2024]
Abstract
The functions of electrochemical energy conversion and storage devices rely on the dynamic junction between a solid and a fluid: the electrochemical interface (EI). Many experimental techniques have been developed to probe the EI, but they provide only a partial picture. Building a full mechanistic understanding requires combining multiple probes, either successively or simultaneously. However, such combinations lead to important technical and theoretical challenges. In this Review, we focus on complementary optoelectronic probes and modelling to address the EI across different timescales and spatial scales - including mapping surface reconstruction, reactants and reaction modulators during operation. We discuss how combining these probes can facilitate a predictive design of the EI when closely integrated with theory.
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Affiliation(s)
- Ernest Pastor
- CNRS, IPR (Institut de Physique de Rennes), University of Rennes, Rennes, France.
- CNRS, Univ Rennes, DYNACOM (Dynamical Control of Materials Laboratory) - IRL2015, The University of Tokyo, Tokyo, Japan.
| | - Zan Lian
- ICIQ-Institute of Chemical Research of Catalonia, The Barcelona Institute of Science and Technology, Tarragona, Spain
| | - Lu Xia
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain
| | - David Ecija
- IMDEA Nanoscience, Campus Universitario de Cantoblanco, Madrid, Spain
| | - José Ramón Galán-Mascarós
- ICIQ-Institute of Chemical Research of Catalonia, The Barcelona Institute of Science and Technology, Tarragona, Spain
- ICREA, Barcelona, Spain
| | - Sara Barja
- Department of Polymers and Advanced Materials, Centro de Física de Materiales (CFM), University of the Basque Country UPV/EHU, San Sebastián, Spain
- Donostia International Physics Center (DIPC), San Sebastián, Spain
- IKERBASQUE, Basque Foundation for Science, Bilbao, Spain
| | - Sixto Giménez
- Institute of Advanced Materials (INAM) Universitat Jaume I, Castelló, Spain
| | - Jordi Arbiol
- ICREA, Barcelona, Spain
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and BIST, Campus UAB, Bellaterra, Barcelona, Catalonia, Spain
| | - Núria López
- ICIQ-Institute of Chemical Research of Catalonia, The Barcelona Institute of Science and Technology, Tarragona, Spain
| | - F Pelayo García de Arquer
- ICFO-Institut de Ciències Fotòniques, The Barcelona Institute of Science and Technology, Barcelona, Spain.
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6
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Xue S, Chaudhary P, Nouri MR, Gubanova E, Garlyyev B, Alexandrov V, Bandarenka AS. Impact of Pt( hkl) Electrode Surface Structure on the Electrical Double Layer Capacitance. J Am Chem Soc 2024; 146:3883-3889. [PMID: 38316015 DOI: 10.1021/jacs.3c11403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
The classical theory of the electrical double layer (EDL) does not consider the effects of the electrode surface structure on the EDL properties. Moreover, the best agreement between the traditional EDL theory and experiments has been achieved so far only for a very limited number of ideal systems, such as liquid metal mercury electrodes, for which it is challenging to operate with specific surface structures. In the case of solid electrodes, the predictive power of classical theory is often not acceptable for electrochemical energy applications, e.g., in supercapacitors, due to the effects of surface structure, electrode composition, and complex electrolyte contributions. In this work, we combine ab initio molecular dynamics (AIMD) simulations and electrochemical experiments to elucidate the relationship between the structure of Pt(hkl) surfaces and the double-layer capacitance as a key property of the EDL. Flat, stepped, and kinked Pt single crystal facets in contact with acidic HClO4 media are selected as our model systems. We demonstrate that introducing specific defects, such as steps, can substantially reduce the EDL capacitances close to the potential of zero charge (PZC). Our AIMD simulations reveal that different Pt facets are characterized by different net orientations of the water dipole moment at the interface. That allows us to rationalize the experimentally measured (inverse) volcano-shaped capacitance as a function of the surface step density.
