According to the density functional theory calculations, the crystal surface with the best catalytic properties is Ni (111). Based on the theoretical calculations, this work proposed controlling the reduction order and reduction efficiency of Ni2+ and H2O in the nickel slag leachate during electrolysis to modulation of crystal surface growth of Ni. Moreover, amorphous Ni(OH)2 was designed to selectively grow in Ni product to further improve the catalytic performance of Ni (1 1 1).
The electrodes with the best catalytic performance for hydrogen evolution were obtained when the electrodeposition conditions were 30 min, 0.05 M, and 12.5 mA/cm2. A current density of 10 mA/cm2 was achieved with an overpotential of only 17.46 mV. The Tafel slope was 31.2 mV·decâ1. The proposed method is a straightforward and clean approach that does not require membrane addition. At the same time, using nickel slag as raw material can not only reduce the harm of nickel slag to the environment, but also reduce the cost of preparing electrodes.