Unveiling the promotion of accelerated water dissociation kinetics on the hydrogen evolution catalysis of NiMoO4 nanorods

Nickel molybdate (NiMoO4) attracts superior hydrogen desorption behavior but noticeably poor for efficiently driving the hydrogen evolution reaction (HER) in alkaline media due to the sluggish water dissociation step. Herein, we successfully accelerate the water dissociation kinetics of NiMoO4 for prominent HER catalytic properties via simultaneous in situ interfacial engineering with molybdenum dioxide (MoO2) and doping with phosphorus (P). The as-synthesized P-doped NiMoO4/MoO2 heterostructure nanorods exhibit outstanding HER performance with an extraordinary low overpotential of -23 mV at a current density of 10 mA cm(-2), which is highly comparable to the performance of the state-of-art Pt/C coated on nickel foam (NF) catalyst. The density functional theory (DFT) analysis reveals the enhanced performance is attributed to the formation of MoO2 during the in situ epitaxial growth that substantially reduces the energy barrier of the Volmer pathway, and the introduction of P that provides efficient hydrogen desorption of NiMoO4. This present work creates valuable insight into the utilization of interfacial and doping systems for hydrogen evolution catalysis and beyond.(C) 2021 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by ELSEVIER B.V. and Science Press. All rights reserved.

Automated summary

The water dissociation kinetics of nickel molybdate were successfully accelerated through in situ interfacial engineering and phosphorus doping, resulting in outstanding hydrogen evolution catalytic properties.