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Affiliation(s)
- Song Xue
- Physics of Energy Conversion and Storage, Department of Physics, Technical University of Munich, James-Franck-Str. 1, 85748 Garching bei München, Germany
- Advanced Chemical Engineering and Energy Materials Research Center, China University of Petroleum (East China), Qingdao 266580, China
| | - Payal Chaudhary
- Department of Chemical and Biomolecular Engineering and Nebraska Center for Materials and Nanoscience, University of Nebraska─Lincoln, Lincoln, Nebraska 68588, United States
| | - Mohammad Reza Nouri
- Department of Chemical and Biomolecular Engineering and Nebraska Center for Materials and Nanoscience, University of Nebraska─Lincoln, Lincoln, Nebraska 68588, United States
| | - Elena Gubanova
- Physics of Energy Conversion and Storage, Department of Physics, Technical University of Munich, James-Franck-Str. 1, 85748 Garching bei München, Germany
| | - Batyr Garlyyev
- Physics of Energy Conversion and Storage, Department of Physics, Technical University of Munich, James-Franck-Str. 1, 85748 Garching bei München, Germany
| | - Vitaly Alexandrov
- Department of Chemical and Biomolecular Engineering and Nebraska Center for Materials and Nanoscience, University of Nebraska─Lincoln, Lincoln, Nebraska 68588, United States
| | - Aliaksandr S Bandarenka
- Physics of Energy Conversion and Storage, Department of Physics, Technical University of Munich, James-Franck-Str. 1, 85748 Garching bei München, Germany
- Catalysis Research Center, Technical University of Munich, Ernst-Otto-Fischer-Straße 1, 85748 Garching bei München, Germany
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7
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Limaye A, Suvlu D, Willard AP. Water molecules mute the dependence of the double-layer potential profile on ionic strength. Faraday Discuss 2024; 249:267-288. [PMID: 37830233 DOI: 10.1039/d3fd00114h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2023]
Abstract
We present the results of molecular dynamics simulations of a nanoscale electrochemical cell. The simulations include an aqueous electrolyte solution with varying ionic strength (i.e., concentrations ranging from 0-4 M) between a pair of metallic electrodes held at constant potential difference. We analyze these simulations by computing the electrostatic potential profile of the electric double-layer region and find it to be nearly independent of ionic concentration, in stark contrast to the predictions of standard continuum-based theories. We attribute this lack of concentration dependence to the molecular influences of water molecules at the electrode-solution interface. These influences include the molecular manifestation of water's dielectric response, which tends to drown out the comparatively weak screening requirement of the ions. To support our analysis, we decompose water's interfacial response into three primary contributions: molecular layering, intrinsic (zero-field) orientational polarization, and the dipolar dielectric response.
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Affiliation(s)
- Aditya Limaye
- Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
| | - Dylan Suvlu
- Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
| | - Adam P Willard
- Massachusetts Institute of Technology, Cambridge, Massachusetts, USA.
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8
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Xu Y, Zhang L, Chen W, Cui H, Cai J, Chen Y, Feliu JM, Herrero E. Boosting Oxygen Reduction at Pt(111)|Proton Exchange Ionomer Interfaces through Tuning the Microenvironment Water Activity. ACS Appl Mater Interfaces 2024; 16:4540-4549. [PMID: 38227931 DOI: 10.1021/acsami.3c14208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
A proton exchange ionomer is one of the most important components in membrane electrode assemblies (MEAs) of polymer electrolyte membrane fuel cells (PEMFCs). It acts as both a proton conductor and a binder for nanocatalysts and carbon supports. The structure and the wetting conditions of the MEAs have a great impact on the microenvironment at the three-phase interphases in the MEAs, which can significantly influence the electrode kinetics such as the oxygen reduction reaction (ORR) at the cathode. Herein, by using the Pt(111)|X ionomer interface as a model system (X = Nafion, Aciplex, D72), we find that higher drying temperature lowers the onset potential for sulfonate adsorption and reduces apparent ORR current, while the current wave for OHad formation drops and shifts positively. Surprisingly, the intrinsic ORR activity is higher after properly correcting the blocking effect of Pt active sites by sulfonate adsorption and the poly(tetrafluoroethylene) (PTFE) skeleton. These results are well explained by the reduced water activity at the interfaces induced by the ionomer/PTFE, according to the mixed potential effect. Implications for how to prepare MEAs with improved ORR activity are provided.
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Affiliation(s)
- Yujun Xu
- Hefei National Research Center for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Lulu Zhang
- Hefei National Research Center for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Wei Chen
- Hefei National Research Center for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Haowen Cui
- Hefei National Research Center for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Jun Cai
- Hefei National Research Center for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Yanxia Chen
- Hefei National Research Center for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China
| | - Juan M Feliu
- Instituto de Electroquímica, Universidad de Alicante, Apdo. 99, Alicante E-03080, Spain
| | - Enrique Herrero
- Instituto de Electroquímica, Universidad de Alicante, Apdo. 99, Alicante E-03080, Spain
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9
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Xu P, Wang R, Zhang H, Carnevale V, Borguet E, Suntivich J. Cation Modifies Interfacial Water Structures on Platinum during Alkaline Hydrogen Electrocatalysis. J Am Chem Soc 2024; 146:2426-2434. [PMID: 38228289 DOI: 10.1021/jacs.3c09128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2024]
Abstract
The molecular details of an electrocatalytic interface play an essential role in the production of sustainable fuels and value-added chemicals. Many electrochemical reactions exhibit strong cation-dependent activities, but how cations affect reaction kinetics is still elusive. We report the effect of cations (K+, Li+, and Ba2+) on the interfacial water structure using second-harmonic generation (SHG) and classical molecular dynamics (MD) simulation. The second- (χH2O(2)) and third-order (χH2O(3)) optical susceptibilities of water on Pt are smaller in the presence of Ba2+ compared to those of K+, suggesting that cations can affect the interfacial water orientation. MD simulation reproduces experimental SHG observations and further shows that the competition between cation hydration and interfacial water alignment governs the net water orientation. The impact of cations on interfacial water supports a cation hydration-mediated mechanism for hydrogen electrocatalysis; i.e., the reaction occurs via water dissociation followed by cation-assisted hydroxide/water exchange on Pt. Our study highlights the role of interfacial water in electrocatalysis and how innocent additives (such as cations) can affect the local electrochemical environment.
