Synergistic coupling of NiTe nanoarrays with RuO2 and NiFe-LDH layers for high-efficiency electrochemical-/photovoltage-driven overall water splitting

Abstract For hydrogen generation with water splitting, the sluggish reaction kinetics, the scarcity and costliness of the precious-metal catalysts make their practical applications being a big challenge. Herein, heterogeneous catalysts of NiTe@RuO2 and NiTe@NiFe-LDH are constructed by coupling ruthenium oxide (RuO2) and nickel-iron layered double hydroxide (NiFe-LDH) on T-shaped NiTe. The as-made NiTe@RuO2 and NiTe@NiFe-LDH catalysts exhibit outstanding hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) activity, respectively. Theoretical calculation and experimental measurement show that the electron transfer at the interface favors the H* adsorption during HER process. We construct full electrochemical cells for overall water splitting using NiTe@RuO2 as the cathode and NiTe@NiFe-LDH as the anode, which delivers a current density of 200 mA cm−2 under a voltage of 1.63 V. When powdered by a solar cell with a voltage of 1.5 V, the full-cell worked well for continuous hydrogen/oxygen generation, showing its potential for sustainable green energy generation.