Novel Stable Co-SnO2 Composite Electrocatalysts With Low Oxygen Evolution Potential

Proton exchange membrane (PEM) water electrolysis offers a sustainable route for hydrogen production, yet the reliance on costly noble metal-based anodes hinders scalability. Tin dioxide (SnO ₂ ) emerges as a promising alternative due to its acid stability, but its high oxygen evolution potential (OEP) limits practical application in hydrogen production via water electrolysis. Here, we address this challenge by incorporating cobalt (Co) into SnO ₂ to create a composite electrocatalyst. The optimized Co-SnO ₂ catalyst with a tin-to-cobalt mass ratio of 3:1 exhibits a significantly reduced OEP (1.5 V vs. RHE) and an overpotential of 186 mV at 10 mA cm ^− 2 in acidic media, outperforming undoped SnO ₂ . Stability tests reveal a lifespan exceeding 12 hours at 100 mA cm ^− 2 , a threefold improvement over pure SnO ₂ . This work underscores the potential of Co-doped SnO ₂ as a cost-effective, durable anode catalyst for PEM electrolyzers.