Rich Se nanoparticles modified cobalt carbonate hydroxide as an efficient electrocatalyst for boosted hydrogen evolution in alkaline conditions

Abstract Nonprecious metal hydroxides are promising electrocatalyst candidates for oxygen evolution reaction. However, their hydrogen evolution reaction (HER) performance is not satisfactory, which limits their application for water splitting. Herein, a facile electrodeposition reduction strategy was applied to fabricate rich Se nanoparticles modified cobalt carbonate hydroxide nanoarrays on carbon cloth (Se NPs/CoCH NAs/CC) with η10 of 84.3 mV for HER, which is much smaller than that of original CoCH NAs/CC (η10 = 347.7 mV). The superior performance of Se NPs/CoCH NAs/CC was due to its large active surface area, rich active sites, and synergistic effect between Co-Se. DFT simulations also revealed that free energy for atomic hydrogen adsorption is much lower on Se NPs/CoCH (0.75 eV) than on CoCH (1.36 eV). Moreover, this work offered a simple and efficient strategy for developing hierarchical selenium/hydroxides with outstanding HER performance, which contributed to the cost and energy savings for mass hydrogen production.