Self-encapsulated Copper-Doped Nickel Porous Nanoclusters for Urea-Assisted Electrolytic Hydrogen Production

doi:10.15541/jim20260140

Abstract

Abstract: Urea-assisted electrolytic hydrogen production saves energy and reduces emissions, where developing high-activity electrode materials is critical. A self-encapsulated Cu-doped Ni catalyst (Ni(Cu)/NF) with a NiO phase was constructed on Ni foam (NF) via pulse voltammetric deposition and constant-potential dissolution. The material features a three-tier porous architecture (100 nm floral nanopores, 300-500 nm nanoclusters, and NF micropores), delivering an electrochemical active area (ECSA) 12.17 times that of bare NF and providing abundant active interfaces and mass-transfer channels for the hydrogen evolution reaction (HER) and urea oxidation reaction (UOR). Cu doping induces lattice distortion in the Ni-rich phase, which, together with strong electronic interactions from the surface NiO/Ni heterojunction, synergistically boosts intrinsic catalytic activity. In 1 mol·L^-1 KOH, Ni(Cu)/NF achieves 10 mA^-2 with an HER overpotential of only 53 mV and a UOR potential of only 1.364 V. The assembled urea-assisted electrolyzer requires only 1.732 V to deliver 500 mA·cm^-2, outperforming commercial noble-metal catalysts, and shows excellent stability with a voltage rise rate of only 0.38 mV·h^-1 after 120 h. This “structure-electronics” synergistic strategy offers a new route to efficient and stable bifunctional catalysts for urea-assisted hydrogen production.

Key words: copper doping, nickel-copper alloy, heterojunction, urea oxidation reaction, hydrogen evolution reaction, synergistic effect

CLC Number:

TQ151
O611

SUN Qiangqiang, WANG Dan, JIANG Meina, ZHOU Ziwen, REN Xiaona, ZHANG Mengyi, LI Chun. Self-encapsulated Copper-Doped Nickel Porous Nanoclusters for Urea-Assisted Electrolytic Hydrogen Production[J]. Journal of Inorganic Materials, DOI: 10.15541/jim20260140.

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