1
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Iqbal A, Skulason E, Abghoui Y. Electrochemical Nitrogen Reduction to Ammonia at Ambient Condition on the (111) Facets of Transition Metal Carbonitrides. Chemphyschem 2024:e202300991. [PMID: 38568155 DOI: 10.1002/cphc.202300991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 03/21/2024] [Indexed: 05/15/2024]
Abstract
We conducted Density Functional Theory calculations to investigate a class of materials with the goal of enabling nitrogen activation and electrochemical ammonia production under ambient conditions. The source of protons at the anode could originate from either water splitting or H2, but our specific focus was on the cathode reaction, where nitrogen is reduced into ammonia. We examined the conventional associative mechanism, dissociative mechanism, and Mars-van Krevelen mechanism on the (111) facets of the NaCl-type structure found in early transition metal carbonitrides, including Ti, V, Cr, Zr, Nb, Mo, Hf, Ta, Sc, Y, and W. We explored the catalytic activity by calculating the free energy of all intermediates along the reaction pathway and constructing free energy diagrams to identify the steps that determine the reaction's feasibility. Additionally, we closely examined the potential for catalyst poisoning within the electrochemical environment, considering the bias required to drive the reaction. Furthermore, we assessed the likelihood of catalyst decomposition and the potential for catalyst regeneration among the most intriguing carbonitrides. Our findings revealed that the only carbonitride catalyst considered here exhibiting both activity and stability, capable of self-regeneration and nitrogen-to-ammonia activation, is NbCN with a low potential-determining step energy of 0.58 eV. This material can facilitate ammonia formation via a mixed associative-MvK mechanism. In contrast, other carbonitrides of this crystallographic orientation are likely to undergo decomposition, reverting to their parent metals under operational conditions.
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Affiliation(s)
- Atef Iqbal
- Science Institute of the University of Iceland
| | - Egill Skulason
- Faculty of Industrial Engineering, Mechanical Engineering and Computer Science, University of Iceland
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2
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Elnagar MM, Menezes PV, Parada WA, Mattausch Y, Kibler LA, Mayrhofer KJJ, Jacob T. Tailoring Cu Electrodes for Enhanced CO 2 Electroreduction through Plasma Electrolysis in Non-Conventional Phosphorus-Oxoanion-Based Electrolytes. CHEMSUSCHEM 2023:e202300934. [PMID: 37544913 DOI: 10.1002/cssc.202300934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 08/01/2023] [Accepted: 08/04/2023] [Indexed: 08/08/2023]
Abstract
This study presents a green, ultra-fast, and facile technique for the fabrication of micro/nano-structured and porous Cu electrodes through in-liquid plasma electrolysis using phosphorous-oxoanion-based electrolytes. Besides the preferential surface faceting, the Cu electrodes exhibit unique surface structures, including octahedral nanocrystals besides nanoporous and microporous structures, depending on the employed electrolyte. The incorporation of P-atoms into the Cu surfaces is observed. The modified Cu electrodes display increased roughness, leading to higher current densities for CO2 electroreduction reaction. The selectivity of the modified Cu electrodes towards C2 products is highest for the Cu electrodes treated in Na2 HPO3 and Na3 PO4 electrolytes, whereas those treated in Na2 H2 PO2 produce the most H2 . The Cu electrode treated in Na3 PO4 produces ethylene (23 %) at -1.1 V vs. RHE, and a comparable amount of acetaldehyde (15 %) that is typically observed for Cu(110) single crystals. The enhanced selectivity is attributed to several factors, including the surface morphology, the incorporation of phosphorus into the Cu structure, and the formation of Cu(110) facets. Our results not only advance our understanding of the influence of the electrolyte's nature on the plasma electrolysis of Cu electrodes, but also underscores the potential of in-liquid plasma treatment for developing efficient Cu electrocatalysts for sustainable CO2 conversion.
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Affiliation(s)
| | - Pramod V Menezes
- Institute of Electrochemistry, Ulm University, 89069, Ulm, Germany
| | - Walter A Parada
- Helmholtz Institute Erlangen-Nürnberg for Renewable Energy (HI ERN), Egerlandstr. 3, 91058, Erlangen, Germany
| | | | - Ludwig A Kibler
- Institute of Electrochemistry, Ulm University, 89069, Ulm, Germany
| | - Karl J J Mayrhofer
- Helmholtz Institute Erlangen-Nürnberg for Renewable Energy (HI ERN), Egerlandstr. 3, 91058, Erlangen, Germany
| | - Timo Jacob
- Institute of Electrochemistry, Ulm University, 89069, Ulm, Germany
- Helmholtz-Institute-Ulm (HIU) Electrochemical Energy Storage, 89081, Ulm, Germany
- Karlsruhe Institute of Technology (KIT), P.O. Box 3640, 76021, Karlsruhe, Germany
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3
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Gianolio D, Higham MD, Quesne MG, Aramini M, Xu R, Large AI, Held G, Velasco-Vélez JJ, Haevecker M, Knop-Gericke A, Genovese C, Ampelli C, Schuster ME, Perathoner S, Centi G, Catlow CRA, Arrigo R. Interfacial Chemistry in the Electrocatalytic Hydrogenation of CO 2 over C-Supported Cu-Based Systems. ACS Catal 2023; 13:5876-5895. [PMID: 37180964 PMCID: PMC10167656 DOI: 10.1021/acscatal.3c01288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 03/31/2023] [Indexed: 05/16/2023]
Abstract
Operando soft and hard X-ray spectroscopic techniques were used in combination with plane-wave density functional theory (DFT) simulations to rationalize the enhanced activities of Zn-containing Cu nanostructured electrocatalysts in the electrocatalytic CO2 hydrogenation reaction. We show that at a potential for CO2 hydrogenation, Zn is alloyed with Cu in the bulk of the nanoparticles with no metallic Zn segregated; at the interface, low reducible Cu(I)-O species are consumed. Additional spectroscopic features are observed, which are identified as various surface Cu(I) ligated species; these respond to the potential, revealing characteristic interfacial dynamics. Similar behavior was observed for the Fe-Cu system in its active state, confirming the general validity of this mechanism; however, the performance of this system deteriorates after successive applied cathodic potentials, as the hydrogen evolution reaction then becomes the main reaction pathway. In contrast to an active system, Cu(I)-O is now consumed at cathodic potentials and not reversibly reformed when the voltage is allowed to equilibrate at the open-circuit voltage; rather, only the oxidation to Cu(II) is observed. We show that the Cu-Zn system represents the optimal active ensembles with stabilized Cu(I)-O; DFT simulations rationalize this observation by indicating that Cu-Zn-O neighboring atoms are able to activate CO2, whereas Cu-Cu sites provide the supply of H atoms for the hydrogenation reaction. Our results demonstrate an electronic effect exerted by the heterometal, which depends on its intimate distribution within the Cu phase and confirms the general validity of these mechanistic insights for future electrocatalyst design strategies.
