Modulating electronic structure of cobalt phosphide porous nanofiber by ruthenium and nickel dual doping for highly-efficiency overall water splitting at high current density

Abstract

Abstract The rational design and construction of high-efficiency bifunctional electrocatalysts are the central challenges for improving the overall water splitting efficiency. In this paper, Ru and Ni dual-metal doped CoP (Ru, Ni–CoP) porous nanofibers were fabricated. Dual-metal doping can be more efficiently used to modulate the electronic structure than single-metal doping, thereby, achieving decreased water dissociation energy and optimized adsorption energy for different reaction intermediates. Consequently, Ru, Ni–CoP porous nanofibers exhibit highly enhanced bifunctional activities. The electrolytic cell based on Ru, Ni–CoP porous nanofibers, which is significantly superior to Pt/C‖IrO2 pairs, requires a low voltage of 1.448 and 1.757 V at 10 and 500 mA cm−2, respectively. The electrolytic cell exhibits excellent long-term stability at 400 mA cm−2. This excellent activity and stability at high-current density provides the considerable potential for the practical applications of Ru, Ni-CoP porous nanofibers as high-performance bifunctional electrocatalysts.