Direct fabrication of nanoscale NiVOx electrocatalyst over nickel foam for high-performance oxygen evolution reaction

Pursuit of competent water oxidation catalysts operating at low onset overpotential (<1.50 V vs. RHE), achieving high current densities (>1000 mA/cm²) over narrow potential range, and showing tremendous durability is an escalating hot issue and remains a grand challenge. In this study, high-activity water oxidation is shown over noble-metal-free, bimetallic nickel vanadium oxide (NiVO_x) thin-film electrocatalyst developed over three-dimensional nickel foam (NF) via single-step aerosol assisted chemical vapor (AACVD) technique under controlled conditions. Distinct morphological transformations from micro-nano to the nanoscale catalytic structure are observed by simply increasing deposition time from 60 to 180 minutes. The catalyst prepared for 180 minutes (NiVO_x/NF₁₈₀) initiates OER at the mere potential of 1.42 V vs. RHE, exhibits current decade at 1.44 V vs. RHE, peak current density > 1200 mA/cm² at just 1.64 V vs. RHE, low Tafel slope of 60 mV/dec, and remarkable stability during prolonged period water oxidation catalysis. The catalytic activity is comparable and even better than state-of-art Ru-based catalysts investigated in alkaline conditions. The high activity can be ascribed to subtly modulated local coordination environment and electronic structure of the Ni/V compound in the nano-textured catalyst. This work provides a competent, efficient, and high-efficiency anodic oxygen evolution and chemical energy conversion catalyst that is easily accessible via a straightforward AACVD route while employing simple precursors.