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Affiliation(s)
- Diego Gianolio
- Diamond
Light Source Ltd., Harwell
Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, U.K.
| | - Michael D. Higham
- Cardiff
Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, Wales CF10 3AT, U.K.
- UK Catalysis
Hub, Research Complex at Harwell, Rutherford
Appleton Laboratory, R92, Harwell, Oxfordshire OX11 0FA, U.K.
- Department
of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K.
| | - Matthew G. Quesne
- Cardiff
Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, Wales CF10 3AT, U.K.
- UK Catalysis
Hub, Research Complex at Harwell, Rutherford
Appleton Laboratory, R92, Harwell, Oxfordshire OX11 0FA, U.K.
| | - Matteo Aramini
- Diamond
Light Source Ltd., Harwell
Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, U.K.
| | - Ruoyu Xu
- Department
of Chemical Engineering, University College
London, 20 Gordon Street, London WC1H 0AJ, U.K.
| | - Alex I. Large
- Diamond
Light Source Ltd., Harwell
Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, U.K.
| | - Georg Held
- Diamond
Light Source Ltd., Harwell
Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, U.K.
| | - Juan-Jesús Velasco-Vélez
- Max-Planck-Institut
für Chemische Energiekonversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
- Department
of Inorganic Chemistry, Fritz-Haber-Institut
der Max-Planck Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Michael Haevecker
- Max-Planck-Institut
für Chemische Energiekonversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
- Department
of Inorganic Chemistry, Fritz-Haber-Institut
der Max-Planck Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Axel Knop-Gericke
- Max-Planck-Institut
für Chemische Energiekonversion, Stiftstrasse 34-36, 45470 Mülheim an der Ruhr, Germany
- Department
of Inorganic Chemistry, Fritz-Haber-Institut
der Max-Planck Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Chiara Genovese
- Department
of ChiBioFarAm, ERIC aisbl and CASPE/INSTM, University of Messina, V. le F.Stagno D’ Alcontres 31, 98166 Messina, Italy
| | - Claudio Ampelli
- Department
of ChiBioFarAm, ERIC aisbl and CASPE/INSTM, University of Messina, V. le F.Stagno D’ Alcontres 31, 98166 Messina, Italy
| | | | - Siglinda Perathoner
- Department
of ChiBioFarAm, ERIC aisbl and CASPE/INSTM, University of Messina, V. le F.Stagno D’ Alcontres 31, 98166 Messina, Italy
| | - Gabriele Centi
- Department
of ChiBioFarAm, ERIC aisbl and CASPE/INSTM, University of Messina, V. le F.Stagno D’ Alcontres 31, 98166 Messina, Italy
| | - C. Richard A. Catlow
- Diamond
Light Source Ltd., Harwell
Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, U.K.
- Cardiff
Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, Cardiff, Wales CF10 3AT, U.K.
- UK Catalysis
Hub, Research Complex at Harwell, Rutherford
Appleton Laboratory, R92, Harwell, Oxfordshire OX11 0FA, U.K.
- Department
of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, U.K.
| | - Rosa Arrigo
- Diamond
Light Source Ltd., Harwell
Science & Innovation Campus, Didcot, Oxfordshire OX11 0DE, U.K.
- School
of Science, Engineering and Environment, University of Salford, Cockcroft Building, Salford, Greater Manchester M5 4WT, U.K.
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4
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Shao F, Xia Z, You F, Wong JK, Low QH, Xiao H, Yeo BS. Surface Water as an Initial Proton Source for the Electrochemical CO Reduction Reaction on Copper Surfaces. Angew Chem Int Ed Engl 2023; 62:e202214210. [PMID: 36369647 DOI: 10.1002/anie.202214210] [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: 09/26/2022] [Revised: 11/10/2022] [Accepted: 11/11/2022] [Indexed: 11/13/2022]
Abstract
We have employed in situ electrochemical shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) and density functional theory (DFT) calculations to study the CO reduction reaction (CORR) on Cu single-crystal surfaces under various conditions. Coadsorbed and structure-/potential-dependent surface species, including *CO, Cu-Oad , and Cu-OHad , were identified using electrochemical spectroscopy and isotope labeling. The relative abundance of *OH follows a "volcano" trend with applied potentials in aqueous solutions, which is yet absent in absolute alcoholic solutions. Combined with DFT calculations, we propose that the surface H2 O can serve as a strong proton donor for the first protonation step in both the C1 and C2 pathways of CORR at various applied potentials in alkaline electrolytes, leaving adsorbed *OH on the surface. This work provides fresh insights into the initial protonation steps and identity of key interfacial intermediates formed during CORR on Cu surfaces.
