Regulating electronic states of nitride/hydroxide to accelerate kinetics for oxygen evolution at large current density

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

Опубликована: Апрель 4, 2023

Rational design efficient transition metal-based electrocatalysts for oxygen evolution reaction (OER) is critical water splitting. However, industrial water-alkali electrolysis requires large current densities at low overpotentials, always limited by intrinsic activity. Herein, we report hierarchical bimetal nitride/hydroxide (NiMoN/NiFe LDH) array as model catalyst, regulating the electronic states and tracking relationship of structure-activity. As-activated NiMoN/NiFe LDH exhibits industrially required density 1000 mA cm-2 overpotential 266 mV with 250 h stability OER. Especially, in-situ electrochemical spectroscopic reveals that heterointerface facilitates dynamic structure to optimize structure. Operando impedance spectroscopy implies accelerated OER kinetics intermediate due fast charge transport. The mechanism revealed combination theoretical experimental studies, indicating as-activated follows lattice oxidation kinetics. This work paves an avenue develop catalysts via tuning states.

Язык: Английский

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Identification of the Origin for Reconstructed Active Sites on Oxyhydroxide for Oxygen Evolution Reaction

Advanced Materials, Год журнала: 2022, Номер 35(6)

Опубликована: Ноя. 21, 2022

The regulation of atomic and electronic structures active sites plays an important role in the rational design oxygen evolution reaction (OER) catalysts toward electrocatalytic hydrogen generation. However, precise identification for surface reconstruction behavior during OER remains elusive water-alkali electrolysis. Herein, irreversible accompanied by copper dynamic cobalt iron layered double hydroxide (CoFe LDH) precatalyst to form CoFeCuOOH species with high-valent Co is reported, identifying origin reconstructed through operando UV-Visible (UV-vis), situ Raman, X-ray absorption fine-structure (XAFS) spectroscopies. Density functional theory analysis rationalizes this typical structure causing transfer intramolecular electrons ligand holes, promoting sites. Specifically, unambiguous explored 18 O isotope-labeling differential electrochemical mass spectrometry (DEMS) supported theoretical calculation, confirming mechanism switch oxygen-vacancy-site (OVSM) pathway on lattice oxygen. This work enables elucidate vital active-site generation representative contribution OVSM efficient performance.

Язык: Английский

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Activating lattice oxygen in high-entropy LDH for robust and durable water oxidation

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

Опубликована: Сен. 27, 2023

The oxygen evolution reaction is known to be a kinetic bottleneck for water splitting. Triggering the lattice oxidation mechanism (LOM) can break theoretical limit of conventional adsorbate and enhance kinetics, yet unsatisfied stability remains grand challenge. Here, we report high-entropy MnFeCoNiCu layered double hydroxide decorated with Au single atoms O vacancies (AuSA-MnFeCoNiCu LDH), which not only displays low overpotential 213 mV at 10 mA cm-2 high mass activity 732.925 A g-1 250 in 1.0 M KOH, but also delivers good 700 h continuous operation ~100 cm-2. Combining advanced spectroscopic techniques density functional theory calculations, it demonstrated that synergistic interaction between incorporated leads an upshift 2p band weakens metal-O bond, thus triggering LOM, reducing energy barrier, boosting intrinsic activity.

Язык: Английский

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High-entropy alloys in electrocatalysis: from fundamentals to applications

Chemical Society Reviews, Год журнала: 2023, Номер 52(23), С. 8319 - 8373

Опубликована: Янв. 1, 2023

In this review, we provide a comprehensive summary of recent advances in the synthesis strategies, design principles, and characterization technologies high entropy alloys, their applications various electrocatalytic conversion reactions.

