Nanoporous CoP3 Nanowire Array: Acid Etching Preparation and Application as a Highly Active Electrocatalyst for the Hydrogen Evolution Reaction in Alkaline Solution

Transition-metal phosphides have been intensively and extensively studied as earth-abundant catalysts for effective hydrogen evolution electrocatalysis, but it is highly desired to explore a new strategy to improve the catalytic activity. In this work, a nanoporous CoP3 nanowire array on Ti mesh (np-CoP3/TM) was derived from MnO2-CoP3/TM by acid etching of MnO2 that acts as a pore forming agent. As a non-noble-metal catalyst for the hydrogen evolution reaction, the resulting np-CoP3/TM demonstrates enhanced performance with the need of an overpotential of 76 mV (j = 10 mV cm(-2)), 45 mV less than that needed by MnO2-CoP3/TM. Moreover, it also shows a good durability for at least 60 h.