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Affiliation(s)
- Feng Shao
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing, 211816, China.,Department of Chemistry, Faculty of Science, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Zhaoming Xia
- Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Futian You
- Department of Chemistry, Faculty of Science, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Jun Kit Wong
- Department of Chemistry, Faculty of Science, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Qi Hang Low
- Department of Chemistry, Faculty of Science, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
| | - Hai Xiao
- Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Boon Siang Yeo
- Department of Chemistry, Faculty of Science, National University of Singapore, 3 Science Drive 3, Singapore, 117543, Singapore
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5
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Amirbeigiarab R, Bagger A, Tian J, Rossmeisl J, Magnussen OM. Structure of the (Bi)carbonate Adlayer on Cu(100) Electrodes. Angew Chem Int Ed Engl 2022; 61:e202211360. [PMID: 36122295 PMCID: PMC9827965 DOI: 10.1002/anie.202211360] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Indexed: 01/12/2023]
Abstract
(Bi)carbonate adsorption on Cu(100) in 0.1 M KHCO3 has been studied by in situ scanning tunneling microscopy. Coexistence of different ordered adlayer phases with ( 2 ${\sqrt{2}}$ ×6 2 ${\sqrt{2}}$ )R45° and (4×4) unit cells was observed in the double layer potential regime. The adlayer is rather dynamic and undergoes a reversible order-disorder phase transition at 0 V vs. the reversible hydrogen electrode. Density functional calculations indicate that the adlayer consists of coadsorbed carbonate and water molecules and is strongly stabilized by liquid water in the adjacent electrolyte.
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Affiliation(s)
| | - Alexander Bagger
- Center of High Entropy Alloy Catalysis (CHEAC)Department of ChemistryUniversity of CopenhagenUniversitetsparken 52100CopenhagenDenmark
| | - Jing Tian
- Institute of Experimental and Applied PhysicsKiel University24098KielGermany
| | - Jan Rossmeisl
- Center of High Entropy Alloy Catalysis (CHEAC)Department of ChemistryUniversity of CopenhagenUniversitetsparken 52100CopenhagenDenmark
| | - Olaf M. Magnussen
- Institute of Experimental and Applied PhysicsKiel University24098KielGermany
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6
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Wahab OJ, Kang M, Daviddi E, Walker M, Unwin PR. Screening Surface Structure-Electrochemical Activity Relationships of Copper Electrodes under CO 2 Electroreduction Conditions. ACS Catal 2022; 12:6578-6588. [PMID: 35692254 PMCID: PMC9171721 DOI: 10.1021/acscatal.2c01650] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 05/05/2022] [Indexed: 01/10/2023]
Abstract
Understanding how crystallographic orientation influences the electrocatalytic performance of metal catalysts can potentially advance the design of catalysts with improved efficiency. Although single crystal electrodes are typically used for such studies, the one-at-a-time preparation procedure limits the range of secondary crystallographic orientations that can be profiled. This work employs scanning electrochemical cell microscopy (SECCM) together with co-located electron backscatter diffraction (EBSD) as a screening technique to investigate how surface crystallographic orientations on polycrystalline copper (Cu) correlate to activity under CO2 electroreduction conditions. SECCM measures spatially resolved voltammetry on polycrystalline copper covering low overpotentials of CO2 conversion to intermediates, thereby screening the different activity from low-index facets where H2 evolution is dominant to high-index facets where more reaction intermediates are expected. This approach allows the acquisition of 2500 voltammograms on approximately 60 different Cu surface facets identified with EBSD. The results show that the order of activity is (111) < (100) < (110) among the Cu primary orientations. The collection of data over a wide range of secondary orientations leads to the construction of an "electrochemical-crystallographic stereographic triangle" that provides a broad comprehension of the trends among Cu secondary surface facets rarely studied in the literature, [particularly (941) and (741)], and clearly shows that the electroreduction activity scales with the step and kink density of these surfaces. This work also reveals that the electrochemical stripping of the passive layer that is naturally formed on Cu in air is strongly grain-dependent, and the relative ease of stripping on low-index facets follows the order of (100) > (111) > (110). This allows a procedure to be implemented, whereby the oxide is removed (to an electrochemically undetectable level) prior to the kinetic analyses of electroreduction activity. SECCM screening allows for the most active surfaces to be ranked and prompts in-depth follow-up studies.
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Affiliation(s)
| | - Minkyung Kang
- Institute for Frontier Materials Deakin University, Burwood, Victoria 3125, Australia
| | - Enrico Daviddi
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
| | - Marc Walker
- Department of Physics, University of Warwick, Coventry CV4 7AL, U.K
| | - Patrick R. Unwin
- Department of Chemistry, University of Warwick, Coventry CV4 7AL, U.K
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7
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Korpelin V, Kiljunen T, Melander MM, Caro MA, Kristoffersen HH, Mammen N, Apaja V, Honkala K. Addressing Dynamics at Catalytic Heterogeneous Interfaces with DFT-MD: Anomalous Temperature Distributions from Commonly Used Thermostats. J Phys Chem Lett 2022; 13:2644-2652. [PMID: 35297635 PMCID: PMC8959310 DOI: 10.1021/acs.jpclett.2c00230] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 03/11/2022] [Indexed: 05/28/2023]
Abstract
Density functional theory-based molecular dynamics (DFT-MD) has been widely used for studying the chemistry of heterogeneous interfacial systems under operational conditions. We report frequently overlooked errors in thermostated or constant-temperature DFT-MD simulations applied to study (electro)catalytic chemistry. Our results demonstrate that commonly used thermostats such as Nosé-Hoover, Berendsen, and simple velocity-rescaling methods fail to provide a reliable temperature description for systems considered. Instead, nonconstant temperatures and large temperature gradients within the different parts of the system are observed. The errors are not a "feature" of any particular code but are present in several ab initio molecular dynamics implementations. This uneven temperature distribution, due to inadequate thermostatting, is well-known in the classical MD community, where it is ascribed to the failure in kinetic energy equipartition among different degrees of freedom in heterogeneous systems (Harvey et al. J. Comput. Chem. 1998, 726-740) and termed the flying ice cube effect. We provide tantamount evidence that interfacial systems are susceptible to substantial flying ice cube effects and demonstrate that the traditional Nosé-Hoover and Berendsen thermostats should be applied with care when simulating, for example, catalytic properties or structures of solvated interfaces and supported clusters. We conclude that the flying ice cube effect in these systems can be conveniently avoided using Langevin dynamics.
