Cation-Induced Interfacial Hydrophobic Microenvironment Promotes the C–C Coupling in Electrochemical CO₂ Reduction

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(8), С. 5532 - 5542

Опубликована: Фев. 16, 2024

The electrochemical carbon dioxide reduction reaction (CO2RR) toward C2 products is a promising way for the clean energy economy. Modulating structure of electric double layer (EDL), especially interfacial water and cation type, useful strategy to promote C–C coupling, but atomic understanding lags far behind experimental observations. Herein, we investigate combined effect alkali metal cations on coupling at Cu(100) electrode/electrolyte interface using ab initio molecular dynamics (AIMD) simulations with constrained MD slow-growth approach. We observe linear correlation between water-adsorbate stabilization effect, which manifests as hydrogen bonds, corresponding alleviation in free energy. role larger cation, compared smaller (e.g., K+ vs Li+), lies its ability approach through desolvation coordinates *CO+*CO moiety, partially substituting hydrogen-bonding stabilizing water. Although this only results marginal barrier it creates local hydrophobic environment scarcity bonds owing great ionic radius, impeding surrounding oxygen adsorbed *CO. This skillfully circumvents further hydrogenation *CO C1 pathway, serving predominant factor facilitates coupling. study unveils comprehensive mechanism cation–water–adsorbate interactions that can facilitate optimization electrolyte EDL efficient CO2RR.

Язык: Английский

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Lattice Oxygen Redox Mechanisms in the Alkaline Oxygen Evolution Reaction

Advanced Functional Materials, Год журнала: 2024, Номер 34(32)

Опубликована: Март 25, 2024

Abstract Understanding of fundamental mechanism and kinetics the oxygen evolution reaction (OER) is pivotal for designing efficient OER electrocatalysts owing to its key role in electrochemical energy conversion devices. In past few years, lattice oxidation (LOM) arising from anodic redox chemistry has attracted significant attention as it involves a direct O─O coupling thus bypasses thermodynamic limitations traditional adsorbate (AEM). Transition metal‐based oxyhydroxides are generally acknowledged real catalytic phase alkaline media. particular, their low‐dimensional layered structures offer sufficient structural flexibility trigger LOM. Herein, comprehensive overview provided recent advances anion LOM‐based electrocatalysts. Based on analyses electronic structure LOM, strategy proposed activate Possible identification techniques corroboration also reviewed. addition, reconstruction process induced by LOM focused importance multiple situ/operando characterizations highlighted unveil chemical origins To conclude, prospect remaining challenges future opportunities presented.

Язык: Английский

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Hybridization State Transition under Working Conditions: Activity Origin of Single-Atom Catalysts

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(22), С. 15640 - 15647

Опубликована: Май 21, 2024

Single-atom catalysts (SACs) have been widely investigated and emerged as a transformative approach in electrocatalysis. Despite their clear structure, the origin of exceptional activity remains elusive. Herein, we elucidate common phenomenon hybridization state transition metal centers, which is responsible for across various SACs different reactions. Focusing on N-doped carbon-supported Ni SAC (NiN4 SAC) CO2 reduction reaction (CO2RR), our comprehensive computations successfully clarify under working conditions its relation with activity. This transition, triggered by intermediates applied potential, converts center from inert dsp2 to active d2sp3 state. Importantly, calculated selectivity CO2RR over d2sp3-hybridized are consistent experimental results, offering strong support proposed hypothesis. work suggests universal principle electronic structure evolution that could revolutionize catalyst design, also introduces new paradigm manipulating states enhance catalytic performance, implications reactions platforms.

Язык: Английский

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Activity versus stability of atomically dispersed transition-metal electrocatalysts

Nature Reviews Materials, Год журнала: 2024, Номер 9(9), С. 643 - 656

Опубликована: Июль 31, 2024

Язык: Английский

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Modeling Interfacial Dynamics on Single Atom Electrocatalysts: Explicit Solvation and Potential Dependence

Accounts of Chemical Research, Год журнала: 2024, Номер 57(2), С. 198 - 207

Опубликована: Янв. 3, 2024

ConspectusSingle atom electrocatalysts, with noble metal-free composition, maximal efficiency, and exceptional reactivity toward various energy environmental applications, have become a research hot spot in the recent decade. Their simplicity isolated nature of atomic structure their active site also made them an ideal model catalyst system for studying reaction mechanisms activity trends. However, state single sites during electrochemical reactions may not be as simple is usually assumed. To contrary, electrocatalysts been reported to under greater influence from interfacial dynamics, solvent electrolyte ions perpetually interacting electrified center applied electrode potential. These complexities render trends derived simplistic models dubious.In this Account, few popular electrocatalysis systems, we show how change potential induces nontrivial variation free profile elemental steps, demonstrate centers different electronic features can induce solvation structures at interface even same intermediate simplest reaction, discuss implication on kinetics thermodynamics better address selectivity We venture into more intriguing phenomena, such alternative pathways intermediates that are favored stabilized by polarization effects, long-range dynamics across region far beyond contact layer, dynamic activation or deactivation operation conditions. necessity including realistic aspects (explicit solvent, electrolyte, potential) correctly capture physics chemistry understand design principles fail they revised factors model. All these rich would remain hidden overlooked otherwise. believe complexity curse but blessing it enables deeper understanding finer control potential-dependent landscape reactions, which opens up new dimensions further optimization beyond. Limitations current methods challenges faced theoretical experimental communities discussed, along possible solutions awaiting development future.

