Chao Lin, Ji-Li Li, Shuai Yang, Tiejun Zhao, Qiang Kang, Xiaotong Wu, Xiaopeng Li*, Zheng Jiang, Ye-Fei Li*, Zhi-Pan Liu, Wei Luo, and Jung-Ho Lee*
Abstract Replacing the oxidation of water with the electrocatalytic oxidation of methanol is an attractive route to level the cost of H2 production with value-added chemicals; however, this reaction has been notoriously known for quickly poisoning electrocatalysts and/or sliding into complete oxidation, thereby producing CO2. Here, we report an acid-stable Ru metal atom array that is supported by MnO2 nanofibers (Ru-MAC/MnO2) for the electrocatalytic valorization of methanol to methyl formate (MF). The productivity of MF is 10 to 100 times higher than those reported in thermal- and photocatalytic processes at commercially viable current densities. Our experimental and simulation results demonstrate that the atom array possesses long-term electrochemical stability and prefers the MF pathway without generating *CO intermediates. The synergistic intersite metal–metal and metal–support electronic interactions endow Ru-MAC/MnO2 with outstanding structural stability toward large-current-density methanol electrolysis.