Integrating strain engineering into the design and fabrication of large-area electrodes with highly efficient alkaline hydrogen evolution reaction (HER) performance is still a big challenge. Herein, a 6-meter-long CuNi/NiPt 1 % alloy cathode with excellent performance has been synthesized through epitaxial growth on the surface of microcone array using our self-developed roll-to-roll electrodeposition system. It delivers ultralow overpotentials of 58.2 ± 4.5 and 158.2 ± 11.2 mV at 100 and 1000 mA cm −2 , respectively, with a low Tafel slope of 28.5 mV dec −1 and an ultra-high mass activity of 64.7 mA μg Pt −1 @ 100 mV. It maintains 99 % activity retention after 2000-h operation at 1 A cm −2 and withstands harsh industrial conditions including high-frequency fluctuating load (20–120 %, 1/20 Hz, 100 h) and ultrasonic cavitation (40 kHz, 300 W, 1 h). Multi-scale characterizations reveal that a 2.5 % tensile strain is induced by 50 nm-thick NiPt 1 % alloy layers epitaxially grown on the CuNi alloy cone array. This tensile strain enhances the Volmer-Tafel kinetics by reducing activation energy by 26 % and increases surface *H coverage by 4.2-fold. DFT calculations further confirm it enables the transformation of non-spontaneous water dissociation into a spontaneous process, reducing the reaction’s energy barrier by 30 %. Additionally, *H adsorption across all surface sites of NiPt 1 % alloy is greatly enhanced, resulting in a reduction of 20 % in energy barrier for Tafel reaction. This work proposes a simple and scalable strategy for integrating strain engineering into alloy cathodes with excellent alkaline HER performance.
Developing highly efficient catalysts with ultralow-loading metal is still hindered by the sluggish Volmer–Tafel kinetics for the alkaline hydrogen evolution reaction (HER). Herein, an efficient catalyst was designed and constructed on nickel foam by integrating oxyphilic Y-doped NiO with NiPt1% nanocrystalline via a facile one-step electrodeposition. It requires only 21.2 and 178.5 mV to achieve 10 and 1000 mA cm–2, with a low Tafel slope of 27.8 mV dec–1. Furthermore, it provides an ultrahigh mass activity of 42.7 mA μgpt–1 @ 100 mV and a high stability over 2000 h at 1 A cm–2 almost without potential decay. In-situ experiments and D2O electrolysis tests reveal that the oxyphilic Y-NiO component not only reduces the activation energy of NiPt1% alloy by 32% and enhances its surface hydrogen (*H) coverage 7.8 times but also markedly boosts the Volmer step. Density functional theory calculations further reveal that Y-NiO strengthens water adsorption and shifts both Volmer and Tafel steps on the NiPt1% alloy surface from nonspontaneous to spontaneous, while reducing their energy barriers by 32 and 23%, respectively. This work presents an effective approach for regulating the Volmer–Tafel process in ultralow-loading metal alloys for alkaline HER.
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