Electrochemical Conversion of Methane to C₂₊ Hydrocarbons and Hydrogen

Catalytic methane (CH 4 ) upgrading to C 2+ products has attracted widespread interest. However, non‐oxidative coupling and oxidative coupling of CH 4 are limited by coking and over‐oxidation, respectively. In this work, we propose an efficient and stable CH 4 conversion system in a solid oxide steam electrolyzer, enabling the simultaneous production of C 2+ hydrocarbons and H 2 . Furthermore, through various in situ characterizations, we reveal a gaseous ·CH 3 radical coupling mechanism underlying the electrochemical CH 4 conversion. These findings pave the way for the efficient design of the electrode for anodic CH 4 coupling reactions in a solid oxide electrolyzer and establish a new framework for atom‐efficient strategies for CH 4 upgrading.