Recent Advances in Design of Electrocatalysts for High‐Current‐Density Water Splitting

Advanced Materials, Journal Year: 2021, Volume and Issue: 34(16)

Published: Dec. 4, 2021

Abstract Electrochemical water splitting technology for producing “green hydrogen” is important the global mission of carbon neutrality. Electrocatalysts with decent performance at high current densities play a central role in industrial implementation this technology. This field has advanced immensely recent years, as witnessed by many types catalysts designed and synthesized toward industriallyrelevant (>200 mA cm –2 ). By discussing advances field, several key aspects are summarized that affect catalytic high‐current‐density electrocatalysis, including dimensionality catalysts, surface chemistry, electron transport path, morphology, catalyst‐electrolyte interplay. The multiscale design strategy considers these comprehensively developing electrocatalysts highlighted. perspectives on future directions emerging also put forward.

Language: Английский

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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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Transition metal-based catalysts for electrochemical water splitting at high current density: current status and perspectives

Nanoscale, Journal Year: 2021, Volume and Issue: 13(30), P. 12788 - 12817

Published: Jan. 1, 2021

Current popular transition metal-based electrocatalysts developed for HER/OER in water splitting at high current density are critically reviewed and discussed.

Language: Английский

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Surface Activation and Ni‐S Stabilization in NiO/NiS₂for Efficient Oxygen Evolution Reaction

Angewandte Chemie International Edition, Journal Year: 2022, Volume and Issue: 61(35)

Published: June 22, 2022

Manipulating the active species and improving structural stabilization of sulfur-containing catalysts during OER process remain a tremendous challenge. Herein, we constructed NiO/NiS2 Fe-NiO/NiS2 as catalyst models to study effect Fe doping. As expected, exhibits low overpotential 270 mV at 10 mA cm-2 . The accumulation hydroxyl groups on surface materials after doping can promote formation highly NiOOH lower potential. Moreover, investigated level corrosion M-S bonds compared stability variation with different locations. Interestingly, bonded S in bulk sacrificial agent alleviate oxidation partial Ni-S thus endow long-term durability. This work could motivate community focus more resolving materials.

Language: Английский

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A review of Ni based powder catalyst for urea oxidation in assisting water splitting reaction

Advanced Powder Materials, Journal Year: 2022, Volume and Issue: 1(3), P. 100030 - 100030

Published: Jan. 10, 2022

Water splitting has been regarded as a sustainable and environmentally-friendly technique to realize green hydrogen generation, while more energy is consumed due the high overpotentials required for anode oxygen evolution reaction. Urea electrooxidation, an ideal substitute, thus received increasing attention in assisting water-splitting reactions. Note that highly efficient catalysts are still drive urea oxidation, facile generation of valence state species significant reaction based on electrochemical-chemical mechanisms. The cost rareness make noble metal impossible further consideration large-scale application. Ni-based very promising their cheap price, structure tuning, good compatibility, easy active phase formation. In light advances made recently, herein, we reviewed recent powder oxidation fundamental firstly presented clarify mechanism urea-assisted water splitting, then prevailing evaluation indicators briefly expressed electrochemical measurements. catalyst design principle including synergistic effect, electronic defect construction surface reconstruction well main fabrication approaches various assisted summarized discussed. problems challenges also concluded fabrication, performance evaluation, Considering key influencing factors catalytic process application, should be given structure−property relationship deciphering, novel development real device; specifically, effort directed with multi-functions simultaneously promote steps anti-corrosion ability by revealing local integration practical We believe current summarization will instructive helpful understanding action via technique.

Language: Английский

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Constructing Built‐in Electric Field in Heterogeneous Nanowire Arrays for Efficient Overall Water Electrolysis

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(26)

Published: April 13, 2023

Efficient bifunctional electrocatalysts for hydrogen and oxygen evolution reactions are key to water electrolysis. Herein, we report a built-in electric field (BEF) strategy fabricate heterogeneous nickel phosphide-cobalt nanowire arrays grown on carbon fiber paper (Ni2 P-CoCH/CFP) with large work function difference (ΔΦ) as overall splitting. Impressively, Ni2 P-CoCH/CFP exhibits remarkable catalytic activity obtain 10 mA cm-2 , respectively. Moreover, the assembled lab-scale electrolyzer driven by an AAA battery delivers excellent stability after 50 h electrocatalysis 100 % faradic efficiency. Computational calculations combining experiments reveal interface-induced effect facilitates asymmetrical charge distributions, thereby regulating adsorption/desorption of intermediates during reactions. This offers avenue rationally design high-performance electrocatalysts.

