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

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: April 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.

Language: Английский

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Surface Reconstruction of Water Splitting Electrocatalysts

Advanced Energy Materials, Journal Year: 2022, Volume and Issue: 12(33)

Published: July 8, 2022

Abstract Water electrolysis is regarded as an efficient and green method to produce hydrogen gas, a clean energy carrier that holds the key solving global problems. So far, efficiency large‐scale application of water are restricted by electrocatalytic activity applied catalysts. Recently, reconstruction phenomenon electrocatalysts during catalytic reaction has been discovered, which could form reactive sites for both oxygen evolution reactions. Regulation process generate large number species with high since demonstrated effective strategy enhance performance electrocatalysts. This review summarizes recent progress in regulation strategies First, mechanism briefly introduced, critical factors regarding systematically discussed, followed brief introduction advanced characterization reconstruction. Moreover, modulation summarized reported examples highlighting promoted effects on process. Finally, challenges facing surface‐reconstructed catalysts future discussed.

Language: Английский

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Synergistic effect of multiple vacancies to induce lattice oxygen redox in NiFe-layered double hydroxide OER catalysts

Applied Catalysis B Environment and Energy, Journal Year: 2022, Volume and Issue: 323, P. 122091 - 122091

Published: Nov. 3, 2022

Language: Английский

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Key components and design strategy of the membrane electrode assembly for alkaline water electrolysis

Energy & Environmental Science, Journal Year: 2023, Volume and Issue: 16(4), P. 1384 - 1430

Published: Jan. 1, 2023

This review presents the state-of-the-art MEAs, including key components and preparation technologies. Especially, overall design strategies of MEAs are discussed to promote high-performance alkaline water electrolysis.

Language: Английский

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Cation Defect Engineering of Transition Metal Electrocatalysts for Oxygen Evolution Reaction

Advanced Energy Materials, Journal Year: 2022, Volume and Issue: 12(45)

Published: Sept. 30, 2022

Abstract The rational design and development of highly efficient oxygen evolution reaction (OER) electrocatalysts is vital for the application renewable energy devices. Recently, strategy defect engineering draws much attention due to its positive effect on regulating electronic structure, thus, promoting electrocatalytic performance various materials. In this review, main focus cation vacancy defects transition metal‐based electrocatalysts; latest progress in OER summarized. different effects are well discussed together with mechanism, mainly including improving conductivity, optimizing adsorption key intermediates, guiding surface reconstruction form active species, enhancing long‐term stability. Then, methods construct characterization vacancies systematically introduced. Finally, remaining challenges future prospects further proposed.

Language: Английский

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Lattice‐Strain Engineering for Heterogenous Electrocatalytic Oxygen Evolution Reaction

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(39)

Published: Jan. 14, 2023

Abstract The energy efficiency of metal–air batteries and water‐splitting techniques is severely constrained by multiple electronic transfers in the heterogenous oxygen evolution reaction (OER), high overpotential induced sluggish kinetics has become an uppermost scientific challenge. Numerous attempts are devoted to enabling activity, selectivity, stability via tailoring surface physicochemical properties nanocatalysts. Lattice‐strain engineering as a cutting‐edge method for tuning geometric configuration metal sites plays pivotal role regulating interaction catalytic surfaces with adsorbate molecules. By defining d‐band center descriptor structure–activity relationship, individual contribution strain effects within state‐of‐the‐art electrocatalysts can be systematically elucidated OER optimization mechanism. In this review, fundamentals advancements strain‐catalysts showcased innovative trigger strategies enumerated, particular emphasis on feedback mechanism between precise regulation lattice‐strain optimal activity. Subsequently, modulation various attributes categorized impediments encountered practicalization strained effect discussed, ending outlook future research directions burgeoning field.