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Affiliation(s)
- Pengtao Xu
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14850, United States
| | - Ruiyu Wang
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, United States
- Center for Complex Materials from First-Principles (CCM), Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Haojian Zhang
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14850, United States
| | - Vincenzo Carnevale
- Institute for Computational Molecular Science, Temple University, Philadelphia, Pennsylvania 19122, United States
- Department of Biology, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Eric Borguet
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, United States
- Center for Complex Materials from First-Principles (CCM), Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Jin Suntivich
- Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14850, United States
- Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, New York 14850, United States
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10
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Liu BY, Zhen EF, Zhang LL, Cai J, Huang J, Chen YX. The pH-Induced Increase of the Rate Constant for HER at Au(111) in Acid Revealed by Combining Experiments and Kinetic Simulation. Anal Chem 2024; 96:67-75. [PMID: 38153001 DOI: 10.1021/acs.analchem.3c02818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
Origins of pH effects on the kinetics of electrocatalytic reactions involving the transfer of both protons and electrons, including the hydrogen evolution reaction (HER) considered in this study, are heatedly debated. By taking the HER at Au(111) in acid solutions of different pHs and ionic concentrations as the model systems, herein, we report how to derive the intrinsic kinetic parameters of such reactions and their pH dependence through the measurement of j-E curves and the corresponding kinetic simulation based on the Frumkin-Butler-Volmer theory and the modified Poisson-Nernst-Planck equation. Our study reveals the following: (i) the same set of kinetic parameters, such as the standard activation Gibbs free energy, charge transfer coefficient, and Gibbs adsorption energy for Had at Au(111), can simulate well all the j-E curves measured in solutions with different pH and temperatures; (ii) on the reversible hydrogen electrode scale, the intrinsic rate constant increases with the increase of pH, which is in contrast with the decrease of the HER current with the increase of pH; and (iii) the ratio of the rate constants for HER at Au(111) in x M HClO4 + (0.1 - x) M NaClO4 (pH ≤ 3) deduced before properly correcting the electric double layer (EDL) effects to the ones estimated with EDL correction is in the range of ca. 10 to 40, and even in a solution of x M HClO4 + (1 - x) M NaClO4 (pH ≤ 2) there is a difference of ca. 5× in the rate constants without and with EDL correction. The importance of proper correction of the EDL effects as well as several other important factors on unveiling the intrinsic pH-dependent reaction kinetics are discussed to help converge our analysis of pH effects in electrocatalysis.
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Affiliation(s)
- Bing-Yu Liu
- Hefei National Research Center for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Er-Fei Zhen
- Hefei National Research Center for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Lu-Lu Zhang
- Hefei National Research Center for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jun Cai
- Hefei National Research Center for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jun Huang
- Institute of Energy and Climate Research, IEK-13: Theory and Computation of Energy Materials, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
- Theorie Elektrokatalytischer Grenzflächen, Fakultät für Georessourcen und Materialtechnik, RWTH Aachen University, 52062 Aachen, Germany
| | - Yan-Xia Chen
- Hefei National Research Center for Physical Sciences at Microscale, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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11
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Kim M, Batsa Tetteh E, Krysiak OA, Savan A, Xiao B, Piotrowiak TH, Andronescu C, Ludwig A, Dong Chung T, Schuhmann W. Acidic Hydrogen Evolution Electrocatalysis at High-Entropy Alloys Correlates with its Composition-Dependent Potential of Zero Charge. Angew Chem Int Ed Engl 2023; 62:e202310069. [PMID: 37537136 DOI: 10.1002/anie.202310069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 07/30/2023] [Accepted: 08/02/2023] [Indexed: 08/05/2023]
Abstract
The vast possibilities in the elemental combinations of high-entropy alloys (HEAs) make it essential to discover activity descriptors for establishing rational electrocatalyst design principles. Despite the increasing attention on the potential of zero charge (PZC) of hydrogen evolution reaction (HER) electrocatalyst, neither the PZC of HEAs nor the impact of the PZC on the HER activity at HEAs has been described. Here, we use scanning electrochemical cell microscopy (SECCM) to determine the PZC and the HER activities of various elemental compositions of a Pt-Pd-Ru-Ir-Ag thin-film HEA materials library (HEA-ML) with high statistical reliability. Interestingly, the PZC of Pt-Pd-Ru-Ir-Ag is linearly correlated with its composition-weighted average work function. The HER current density in acidic media positively correlates with the PZC, which can be explained by the preconcentration of H+ in the electrical double layer at potentials negative of the PZC.
