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Exploiting low-cost and high-activity catalysts is crucial for lowering energy consumption for hydrogen evolution reaction (HER). Herein, we reported a pure Nickel catalyst with high activity and long-term stability at a large current density in an alkaline medium. We employed an industrial machining technology, turning processing, to generate Ni-chips, a self-supported catalyst, with mostly close-packed planes exposed and high compressive strain. The close-packed plane and compressive strain jointly lower the d -band center of the nickel catalyst and overcome the excessive adsorption for reactive intermediates. As such, Ni-chip achieves ultralow overpotentials of 70 mV at 10 mA cm−2 and 297 mV at 1000 mA cm−2. Particularly, the catalyst exhibits outstanding stability at high current density (1 A cm−2), after working for one and a half months (ca. 1070 h), the initial current density merely declined by 7.3%. With its remarkable catalytic activity, excellent stability, ease of synthesis, and utilization of metallic scraps, the Ni-chip catalyst may serve as a promising catalyst for industrial applications. Ni-chip catalysts with high compressive strain and predominantly close-packed planes were prepared through turning processing. This combination effectively mitigated the excessive adsorption of *OH and *H on the Ni surface, enabling an ultralow overpotential of 297 mV at 1000 mA cm-2, and excellent stability at 1 A cm-2 for 1070 h, demonstrating potential as an efficient and durable electrocatalyst. [Display omitted] [ABSTRACT FROM AUTHOR]

As a cheap and earth-abundant metal, copper is known highly conductive but inactive for catalyzing hydrogen evolution reaction (HER) due to its fully filled d orbital and weak adsorption for hydrogen intermediate. Herein, we adopt a mechanical stirring process to introduce a large number of dislocations into copper plate, and retain the dislocations by the quenching effect of dry ice. Theoretical computation indicates that dislocation can cause uneven distribution of charge density, and the electron-deficient area remarkably enhances the hydrogen adsorption, turning inactive copper into active HER catalyst. The product achieves high turnover frequency, low overpotential and long-term durability. Our work bridges mechanical process and functional materials, and exploits a powerful technology on producing self-supported catalysts in a rapid way : [Display omitted] [ABSTRACT FROM AUTHOR]