Oxygen Evolution Catalysis by Manganese Oxides Resilient to Voltage Fluctuations

Renewable energy sources, such as solar and wind power, fluctuate on time scales of seconds to hours. Chemical synthesis powered by these sources requires electrocatalysts that can cope with fluctuating conditions. Here, we report an electrochemical oxygen evolution reaction (OER) system that is tolerant to voltage fluctuations through the design of catalytic pathways. By leveraging the redox chemistry of manganese oxide, we integrated the Guyard reaction (4Mn ³⁺ + Mn ⁷⁺ → 5Mn ³⁺ ) as a regeneration pathway into the catalytic cycle. Unlike other 3d-block metal catalysts, which rapidly degrade under fluctuating conditions, the constructed manganese oxide system shows resilience to voltage fluctuations by alternating between decomposition and regeneration. When the voltage is switched between 1.68 and 3.00 V repeatedly, the catalyst can maintain an OER current of 250 mA cm-2 at pH 2 for more than 2000 h, highlighting the importance of pathway design for sustainable energy conversion from intermittent renewable sources.