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Affiliation(s)
- Ville Korpelin
- Department
of Chemistry, Nanoscience Center, University
of Jyväskylä, P.O. Box 35 (YN), FI-40014 Jyväskylä, Finland
| | - Toni Kiljunen
- Department
of Chemistry, Nanoscience Center, University
of Jyväskylä, P.O. Box 35 (YN), FI-40014 Jyväskylä, Finland
| | - Marko M. Melander
- Department
of Chemistry, Nanoscience Center, University
of Jyväskylä, P.O. Box 35 (YN), FI-40014 Jyväskylä, Finland
| | - Miguel A. Caro
- Department
of Electrical Engineering and Automation, Aalto University, FIN-02150 Espoo, Finland
| | | | - Nisha Mammen
- Department
of Physics,Nanoscience Center, University
of Jyväskylä, P.O. Box
35 (YN), FI-40014 Jyväskylä, Finland
| | - Vesa Apaja
- Department
of Physics,Nanoscience Center, University
of Jyväskylä, P.O. Box
35 (YN), FI-40014 Jyväskylä, Finland
| | - Karoliina Honkala
- Department
of Chemistry, Nanoscience Center, University
of Jyväskylä, P.O. Box 35 (YN), FI-40014 Jyväskylä, Finland
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8
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Bagger A, Christensen O, Ivaništšev V, Rossmeisl J. Catalytic CO2/CO Reduction: Gas, Aqueous, and Aprotic Phases. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05358] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Alexander Bagger
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Oliver Christensen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Vladislav Ivaništšev
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
- Institute of Chemistry, University of Tartu, 50411 Tartu, Estonia
| | - Jan Rossmeisl
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
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9
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Artmann E, Menezes PV, Forschner L, Elnagar MM, Kibler LA, Jacob T, Engstfeld AK. Structural Evolution of Pt, Au and Cu Anodes by Electrolysis up to Contact Glow Discharge Electrolysis in Alkaline Electrolytes*. Chemphyschem 2021; 22:2429-2441. [PMID: 34523210 PMCID: PMC9298152 DOI: 10.1002/cphc.202100433] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 08/10/2021] [Indexed: 01/09/2023]
Abstract
Applying a voltage to metal electrodes in contact with aqueous electrolytes results in the electrolysis of water at voltages above the decomposition voltage and plasma formation in the electrolyte at much higher voltages referred to as contact glow discharge electrolysis (CGDE). While several studies explore parameters that lead to changes in the I–U characteristics in this voltage range, little is known about the evolution of the structural properties of the electrodes. Here we study this aspect on materials essential to electrocatalysis, namely Pt, Au, and Cu. The stationary I–U characteristics are almost identical for all electrodes. Detailed structural characterization by optical microscopy, scanning electron microscopy, and electrochemical approaches reveal that Pt is stable during electrolysis and CGDE, while Au and Cu exhibit a voltage‐dependent oxide formation. More importantly, oxides are reduced when the Au and Cu electrodes are kept in the electrolysis solution after electrolysis. We suspect that H2O2 (formed during electrolysis) is responsible for the oxide reduction. The reduced oxides (which are also accessible via electrochemical reduction) form a porous film, representing a possible new class of materials in energy storage and conversion studies.
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Affiliation(s)
- Evelyn Artmann
- Institute of Electrochemistry, Ulm University, D-, 89081, Ulm, Germany
| | - Pramod V Menezes
- Institute of Electrochemistry, Ulm University, D-, 89081, Ulm, Germany
| | - Lukas Forschner
- Institute of Electrochemistry, Ulm University, D-, 89081, Ulm, Germany
| | - Mohamed M Elnagar
- Institute of Electrochemistry, Ulm University, D-, 89081, Ulm, Germany
| | - Ludwig A Kibler
- Institute of Electrochemistry, Ulm University, D-, 89081, Ulm, Germany
| | - Timo Jacob
- Institute of Electrochemistry, Ulm University, D-, 89081, Ulm, Germany
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10
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Abstract
The electronic and optical properties of polythiophene (PT) for polymer light-emitting diodes (PLEDs) were calculated using density functional theory (DFT) and time-dependent DFT. We calculated the electronic and optical properties of thiophene and PT polymers with degrees of polymerization (DP) from 2 to 30 monomers (T1–T30) and their derivatives. The associated highest occupied molecular orbital (HOMO) energy, lowest unoccupied molecular orbital (LUMO) energy, band gaps, electron orbitals, and molecular structures were determined. As the DP increased, the LUMO energy gradually decreased, and the HOMO energy gradually increased. The band gap of PT approached 2 eV as the DP of the PT polymer increased from 1 to 30. The calculations and exchange–correlation functional were verified against values in the literature and experimental data from cyclic voltammetry (redox potential) and ultraviolet-visible, photoluminescence, and ultraviolet photoelectron spectra. The color of PT PLEDs can be adjusted by controlling the DP of the polymer and the substituents.
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11
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Ostervold L, Perez Bakovic SI, Hestekin J, Greenlee LF. Electrochemical biomass upgrading: degradation of glucose to lactic acid on a copper(ii) electrode. RSC Adv 2021; 11:31208-31218. [PMID: 35496889 PMCID: PMC9041372 DOI: 10.1039/d1ra06737k] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 09/15/2021] [Indexed: 12/22/2022] Open
Abstract
Biomass upgrading - the conversion of biomass waste into value-added products - provides a possible solution to reduce global dependency on nonrenewable resources. This study investigates the possibility of green biomass upgrading for lactic acid production by electrochemically-driven degradation of glucose. Herein we report an electrooxidized copper(ii) electrode which exhibits a turnover frequency of 5.04 s-1 for glucose conversion. Chronoamperometry experiments under varied potentials, alkalinity, and electrode preparation achieved a maximum lactic acid yield of 23.3 ± 1.2% and selectivity of 31.1 ± 1.9% (1.46 V vs. RHE, 1.0 M NaOH) for a room temperature and open-to-atmosphere reaction. Comparison between reaction conditions revealed lactic acid yield depends on alkalinity and applied potential, while pre-oxidation of the copper had a negligible effect on yield. Post-reaction cyclic voltammetry studies indicated no loss in reactivity for copper(ii) electrodes after a 30 hour reaction. Finally, a mechanism dependent on solvated Cu2+ species is proposed as evidenced by similar product distributions in electrocatalytic and thermocatalytic systems.
