Cd-Doped CoFeP Nanosheet Arrays as Efficient Bifunctional Electrocatalysts for Overall Water Splitting

Developing a high-performance and long-stable noble-metal-free bifunctional electrocatalyst for both hydrogen evolution reaction (HER) and oxygen evolution reactions (OER) is of vital importance for industrial applications. Herein, we developed a Cd-doped CoFeP (Cd-CoFeP) free-standing electrocatalyst on nickel foam (NF), which is in favor of producing a large number of active sites and improves the intrinsic catalytic activity. In addition, the modulated electronic structure enables a faster charge-transfer process in Cd-CoFeP. Notably, the optimized Cd-CoFeP/NF electrocatalyst delivers low overpotentials of 71 and 244 mV for driving HER and OER at 10 mA·cm –2 in an KOH electrolyte. Moreover, the water splitting electrolytic cell by Cd-CoFeP/NF as the cathode and anode shows a voltage of only 1.55 V at 10 mA·cm –2 while maintaining good durability of 95% after 24 h. This research provides a feasible strategy for constructing the advanced electrocatalytic system by modulating the electronic structure to drive the overall water splitting.