Synergistic electrode design for efficient CO2 electrolysis to multicarbon products at elevated temperatures

Electrocatalytic CO2 reduction reaction (CO2RR) technology holds significant industrial potential. However, when faced with elevated-temperature environments caused by industrial-scale operations, the fundamental understanding of temperature-dependent CO2RR behavior in flow cells remains elusive. This study points out that elevated-temperature operation (>333 K) presents both challenges and opportunities for multi-carbon (C2+) production. While elevated temperature enhances reaction kinetics and reduces thermodynamic energy barriers, it simultaneously induces reconstruction of Cu-based catalyst, accelerates gas diffusion electrode flooding, and promotes *CO desorption together with hydrogen evolution reaction, collectively suppressing C2+ product formation and compromising long-term reactor stability. Through rational design of hydrophobic-enhanced Pd-Cu2O/polytetrafluoroethylene (PTFE)/Ag tandem electrodes, we overcome these challenges. Leveraging thermal reduced C-C coupling barriers, the optimized electrode achieves >70% Faradaic efficiency of C2+ across industrially relevant current densities (200–1000 mA cm−2) at 348 K. This strategy converts elevated temperature adversity into a kinetic and thermodynamic advantage, boosting C2+ cathodic energy efficiency by 1.3 times compared to ambient operation, establishing a promising paradigm for industrially viable CO2 electrolysis. The electrocatalytic reduction of CO2 offers industrial potential, but elevated temperatures hinder efficient production of valuable multi-carbon compounds. Here, the authors report a synergistic electrode design for efficient CO2 electrolysis to multicarbon products at 348 K.