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Affiliation(s)
- Lars Ostervold
- Department of Chemical Engineering, Pennsylvania State University University Park PA USA .,Ralph E. Martin Department of Chemical Engineering Fayetteville AR USA
| | | | - Jamie Hestekin
- Ralph E. Martin Department of Chemical Engineering Fayetteville AR USA
| | - Lauren F Greenlee
- Department of Chemical Engineering, Pennsylvania State University University Park PA USA .,Ralph E. Martin Department of Chemical Engineering Fayetteville AR USA
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12
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Surface characterization of copper electrocatalysts by lead underpotential deposition. J Electroanal Chem (Lausanne) 2021. [DOI: 10.1016/j.jelechem.2021.115446] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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13
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Bruce JP, Nguyen KLC, Scholten F, Arán-Ais RM, Navarro JJ, Hartmann J, Heyde M, Cuenya BR. Development of a single crystal sample holder for interfacing ultrahigh vacuum and electrochemical experimentation. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2021; 92:074104. [PMID: 34340410 DOI: 10.1063/5.0057822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Accepted: 07/01/2021] [Indexed: 06/13/2023]
Abstract
Electrocatalyst surfaces prepared under ultrahigh vacuum (UHV) conditions can create model surfaces to better connect theoretical calculations with experimental studies. The development of a single crystal sample holder and inert electrochemical cells prepared with modularity and chemical stability in mind would allow for expensive single crystals to be reused indefinitely in both UHV and electrochemical settings. This sample holder shows reproducible surface preparations for single crystal samples and consistent electrochemical experiments without the introduction of impurities into the surface. The presented setup has been used as a critical piece for the characterization of Cu(111) surfaces under CO2 electrochemical reduction reaction conditions as a test case.
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Affiliation(s)
- Jared P Bruce
- Fritz Haber Institute of the Max Planck Society, Department of Interface Science, Faradayweg 4-6, Berlin 14195, Germany
| | - Khanh-Ly C Nguyen
- Fritz Haber Institute of the Max Planck Society, Department of Interface Science, Faradayweg 4-6, Berlin 14195, Germany
| | - Fabian Scholten
- Fritz Haber Institute of the Max Planck Society, Department of Interface Science, Faradayweg 4-6, Berlin 14195, Germany
| | - Rosa M Arán-Ais
- Fritz Haber Institute of the Max Planck Society, Department of Interface Science, Faradayweg 4-6, Berlin 14195, Germany
| | - Juan J Navarro
- Fritz Haber Institute of the Max Planck Society, Department of Interface Science, Faradayweg 4-6, Berlin 14195, Germany
| | - Jens Hartmann
- Fritz Haber Institute of the Max Planck Society, Department of Interface Science, Faradayweg 4-6, Berlin 14195, Germany
| | - Markus Heyde
- Fritz Haber Institute of the Max Planck Society, Department of Interface Science, Faradayweg 4-6, Berlin 14195, Germany
| | - Beatriz Roldan Cuenya
- Fritz Haber Institute of the Max Planck Society, Department of Interface Science, Faradayweg 4-6, Berlin 14195, Germany
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14
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Geppert J, Kubannek F, Röse P, Krewer U. Identifying the oxygen evolution mechanism by microkinetic modelling of cyclic voltammograms. Electrochim Acta 2021. [DOI: 10.1016/j.electacta.2021.137902] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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15
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Hörmann NG, Reuter K. Thermodynamic cyclic voltammograms: peak positions and shapes. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:264004. [PMID: 33848987 DOI: 10.1088/1361-648x/abf7a1] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2021] [Accepted: 04/13/2021] [Indexed: 06/12/2023]
Abstract
Based on a mean-field description of thermodynamic cyclic voltammograms (CVs), we analyze here in full generality, how CV peak positions and shapes are related to the underlying interface energetics, in particular when also including electrostatic double layer (DL) effects. We show in particular, how non-Nernstian behaviour is related to capacitive DL charging, and how this relates to common adsorbate-centered interpretations such as a changed adsorption energetics due to dipole-field interactions and the electrosorption valency - the number of exchanged electrons upon electrosorption per adsorbate. Using Ag(111) in halide-containing solutions as test case, we demonstrate that DL effects can introduce peak shifts that are already explained by rationalizing the interaction of isolated adsorbates with the interfacial fields, while alterations of the peak shape are mainly driven by the coverage-dependence of the adsorbate dipoles. In addition, we analyze in detail how changing the experimental conditions such as the ion concentrations in the solvent but also of the background electrolyte can affect the CV peaks via their impact on the potential drop in the DL and the DL capacitance, respectively. These results suggest new routes to analyze experimental CVs and use of those for a detailed assessment of the accuracy of atomistic models of electrified interfaces e.g. with and without explicitly treated interfacial solvent and/or approximate implicit solvent models.
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Affiliation(s)
- Nicolas Georg Hörmann
- Theoretical Chemistry, Technische Universitaet Muenchen, Lichtenbergstraße 4, Garching, DE 85748, Germany
- Theory, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, Berlin, DE 14195, Germany
| | - Karsten Reuter
- Theory, Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, Berlin, DE 14195, Germany
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16
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Jeon HS, Timoshenko J, Rettenmaier C, Herzog A, Yoon A, Chee SW, Oener S, Hejral U, Haase FT, Roldan Cuenya B. Selectivity Control of Cu Nanocrystals in a Gas-Fed Flow Cell through CO 2 Pulsed Electroreduction. J Am Chem Soc 2021; 143:7578-7587. [PMID: 33956433 PMCID: PMC8154520 DOI: 10.1021/jacs.1c03443] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
![]()
In this study, we
have taken advantage of a pulsed CO2 electroreduction reaction
(CO2RR) approach to tune the
product distribution at industrially relevant current densities in
a gas-fed flow cell. We compared the CO2RR selectivity
of Cu catalysts subjected to either potentiostatic conditions (fixed
applied potential of −0.7 VRHE) or pulsed electrolysis
conditions (1 s pulses at oxidative potentials ranging from Ean = 0.6 to 1.5 VRHE, followed by
1 s pulses at −0.7 VRHE) and identified the main
parameters responsible for the enhanced product selectivity observed
in the latter case. Herein, two distinct regimes were observed: (i)
for Ean = 0.9 VRHE we obtained
10% enhanced C2 product selectivity (FEC2H4 = 43.6% and FEC2H5OH = 19.8%) in comparison to the potentiostatic CO2RR at −0.7 VRHE (FEC2H4 = 40.9% and FEC2H5OH = 11%),
(ii) while for Ean = 1.2 VRHE, high CH4 selectivity (FECH4 =
48.3% vs 0.1% at constant −0.7 VRHE) was observed. Operando spectroscopy (XAS, SERS) and ex situ microscopy (SEM and TEM) measurements revealed that these differences
in catalyst selectivity can be ascribed to structural modifications
and local pH effects. The morphological reconstruction of the catalyst
observed after pulsed electrolysis with Ean = 0.9 VRHE, including the presence of highly defective
interfaces and grain boundaries, was found to play a key role in the
enhancement of the C2 product formation. In turn, pulsed
electrolysis with Ean = 1.2 VRHE caused the consumption
of OH– species near the catalyst surface, leading
to an OH-poor environment favorable for CH4 production.
