Nanosecond laser texturing of Ni electrodes as a high-speed and cost-effective technique for efficient hydrogen evolution reaction

We texture the Ni electrodes by nanosecond lasers under different conditions and study their electrochemical performance for hydrogen evolution reaction through alkaline water electrolysis. The parameters we vary are the ambient gas (air, N2, and Ar) and laser wavelength (1064 or 355 nm), focal length of the f-0 lens (160 and 63 mm), laser power, and beam overlapping. Using a 1 M KOH electrolyte at room temperature we find that the Ni electrode textured by the 355 nm laser in N2 gas with the f-0 lens of focal length 160 mm shows the best electrochemical performance. The attained overpotential at the current density of -200 mA/cm2 and Tafel slope are 275 mV and 78 mV/dec, respectively. Our results demonstrate that nanosecond laser texturing is a highspeed and cost-effective technique which is industrially suitable to fabricate efficient electrodes for hydrogen evolution reaction.