Effective electrocatalytic overall water splitting over a pearl chain-like NiCoP/CNT hybrid sponge electrode in basic solution

Abstract

The electrocatalytic splitting of water into H₂ and O₂ is a potential method for continuous and controllable production of clean energy. Herein, we developed a pearl chain-like nickel cobalt phosphide (NiCoP) nanoparticle-modified 3D CNT sponge electrode by a simple electrodeposition method. The NiCoP/CNT hybrid electrode was found to exhibit excellent electrocatalytic performance for HER and OER in the alkaline solution (1 M KOH). In particular, the NiCoP/CNT hybrid electrodes generated 10 and 100 mA cm⁻² cathodic currents at overpotentials of 73 mV, and 140 mV, respectively. Meanwhile, the NiCoP/CNT compounds generated anodic currents of 10 and 100 mA cm⁻² at overpotentials of 288 and 353 mV, respectively. More specifically, no significant degradation was observed after a 100 h stability test with connecting the NiCoP/CNTs (+) and NiCoP/CNTs (−) in two-electrode system for water splitting under KOH solution. This work demonstrated that bifunctional transition metal electrocatalyst would be a wonderful catalyst for overall water splitting in basic aqueous solution.