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Affiliation(s)
- Hyo Sang Jeon
- Department of Interface Science, Fritz-Haber Institute of the Max-Planck Society, 14195 Berlin, Germany
| | - Janis Timoshenko
- Department of Interface Science, Fritz-Haber Institute of the Max-Planck Society, 14195 Berlin, Germany
| | - Clara Rettenmaier
- Department of Interface Science, Fritz-Haber Institute of the Max-Planck Society, 14195 Berlin, Germany
| | - Antonia Herzog
- Department of Interface Science, Fritz-Haber Institute of the Max-Planck Society, 14195 Berlin, Germany
| | - Aram Yoon
- Department of Interface Science, Fritz-Haber Institute of the Max-Planck Society, 14195 Berlin, Germany
| | - See Wee Chee
- Department of Interface Science, Fritz-Haber Institute of the Max-Planck Society, 14195 Berlin, Germany
| | - Sebastian Oener
- Department of Interface Science, Fritz-Haber Institute of the Max-Planck Society, 14195 Berlin, Germany
| | - Uta Hejral
- Department of Interface Science, Fritz-Haber Institute of the Max-Planck Society, 14195 Berlin, Germany
| | - Felix T Haase
- Department of Interface Science, Fritz-Haber Institute of the Max-Planck Society, 14195 Berlin, Germany
| | - Beatriz Roldan Cuenya
- Department of Interface Science, Fritz-Haber Institute of the Max-Planck Society, 14195 Berlin, Germany
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17
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Auer A, Ding X, Bandarenka AS, Kunze-Liebhäuser J. The Potential of Zero Charge and the Electrochemical Interface Structure of Cu(111) in Alkaline Solutions. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2021; 125:5020-5028. [PMID: 33828636 PMCID: PMC8016203 DOI: 10.1021/acs.jpcc.0c09289] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 02/16/2021] [Indexed: 05/09/2023]
Abstract
Copper (Cu) is a unique electrocatalyst, which is able to efficiently oxidize CO at very low overpotentials and reduce CO2 to valuable fuels with reasonable Faradaic efficiencies. Yet, knowledge of its electrochemical properties at the solid/liquid interface is still scarce. Here, we present the first two-stranded correlation of the potential of zero free charge (pzfc) of Cu(111) in alkaline electrolyte at different pH values through application of nanosecond laser pulses and the corresponding interfacial structure changes by in situ electrochemical scanning tunneling microscopy imaging. The pzfc of Cu(111) at pH 13 is identified at -0.73 VSHE in the apparent double layer region, prior to the onset of hydroxide adsorption. It shifts by (88 ± 4) mV to more positive potentials per decreasing pH unit. At the pzfc, Cu(111) shows structural dynamics at both pH 13 and pH 11, which can be understood as the onset of surface restructuring. At higher potentials, full reconstruction and electric field dependent OH adsorption occurs, which causes a remarkable decrease in the atomic density of the first Cu layer. The expansion of the Cu-Cu distance to 0.3 nm generates a hexagonal Moiré pattern, on which the adsorbed OH forms a commensurate (1 × 2) adlayer structure with a steady state coverage of 0.5 monolayers at pH 13. Our experimental findings shed light on the true charge distribution and its interrelation with the atomic structure of the electrochemical interface of Cu.
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Affiliation(s)
- Andrea Auer
- Institute
of Physical Chemistry, University Innsbruck, Innrain 52c, Innsbruck, 6020, Austria
| | - Xing Ding
- Physics
of Energy Conversion and Storage (ECS), Physics Department, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany
| | - Aliaksandr S. Bandarenka
- Physics
of Energy Conversion and Storage (ECS), Physics Department, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany
- Catalysis
Research Center TUM, Ernst-Otto-Fischer-Straße 1, 85748 Garching, Germany
- E-mail: (A.S.B.)
| | - Julia Kunze-Liebhäuser
- Institute
of Physical Chemistry, University Innsbruck, Innrain 52c, Innsbruck, 6020, Austria
- E-mail: (J.K.-L.)
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18
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Hörmann NG, Reuter K. Thermodynamic Cyclic Voltammograms Based on Ab Initio Calculations: Ag(111) in Halide-Containing Solutions. J Chem Theory Comput 2021; 17:1782-1794. [PMID: 33606513 PMCID: PMC8023662 DOI: 10.1021/acs.jctc.0c01166] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Cyclic voltammograms
(CVs) are a central experimental tool for
assessing the structure and activity of electrochemical interfaces.
Based on a mean-field ansatz for the interface energetics under applied
potential conditions, we here derive an ab initio thermodynamics approach to efficiently simulate thermodynamic CVs.
All unknown parameters are determined from density functional theory
(DFT) calculations coupled to an implicit solvent model. For the showcased
CVs of Ag(111) electrodes in halide-anion-containing solutions, these
simulations demonstrate the relevance of double-layer contributions
to explain experimentally observed differences in peak shapes over
the halide series. Only the appropriate account of interfacial charging
allows us to capture the differences in equilibrium coverage and total
electronic surface charge that cause the varying peak shapes. As a
case in point, this analysis demonstrates that prominent features
in CVs do not only derive from changes in adsorbate structure or coverage
but can also be related to variations of the electrosorption valency.
