Combining Nanoconfinement in Ag Core/Porous Cu Shell Nanoparticles with Gas Diffusion Electrodes for Improved...

Bimetallic silver-copper electrocatalysts are promising materials for electrochemical CO₂ reduction reaction (CO₂RR) to fuels and multi-carbon molecules. Here, we combine Ag core/porous Cu shell particles, which entrap reaction intermediates and thus facilitate the formation of C₂₊ products at low overpotentials, with gas diffusion electrodes (GDE). Mass transport plays a crucial role in the product selectivity in CO₂RR. Conventional H-cell configurations suffer from limited CO₂ diffusion to the reaction zone, thus decreasing the rate of the CO₂RR. In contrast, in the case of GDE-based cells, the CO₂RR takes place under enhanced mass transport conditions. Hence, investigation of the Ag core/porous Cu shell particles at the same potentials under different mass transport regimes reveals: (i) a variation of product distribution including C₃ products, and (ii) a significant change in the local OH^- activity under operation.