Self-supported Pt nanoparticles-NiFeP nanosheets arrays nanohybrid with hydrophilic surface towards urea electrolysis

Abstract

Urea-assisted water electrolysis is a clean, sustainable, and energy-saving method towards hydrogen production. However, the development of earth-abundant, stable, and highly active bifunctional catalysts towards urea electrolysis is still a significant technical challenge. Herein, the highly dispersed Pt nanoparticles decorated NiFeP nanosheets arrays on nickel foam (Pt-NiFeP/NF) electrode is rationally designed, which combines the advantages of superhydrophilic interface, ultrathin nanostructure and open three-dimensional (3D) architecture. Consequently, Pt-NiFeP/NF displays a remarkable electroactivity towards both hydrogen evolution reaction (HER) and urea electrooxidation reaction (UEOR), which only needs the overpotential of 32 mV to achieve the current density of 10 mA cm−2 towards HER, and drives a current density of 50 mA cm−2 at 1.38 V towards UEOR. More importantly, the urea electrolysis system assembled with Pt-NiFeP/NF only requires a cell voltage of 1.41 V to achieve a current density of 100 mA cm−2, much lower than the traditional water electrolysis (1.94 V). This work promotes the application of Pt nanoparticles decorated bimetallic phosphides as a bifunctional catalyst towards urea-rich wastewater treatment and green electrochemical hydrogen production.