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Affiliation(s)
- Moonjoo Kim
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
| | - Emmanuel Batsa Tetteh
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
| | - Olga A Krysiak
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
| | - Alan Savan
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum Universitätsstr. 150, D-44780, Bochum, Germany
| | - Bin Xiao
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum Universitätsstr. 150, D-44780, Bochum, Germany
| | - Tobias Horst Piotrowiak
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum Universitätsstr. 150, D-44780, Bochum, Germany
| | - Corina Andronescu
- Technical Chemistry III and CENIDE Center for Nanointegration, Faculty of Chemistry, University of Duisburg-Essen, Carl-Benz-Straße 199, D-45141, Duisburg, Germany
| | - Alfred Ludwig
- Chair for Materials Discovery and Interfaces, Institute for Materials, Faculty of Mechanical Engineering, Ruhr University Bochum Universitätsstr. 150, D-44780, Bochum, Germany
- ZGH, Ruhr, University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
| | - Taek Dong Chung
- Department of Chemistry, Seoul National University, Seoul, 08826, Republic of Korea
- Advanced Institute of Convergence Technology, Suwon-si, Gyeonggi-do 16229, Republic of Korea
| | - Wolfgang Schuhmann
- Analytical Chemistry-Center for Electrochemical Sciences (CES), Faculty of Chemistry and Biochemistry, Ruhr University Bochum, Universitätsstr. 150, D-44780, Bochum, Germany
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12
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Seal A, Tiwari U, Gupta A, Govind Rajan A. Incorporating ion-specific van der Waals and soft repulsive interactions in the Poisson-Boltzmann theory of electrical double layers. Phys Chem Chem Phys 2023; 25:21708-21722. [PMID: 37551893 DOI: 10.1039/d3cp00745f] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/09/2023]
Abstract
Electrical double layers (EDLs) arise when an electrolyte is in contact with a charged surface, and are encountered in several application areas including batteries, supercapacitors, electrocatalytic reactors, and colloids. Over the last century, the development of Poisson-Boltzmann (PB) models and their modified versions have provided significant physical insight into the structure and dynamics of the EDL. Incorporation of physics such as finite-ion-size effects, dielectric decrement, and ion-ion correlations has made such models increasingly accurate when compared to more computationally expensive approaches such as molecular simulations and classical density functional theory. However, a prominent knowledge gap has been the exclusion of van der Waals (vdW) and soft repulsive interactions in modified PB models. Although short-ranged as compared to electrostatic interactions, we show here that vdW and soft repulsive interactions can play an important role in determining the structure of the EDL via the formation of a Stern layer and in modulating the differential capacitance of an electrode in an electrolyte. To this end, we incorporate ion-ion and wall-ion vdW attraction and soft repulsion via a 12-6 Lennard-Jones (LJ) potential, resulting in a modified PB-LJ approach. The wall-ion LJ interactions were found to have a significant effect on the electrical potential and concentration profiles, especially close to the wall. However, ion-ion LJ interactions do not affect the EDL structure at low bulk ion concentrations (<1 M). We also derive dimensionless numbers to quantify the impact of ion-ion and wall-ion LJ interactions on the EDL. Furthermore, in the pursuit of capturing ion-specific effects, we apply our model by considering various ions such as Na, K+, Mg2+, Cl-, and SO42-. We observe how varying parameters such as the electrolyte concentration and electrode potential affect the structure of the EDL due to the competition between ion-specific LJ and electrostatic interactions. Lastly, we show that the inclusion of vdW and soft repulsion interactions, as well as hydration effects, leads to a better qualitative agreement of the PB models with experimental double-layer differential capacitance data. Overall, the modified PB-LJ approach presented herein will lead to more accurate theoretical descriptions of EDLs in various application areas.
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Affiliation(s)
- Aniruddha Seal
- School of Chemical Sciences, National Institute of Science Education and Research Bhubaneswar, Homi Bhabha National Institute, Khurda, Odisha 752050, India
- Department of Chemical Engineering, Indian Institute of Science, Bengaluru, Karnataka 560012, India.
| | - Utkarsh Tiwari
- Department of Chemical Engineering, Birla Institute of Technology and Science Pilani, K K Birla Goa Campus, Zuarinagar, Goa 403726, India
- Department of Chemical Engineering, Indian Institute of Science, Bengaluru, Karnataka 560012, India.
| | - Ankur Gupta
- Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80309, USA
| | - Ananth Govind Rajan
- Department of Chemical Engineering, Indian Institute of Science, Bengaluru, Karnataka 560012, India.
