A zinc-doped nickel–boron reconstructed catalytic electrode for efficient hydrogen evolution in a multi-pH system

Abstract

It is of great significance to construct efficient, economical and stable non-precious metal catalysts for direct water electrolysis for hydrogen production in various pH environments to alleviate the energy crisis and environmental pollution. Herein, a zinc-doped nickel–boron material self-supported catalytic electrode is constructed in situ on the surface of hydrophilic filter paper via mild electroless plating (NiB–Zn@HP). The Zn doping strategy is utilized to modify the electronic structure of Ni, optimize the synergistic effect of the bimetallic combination, and promote the adsorption equilibrium of H*/OH* intermediates to enhance the catalytic kinetics and stability of the hydrogen evolution reaction. The designed catalytic electrode can achieve a current density of 10 mA cm⁻² in alkaline simulated seawater (1.0 M KOH + 0.5 M NaCl) and neutral (1.0 M PBS) electrolyte with overpotentials of only 28 mV and 60 mV. More importantly, the flexible electrodes demonstrate the ability to be bent, folded, and molded to fit a variety of application scenarios, as well performing stable electrolysis in alkaline simulated seawater for more than 300 hours at a simulated industrial-scale current density (500 mA cm⁻²). This work provides strong theoretical support for the construction of efficient and economical catalytic electrodes for water electrolysis on an industrial scale, and future research will be able to better focus on their large-scale preparation processes, long-term performance in complex real-world environments, and mechanical evaluation.