Overlaid Conductive Silver Nanowire Networks on Gas Diffusion Electrodes for High-Performance Electrochemical...

Designing selective and durable electrodes for the electrochemical CO₂ reduction reaction (eCO₂RR) requires both efficient charge transport and favorable catalytic interfaces. Conventional carbon-based gas diffusion electrodes are unstable due to electrolyte flooding, whereas flood-resistant polytetrafluoroethylene (PTFE) substrates exhibit low electrical conductivity. Herein, a stacked-electrode architecture is reported to overcome these limitations, comprising PTFE as a porous substrate, Cu₂O nanocubes as a catalyst layer, and Ag nanowire (Ag NW) networks as a current collector. The catalytic performance is highly dependent on the stacking sequence, with the PTFE/Cu₂O/Ag configuration achieving remarkable C₂₊ selectivity and durability while exhibiting electrical resistance comparable to that of carbon paper. In alkaline electrolytes, this configuration exhibits a Faradaic efficiency toward C₂₊ (FE_C2+) of 79% and stable operation for more than 50 h, significantly outperforming conventional carbon paper-based electrodes. Mechanistic studies reveal that the Ag NW networks not only ensure the coexistence of Cu(0)/Cu(I) species but also generate CO to drive tandem reactions, promoting C₂₊ production. Furthermore, it reaches an even higher FE_C2+ of 86% while maintaining long-term stability under neutral electrolytes. These findings provide a versatile strategy for the rational design of durable and selective electrodes for eCO₂RR.