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13
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Ringe S. The importance of a charge transfer descriptor for screening potential CO 2 reduction electrocatalysts. Nat Commun 2023; 14:2598. [PMID: 37147278 PMCID: PMC10162986 DOI: 10.1038/s41467-023-37929-4] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 03/30/2023] [Indexed: 05/07/2023] Open
Abstract
It has been over twenty years since the linear scaling of reaction intermediate adsorption energies started to coin the fields of heterogeneous and electrocatalysis as a blessing and a curse at the same time. It has established the possibility to construct activity volcano plots as a function of a single or two readily accessible adsorption energies as descriptors, but also limited the maximal catalytic conversion rate. In this work, it is found that these established adsorption energy-based descriptor spaces are not applicable to electrochemistry, because they are lacking an important additional dimension, the potential of zero charge. This extra dimension arises from the interaction of the electric double layer with reaction intermediates which does not scale with adsorption energies. At the example of the electrochemical reduction of CO2 it is shown that the addition of this descriptor breaks the scaling relations, opening up a huge chemical space that is readily accessible via potential of zero charge-based material design. The potential of zero charge also explains product selectivity trends of electrochemical CO2 reduction in close agreement with reported experimental data highlighting its importance for electrocatalyst design.
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Affiliation(s)
- Stefan Ringe
- Department of Chemistry, Korea University, Seoul, 02841, Republic of Korea.
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14
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Rossmeisl J. Measuring the potential of zero charge. Nat Mater 2023; 22:419-420. [PMID: 37002502 DOI: 10.1038/s41563-023-01505-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Affiliation(s)
- Jan Rossmeisl
- Department of Chemistry, University of Copenhagen, Copenhagen, Denmark.
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15
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Huang J, Marshall CR, Ojha K, Shen M, Golledge S, Kadota K, McKenzie J, Fabrizio K, Mitchell JB, Khaliq F, Davenport AM, LeRoy MA, Mapile AN, Debela TT, Twight LP, Hendon CH, Brozek CK. Giant Redox Entropy in the Intercalation vs Surface Chemistry of Nanocrystal Frameworks with Confined Pores. J Am Chem Soc 2023; 145:6257-6269. [PMID: 36893341 DOI: 10.1021/jacs.2c12846] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/11/2023]
Abstract
Redox intercalation involves coupled ion-electron motion within host materials, finding extensive application in energy storage, electrocatalysis, sensing, and optoelectronics. Monodisperse MOF nanocrystals, compared to their bulk phases, exhibit accelerated mass transport kinetics that promote redox intercalation inside nanoconfined pores. However, nanosizing MOFs significantly increases their external surface-to-volume ratios, making the intercalation redox chemistry into MOF nanocrystals difficult to understand due to the challenge of differentiating redox sites at the exterior of MOF particles from the internal nanoconfined pores. Here, we report that Fe(1,2,3-triazolate)2 possesses an intercalation-based redox process shifted ca. 1.2 V from redox at the particle surface. Such distinct chemical environments do not appear in idealized MOF crystal structures but become magnified in MOF nanoparticles. Quartz crystal microbalance and time-of-flight secondary ion mass spectrometry combined with electrochemical studies identify the existence of a distinct and highly reversible Fe2+/Fe3+ redox event occurring within the MOF interior. Systematic manipulation of experimental parameters (e.g., film thickness, electrolyte species, solvent, and reaction temperature) reveals that this feature arises from the nanoconfined (4.54 Å) pores gating the entry of charge-compensating anions. Due to the requirement for full desolvation and reorganization of electrolyte outside the MOF particle, the anion-coupled oxidation of internal Fe2+ sites involves a giant redox entropy change (i.e., 164 J K-1 mol-1). Taken together, this study establishes a microscopic picture of ion-intercalation redox chemistry in nanoconfined environments and demonstrates the synthetic possibility of tuning electrode potentials by over a volt, with profound implications for energy capture and storage technologies.
