Abstract: Nanoporous Ni was prepared by rapid solidification and de-alloying. SEM and XRD were used for phase analysis and morphology characterization in our study. The electrocatalytic hydrogen evolution performance of nanoporous Ni electrode was meanwhile tested by means of linear sweep voltammetry (LSV), cyclic voltammetry (CV), and alternating current impedance (EIS). The results show that the Ni₅Al₉₅ precursor alloy can be de-alloyed at 65 ℃ for 4 h, obtaining multi-layered, bi-continuous nanoporous Ni. At a current density of 50 mA·cm^－2, the hydrogen evolution over-potential at 25 ℃ is 257 mV, the electric double layer capacitance is 4.7 mF·cm^－2, and the apparent activation energy during the hydrogen evolution reaction is 26.06 kJ·mol^－1. Electrochemical desorption becomes the control step for the whole reaction process. After 1 000 cycles of cyclic voltammetric endurance test, the polarization behaviors of nanoporous Ni electrode at 25 ℃ remains its original state. The hydrogen evolution over-potential decreased by 6 mV in the case of current density of 50 mA·cm^－2, which demonstrates excellent hydrogen evolution stability.

Key words: rapid solidification, de-alloying, nanoporous Ni, hydrogen evolution performance