Antiflooding\nGas Diffusion Electrodes Enabled by Liquid–Solid–Liquid\nInterfaces for Durable CO<sub>2</sub> Electrolysis

Gas\ndiffusion electrodes (GDEs) show great potential to improve\nthe current densities of the industrial electrochemical carbon dioxide\nreduction reaction (eCO<sub>2</sub>RR). The triple-phase boundary\n(TPB) in GDEs is the key for promoted reaction kinetics, yet such\na reaction interface typically suffers from rapid degradation due\nto electrolyte flooding and salt precipitation. Herein, we demonstrate\nthat a GDE modified with liquid perfluorocarbon (PFC) would notably\nprolong the lifespan of the GDE with a Bi catalyst in flow-cell electrolyzers.\nPFC with superhydrophobicity and high CO<sub>2</sub> solubility would\nconstruct a liquid–solid–liquid reaction interface that\nprevents the intrusion of electrolytes into the microporous layer\n(MPL) without hampering the mass transport of CO<sub>2</sub>. Our\nwork demonstrates an effective strategy to construct a robust and\nefficient electrochemical reaction interface for the eCO<sub>2</sub>RR with improved stability for potential industrial applications.