Aqueous substitution synthesis of platinum modified amorphous nickel hydroxide on nickel foam composite electrode for efficient and stable hydrogen evolution

Exploring highly active and stable electrocatalysts toward hydrogen evolution reaction (HER) is vital for the production of green energy and storage of intermittently renewable electrical energy. In this study, we fabricate Pt-modified Ni(OH)(2) on 3D nickel foam (Pt content: 1.5 wt %) via a one-step galvanic replacement reaction in aqueous solution to achieve a top performance of HER under alkaline conditions. It exhibits a negligible onset potential, a Tafel slope of 17 mV dec(-1), and overpotentials of 38, 114, and 203 mV to deliver 10, 50, and 100 mA cm(-2) current densities, respectively, which outperforms the commercial Pt/C and Pt sheet. Moreover, this catalyst shows enhanced durability towards HER, sustaining electrolysis at -20 mA cm(-2) for 4, 500 min in 1 M KOH with little degradation. Its good performances come from the synergism of flake-like Pt and amorphous Ni(OH)(2). This work provides not only a facile and easy scale-up approach to fabricate Pt-modified electrocatalysts with improved HER performance but also a new strategy to design self-supported high-performance hybrid materials of noble-metal and amorphous transitional metal hydroxides for sustainable energy conversion and storage. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.