Tungstate Intercalated NiFe Layered Double Hydroxide Enables Long‐Term Alkaline Seawater Oxidation

Small, Journal Year: 2024, Volume and Issue: 20(28)

Published: Feb. 16, 2024

Abstract Renewable electricity‐driven seawater splitting presents a green, effective, and promising strategy for building hydrogen (H 2 )‐based energy systems (e.g., storing wind power as H ), especially in many coastal cities. The abundance of Cl − seawater, however, will cause severe corrosion anode catalyst during the electrolysis, thus affect long‐term stability catalyst. Herein, oxidation performances NiFe layered double hydroxides (LDH), classic oxygen (O ) evolution material, can be boosted by employing tungstate (WO 4 2– intercalated guest. Notably, insertion WO 2− to LDH layers upgrades reaction kinetics selectivity, attaining higher current densities with ≈100% O generation efficiency alkaline seawater. Moreover, after 350 h test at 1000 mA cm −2 , only trace active chlorine detected electrolyte. Additionally, follows lattice mechanism on .

Language: Английский

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Self-supported ultrathin NiMn-LDH nanosheets for highly active and robust urea oxidation

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 484, P. 149706 - 149706

Published: Feb. 17, 2024

Language: Английский

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Inhibiting Dissolution of Active Sites in 80 °C Alkaline Water Electrolysis by Oxyanion Engineering

Angewandte Chemie International Edition, Journal Year: 2024, Volume and Issue: 63(32)

Published: May 29, 2024

Abstract Commercial alkaline water electrolysers typically operate at 80 °C to minimize energy consumption. However, NiFe‐based catalysts, considered as one of the most promising candidates for anode, encounter bottleneck high solubility such temperatures. Herein, we discover that dissolution NiFe layered double hydroxides (NiFe‐LDH) during operation not only leads degradation anode itself, but also deactivates cathode splitting, resulting in decay overall electrocatalytic performance. Aiming suppress dissolution, employed oxyanions inhibitors electrolyte. The added phosphates electrolyte inhibit loss NiFe‐LDH active sites 400 mA cm −2 1/3 original amount, thus reducing rate performance by 25‐fold. Furthermore, usage borates, sulfates, and carbonates yields similar results, demonstrating reliability universality site inhibitor, its role elevated electrolysis.

Language: Английский

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Synergistic Atomic Environment Optimization of Nickel–Iron Dual Sites by Co Doping and Cr Vacancy for Electrocatalytic Oxygen Evolution

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 8, 2025

The dual-site synergistic catalytic mechanism on NiFeOOH suggests weak adsorption of Ni sites and strong Fe limited its activity toward alkaline oxygen evolution reaction (OER). Large-scale density functional theory (DFT) calculations confirm that Co doping can increase adsorption, while the metal vacancy reduce adsorption. combined two factors further modulate atomic environment optimize free energy oxygen-containing intermediates, thus enhancing OER activity. Accordingly, we used Cr vacancies to fabricate an amorphous catalyst VCr,Co-NiFeOOH. It provides overpotential 239 mV at 100 mA cm–2 high stability over 500 h with a ∼98% potential retention. resulting water electrolyzer based anion exchange membrane (AEM) exhibits remarkable performance 1 A 1.68 V in M KOH. XPS, soft-XAS, XANES Bader charge analysis results reveal regulation local microenvironment valence state by doping, improving sites. alleviate DFT effect redistribute Ni/Fe sites, d-band center Fe, endow Ni–Fe dual barrier rate-determining step.

Language: Английский

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Cation–anion modification and heterostructure for cooperative regulation of electron distribution in NiMoS/NiFeMn-LDH electrocatalyst to enhance water splitting

Journal of Colloid and Interface Science, Journal Year: 2025, Volume and Issue: 688, P. 106 - 117

Published: Feb. 21, 2025

Language: Английский

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Accelerating the Transformation of Active β‐NiOOH on NiFe Layered Double Hydroxide via Cation–anion Collaborative Coordination for Alkaline Water Oxidation at High Current Densities

Advanced Functional Materials, Journal Year: 2025, Volume and Issue: unknown

Published: April 7, 2025

Abstract The NiFe‐based layered double hydroxides (LDH) undergo surface reconstruction, generating metal hydroxyl oxides that act as active species during the alkaline oxygen evolution reaction (OER). However, sluggish reconstruction process and excessive oxidation at higher anodic potentials frustrate OER activity stability. Herein, a cation–anion collaborative coordination strategy is harnessed to build (Ni, Fe)─S─Zn structures in NiFe LDH on nickel foam (S‐NiFeZn LDH/NF), which lowers energy barrier aids forming highly β‐NiOOH process. Meanwhile, also optimize adsorption of oxygen‐containing intermediates, enhancing kinetics. As result, S‐NiFeZn LDH/NF achieves low overpotentials 201 mV 10 mA cm −2 293 500 1.0 m KOH. Moreover, cell assembled with anode commercial NiMo cathode demonstrates excellent overall water splitting activity, voltages 1.62 1.81 V KOH, exhibits ultralong‐term durability over h , even operating stably for 200 an electrolyzer under industrial conditions (30% KOH 80 °C).