Language: Английский

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Gd-induced electronic structure engineering of a NiFe-layered double hydroxide for efficient oxygen evolution

Journal of Materials Chemistry A, Journal Year: 2021, Volume and Issue: 9(5), P. 2999 - 3006

Published: Jan. 1, 2021

A novel rare earth hybrid electrocatalyst, consisting of a gadolinium-doped hierarchal NiFe-layered double hydroxide, is developed for improving the OER activity.

Language: Английский

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Interfacial Engineering of Ni₃N/Mo₂N Heterojunctions for Urea-Assisted Hydrogen Evolution Reaction

ACS Catalysis, Journal Year: 2023, Volume and Issue: 13(7), P. 4091 - 4100

Published: March 9, 2023

The urea oxidation reaction (UOR) is considered as an alternative to the oxygen evolution for high-efficiency hydrogen production. However, molecule relatively complex, containing both electron-donating amino (−NH2) and electron-withdrawing carbonyl (C═O) groups, understanding influence of different functional groups on adsorption behavior conducive rational design preparation high-performance UOR catalysts. Herein, we report a simple synthesis Ni3N/Mo2N heterostructure systematic investigation urea-assisted electrolytic Both temperature-programmed desorption theoretical calculations decipher that −NH2 C═O are more easily adsorbed Ni3N Mo2N, respectively. Meanwhile, could combine enhance advantages individual components, optimizing urea. Besides, this also beneficial improving performance. As expected, in two-electrode water electrolyzer utilizing bifunctional catalysts, production can readily occur at evidently lower voltage (1.36 V@10 mA cm–2), which much than traditional electrolysis, well 7 times higher rate achieved.

Language: Английский

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N-Doped Graphene-Decorated NiCo Alloy Coupled with Mesoporous NiCoMoO Nano-sheet Heterojunction for Enhanced Water Electrolysis Activity at High Current Density

Nano-Micro Letters, Journal Year: 2021, Volume and Issue: 13(1)

Published: Feb. 19, 2021

Developing highly effective and stable non-noble metal-based bifunctional catalyst working at high current density is an urgent issue for water electrolysis (WE). Herein, we prepare the N-doped graphene-decorated NiCo alloy coupled with mesoporous NiCoMoO nano-sheet grown on 3D nickel foam (NiCo@C-NiCoMoO/NF) splitting. NiCo@C-NiCoMoO/NF exhibits outstanding activity low overpotentials hydrogen oxygen evolution reaction (HER: 39/266 mV; OER: 260/390 mV) ± 10 1000 mA cm

Language: Английский

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Uncovering the Promotion of CeO₂/CoS_1.97 Heterostructure with Specific Spatial Architectures on Oxygen Evolution Reaction

Advanced Materials, Journal Year: 2021, Volume and Issue: 33(42)

Published: Sept. 3, 2021

Structural engineering and compositional controlling are extensively applied in rationally designing fabricating advanced freestanding electrocatalysts. The key relationship between the spatial distribution of components enhanced electrocatalysis performance still needs further elaborate elucidation. Here, CeO2 substrate supported CoS1.97 (CeO2 -CoS1.97 ) with surface decorated (CoS1.97 -CeO2 materials constructed to comprehensively investigate origin architectures for oxygen evolution reaction (OER). exhibits a low overpotential 264 mV at 10 mA cm-2 due stable heterostructure faster mass transfer. Meanwhile, has smaller Tafel slope 49 dec-1 through adsorption OH- , fast electron transfer, situ formation Co(IV)O2 species under OER condition. Furthermore, operando spectroscopic characterizations combined theoretical calculations demonstrate that play distinguished role modulating electronic structure promoting reconstruction from sulfide oxyhydroxide toward higher chemical valence. findings highlight electrocatalytic materials.

Language: Английский

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