Elucidating electrochemical nitrate and nitrite reduction over atomically-dispersed transition metal sites

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Июль 28, 2023

Electrocatalytic reduction of waste nitrates (NO3-) enables the synthesis ammonia (NH3) in a carbon neutral and decentralized manner. Atomically dispersed metal-nitrogen-carbon (M-N-C) catalysts demonstrate high catalytic activity uniquely favor mono-nitrogen products. However, reaction fundamentals remain largely underexplored. Herein, we report set 14; 3d-, 4d-, 5d- f-block M-N-C catalysts. The selectivity NO3- to NH3 media, with specific focus on deciphering role NO2- intermediate cascade, reveals strong correlations (R=0.9) between for NH3. Moreover, theoretical computations reveal associative/dissociative adsorption pathways evolution, over normal M-N4 sites their oxo-form (O-M-N4) oxyphilic metals. This work provides platform designing multi-element NO3RR cascades single-atom or hybridization extended surfaces.

Язык: Английский

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Modeling Single‐Atom Catalysis

Advanced Materials, Год журнала: 2023, Номер 35(46)

Опубликована: Сен. 25, 2023

Electronic structure calculations represent an essential complement of experiments to characterize single-atom catalysts (SACs), consisting isolated metal atoms stabilized on a support, but also predict new catalysts. However, simulating SACs with quantum chemistry approaches is not as simple often assumed. In this work, the factors that reliable simulation activity are examined. The Perspective focuses importance precise atomistic characterization active site, since even small changes in atom's surroundings can result large reactivity. dynamical behavior and stability under working conditions, well adopting appropriate methods solve Schrödinger equation for quantitative evaluation reaction energies addressed. relevance model adopted. For electrocatalysis must include effects solvent, presence electrolytes, pH, external potential. Finally, it discussed how similarities between coordination compounds may intermediates usually observed electrodes. When these aspects adequately considered, predictive power electronic quite limited.

Язык: Английский

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Predicting the Stability of Single-Atom Catalysts in Electrochemical Reactions

ACS Catalysis, Год журнала: 2023, Номер 14(1), С. 45 - 55

Опубликована: Дек. 9, 2023

The attention toward single-atom catalysts (SACs) for electrochemical processes is growing at an impressive pace. Electronic structure calculations play important role in this race by providing proposals of potentially relevant based on screening studies or the identification descriptors chemical activity. So far, almost all these predictions ignore a crucial aspect design catalyst: its stability. We propose simple yet general first-principles approach to predict stability SACs under working conditions pH and applied voltage. This construction thermodynamic cycle, where part information taken from experiment rest density functional theory (DFT) calculations. In particular, we make use formalism Pourbaix diagrams investigate reductive oxidative identify those that show pronounced tendency dissolve form other species. Applying procedure four transition metal atoms, Cr, Mn, Fe, Co, three supports, N-doped graphene, carbon nitride, covalent organic frameworks, key factor determining final binding energy free atom support. results several very good reactions are, fact, dramatically prone dissolution transformation species, suggesting every prediction SAC's catalytic activity should be accompanied parallel investigation

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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Density functional theory methods applied to homogeneous and heterogeneous catalysis: a short review and a practical user guide

Physical Chemistry Chemical Physics, Год журнала: 2024, Номер 26(10), С. 7950 - 7970

Опубликована: Янв. 1, 2024

The application of density functional theory (DFT) methods in catalysis has been growing fast the last few decades thanks to both availability more powerful high computing resources and development new efficient approximations approaches. DFT calculations allow for understanding crucial catalytic aspects that are difficult or even impossible access by experiments, thus contributing faster selective catalysts. Depending on system properties under investigation, different approaches should be used. Moreover, reliability obtained results deeply depends involved selected method model. This review addresses chemists, physicists materials scientists whose interest deals with DFT-based computational tools homogeneous heterogeneous catalysis. First, a brief introduction is presented. Then, main based atomic centered basis sets plane waves discussed, underlining differences, advantages limitations. Eventually, guidance towards selection model given, final focus evaluation energy barriers, which represents step all processes. Overall, rational practical guide beginners experienced users wide field

Язык: Английский

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Perspectives on the development of highly active, stable, and cost‐effective OER electrocatalysts in acid

Battery energy, Год журнала: 2023, Номер 2(5)

Опубликована: Авг. 21, 2023

Abstract Polymer electrolyte membrane water electrolysis (PEMWE) is an attractive hydrogen energy production technology that offers various advantages such as compact design, high operating pressure, current densities, and gas purity. However, PEMWE still faces several critical challenges, particularly with respect to the oxygen evolution reaction (OER) at anode. Highly active, corrosion‐resistant electrocatalytic materials are required for acidic OER owing its sluggish kinetics involving four‐electron transfer under harsh anodic potentials. To date, IrO 2 ‐ or RuO ‐based noble metal electrocatalysts have been employed commercial PEMWE. they remain inadequate in terms of satisfying industrial activity/stability‐related requirements. Above all, two metals too rare expensive, which significantly inhibits widespread commercialization Therefore, low‐cost, highly stable can operate media must be urgently developed. This review paper presents state‐of‐the‐art strategies address aforementioned issues by classifying them according objectives improving activity, enhancing stability, reducing cost. Then, finally, we summarize major tasks overcome put forward a few this field.