Язык: Английский

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Atomically dispersed Ru oxide catalyst with lattice oxygen participation for efficient acidic water oxidation

Chem, Год журнала: 2023, Номер 9(7), С. 1882 - 1896

Опубликована: Апрель 6, 2023

Язык: Английский

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Activating Lattice Oxygen in Spinel ZnCo₂O₄ through Filling Oxygen Vacancies with Fluorine for Electrocatalytic Oxygen Evolution

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(24)

Опубликована: Март 21, 2023

The development of productive catalysts for the oxygen evolution reaction (OER) remains a major challenge requiring significant progress in both mechanism and material design. Conventionally, thermodynamic barrier lattice oxidation (LOM) is lower than that absorbate (AEM) because former can overcome certain limitations. However, controlling OER pathway from AEM to LOM by exploiting intrinsic properties catalyst challenging. Herein, we incorporated F anions into vacancies spinel ZnCo2 O4 established link between electronic structure catalytic mechanism. Theoretical density calculations revealed upshifts O 2p center activates redox capability O, successfully triggering pathway. Moreover, high electronegativity favourable balancing residual protonation, which stabilize catalyst.

Язык: Английский

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Multicomponent transition metal oxides and (oxy)hydroxides for oxygen evolution

Nano Research, Год журнала: 2022, Номер 16(2), С. 1913 - 1966

Опубликована: Окт. 2, 2022

Язык: Английский

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Unlocking the Transition of Electrochemical Water Oxidation Mechanism Induced by Heteroatom Doping

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(40)

Опубликована: Авг. 15, 2023

Abstract Heteroatom doping has emerged as a highly effective strategy to enhance the activity of metal‐based electrocatalysts toward oxygen evolution reaction (OER). It is widely accepted that does not switch OER mechanism from adsorbate (AEM) lattice‐oxygen‐mediated (LOM), and enhanced attributed optimized binding energies intermediates. However, this seems inconsistent with fact overpotential doped (<300 mV) considerably smaller than limit AEM (>370 mV). To determine origin inconsistency, we select phosphorus (P)‐doped nickel‐iron mixed oxides model observe enhances covalency metal‐oxygen bonds drive pathway transition LOM, thereby breaking adsorption linear relation between *OH *OOH in AEM. Consequently, obtained P‐doped display small 237 mV at 10 mA cm −2 . Beyond P, similar also observed on sulfur doping. These findings offer new insights into substantially originating heteroatom

Язык: Английский

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High‐Entropy Catalyst—A Novel Platform for Electrochemical Water Splitting

Advanced Functional Materials, Год журнала: 2022, Номер 32(47)

Опубликована: Сен. 16, 2022

Abstract High‐entropy materials (HEMs) have been in the spotlight as emerging catalysts for electrochemical water splitting. In particular, HEM feature multi‐element active sites and unsaturated coordination well entropy stabilization comparison with their single‐element counterparts. Herein, a comprehensive overview of used splitting is provided, covering both hydrogen evolution reaction (HER) oxygen (OER). Particularly, review begins discussions concept structure HEMs. addition, effective strategies rationally designing HEMs on basis computational techniques experimental aspects described. Importantly, importance computationally aided methods, that is, density functional theory calculations, high‐throughput screening, machine learning, to discovery design HEMs, Furthermore, applications field electrolysis are reviewed. Eventually, an outlook regarding prospects future opportunities provided.

Язык: Английский

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Boosting Oxygen Evolution Reaction of (Fe,Ni)OOH via Defect Engineering for Anion Exchange Membrane Water Electrolysis Under Industrial Conditions

Advanced Materials, Год журнала: 2023, Номер 35(44)

Опубликована: Авг. 22, 2023

Developing non-precious catalysts with long-term catalytic durability and structural stability under industrial conditions is the key to practical alkaline anion exchange membrane (AEM) water electrolysis. Here, an energy-saving approach proposed synthesize defect-rich iron nickel oxyhydroxide for efficiency toward oxygen evolution reaction. Benefiting from in situ cation exchange, nanosheet-nanoflake-structured catalyst homogeneously embedded in, tightly bonded to, its substrate, making it ultrastable at high current densities. Experimental theoretical calculation results reveal that introduction of Ni FeOOH reduces activation energy barrier reaction purposely created defects not only ensure exposure active sites maximize effective surface but also modulate local coordination environment chemisorption properties both Fe sites, thus lowering *O *OOH. Consequently, optimized d-(Fe,Ni)OOH exhibits outstanding activity laboratory conditions. The large-area d-(Fe,Ni)OOH||NiMoN pair requires 1.795 V reach a density 500 mA cm-2 absolute 12.5 A AEM electrolyzer overall electrolysis, showing great potential

Язык: Английский

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