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Research Article

V-doped Ni3N/Ni heterostructure with engineered interfaces as a bifunctional hydrogen electrocatalyst in alkaline solution: Simultaneously improving water dissociation and hydrogen adsorption

Huan ZhangJuan WangFengqi QinHuiling Liu( )Cheng Wang( )
Tianjin Key Laboratory of Advanced Functional Porous Materials,Institute for New Energy Materials and Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology,Tianjin,300384,China;
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Abstract

Alkali-water electrolyzers and hydroxide exchange membrane fuel cells are emerging as promising technologies to realize hydrogen economy. Developing cost-effective electrode materials with high activities towards corresponding hydrogen evolution (HER) and oxidation (HOR) reactions plays a crucial role in commercial hydrogen production and utilization. Herein, we fabricated a V-doped Ni3N/Ni heterostructure (V-Ni3N/Ni) through a controlled nitridation treatment on a V-incorporated nickel hydroxide precursor. The resultant catalyst exhibits comparable catalytic activity and durability to commercial Pt/C in terms of both HER (a low overpotential of 44 mV at the current density of 10 mA·cm-2) and HOR (a high current density of 1.54 mA·cm-2 at 0.1 V versus reversible hydrogen electrode) under alkaline conditions. The superior activity of V-Ni3N/Ni grown on different substrates further implies its intrinsic performance. Density functional theory (DFT) calculations reveal that the coupled metallic Ni and doped V can promote the water adsorption, accelerate the Volmer step of alkaline HER, as well as optimize the adsorption and desorption of hydrogen intermediate (H*) to reach a balanced ΔGH* value.

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Nano Research
Pages 3489-3496
Cite this article:
Zhang H, Wang J, Qin F, et al. V-doped Ni3N/Ni heterostructure with engineered interfaces as a bifunctional hydrogen electrocatalyst in alkaline solution: Simultaneously improving water dissociation and hydrogen adsorption. Nano Research, 2021, 14(10): 3489-3496. https://doi.org/10.1007/s12274-021-3559-9
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Received: 16 February 2021
Revised: 10 April 2021
Accepted: 01 May 2021
Published: 29 May 2021
© Tsinghua University Press and Springer-Verlag GmbH Germany, part of Springer Nature 2021
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