This study employs a one–step solvothermal approach to incorporate ferrocene (Fc) into nickel sulfide nanostructures, revealing exceptional electrocatalytic performance with an overpotential of 290 mV@10 mA cm⁻², surpassing traditional nickel sulfide catalysts. Fc−NiS demonstrates superior charge transfer characteristics, attributed to ferrocene‘s effect on electrical conductivity. With remarkable stability over 25 hours, Fc−NiS emerges as a promising non-noble-based catalyst for sustainable hydrogen production.

Abstract

Enhanced electrocatalysts that are cost-effective, durable, and derived from abundant resources are imperative for developing efficient and sustainable electrochemical water–splitting systems to produce hydrogen. Therefore, the design and development of non–noble–based catalysts with more environmentally sustainable alternatives in efficient alkaline electrolyzers are important. This work reports ferrocene (Fc)-incorporated nickel sulfide nanostructured electrocatalysts (Fc−NiS) using a one–step facile solvothermal method for water–splitting reactions. Fc−NiS exhibited exceptional electrocatalytic activity under highly alkaline conditions, evident from its peak current density of 345 mA cm⁻², surpassing the 153 mA cm⁻² achieved by the pristine nickel sulfide (NiS) catalysts. Introducing ferrocene enhances electrical conductivity and facilitates charge transfer during water–splitting reactions, owing to the inclusion of iron metal. Fc−NiS exhibits a very small overpotential of 290 mV at 10 mA cm⁻² and a Tafel slope of 50.46 mV dec⁻¹, indicating its superior charge transfer characteristics for the three–electron transfer process involved in water splitting. This outstanding electrocatalytic performance is due to the synergistic effects embedded within the nanoscale architecture of Fc−NiS. Furthermore, the Fc−NiS catalyst also shows a stable response for the water–splitting reactions. It maintains a steady current density with an 87% retention rate for 25 hours of continuous operation, indicating its robustness and potential for prolonged electrolysis processes.