Язык: Английский

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Emerging Atomistic Modeling Methods for Heterogeneous Electrocatalysis

Chemical Reviews, Год журнала: 2024, Номер 124(14), С. 8620 - 8656

Опубликована: Июль 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.

Язык: Английский

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Theoretical Prediction and Experimental Verification of IrO_x Supported on Titanium Nitride for Acidic Oxygen Evolution Reaction

Journal of the American Chemical Society, Год журнала: 2024, Номер 146(24), С. 16499 - 16510

Опубликована: Июнь 11, 2024

Reducing iridium (Ir) catalyst loading for acidic oxygen evolution reaction (OER) is a critical strategy large-scale hydrogen production via proton exchange membrane (PEM) water electrolysis. However, simultaneously achieving high activity, long-term stability, and reduced material cost remains challenging. To address this challenge, we develop framework by combining density functional theory (DFT) prediction using model surfaces proof-of-concept experimental verification thin films nanoparticles. DFT results predict that oxidized Ir monolayers over titanium nitride (IrOx/TiN) should display higher OER activity than IrOx while reducing loading. This verified depositing TiN physical vapor deposition. The promising film are then extended to commercially viable powder IrOx/TiN catalysts, which demonstrate lower overpotential mass commercial IrO2 stability of 250 h maintain current 10 mA cm–2. superior performance further confirmed electrolyzer (PEMWE), shows cell voltage achieve 1 A Both in situ X-ray absorption spectroscopy reveal the strongly depends on IrOx-TiN interaction direct Ir–Ti bonding. study highlights importance close between theoretical based mechanistic understanding catalysts facilitate development more practical with OER.

Язык: Английский

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Why Do Weak-Binding M–N–C Single-Atom Catalysts Possess Anomalously High Oxygen Reduction Activity?

Journal of the American Chemical Society, Год журнала: 2025, Номер unknown

Опубликована: Фев. 9, 2025

Single-atom catalysts (SACs) with metal–nitrogen–carbon (M–N–C) structures are widely recognized as promising candidates in oxygen reduction reactions (ORR). According to the classical Sabatier principle, optimal 3d metal catalysts, such Fe/Co–N–C, achieve superior catalytic performance due moderate binding strength. However, substantial ORR activity demonstrated by weakly M–N–C Ni/Cu–N–C challenges current understandings, emphasizing need explore new underlying mechanisms. In this work, we integrated a pH-field coupled microkinetic model detailed experimental electron state analyses verify novel key step reaction pathway of weak-binding SACs─the adsorption at metal–nitrogen bridge site. This significantly altered scaling relations, electric field responses, and solvation effects, further impacting kinetic barrier from HOO* O* pH-dependent performance. Synchrotron spectra analysis provides evidence for model, showing an increase density on antibonding π orbitals N atoms confirming presence N–O bonds. These findings redefine understanding catalyst behavior, opening up perspectives their application clean energy.

Язык: Английский

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The Impact of Electric Fields on Processes at Electrode Interfaces

Chemical Reviews, Год журнала: 2025, Номер unknown

Опубликована: Янв. 16, 2025

The application of external electric fields to influence chemical reactions at electrode interfaces has attracted considerable interest in recent years. However, the design achieve highly efficient and selective catalytic systems, akin optimized found enzyme active sites, remains a significant challenge. Consequently, there been substantial effort probing understanding interfacial electrode/electrolyte their effect on adsorbates. In this review, we examine advances experimental, computational, theoretical studies field, origin vibrational Stark adsorbates surfaces, effects interfaces. We also discuss control charge transfer using magnetic fields. Finally, outline perspectives key areas for future studies.

Язык: Английский

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Supramolecular Engineering of Vinylene‐Linked Covalent Organic Framework – Ruthenium Oxide Hybrids for Highly Active Proton Exchange Membrane Water Electrolysis

Advanced Materials, Год журнала: 2025, Номер unknown

Опубликована: Фев. 3, 2025

The controlled formation of a functional adlayer at the catalyst-water interface is highly challenging yet potentially powerful strategy to accelerate proton transfer and deprotonation for ultimately improving performance proton-exchange membrane water electrolysis (PEMWE). In this study, synthesis robust vinylene-linked covalent organic frameworks (COFs) possessing high conductivities reported, which are subsequently hybridized with ruthenium dioxide yielding high-performance anodic catalysts acidic oxygen evolution reaction (OER). situ spectroscopic measurements corroborated by theoretical calculations reveal that assembled hydrogen bonds formed between COFs adsorbed oxo-intermediates effectively orient interfacial molecules, stabilizing transition states intermediate OER. This determines decrease in energy barriers deprotonation, resulting exceptional OER performance. When integrated into PEMWE device, system achieves record current density 1.0 A cm-2 only 1.54 V cell voltage, long-term stability exceeding 180 h industrial-level 200 mA cm-2. approach relying on self-assembly an oriented hydrogen-bonded highlights disruptive potential customizable structures multifunctional sites advancing technologies.

Язык: Английский

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