Such double-layer effects are proportional to adsorbate-induced changes
in the work function and/or interfacial capacitance. They are thus
especially pronounced for electronegative halides and other adsorbates
that affect these interface properties. In addition, the analysis
allows us to draw conclusions on how the possible inaccuracy of implicit
solvation models can indirectly affect the accuracy of other predicted
quantities such as CVs.
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Affiliation(s)
- Nicolas G Hörmann
- Chair of Theoretical Chemistry and Catalysis Research Center, Technische Universität München, Lichtenbergstr. 4, 85748 Garching, Germany.,Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
| | - Karsten Reuter
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
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19
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Baricuatro JH, Kwon S, Kim YG, Cummins KD, Naserifar S, Goddard WA. Operando Electrochemical Spectroscopy for CO on Cu(100) at pH 1 to 13: Validation of Grand Canonical Potential Predictions. ACS Catal 2021. [DOI: 10.1021/acscatal.0c05564] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jack H. Baricuatro
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Soonho Kwon
- Liquid Sunlight Alliance (LiSA) and Materials and Process Simulation Center (MSC), California Institute of Technology, Pasadena, California 91125, United States
| | - Youn-Geun Kim
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Kyle D. Cummins
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Saber Naserifar
- Liquid Sunlight Alliance (LiSA) and Materials and Process Simulation Center (MSC), California Institute of Technology, Pasadena, California 91125, United States
| | - William A. Goddard
- Liquid Sunlight Alliance (LiSA) and Materials and Process Simulation Center (MSC), California Institute of Technology, Pasadena, California 91125, United States
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20
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Sebastián-Pascual P, Petersen AS, Bagger A, Rossmeisl J, Escudero-Escribano M. pH and Anion Effects on Cu–Phosphate Interfaces for CO Electroreduction. ACS Catal 2021. [DOI: 10.1021/acscatal.0c03998] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Paula Sebastián-Pascual
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Amanda S. Petersen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Alexander Bagger
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - Jan Rossmeisl
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
| | - María Escudero-Escribano
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark
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21
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Uncovering the electrochemical interface of low-index copper surfaces in deep groundwater environments. Electrochim Acta 2020. [DOI: 10.1016/j.electacta.2020.137111] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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22
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Abidi N, Lim KRG, Seh ZW, Steinmann SN. Atomistic modeling of electrocatalysis: Are we there yet? WILEY INTERDISCIPLINARY REVIEWS-COMPUTATIONAL MOLECULAR SCIENCE 2020. [DOI: 10.1002/wcms.1499] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Nawras Abidi
- Univ Lyon, Ens de Lyon, CNRS UMR 5182 Université Claude Bernard Lyon 1, Laboratoire de Chimie, F69342, Lyon France
| | - Kang Rui Garrick Lim
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR) Singapore
| | - Zhi Wei Seh
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research (A*STAR) Singapore
| | - Stephan N. Steinmann
- Univ Lyon, Ens de Lyon, CNRS UMR 5182 Université Claude Bernard Lyon 1, Laboratoire de Chimie, F69342, Lyon France
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23
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Tayyebi E, Hussain J, Skúlason E. Why do RuO 2 electrodes catalyze electrochemical CO 2 reduction to methanol rather than methane or perhaps neither of those? Chem Sci 2020; 11:9542-9553. [PMID: 34094219 PMCID: PMC8161686 DOI: 10.1039/d0sc01882a] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The electrochemical CO2 reduction reaction (CO2RR) on RuO2 and RuO2-based electrodes has been shown experimentally to produce high yields of methanol, formic acid and/or hydrogen while methane formation is not detected. This CO2RR selectivity on RuO2 is in stark contrast to copper metal electrodes that produce methane and hydrogen in the highest yields whereas methanol is only formed in trace amounts. Density functional theory calculations on RuO2(110) where only adsorption free energies of intermediate species are considered, i.e. solvent effects and energy barriers are not included, predict however, that the overpotential and the potential limiting step for both methanol and methane are the same. In this work, we use both ab initio molecular dynamics simulations at room temperature and total energy calculations to improve the model system and methodology by including both explicit solvation effects and calculations of proton–electron transfer energy barriers to elucidate the reaction mechanism towards several CO2RR products: methanol, methane, formic acid, CO and methanediol, as well as for the competing H2 evolution. We observe a significant difference in energy barriers towards methane and methanol, where a substantially larger energy barrier is calculated towards methane formation than towards methanol formation, explaining why methanol has been detected experimentally but not methane. Furthermore, the calculations show why RuO2 also catalyzes the CO2RR towards formic acid and not CO(g) and methanediol, in agreement with experimental results. However, our calculations predict RuO2 to be much more selective towards H2 formation than for the CO2RR at any applied potential. Only when a large overpotential of around −1 V is applied, can both formic acid and methanol be evolved, but low faradaic efficiency is predicted because of the more facile H2 formation. Energy barriers are calculated for the electrochemical CO2 reduction reaction on the RuO2(110) surface towards methanol, methane, formic acid, methanediol, CO and the competing H2 formation and compared with experimental literature.![]()
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Affiliation(s)
- Ebrahim Tayyebi
- Science Institute, University of Iceland VR-III 107 Reykjavík Iceland
| | - Javed Hussain
- Science Institute, University of Iceland VR-III 107 Reykjavík Iceland
| | - Egill Skúlason
- Science Institute, University of Iceland VR-III 107 Reykjavík Iceland .,Faculty of Industrial Engineering, Mechanical Engineering and Computer Science, University of Iceland VR-III 107 Reykjavík Iceland
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24
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Gunathunge CM, Li J, Li X, Hong JJ, Waegele MM. Revealing the Predominant Surface Facets of Rough Cu Electrodes under Electrochemical Conditions. ACS Catal 2020. [DOI: 10.1021/acscatal.9b05532] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
