Boosting PbO2-anode OER performance with electronically modulated W-Mn3O4 for energy-efficient zinc electrowinning

Designing a Pb-based anode with ideal oxygen evolution reaction (OER) and anticorrosion performance in highly acidic electrolyte remains a critical challenge for energy-efficient Zn hydrometallurgy. Herein, a hierarchical Pb-Sn-Ca/α-PbO 2 /β-PbO 2 -W-Mn 3 O 4 (PSC/PbO 2 -WMO) composite anode was fabricated via a sequential co-precipitation and anodic co-electrodeposition process. The W doping enables electronic optimization of the coordination environment and generates abundant oxygen vacancies in Mn 3 O 4 , collectively promoting its intrinsic conductivity and the electron-transfer rate during the OER. Moreover, the optimized PbO 2 anode modified with WMO delivers an OER overpotential of 619 mV at 50 mA cm –2 in 1.53 M H 2 SO 4 with a Tafel slope of 264.69 mV dec –1 , and no dramatic fluctuations within a 40-h stability test, simultaneously possessing an outstanding catalytic and stability property. Under simulated zinc electrowinning conditions, the cell voltage (2.71 V) and energy consumption per ton Zn (2449.46 kWh/ton Zn) for PSC/PbO 2 -WMO are reduced by 460 mV and 18.0% comparison with the commercial Pb–(0.76%)Ag alloy anode, and the current efficiency is reached up to 94.72%, exhibiting its remarkable energy-saving effect. More importantly, the accelerated service life for PSC/PbO 2 extends sevenfold to 65 h, and the lead impurity resolved in electrolyte drops to 0.325 ppm after WMO modification, further verifying its practical potential. Hence, this active-particle diffusion reinforcement approach constitutes a novel horizon on developing durable, energy-saving anodes in hydrometallurgical operations.