Tin doped nickel iron oxide nanomaterials as an efficient bifunctional electrocatalyst for overall watersplitting

Transition metal oxides, particularly those based on nickel and iron, are promising catalysts for water splitting reactions. However, designing efficient bifunctional electrodes for overall water splitting remains a significant challenge. This study focuses on the synthesis of tin-doped nickel iron oxide via a simple spray pyrolysis technique to explore its efficacy as a bifunctional electrocatalyst. The synthesized metal oxide demonstrated remarkable catalytic performance, with overpotential of 230 mV for the oxygen evolution (OER) and 277 mV for the hydrogen evolution reaction (HER). Furthermore, the material exhibited excellent stability, maintain continuous and uninterrupted operation for over seven days at an applied potential of 1.7 V, delivering a current density of 10 mA/cm 2 . The ease of synthesis, combined with the material’s high catalytic activity and durability, highlights its potential as a cost-effective and efficient candidate for water splitting applications. By simplifying the preparation process, this approach offers a practical pathway toward developing scalable and sustainable solutions for renewable hydrogen production. • The present work emphasizes on designing binder free bifunctional electrodes for overall water splitting. • Tin doped nickel iron oxide has been prepared via spray pyrolysis and used as bifunctional electrode. • The overpotential for OER and HER process is 230 mV and 277 mV respectively. • A cell voltage of 1.7 V achieves 10 mA/cm 2 in overall water splitting. • No sludge formation in continuous more than 7 days runs, confirming excellent electrode stability.