Language: Английский

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Strongly Coupled NiMo@Alloy‐LDH Interfaces with Low‐Barrier Schottky Junctions for Oxygen Evolution Reaction

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(51)

Published: Aug. 27, 2024

Abstract The main challenge in developing Schottky‐contact OER catalytic devices based on layered double hydroxides (LDHs) is to achieve metal–semiconductor junctions with low contact resistance and high charge transfer capacity. However, due the presence of potential barriers Fermi pinning, conventional Schottky contacts are usually unsatisfactory, resulting poor‐working electrode performance energy consumption. In this study, a new concept “hindrance factor” introduced quantify difficulty electron transfer, low‐hindrance factor formed by strong coupling semiconductor LDH NiMo alloy clusters designed. This interface guides redistribution, optimizes bonding orbital states adsorption sites, enhances targeted OH intermediates. results show that configured NiMo@NiFeCe‐LDH working only needs 1.445 V (vs RHE) drive reaction shows excellent durability 400 h testing. At same time, strategy for screening high‐performance developed. provides bridge studying properties, hybridization, reveals mechanism reducing resistance, has important guiding significance electrocatalysts stability.

Language: Английский

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Boosting Oxygen Evolution Reaction Performance on NiFe-Based Catalysts Through d-Orbital Hybridization

Nano-Micro Letters, Journal Year: 2024, Volume and Issue: 17(1)

Published: Sept. 26, 2024

Abstract Anion-exchange membrane water electrolyzers (AEMWEs) for green hydrogen production have received intensive attention due to their feasibility of using earth-abundant NiFe-based catalysts. By introducing a third metal into catalysts construct asymmetrical M-NiFe units, the d -orbital and electronic structures can be adjusted, which is an important strategy achieve sufficient oxygen evolution reaction (OER) performance in AEMWEs. Herein, ternary NiFeM (M: La, Mo) featured with distinct units varying -orbitals are reported this work. Experimental theoretical calculation results reveal that doping La leads optimized hybridization between orbital 2 p oxygen, resulting enhanced adsorption strength intermediates, reduced rate-determining step energy barrier, responsible OER performance. More critically, obtained NiFeLa catalyst only requires 1.58 V reach 1 A cm −2 anion exchange electrolyzer demonstrates excellent long-term stability up 600 h.

Language: Английский

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p–d Orbitals Coupling Heterosites of Ni₂P/NiFe‐LDH Interface Enable O─H Cleavage for Water Splitting

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(40)

Published: Aug. 11, 2024

Abstract Electrocatalytic water splitting for hydrogen production still faces a bottleneck due to sluggish reactive kinetics and high energy barriers. Herein, p–d orbital coupling P–Fe heterosites are constructed at Ni 2 P–FeNi‐LDH interfaces enhance the O─H bond cleavage of reaction intermediates H O* OH* oxygen evolution (OER) (HER), respectively. The P/NiFe‐LDH heterostructure shows superior HER OER activities alkaline with overpotentials 230 270 mV 100 mA cm −2 , respectively, even exhibits activity electrocatalytic seawater splitting. interaction P 2p Fe 3d orbitals upshifts d‐band center downshifts p‐band P. This finding not only facilitates dissociation bonds in O promotes Volmer–Heyrovsky step HER, but also reduces barrier rate‐determining from transition. work proposes new approach constructing heterojunctions facilitate reduce electrocatalysis.

Language: Английский

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NiFe‐Based Electrocatalysts for Alkaline Oxygen Evolution: Challenges, Strategies, and Advances Toward Industrial‐Scale Deployment

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 2, 2024

Abstract Developing high‐efficiency alkaline water splitting technology holds great promise in potentially revolutionizing the traditional petrochemical industry to a more sustainable hydrogen economy. Importantly, oxygen evolution reaction (OER) accompanied at anode is considered as critical bottleneck terms of both complicated mechanism and sluggish kinetics, requiring rational design OER electrocatalysts elucidate structure‐performance relationship reduce applied overpotential. As benchmarked non‐precious metal candidate, NiFe‐based have gained enormous attention due low‐cost, earth‐abundance, remarkable intrinsic activity, which are expected be implemented industrial splitting. In this contribution, comprehensive overview provided, starting with fundamental mechanisms, evaluation metrics, synthetic protocols. Subsequently, basic principles corresponding regulatory strategies summarized following sequence substrate‐catalyst‐electrolyte efficient robust toward industrial‐scale deployment. Perspectives on remaining challenges instructive opportunities booming field finally discussed.

Language: Английский

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