Electron transfer modulation diverting Mn₂O₃ catalysis in methane oxidation from combustion to selective coupling

Selectivity in oxidation reactions is governed by the targeted modification of a catalyst's surface electronic structure or charge-transfer dynamics. Oxidative coupling of methane (OCM) to ethylene is a perennial topic in catalysis, with Na₂WO₄-Mn₂O₃-based catalysts demonstrating substantial potential for industrial application. Gaining deep insight into the electron-transfer behavior responsible for redirecting methane oxidation from combustion to selective coupling on Na₂WO₄-modified Mn₂O₃ is particularly challenging. Here, we demonstrate that selectivity on Mn-based catalysts is governed not by the local active sites, but by the microscopic electron-transfer pathway during the redox cycle. The Na₂WO₄ modification fundamentally switches this pathway from bulk penetration to surface propagation over Mn₂O₃. This creates an electron-rich surface that weakens *CH₃ adsorption and selectively promotes its desorption as ·CH₃ radicals for gas-phase coupling, thereby overriding deep oxidation. Our findings provide valuable guidance for a deeper understanding of the mechanisms underlying analogous oxidation reactions.