- Charuni M. Gunathunge
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Jingyi Li
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Xiang Li
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Julie J. Hong
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States
| | - Matthias M. Waegele
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467, United States
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25
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Ting LRL, Piqué O, Lim SY, Tanhaei M, Calle-Vallejo F, Yeo BS. Enhancing CO2 Electroreduction to Ethanol on Copper–Silver Composites by Opening an Alternative Catalytic Pathway. ACS Catal 2020. [DOI: 10.1021/acscatal.9b05319] [Citation(s) in RCA: 84] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Louisa Rui Lin Ting
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
- Solar Energy Research Institute of Singapore, National University of Singapore, 7 Engineering Drive 1, Singapore 117574
| | - Oriol Piqué
- Departament de Ciència de Materials i Química Física & Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - Si Ying Lim
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
- Solar Energy Research Institute of Singapore, National University of Singapore, 7 Engineering Drive 1, Singapore 117574
| | - Mohammad Tanhaei
- Institute of Materials Research and Engineering, Agency for Science, Technology and Research, 2 Fusionopolis Way, Singapore 138634
| | - Federico Calle-Vallejo
- Departament de Ciència de Materials i Química Física & Institut de Química Teòrica i Computacional (IQTCUB), Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain
| | - Boon Siang Yeo
- Department of Chemistry, National University of Singapore, 3 Science Drive 3, Singapore 117543
- Solar Energy Research Institute of Singapore, National University of Singapore, 7 Engineering Drive 1, Singapore 117574
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26
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Tiwari A, Heenen HH, Bjørnlund AS, Maagaard T, Cho E, Chorkendorff I, Kristoffersen HH, Chan K, Horch S. Fingerprint Voltammograms of Copper Single Crystals under Alkaline Conditions: A Fundamental Mechanistic Analysis. J Phys Chem Lett 2020; 11:1450-1455. [PMID: 32022563 DOI: 10.1021/acs.jpclett.9b03728] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
A critical step toward the systematic development of electrocatalysts is the determination of the microscopic structure and processes at the electrified solid/electrolyte interface. The major challenges toward this end for experiment and computations are achieving sufficient cleanliness and modeling the complexity of electrochemical systems, respectively. In this sense, benchmarks of well-defined model systems are sparse. This work presents a rigorous joint experimental-theoretical study on the single-crystal (SC) Cu/aqueous interface. Within typical computational uncertainties, we find quantitative agreement between simulated and experimentally measured voltammograms, which allows us to unequivocally identify the *OH adsorption feature in the fingerprint region of Cu(110), Cu(100), and Cu(111) SCs under alkaline conditions. We find the inclusion of hydrogen evolution reaction kinetics in the theoretical model to be crucial for an accurate steady-state description that gives rise to a negligible H* coverage. A purely thermodynamic description of the H* coverage through a Pourbaix analysis would incorrectly lead to a H* adsorption peak. The presented results establish a fundamental benchmark for all electrochemical applications of Cu.
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Affiliation(s)
- Aarti Tiwari
- Department of Physics , Technical University of Denmark (DTU) , Fysikvej 311 , 2800 Kgs. Lyngby , Denmark
| | - Hendrik H Heenen
- Department of Physics , Technical University of Denmark (DTU) , Fysikvej 311 , 2800 Kgs. Lyngby , Denmark
| | - Anton Simon Bjørnlund
- Department of Physics , Technical University of Denmark (DTU) , Fysikvej 311 , 2800 Kgs. Lyngby , Denmark
| | - Thomas Maagaard
- Department of Physics , Technical University of Denmark (DTU) , Fysikvej 311 , 2800 Kgs. Lyngby , Denmark
| | - EunAe Cho
- Department of Materials Science and Engineering , KAIST , Yuseong-gu, Daejeon 305-701 , Republic of Korea
| | - Ib Chorkendorff
- Department of Physics , Technical University of Denmark (DTU) , Fysikvej 311 , 2800 Kgs. Lyngby , Denmark
| | - Henrik H Kristoffersen
- Department of Physics , Technical University of Denmark (DTU) , Fysikvej 311 , 2800 Kgs. Lyngby , Denmark
| | - Karen Chan
- Department of Physics , Technical University of Denmark (DTU) , Fysikvej 311 , 2800 Kgs. Lyngby , Denmark
| | - Sebastian Horch
- Department of Physics , Technical University of Denmark (DTU) , Fysikvej 311 , 2800 Kgs. Lyngby , Denmark
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27
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Chen X, Granda-Marulanda LP, McCrum IT, Koper MTM. Adsorption processes on a Pd monolayer-modified Pt(111) electrode. Chem Sci 2020; 11:1703-1713. [PMID: 34084392 PMCID: PMC8148025 DOI: 10.1039/c9sc05307g] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Specific adsorption of anions is an important aspect in surface electrochemistry for its influence on reaction kinetics in either a promoted or inhibited fashion. Perchloric acid is typically considered as an ideal electrolyte for investigating electrocatalytic reactions due to the lack of specific adsorption of the perchlorate anion on several metal electrodes. In this work, cyclic voltammetry and computational methods are combined to investigate the interfacial processes on a Pd monolayer deposited on Pt(111) single crystal electrode in perchloric acid solution. The “hydrogen region” of this PdMLPt(111) surface exhibits two voltammetric peaks: the first “hydrogen peak” at 0.246 VRHE actually involves the replacement of hydrogen by hydroxyl, and the second “hydrogen peak” HII at 0.306 VRHE appears to be the replacement of adsorbed hydroxyl by specific perchlorate adsorption. The two peaks merge into a single peak when a more strongly adsorbed anion, such as sulfate, is involved. Our density functional theory calculations qualitatively support the peak assignment and show that anions generally bind more strongly to the PdMLPt(111) surface than to Pt(111). Specific adsorption of anions is an important aspect in surface electrochemistry for its influence on reaction kinetics in either a promoted or inhibited fashion.![]()
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Affiliation(s)
- Xiaoting Chen
- Leiden Institute of Chemistry, Leiden University PO Box 9502 Leiden 2300 RA The Netherlands
| | | | - Ian T McCrum
- Leiden Institute of Chemistry, Leiden University PO Box 9502 Leiden 2300 RA The Netherlands
| | - Marc T M Koper
- Leiden Institute of Chemistry, Leiden University PO Box 9502 Leiden 2300 RA The Netherlands
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