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Affiliation(s)
- Jiawei Huang
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Checkers R Marshall
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Kasinath Ojha
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Meikun Shen
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Stephen Golledge
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Kentaro Kadota
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Jacob McKenzie
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Kevin Fabrizio
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - James B Mitchell
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Faiqa Khaliq
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Audrey M Davenport
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Michael A LeRoy
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Ashley N Mapile
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Tekalign T Debela
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Liam P Twight
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Christopher H Hendon
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
| | - Carl K Brozek
- Department of Chemistry and Biochemistry, Material Science Institute, University of Oregon, Eugene, Oregon 97403, United States
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16
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Yeasmin S, Ullah A, Wu B, Zhang X, Cheng LJ. Enzyme-Mimics for Sensitive and Selective Steroid Metabolite Detection. ACS Appl Mater Interfaces 2023. [PMID: 36908226 DOI: 10.1021/acsami.2c21980] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
We present an enzyme-like functional polymer that recognizes nonelectroactive targets and catalyzes their redox reactions for simple, selective steroid metabolite detection. Measuring steroid metabolites, such as cortisol, has been widely adopted to diagnose stress and chronic diseases. Conventional detection method based on competitive immunoassay requires time-consuming labeling processes for signal transduction and unstable biological receptors for biorecognition yet with limited selectivity. Inspired by natural enzymes' target specificity and catalytic nature, we report an enzyme-mimic using electrocatalytic molecularly imprinted polymers (EC-MIP) to achieve label-free, external redox reagent-free, sensitive, and selective electrochemical detection of cortisol. The EC-MIP sensor contains molecularly imprinted cavities for specific cortisol binding and embedded copper phthalocyanine tetrasulfonate (CuPcTS) for electrocatalytic reduction of the ketones on the captured cortisol into alcohols. The direct sensing approach resolves the intrinsic limitations of conventional MIP-based sensors, most notably the use of external redox probes and weak sensing signals. The sensor exhibited a detection limit of 181 pM with significantly enhanced selectivity using a differential sensing mechanism. The new enzyme-like sensor can be modified to detect other targets, offering a simple, robust approach to future health monitoring technologies.
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Affiliation(s)
- Sanjida Yeasmin
- School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97331, United States
| | - Ahasan Ullah
- School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97331, United States
| | - Bo Wu
- School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97331, United States
| | - Xueqiao Zhang
- School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97331, United States
| | - Li-Jing Cheng
- School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97331, United States
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17
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Li XY, Jin XF, Yang XH, Wang X, Le JB, Cheng J. Molecular understanding of the Helmholtz capacitance difference between Cu(100) and graphene electrodes. J Chem Phys 2023; 158:084701. [PMID: 36859091 DOI: 10.1063/5.0139534] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Unraveling the origin of Helmholtz capacitance is of paramount importance for understanding the interfacial structure and electrostatic potential distribution of electric double layers (EDL). In this work, we combined the methods of ab initio molecular dynamics and classical molecular dynamics and modeled electrified Cu(100)/electrolyte and graphene/electrolyte interfaces for comparison. It was proposed that the Helmholtz capacitance is composed of three parts connected in series: the usual solvent capacitance, water chemisorption induced capacitance, and Pauling repulsion caused gap capacitance. We found the Helmholtz capacitance of graphene is significantly lower than that of Cu(100), which was attributed to two intrinsic factors. One is that graphene has a wider gap layer at interface, and the other is that graphene is less active for water chemisorption. Finally, based on our findings, we provide suggestions for how to increase the EDL capacitance of graphene-based materials in future work, and we also suggest that the new understanding of the potential distribution across the Helmholtz layer may help explain some experimental phenomena of electrocatalysis.
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Affiliation(s)
- Xiang-Ying Li
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Xiang-Feng Jin
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Xiao-Hui Yang
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
| | - Xue Wang
- Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
| | - Jia-Bo Le
- Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China
| | - Jun Cheng
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China
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18
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Huang J. Zooming into the Inner Helmholtz Plane of Pt(111)-Aqueous Solution Interfaces: Chemisorbed Water and Partially Charged Ions. JACS Au 2023; 3:550-564. [PMID: 36873696 PMCID: PMC9975841 DOI: 10.1021/jacsau.2c00650] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2022] [Revised: 01/13/2023] [Accepted: 01/13/2023] [Indexed: 06/18/2023]
Abstract
The double layer on transition metals, i.e., platinum, features chemical metal-solvent interactions and partially charged chemisorbed ions. Chemically adsorbed solvent molecules and ions are situated closer to the metal surface than electrostatically adsorbed ions. This effect is described tersely by the concept of an inner Helmholtz plane (IHP) in classical double layer models. The IHP concept is extended here in three aspects. First, a refined statistical treatment of solvent (water) molecules considers a continuous spectrum of orientational polarizable states, rather than a few representative states, and non-electrostatic, chemical metal-solvent interactions. Second, chemisorbed ions are partially charged, rather than being electroneutral or having integral charges as in the solution bulk, with the coverage determined by a generalized, energetically distributed adsorption isotherm. The surface dipole moment induced by partially charged, chemisorbed ions is considered. Third, considering different locations and properties of chemisorbed ions and solvent molecules, the IHP is divided into two planes, namely, an AIP (adsorbed ion plane) and ASP (adsorbed solvent plane). The model is used to study how the partially charged AIP and polarizable ASP lead to intriguing double-layer capacitance curves that are different from what the conventional Gouy-Chapman-Stern model describes. The model provides an alternative interpretation for recent capacitance data of Pt(111)-aqueous solution interfaces calculated from cyclic voltammetry. This revisit brings forth questions regarding the existence of a pure double-layer region at realistic Pt(111). The implications, limitations, and possible experimental confirmation of the present model are discussed.
