Surface reconstruction of Se-doped NiS2 enables high-efficiency oxygen evolution reaction

Journal of Energy Chemistry, Journal Year: 2023, Volume and Issue: 84, P. 173 - 180

Published: May 22, 2023

Language: Английский

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Linker Defects in Metal–Organic Frameworks for the Construction of Interfacial Dual Metal Sites with High Oxygen Evolution Activity

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(25)

Published: March 4, 2023

Abstract Designing efficient electrocatalysts based on metal–organic framework (MOF) nanosheet arrays (MOFNAs) with controlled active heterointerface for the oxygen evolution reaction (OER) is greatly desired yet challenging. Herein, a facile strategy synthesis of MOF‐based (γ‐FeOOH/Ni‐MOFNA) developed abundant heterointerfaces between Ni‐MOF and γ‐FeOOH nanosheets by introducing linker defects to former. The experimental theoretical results show key role in inducing growth secondary onto surface Ni‐MOFNAs, which further leads formation interfacial Ni/Fe dual sites high activity. Notably, resulting γ‐FeOOH/Ni‐MOFNA exhibits excellent OER performance low overpotentials 193 222 mV at 10 100 mA cm −2 , respectively. Furthermore, study structure–performance relationship heterostructures reveals that Ni interface have higher activity than those NiFe layered double hydroxide Ni‐MOFNA. This provides new prospect heterostructured highly enhanced OER.

Language: Английский

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Correlating Structural Disorder in Metal (Oxy)hydroxides and Catalytic Activity in Electrocatalytic Oxygen Evolution

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 63(7)

Published: Dec. 1, 2023

Abstract Understanding the correlation between structural evolution of electrocatalysts and their catalytic activity is both essential challenging. In this study, we investigate in context oxygen reaction (OER) by examining influence disorder during after dynamic on OER Fe−Ni (oxy)hydroxide catalysts using operando X‐ray absorption spectroscopy, alongside other experiments theoretical calculations. The Debye–Waller factors obtained from extended fine structure analyses reflect degree exhibit a robust with intrinsic activities electrocatalysts. enhanced situ‐generated metal (oxy)hydroxides derived different pre‐catalysts linked to increased disorder, offering promising approach for designing efficient This strategy may inspire similar investigations related electrocatalytic energy‐conversion systems.

Language: Английский

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Rare-Earth-Modified NiS₂ Improves OH Coverage for an Industrial Alkaline Water Electrolyzer

Journal of the American Chemical Society, Journal Year: 2024, Volume and Issue: 146(8), P. 5324 - 5332

Published: Feb. 14, 2024

The low coverage rate of anode OH adsorption under high current density conditions has become an important factor restricting the development industrial alkaline water electrolyzer (AWE). Here, we present our rare earth modification promotion strategy on using oxygen-friendly interface to increase NiS2 surface for efficient AWE catalysis. Density functional theory calculations predict that earths can enhance OH, and synthesis reaction mechanism is discussed in process spectrum. Experimentally, by preparing a series rare-earth-modified NiS2, relationship between coverage, active site density, catalytic activity was established attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy, time-resolved absorption spectra, so on. unique oxygenophilic properties thereby increasing sites Furthermore, Eu2O3/NiS2 assembled into equipment operated stably over 240 h at 300 mA cm–2 80 °C 30% KOH. Rare-earth-modified exhibits better than traditional non-noble metal catalysts Ni(OH)2 providing new approach solve problem anode.

Language: Английский

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Overall Water Splitting on The NiS/NiS₂ Heterostructures Featuring Self‐Equilibrium Orbital Occupancy

Advanced Energy Materials, Journal Year: 2023, Volume and Issue: 13(31)

Published: July 4, 2023

Abstract Efficient electrochemical overall water splitting requires bi‐functional catalysts that work for both hydrogen and oxygen evolution reactions (HER/OER). A heterostructure is thus proposed to maintain its optimal interactions with H/O‐containing intermediates. so‐called “orbital occupancy self‐equilibrium” strategy employed theoretically experimentally design such catalysts, namely the incorporation of V species into a NiS/NiS 2 heterostructure. Owing variable valences Ni species, electrons are controllably reoriented over interfacial V─S─Ni bond. The as‐generated dynamic self‐equilibrium electron environment modify an adsorption harmony toward various intermediates on this heterointerface, enhancing intrinsic activity reaction kinetics HER, OER, splitting. This V‐NiS/NiS catalyst exhibits overpotential only 94 220 mV at current density 10 cm –2 HER respectively. expected be workable other metal provide insights agile allocation catalysts.

Language: Английский

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Electronic Structure Engineering in NiFe Sulfide via A Third Metal Doping as Efficient Bifunctional OER/ORR Electrocatalyst for Rechargeable Zinc‐Air Battery

Advanced Functional Materials, Journal Year: 2024, Volume and Issue: 34(21)

Published: Jan. 29, 2024

Abstract Ti, V, Cr, Mn, Co, and Cu, have been investigated as a third dopant in NiFe sulfide for enhanced oxygen evolution reaction (OER)/oxygen reduction (ORR). The effects of on surface electronic structure, conductivity, thermodynamic barrier are addressed discussed. For the OER, X‐ray photoelectron spectroscopy analysis shows that electron transferring from Ni to dopants enhances catalytic performance sulfide. Cu doped exhibits best OER performance. ORR, density functional theory calculation indicates upshift d‐band center (ɛ d ), while Cr downshifts ɛ . Among dopants, V leads optimized structure modification, giving adsorption energy *O Ni, lowest rate determining step ΔG 1 , ORR activity. By considering E 10 ‐E 1/2 together with maximum current limited diffusion NiFeVS OER/ORR bifunctionality. cathodic catalyst has also evaluated zinc air battery, demonstrating specific capacity 698 mAh g −1 power 190 mW cm −2 superior cycle stability 2400 cycles (400 h).

