Ni(OH)2 -WP Hybrid Nanorod Arrays for Highly Efficient and Durable Hydrogen Evolution Reactions in Alkaline Media.

The development of efficient non-noble-metal hydrogen evolution electrocatalysts in alkaline media is crucial for sustainable, ecofriendly production of H2 through water electrolysis. An alkaline hydrogen evolution reaction (HER) catalyst composed of Ni(OH)2 -decorated thungsten phosphide (WP) nanorod arrays on carbon paper was synthesized by thermal evaporation and electrodeposition. This hybrid catalyst displayed outstanding HER activity and required a low overpotential of only 77 mV to obtain a current density of 10 mA cm-2 and a Tafel slope of 71 mV dec-1 . The hybrid catalyst also showed long-term electrochemical stability, maintaining its activity for 18 h. This improved HER efficiency was attributed to the synergetic effect of WP and Ni(OH)2 : Ni(OH)2 effectively lowers the energy barrier during water dissociation and also provides active sites for hydroxyl adsorption, whereas WP adsorbs hydrogen intermediates and efficiently produces H2 gas. This interfacial cooperation offers not only excellent HER catalytic activity but also new strategies for the fabrication of effective non-noble-metal-based electrocatalysts in alkaline media.