Constant inner potential DFT for modelling electrochemical systems under constant potential and bias

npj Computational Materials, Journal Year: 2024, Volume and Issue: 10(1)

Published: Jan. 5, 2024

Abstract Electrochemical systems play a decisive role in, e.g. clean energy conversion but understanding their complex chemistry remains an outstanding challenge. Constant potential and grand canonical ensemble (GCE) simulations are indispensable for unraveling the properties of electrochemical processes as function electrode potential. Currently, GCE calculations performed at density functional theory (DFT) level require fixing Fermi within simulation cell. Here, we illustrate that this method is inadequate when modeling outer sphere reactions biased two-electrode For these systems, obtained from DFT does not accurately present experimentally controlled or describe thermodynamic independent variable in GCE-DFT. To address limitation, developed implemented constant inner (CIP) offering more robust general approach to conducting GCE-DFT under bias conditions. The primary advantage CIP it uses local parameter potential, opposed global level. Through numerical analytical studies, demonstrate approaches equivalent metallic electrodes inner-sphere reactions. However, proves be versatile, can applied outer-sphere addressing limitations Fermi-level scenarios. Altogether, stands out efficient simulating interfaces first principles.

Language: Английский

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Mechanistic Insights into Surfactant-Modulated Electrode–Electrolyte Interface for Steering H₂O₂ Electrosynthesis

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(11), P. 7575 - 7583

Published: March 11, 2024

Electrocatalytic reactions taking place at the electrified electrode–electrolyte interface involve processes of proton-coupled electron transfer. Interfacial protons are delivered to electrode surface via a H2O-dominated hydrogen-bond network. Less efforts made regulate interfacial proton transfer from perspective Here, we present quaternary ammonium salt cationic surfactants as electrolyte additives for enhancing H2O2 selectivity oxygen reduction reaction (ORR). Through in situ vibrational spectroscopy and molecular dynamics calculation, it is revealed that irreversibly adsorbed on response given bias potential range, leading weakening This decreases kinetics, particularly high potentials, thus suppressing 4-electron ORR pathway achieving highly selective 2-electron toward H2O2. These results highlight opportunity steering H2O-involved electrochemical modulating

Language: Английский

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Emerging Atomistic Modeling Methods for Heterogeneous Electrocatalysis

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(14), P. 8620 - 8656

Published: July 11, 2024

Heterogeneous electrocatalysis lies at the center of various technologies that could help enable a sustainable future. However, its complexity makes it challenging to accurately and efficiently model an atomic level. Here, we review emerging atomistic methods simulate electrocatalytic interface with special attention devoted components/effects have been model, such as solvation, electrolyte ions, electrode potential, reaction kinetics, pH. Additionally, relevant computational spectroscopy methods. Then, showcase several examples applying these understand design catalysts green hydrogen. We also offer experimental views on how bridge gap between theory experiments. Finally, provide some perspectives opportunities advance field.

Language: Английский

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Toward Realistic Models of the Electrocatalytic Oxygen Evolution Reaction

Chemical Reviews, Journal Year: 2024, Volume and Issue: 124(15), P. 9136 - 9223

Published: July 22, 2024

The electrocatalytic oxygen evolution reaction (OER) supplies the protons and electrons needed to transform renewable electricity into chemicals fuels. However, OER is kinetically sluggish; it operates at significant rates only when applied potential far exceeds reversible voltage. origin of this overpotential hidden in a complex mechanism involving multiple electron transfers chemical bond making/breaking steps. Our desire improve catalytic performance has then made mechanistic studies an area major scientific inquiry, though complexity understanding difficult. While historically, have relied solely on experiment phenomenological models, over past twenty years

Language: Английский

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CO2-to-methanol electroconversion on a molecular cobalt catalyst facilitated by acidic cations

Nature Catalysis, Journal Year: 2024, Volume and Issue: 7(9), P. 1000 - 1009

Published: July 22, 2024

Language: Английский

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A molecular-level mechanistic framework for interfacial proton-coupled electron transfer kinetics

Nature Chemistry, Journal Year: 2024, Volume and Issue: 16(3), P. 343 - 352

Published: Jan. 16, 2024

Language: Английский

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Computational Insights on Structural Sensitivity of Cobalt in NO Electroreduction to Ammonia and Hydroxylamine

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(20), P. 13974 - 13982

Published: May 9, 2024

It has been reported that it was selective to produce ammonia on metallic cobalt in the electrocatalytic nitric oxide reduction reaction (eNORR), where hexagonal close-packed (hcp) outperforms face-centered cubic (fcc) cobalt. However, hydroxylamine is more selectively produced a single-atom catalyst (Co-SAC). Herein, we uncover structural sensitivity over hcp-Co, fcc-Co, and Co-SAC eNORR by employing recently developed constant potential simulation method microkinetic modeling. found superior activity for production hcp-Co can be attributed its facile electron proton transfer stronger lateral suppression effect from NO* fcc-Co. The exceptional selectivity due modified electronic structure, namely, positively charged active center. favorable NOH* while HNO* preferable Co-SAC, which are firmly correlated with vertical strong NO adsorption former moderate latter. In other words, key factor control first step of protonation. Therefore, local structure catalysts critical regulating eNORR.

Language: Английский

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Effects of Ionic Interferents on Electrocatalytic Nitrate Reduction: Mechanistic Insight

Environmental Science & Technology, Journal Year: 2024, Volume and Issue: 58(29), P. 12823 - 12845

Published: July 2, 2024

Nitrate, a prevalent water pollutant, poses substantial public health concerns and environmental risks. Electrochemical reduction of nitrate (eNO

Language: Английский

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Multilevel Computational Studies Reveal the Importance of Axial Ligand for Oxygen Reduction Reaction on Fe–N–C Materials

Journal of the American Chemical Society, Journal Year: 2022, Volume and Issue: 144(36), P. 16524 - 16534

Published: Aug. 24, 2022

The systematic improvement of Fe–N–C materials for fuel cell applications has proven challenging, due in part to an incomplete atomistic understanding the oxygen reduction reaction (ORR) under electrochemical conditions. Herein, a multilevel computational approach, which combines ab initio molecular dynamics simulations and constant potential density functional theory calculations, is used assess proton-coupled electron transfer (PCET) processes adsorption thermodynamics key ORR intermediates. These calculations indicate that potential-limiting step on formation FeIII–OOH intermediate. They also show active site model with water molecule axially ligated iron center throughout catalytic cycle produces results are consistent experimental measurements. In particular, reliable prediction onset Fe(III/II) redox associated conversion FeIII–OH FeII desorbed H2O requires axial co-adsorbed center. observation five-coordinate rather than four-coordinate significant implications mechanism ORR. findings highlight importance solvent–substrate interactions surface charge effects PCET mechanisms transition-metal couples realistic

Language: Английский

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Inverse kinetic isotope effects in the oxygen reduction reaction at platinum single crystals

Nature Chemistry, Journal Year: 2022, Volume and Issue: 15(2), P. 271 - 277

Published: Nov. 10, 2022

Language: Английский

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