Language: Английский

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Mo−Ni‐based Heterojunction with Fine‐customized d‐Band Centers for Hydrogen Production Coupled with Benzylamine Electrooxidation in Low Alkaline Medium

Angewandte Chemie International Edition, Journal Year: 2023, Volume and Issue: 62(39)

Published: June 14, 2023

Benzylamine electrooxidation reaction (BAOR) is a promising route to produce value-added, easy-separated benzonitrile, and effectively hoist H2 production. However, achieving excellent performance in low alkaline medium huge challenge. The intimately correlated with effective coupling of HER BAOR, which can be achieved by manipulating the d-electron structure catalyst regulate active species from water. Herein, we constructed biphasic Mo0.8 Ni0.2 N-Ni3 N heterojunction for enhanced bifunctional toward coupled BAOR customizing d-band centers. Experimental theoretical calculations indicate that charge transfer causes upshift centers, one side facilitates decrease water activation energy optimize H* adsorption on promoting activity, other favors more easily adsorb OH* forming NiOOH Ni3 optimizing benzylamine, thus catalyzing effectively. Accordingly, it shows an industrial current density 220 mA cm-2 at 1.59 V high Faradaic efficiencies (>99 %) production converting benzylamine benzonitrile 0.1 M KOH/0.5 Na2 SO4 . This work guides design electrocatalysts scalable green hydrogen value-added products.

Language: Английский

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Porous Organic Polymers‐Based Single‐Atom Catalysts for Sustainable Energy‐Related Electrocatalysis

Advanced Energy Materials, Journal Year: 2023, Volume and Issue: 13(28)

Published: June 8, 2023

Abstract Single‐atom catalysts (SACs) have been emerging as attractive catalytic materials in electrocatalysis for sustainable energy storage and conversion. To realize the practical implementation of SACs, reliable support is highly imperative to stabilize atomically dispersed metals with strong metal–support interaction, tunable local electronic environment, favorable electron/mass transport. Thanks great designability tunability composition, structure, morphology, porous organic polymers (POPs) demonstrated grand promise appropriate platforms toward design SACs at molecular level fabrication a controlled manner. Herein, comprehensive overview recent advances elucidation general principles, effective synthesis approaches, fundamental mechanisms boosting development high‐performance POPs‐based electrocatalytic transformations provided. The authors first outline rationales using supports principles electrocatalysis, followed by discussing approaches utilizing POPs POPs‐derived nanocarbons host single‐atom metals. Then, state‐of‐the‐art their applications heterogeneous (ORR, OER, HER, CO 2 RR, NRR) are discussed, which focus on revealing structure–performance correlation mechanisms. Finally, challenges strategies associated rational suggested.

Language: Английский

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Highly Reversible Zn–Air Batteries Enabled by Tuned Valence Electron and Steric Hindrance on Atomic Fe–N₄–C Sites

Nano Letters, Journal Year: 2024, Volume and Issue: 24(15), P. 4672 - 4681

Published: April 8, 2024

The bifunctional oxygen electrocatalyst is the Achilles' heel of achieving robust reversible Zn–air batteries (ZABs). Herein, durable electrocatalysis in alkaline media realized on atomic Fe–N4–C sites reinforced by NixCo3–xO4 (NixCo3–xO4@Fe1/NC). Compared with that pristine Fe1/NC, stability evolution reaction (OER) increased 10 times and reduction (ORR) performance also improved. steric hindrance alters valence electron at sites, resulting a shorter Fe–N bond enhanced sites. corresponding solid-state ZABs exhibit an ultralong lifespan (>460 h 5 mA cm–2) high rate (from 2 to 50 cm–2). Furthermore, structural NixCo3–xO4@Fe1/NC before after OER ORR as well charge–discharge cycling explored. This work develops efficient strategy for improving possibly other processes.

Language: Английский

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Iron‐Locked Hydr(oxy)oxide Catalysts via Ion‐Compensatory Reconstruction Boost Large‐Current‐Density Water Oxidation

Advanced Science, Journal Year: 2023, Volume and Issue: 10(16)

Published: April 7, 2023

Nickel-iron based hydr(oxy)oxides have been well recognized as one of the best oxygen-evolving catalysts in alkaline water electrolysis. A crucial problem, however, is that iron leakage during prolonged operation would lead to oxygen evolution reaction (OER) deactivation over time, especially under large current densities. Here, NiFe-based Prussian blue analogue (PBA) designed a structure-flexible precursor for navigating an electrochemical self-reconstruction (ECSR) with Fe cation compensation fabricate highly active hydr(oxy)oxide (NiFeO

Language: Английский

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