Mesoporous CoP Nanowire Arrays for Hydrogen Evolution

Abstract

Morphology and structure engineering are feasible routes to tuning the hydrogen evolution reaction (HER) catalytic activity of cobalt phosphides. In this work, we developed self-supported Zn-incorporated mesoporous cobalt phosphide nanowire arrays (Zn-Co-P) on Ni foam as an efficient HER electrocatalyst. Electrochemical tests show that the HER catalytic activity of Zn-Co-P has been improved by Zn incorporation and the measured overpotentials are 167 and 172 mV at a geometric catalytic current density of 100 mA·cm–2 in 0.5 M H2SO4 and 1.0 M KOH, respectively. Further characterizations reveal that the mesopores exposed on the surface induced by Zn incorporation play a key role in the enhanced HER performance of Zn-Co-P by providing more active sites. Moreover, Zn incorporation can promote the formation of a CoP phase, which is also beneficial to the overall catalytic activity.