Pt modified NiMoO4-GO/NF nanorods with strong metal-support interaction as efficient bifunctional catalysts for overall water splitting

Abstract

Catalysts for the electrolysis of water are critical in the production of hydrogen for the energy industry. The use of strong metal-support interactions (SMSI) to modulate the dispersion, electron distribution, and geometry of active metals is an effective strategy for improving catalytic performance. However, in currently used catalysts, the supporting effect does not significantly contribute directly to catalytic activity. Consequently, the continued investigation of SMSI, using active metals to stimulate the supporting effect for catalytic activity, remains very challenging. Herein, the atomic layer deposition technique was employed to prepare an efficient catalyst composed of platinum nanoparticles (Pt NPs) deposited on nickel-molybdate (NiMoO4) nanorods. Nickel-molybdate’s oxygen vacancies (Vo) not only help anchor highly-dispersed Pt NPs with low loading but also strengthen the SMSI. The valuable electronic structure modulation between Pt NPs and Vo resulted in a low overpotential of the hydrogen and oxygen evolution reactions, returning results of 190 mV and 296 mV, respectively, at a current density of 100 mA cm−2 in 1 M KOH. Ultimately, an ultralow potential (1.515 V) for the overall decomposition of water was achieved at 10 mA cm−2, outperforming state-of-art catalysts based on the Pt/C || IrO2 couple (1.668 V). This work aims to provide reference and a concept for the design of bifunctional catalysts that apply the SMSI effect to achieve a simultaneous catalytic effect from the metal and its support.