Fabrication of CoFe-LDH nanosheets@CoP nanowires hierarchical heterostructure with enhanced bifunctional electrocatalytic activity for alkaline water splitting

Abstract

Exploring high active, low cost and stable electrocatalysts to replace noble precious metals has always been the major challenge in overall water splitting applications. Herein, CoFe-layered double hydroxide/Cobalt phosphide heterostructures on nickel foam (CoFe-LDH@CoP/NF) have been synthesized by using hydrothermal, chemical vapor deposition (CVD) and electrodeposition methods. The CoFe-LDH nanosheet is uniformly deposited on the surface of CoP nanowires to create the heterostructure. The formation of heterostructure increases active surface area, accelerates charge transfer velocity, optimizes the kinetics of reaction, thereby significantly improves electrocatalytic activity of the materials. The CoFe-LDH@CoP/NF attains 10 mA cm−2 with a low overpotential of 238 mV for OER and only 63 mV for HER. The catalyst provides the current density of 10 mA cm−2 throughout the overall water splitting by only requiring a low potential of 1.54 V. The CoFe-LDH@CoP/NF as an ideal electrocatalyst provides new ideas for developing efficient non-noble metal-based overall water splitting catalysts.