Язык: Английский

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Pt Single Atoms Supported on Defect Ceria as an Active and Stable Dual-Site Catalyst for Alkaline Hydrogen Evolution

Nano Letters, Год журнала: 2024, Номер 24(4), С. 1261 - 1267

Опубликована: Янв. 19, 2024

This work evaluates the feasibility of alkaline hydrogen evolution reaction (HER) using Pt single-atoms (1.0 wt %) on defect-rich ceria (Pt

Язык: Английский

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Theoretical Insights on the Charge State and Bifunctional OER/ORR Electrocatalyst Activity in 4d-Transition-Metal-Doped g-C₃N₄ Monolayers

ACS Applied Materials & Interfaces, Год журнала: 2024, Номер 16(5), С. 5779 - 5791

Опубликована: Янв. 25, 2024

Exploring efficient and stable electrocatalysts for the bifunctional oxygen evolution reaction (OER) reduction (ORR) is vital to developing renewable energy technologies. However, due substantial intricate design space associated with these OER/ORR electrocatalysts, their development presents a formidable challenge, resulting in cost-prohibitive nature both experimental computational studies. Herein, using defect physics method, we systematically investigate formation energies overpotential (ηBi) of 4d-transition-metal (4d-TM, 4d-TM = Zr, Nb, Mo, Ru, Rh, Pd, Ag)-doped monolayer supercell g-C3N4 (4d-TM@C54N72) based on density functional theory (DFT) calculations. Under N-rich C-rich conditions, find that RhN@C54N71 (Rh occupation N) PdN@C54N71 (Pd are smaller than other 4d-TMN@C54N71 (4d-TM N site); 4d-TMint@C54N72 interstitial site occupation), lowest-formation defects Pdint@C54N72. These results indicate they have better stabilities. Interestingly, lower systems, Pd0int@C54N72 (ηBi 1.00 V) Rh1+N@C54N71 0.73 ultralow can be great candidates electrocatalysts. We reason adjusting charge states 4d-TM@C54N72 tune interaction strength between oxygenated intermediates 4d-TM@C54N72, which plays crucial role activity reactions. Additionally, data obtained through machine learning (ML) application suggest electronegativity (Nm) bond length coordination atoms (dTM-OOH) primary descriptors characterizing OER ORR activities, respectively. The charged tuning would enable electrocatalytic performance optimization potential applications.

Язык: Английский

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CO₂ electroreduction on single atom catalysts: the role of the DFT functional

Physical Chemistry Chemical Physics, Год журнала: 2024, Номер 26(14), С. 10746 - 10756

Опубликована: Янв. 1, 2024

Impact of the adopted DFT functional on activation CO 2 a set single-atom catalysts.

Язык: Английский

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Four Generations of Volcano Plots for the Oxygen Evolution Reaction: Beyond Proton-Coupled Electron Transfer Steps?

Accounts of Chemical Research, Год журнала: 2024, Номер 57(9), С. 1336 - 1345

Опубликована: Апрель 15, 2024

ConspectusDue to its importance for electrolyzers or metal–air batteries energy conversion storage, there is huge interest in the development of high-performance materials oxygen evolution reaction (OER). Theoretical investigations have aided search active material motifs through construction volcano plots kinetically sluggish OER, which involves transfer four proton–electron pairs form a single molecule. The theory-driven approach has gained unprecedented popularity catalysis and communities, largely due simplicity, as adsorption free energies can be used approximate electrocatalytic activity by heuristic descriptors.In last two decades, binding-energy-based method witnessed renaissance with special concepts being developed incorporate missing factors into analysis. To this end, Account summarizes discusses different generations example OER. While first-generation methods relied on assessment thermodynamic information OER intermediates means scaling relations, second third strategies include overpotential kinetic effects analysis trends. Finally, fourth generation approaches allowed incorporation various mechanistic pathways methodology, thus paving path toward data- mechanistic-driven electrocatalysis.Although concept been significantly expanded recent years, further research activities are discussed challenging one main paradigms concept. date, evaluation trends relies assumption proton-coupled electron steps (CPET), even though experimental evidence sequential (SPET) steps. computational SPET solid-state electrodes ambitious, it strongly suggested comprehend their storage processes, including This achieved knowledge from homogeneous heterogeneous electrocatalysis focusing class single-atom catalysts center well defined. derived how analyze over could shape our understanding at electrified solid/liquid interfaces, crucial progress sustainable climate neutrality.

Язык: Английский

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