Bifunctional NiCo‐CuO Nanostructures: A Promising Catalyst for Energy Conversion and Storage

Small Methods, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 15, 2025

Abstract This investigation explores the potential of co‐incorporating nickel (Ni) and cobalt (Co) into copper oxide (CuO) nanostructures for bifunctional electrochemical charge storage oxygen evolution reactions (OER). A facile wet chemical synthesis method is employed to co‐incorporate Ni Co CuO, yielding diverse nanostructured morphologies, including rods, spheres, flake. The X‐ray diffraction (XRD) Raman analyses confirmed formation NiCo‐CuO nanostructure, with minor phases (NiO) tetraoxide (Co 3 O 4 ). High‐resolution Transmission Electron Microscope (HRTEM) also confirms morphologies oxides. Synchrotron absorption spectroscopy revealed higher states Cu, Ni, in enhancing its OER. Site‐selective near edge structure analysis elucidated spatial distribution nanostructure. Furthermore, extended fine provided insights local atomic structures, revealing increased coordination numbers interatomic distances In situ discloses transformation hydroxide (Co(OH) 2 ) (CoO) oxyhydroxide (CoOOH) exhibited superior specific capacitance, favorable Tafel behavior, low overpotential positioning as promising materials energy conversion applications. work contributes development efficient CuO nanocatalysts.

Language: Английский

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Dense Crystalline‐Amorphous Nano‐Interfaces Derived from Local Reconstruction for Alkaline Hydrogen Evolution

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

Published: Dec. 13, 2024

Abstract The crystalline‐amorphous ( c‐a ) interface can provide abundant accessible active sites and high intrinsic activity for hydrogen evolution reaction (HER); however, conventional methods only produce sparse between hetero‐phases. Here, a novel soluble dopant‐induced local self‐reconstruction strategy to yield dense nano‐interfaces is presented, as demonstrated by Mo doped‐NiP pre‐catalyst. During the cathodic polarization in alkaline electrolyte, dopant initially dissolves, generating nano‐voids within NiP nanosheets; subsequently forms situ ultrafine amorphous MoO 3 nanoparticles, ranging from 2 4 nm size, embedded crystalline nanosheets. Compared with surface reconstruction that generates interface, proposed “dopant‐dissolution‐redeposition”, occurred inner regions around dopants, nano‐interface. Theoretical calculations reveal efficiently modulate electronic structure of interfacial lower HER overpotential. Benefiting nano‐interface, amorphous/crystalline /Mo‐NiP exhibits outstanding performance, achieving current density 10 mA cm −2 at ultra‐low overpotentials 26 mV long‐term stability 1 M KOH. This work provides basis tuning composition‐structure‐property relationships materials both interior.

Language: Английский

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Ultrafast synthesis of biphase Ni-doped FeOOH for efficient and stable oxygen evolution at high current density

Applied Physics Letters, Journal Year: 2024, Volume and Issue: 125(15)

Published: Oct. 7, 2024

NiFe oxyhydroxides, generally reconstructed on surface during oxygen evolution reaction (OER), are real active species for water oxidation; however, their direct and convenient preparation remains challenging. Here, we develop a one-step approach to prepare biphase (α/δ) Ni-doped FeOOH catalyst in 3 min under room temperature. The core of this ultrafast method is that Fe2+ derived from the redox Fe3+ Ni2+ accelerate Fenton-like reaction, while simultaneously producing mixed-valence Ni ions(Ni2+, Ni3+) results not only homovalent heterovalent doping, but also heterojunction with high low crystallinity. Specifically, doping leads preferred formation low-crystalline δ-oriented abundant vacancies, which favor triggering lattice mechanism (LOM) OER. Benefitting high/low crystalline LOM, optimized Ni-FeOOH merely needs overpotential 300 mV reach 1000 mA cm−2 OER alkaline electrolyte shows excellent durability even at current density 500 cm−2. This work provides cost-effective strategy fabricate highly robust non-noble electrocatalysts can potentially be applied industrial-scale electrolysis.

Language: Английский

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Cooperative coupling of microscopic enhanced electric field and macroscopic efficient bubble traffic for industrial hydrogen evolution

Applied Physics Letters, Journal Year: 2024, Volume and Issue: 125(7)

Published: Aug. 12, 2024

The alkaline hydrogen evolution reaction (HER) for industrial generation is a promising way to achieve intermittent energy storage. However, challenges, such as the insufficient supply of adsorbed atoms (*H) and slow bubble dynamics, hinder development HER. Here, we report cooperative strategy by leveraging both microscopic enhanced electric field macroscopic efficient traffic evolution, demonstrated through NiCoP nanotips on NiP nanorods (NiCoP-tip@NiP). Specifically, during HER process, can accumulate large number electrons, enhancing Stern layer. This accelerates dissociation water, resulting in favorable *H Simultaneously, confined space between hinders growth bubbles generated at tips. Newly formed will push out existing bubbles, thus accelerating gas release. As result, NiCoP-tip@NiP exhibits low overpotential 300 mV 1000 mA cm−2 maintains stable operation over 90 h approximately processes. provides profound insights generation.

Language: Английский

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