Core–Shell Cu@CoP as Highly Efficient and Durable Bifunctional Electrodes for Electrochemical Water Splitting
Peican Wang, Yuqun Lin, Lei Wan, Baoguo Wang
Abstract
Developing efficient, cheap, and clean electrocatalysts for the hydrogen/oxygen evolution reaction (HER/OER) has important significance for reducing energy consumption for electrochemical water splitting. Herein, the core–shell Cu@CoP on the copper mesh was successfully synthesized. The hierarchically structured Cu@CoP exhibits high surface areas and rapid electron transfer ability, leading to enhanced catalytic activity. As-prepared Cu@CoP/Cu electrodes need an overpotential of 98 mV to obtain 10 mA cm–2 for HER in acidic solutions. This integrated catalyst also demands overpotentials of 88 and 270 mV to reach 10 mA cm–2 for HER and OER in alkaline solution, respectively. The Cu@CoP/Cu is employed as bifunctional electrodes for water electrolysis. For acid/alkaline systems, the performance of the Cu@CoP/Cu-derived cell is comparable to noble-metal-based water electrolysis. For the alkaline water-splitting system, the performance of the Cu@CoP/Cu-derived cell is superior to noble-metal-based water electrolysis, which needs an electrolysis voltage of 1.65 V to obtain 10 mA cm–2.