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19
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Binninger T. First-principles theory of electrochemical capacitance. Electrochim Acta 2023. [DOI: 10.1016/j.electacta.2023.142016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
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20
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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: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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21
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Chen A, Le JB, Kuang Y, Cheng J. Modeling stepped Pt/water interfaces at potential of zero charge with ab initio molecular dynamics. J Chem Phys 2022; 157:094702. [DOI: 10.1063/5.0100678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
It is worthwhile to understand the potentials of zero charge (PZCs) and structures of stepped metal/water interfaces, because for many electrocatalytic reactions stepped surfaces are more active than atomically flat surfaces. Herein, a series of stepped Pt/water interfaces are modeled at different step densities with ab initio molecular dynamics (AIMD). It is found that the structures of Pt/water interfaces are significantly influenced by the step density, particularly for the distribution of chemisorbed water. The step sites of metal surfaces are more preferred for water chemisorption than the terrace sites, and until the step density is very low, water will chemisorb on the terrace. In addition, it is revealed that the PZCs of stepped Pt/water interfaces are generally smaller than that of Pt(111), and the difference is mainly attributed to the difference in the work function, providing a simple way to estimate the PZCs of stepped metal surfaces. Finally, it is interesting to see that the Volta potential difference is almost same for Pt/water interfaces with different step densities, although their interface structures and magnitude of charge transfer clearly differ.
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Affiliation(s)
| | - Jia-Bo Le
- Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, China
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22
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Kuznetcov I, Kantzas A, Bryant S. Dielectric spectroscopy of nanofluids in deionized water: Method of removing electrode polarization effect. Colloids Surf A Physicochem Eng Asp 2022. [DOI: 10.1016/j.colsurfa.2022.129039] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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23
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Guha A, Sahoo M, Alam K, Rao DK, Sen P, Narayanan TN. Role of Water Structure in Alkaline Water Electrolysis. iScience 2022; 25:104835. [PMID: 35992077 PMCID: PMC9389238 DOI: 10.1016/j.isci.2022.104835] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2022] [Revised: 06/29/2022] [Accepted: 07/20/2022] [Indexed: 11/02/2022] Open
Abstract
Herein, with the help of experimental and first-principles density functional theory (DFT)-based studies, we have shown that structural changes in the water coordination in electrolytes having high alkalinity can be a possible reason for the reduced catalytic activity of platinum (Pt) in high pH. Studies with polycrystalline Pt electrodes indicate that electrocatalytic HER activity reduces in terms of high overpotential required, high Tafel slope, and high charge transfer resistances in concentrated aqueous alkaline electrolytes (say 6 M KOH) in comparison to that in low alkaline electrolytes (say 0.1 M KOH), irrespective of the counter cations (Na+, K+, or Rb+) present. The changes in the water structure of bulk electrolytes as well as that in electrode-electrolyte interface are studied. The results are compared with DFT-based analysis, and the study can pave new directions in studying the HER process in terms of the water structure near the electrode-electrolyte interface. A mechanistic insight into the alkaline hydrogen evolution reaction (HER) is provided The role of water structure/coordination variation in HER kinetics is studied The interfacial water structure variation is studied using in situ Raman studies The Pt−H coverage changes during the HER process are also investigated
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24
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Huang J, Zhang Y. Essays on Conceptual Electrochemistry: I. Bridging Open-Circuit Voltage of Electrochemical Cells and Charge Distribution at Electrode–Electrolyte Interfaces. Front Chem 2022; 10:938064. [PMID: 35958239 PMCID: PMC9358007 DOI: 10.3389/fchem.2022.938064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 06/21/2022] [Indexed: 11/13/2022] Open
Abstract
We ponder over how an electrochemical cell conforms itself to the open-circuit voltage (OCV) given by the Nernst equation, where properties of the electrodes play no role. We first show, via a pedagogical derivation of the Nernst equation, how electrode properties are canceled and then take a closer look into the electrode–electrolyte interface at one electrode by linking charge and potential distributions. We obtain an equilibrium Poisson–Nernst equation that shows how the charge distribution across an electrode–electrolyte interface can be dictated by the chemical potentials of redox species. Taking a H2/O2 fuel cell as an example, we demystify the formal analysis by showing how the two electrodes delicately regulate their “electron tails” to abide by the Nernst equation. In this example, we run into a seemingly counterintuitive phenomenon that two electrodes made of the same transition metal display two distinct potentials of zero charge. This example indicates that the double layer at transition metals with chemisorption can display distinct behaviors compared to ideally polarizable double layers at sp metals.
