Nanostructured NiMoO4 Electrode Materials for Efficient Oxygen Evolution Reaction

Electrocatalysts derived from earth-abundant transition metals offer a viable alternative to noble metals for water electrolysis, yet they often suffer from poor catalytic behaviour and limited lifespan. In this study, nanostructured nickel molybdate on nickel foam (NiMoO4/NF) were synthesized via a straightforward hydrothermal process at three different durations (6, 12, and 24 h) to assess their oxygen evolution reaction (OER) performance. The electrodes, specifically NiMoO4-6h, NiMoO4-12h, and NiMoO4-24h, demonstrated significant OER activity in 1.0 M KOH solution, achieving overpotentials of 315 mV, 290 mV and 320 mV for respectively. Notably, the NiMoO4-12h electrode showed an exceptional stability, with only a 1.28% activity decrease after 200 hours at a current density of 10 mA cm-2. This study presents a novel approach to enhancing the electrocatalytic efficiency of these catalysts through optimizing their electrical conductivity, active surface sites, and surface reaction dynamics.