Language: Английский

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Recent advances in interface engineering strategy for highly‐efficient electrocatalytic water splitting

InfoMat, Journal Year: 2022, Volume and Issue: 5(1)

Published: Oct. 13, 2022

Abstract The hydrogen energy generated by the electrocatalytic water splitting reaction has been established as a renewable and clean carrier with ultra‐high density, which can well make up for shortcomings of conventional sources, such geographical limitations, climatic dependence, wastage. Notably, introduction electrocatalysts enhance efficiency process to generate hydrogen. Particularly, heterostructure constructed coupling multiple components (or phases) have emerged most promising option due well‐known electronic synergistic effects. existing reviews on interface engineering electrocatalyst design mostly focus relationship between heterostructures specific reactions. However, comprehensive overview integration model building, directional synthesis, mechanism rarely reported. To this end, in review, development catalysts is systematically introduced from perspective classification, growth regulation performance based interfacial microenvironment (bonding, configuration, lattice strain, etc.), thereby offering useful insights construction models. Besides, combined current applications strategies, challenges future are discussed relevant solutions proposed. Overall, review serve theoretical reference mechanism, further promote production technologies low consumption high yield. image

Language: Английский

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Unraveling a bifunctional mechanism for methanol-to-formate electro-oxidation on nickel-based hydroxides

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: March 27, 2023

For nickel-based catalysts, in-situ formed nickel oxyhydroxide has been generally believed as the origin for anodic biomass electro-oxidations. However, rationally understanding catalytic mechanism still remains challenging. In this work, we demonstrate that NiMn hydroxide catalyst can enable methanol-to-formate electro-oxidation reaction (MOR) with a low cell-potential of 1.33/1.41 V at 10/100 mA cm-2, Faradaic efficiency nearly 100% and good durability in alkaline media, remarkably outperforming NiFe hydroxide. Based on combined experimental computational study, propose cyclic pathway consists reversible redox transitions NiII-(OH)2/NiIII-OOH concomitant MOR. More importantly, it is proved NiIII-OOH provides active sites including NiIII nearby electrophilic oxygen species, which work cooperative manner to promote either spontaneous or non-spontaneous MOR process. Such bifunctional well account not only highly selective formate formation but also transient presence NiIII-OOH. The different activities hydroxides be attributed their oxidation behaviors. Thus, our clear rational overall hydroxides, beneficial advanced design.

Language: Английский

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Oxygen‐Rich Cobalt–Nitrogen–Carbon Porous Nanosheets for Bifunctional Oxygen Electrocatalysis

Advanced Functional Materials, Journal Year: 2022, Volume and Issue: 32(23)

Published: March 4, 2022

Abstract Metal–nitrogen–carbon (M–N–C) materials have attracted much interest in bifunctional oxygen‐involving electrocatalysis for rechargeable Zn–air batteries. Such M–N–C electrocatalysts with M–N x sites show good activity the oxygen reduction reaction (ORR) but moderate evolution (OER). Herein, an oxygen‐rich material (O–Co–N/C) a highly porous nanosheet structure is reported as electrocatalyst, which prepared by direct pyrolysis of ultrathin CoO nanosheets decorated zeolitic imidazolate framework‐8 nanoparticles under inert atmosphere. Particularly, Co O–Co–N/C electrocatalyst contain both Co–N and Co–O coordination environments to provide intrinsic active ORR OER, respectively. Furthermore, electrochemical studies that catalyst retains comparable common half‐wave potential 0.85 V vs reversible hydrogen electrode better OER overpotential 0.29 at current density 10 mA cm −2 . This study provides insights into development effective metal centers coordinated nitrogen atoms.

Language: Английский

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Defect Engineered Metal–Organic Framework with Accelerated Structural Transformation for Efficient Oxygen Evolution Reaction

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(43)

Published: Sept. 6, 2023

Metal-organic frameworks (MOFs) have been increasingly applied in oxygen evolution reaction (OER), and the surface of MOFs usually undergoes structural transformation to form metal oxyhydroxides serve as catalytically active sites. However, controllable regulation reconstruction process remains a great challenge. Here we report defect engineering strategy facilitate during OER with enhanced activity. Defective (denoted NiFc'x Fc1-x ) abundant unsaturated sites are constructed by mixing ligands 1,1'-ferrocene dicarboxylic acid (Fc') defective ferrocene carboxylic (Fc). series more prone be transformed compared non-defective (NiFc'). Moreover, as-formed derived from contain vacancies. NiFc'Fc grown on nickel foam exhibits excellent catalytic activity an overpotential 213 mV at current density 100 mA cm-2 , superior that undefective NiFc'. Experimental results theoretical calculations suggest vacancies adsorption oxygen-containing intermediates centers, thus significantly improving

Language: Английский

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