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25
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Yang S, Zhao X, Lu YH, Barnard ES, Yang P, Baskin A, Lawson JW, Prendergast D, Salmeron M. Nature of the Electrical Double Layer on Suspended Graphene Electrodes. J Am Chem Soc 2022; 144:13327-13333. [PMID: 35849827 PMCID: PMC9335527 DOI: 10.1021/jacs.2c03344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022]
Abstract
![]()
The structure of interfacial water near suspended graphene
electrodes
in contact with aqueous solutions of Na2SO4,
NH4Cl, and (NH4)2SO4 has
been studied using confocal Raman spectroscopy, sum frequency vibrational
spectroscopy, and Kelvin probe force microscopy. SO42– anions were found to preferentially accumulate near
the interface at an open circuit potential (OCP), creating an electrical
field that orients water molecules below the interface, as revealed
by the increased intensity of the O–H stretching peak of H-bonded
water. No such increase is observed with NH4Cl at the OCP.
The intensity of the dangling O–H bond stretching peak however
remains largely unchanged. The degree of orientation of the water
molecules as well as the electrical double layer strength increased
further when positive voltages are applied. Negative voltages on the
other hand produced only small changes in the intensity of the H-bonded
water peaks but affected the intensity and frequency of dangling O–H
bond peaks. The TOC figure is an oversimplified representation of
the system in this work.
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Affiliation(s)
- Shanshan Yang
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Xiao Zhao
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.,Department of Materials Science and Engineering, University of California, Berkeley, California 94720, United States
| | - Yi-Hsien Lu
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Edward S Barnard
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Peidong Yang
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.,Department of Chemistry, University of California-Berkeley, Berkeley, California 94720, United States
| | - Artem Baskin
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.,NASA Ames Research Center, Moffett Field, California 94035, United States
| | - John W Lawson
- NASA Ames Research Center, Moffett Field, California 94035, United States
| | - David Prendergast
- Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Miquel Salmeron
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States.,Department of Materials Science and Engineering, University of California, Berkeley, California 94720, United States
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26
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Rahpeima S, Le Brun A, Raston CL, Darwish N. Electro-polymerization rates of diazonium salts are dependent on the crystal orientation of the surface. J Colloid Interface Sci 2022; 626:985-94. [PMID: 35839679 DOI: 10.1016/j.jcis.2022.07.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 06/30/2022] [Accepted: 07/03/2022] [Indexed: 02/05/2023]
Abstract
Electro-polymerization of diazonium salts is widely used for modifying surfaces with thin organic films. Initially this method was primarily applied to carbon, then to metals, and more recently to semiconducting Si. Unlike on other surfaces, electrochemical reduction of diazonium salts on Si, which is one of the most industrially dominant material, is not well understood. Here, we report the electrochemical reduction of diazonium salts on a range of silicon electrodes of different crystal orientations (111, 211, 311, 411, and 100). We show that the kinetics of surface reaction and the reduction potential is Si crystal-facet dependent and is more favorable in the hierarchical order (111) > (211) > (311) > (411) > (100), a finding that offers control over the surface chemistry of diazonium salts on Si. The dependence of the surface reaction kinetics on the crystal orientation was found to be directly related to differences in the potential of zero charge (PZC) of each crystal orientation, which in turn controls the adsorption of the diazonium cations prior to reduction. Another consequence of the effect of PZC on the adsorption of diazonium cations, is that molecules terminated by distal diazonium moieties form a compact film in less time and requires less reduction potentials compared to that formed from diazonium molecules terminated by only one diazo moiety. In addition, at higher concentrations of diazonium cations, the mechanism of electrochemical polymerization on the surface becomes PZC-controlled adsorption-dominated inner-sphere electron transfer while at lower concentrations, diffusion-based outer-sphere electron transfer dominates. These findings help understanding the electro-polymerization reaction of diazonium salts on Si en route towards an integrated molecular and Si electronics technology.
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Ovalle VJ, Hsu YS, Agrawal N, Janik MJ, Waegele MM. Correlating hydration free energy and specific adsorption of alkali metal cations during CO2 electroreduction on Au. Nat Catal 2022. [DOI: 10.1038/s41929-022-00816-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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28
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Abstract
Significant progress has been made in recent years in theoretical modeling of the electric double layer (EDL), a key concept in electrochemistry important for energy storage, electrocatalysis, and multitudes of other technological applications. However, major challenges remain in understanding the microscopic details of the electrochemical interface and charging mechanisms under realistic conditions. This review delves into theoretical methods to describe the equilibrium and dynamic responses of the EDL structure and capacitance for electrochemical systems commonly deployed for capacitive energy storage. Special emphasis is given to recent advances that intend to capture the nonclassical EDL behavior such as oscillatory ion distributions, polarization of nonmetallic electrodes, charge transfer, and various forms of phase transitions in the micropores of electrodes interfacing with an organic electrolyte or ionic liquid. This comprehensive analysis highlights theoretical insights into predictable relationships between materials characteristics and electrochemical performance and offers a perspective on opportunities for further development toward rational design and optimization of electrochemical systems.
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Affiliation(s)
- Jianzhong Wu
- Department of Chemical and Environmental Engineering, University of California, Riverside, California 92521, United States
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