Triggering the water oxidation kinetics of NiMoO-NC for sustainable green hydrogen production

Abstract

Electrocatalytic water splitting depends significantly on the strategic design of efficient and durable catalysts that are cost-effective and composed of earth-abundant materials. To this end, a highly active electrocatalyst is essential for driving the OER process. This research work established a clear and accessible strategy for fabricating a metal oxide electrocatalyst functionalized with a conductive polymer, NiMoO-NC, synthesised by in situ oxidative polymerization aimed at advancing its application in water splitting. The generated NiMoO-NC/NF electrocatalyst exhibited overpotential and Tafel values of around 251 mV and 48 mV dec⁻¹ at 10 mA cm⁻². The stability of the electrocatalyst for OER activity was retained for up to 80 h. The kinetic study via operando EIS inferred less resistance with high conductivity to improve the OER kinetics of NiMoO-NC. Furthermore, the exceptional OER activity was confirmed by Bode analysis. The temperature-dependent analyses inferred that NiMoO-NC showed a lower activation energy of 5.1 kJ mol⁻¹ to promote the kinetics. The as-designed NiMoO-NC electrocatalyst shows great potential for advanced hydrogen technologies owing to its efficient electron transfer capability, excellent stability and high performance in the water oxidation process.