Electrochemical Water Splitting Using MnO2 and TiO2 for H2 Generation

Hydrogen represents a clean and powerful energy carrier, but large-scale production remains limited by the high cost of water-splitting catalysts. While noble metals offer excellent activity, their expense restricts commercial viability. Transition-metal-based catalysts provide a promising alternative by lowering reaction energy barriers at reduced cost. This study investigates MnO₂ combined with RuO₂ and TiO₂ as potential oxygen evolution reaction (OER) catalysts. Under alkaline conditions, MnO₂ performance improved markedly when integrated with Ru, forming a Ru–MnO₂ hybrid catalyst. Among all tested samples, pure MnO₂ and commercial IrO₂ exhibited the lowest OER activity, whereas Ru–MnO₂ hybrids (2 mg, 5 mg, and 10 mg loadings) achieved the highest performance. The enhanced electron transfer and favorable surface properties of the Ru–MnO₂ hybrids highlight their potential for efficient and sustainable hydrogen generation.