Comparison of three nickel-based carbon composite catalysts for hydrogen evolution reaction in alkaline solution

In this work, preparing three nickel-based carbon composite catalysts (Ni-OCNT, Ni-ONC and Ni-rGO) by supergravity field electrodeposition for hydrogen evolution reaction (HER) from nickel sulfamate bath containing suspended nano-sized carbon materials. The crystal structure, morphology and chemical compositions of the composite catalysts were characterized by XRD and SEM measurements. The electrochemical activity of composite coatings for HER was determined by polarization measurement and electrochemical impedance spectroscopy in 1.0 M NaOH solution. The prepared nickel-based carbon composite catalysts exhibit a significant enhancement in electrocatalytic activity for HER compared with pure Ni electrode. In addition, the Ni-rGO, Ni-ONC, Ni-OCNT catalysts prepared under supergravity field demand overpotentials of 245, 177, 91 mV and 286, 224, 154 mV and 330, 286, 222 mV to drive current densities of 80, 30, 10 mA cm(-2), respectively. Ni-rGO cathode presents excellent HER activity with lowest overpotentials. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.