β-Ni(OH)2 mediated redox catalysis for efficient hydrogen generation by reducing accumulation of bubbles in water splitting

Abstract

The water-splitting efficiency depends on the design of electrodes, choice of electrode materials, and electrocatalysts for industrial and commercial use. Here, we report the design of screw pitch cylindrical electrodes deposited with β-Ni(OH)2 hexagonal nanostructures synthesized by microwave-assisted wet chemical method to overcome the accumulation of bubbles on the electrode surface. Further, β-Ni(OH)2/NiOOH coupled redox catalysis enhances electrocatalytic activities leading to a very low overpotential of 71 mV and 98 mV needed to obtain a current density of 10 mA/cm2 with a low Tafel slope of 41.2 and 32.27 mV/dec for hydrogen and oxygen evolution respectively. The remarkable hydrogen conversion efficiency of 40.39% is obtained over 250 h of electrochemical water splitting with less than 5% fluctuation. The result assures a promising method for the mass production of hydrogen fuel with high current density and long durability performance using naturally abundant materials.