Plastron effect enhanced electrochemical CO2 reduction activity over hydrophobic three-dimensional nanoporous silver.

Abstract

The electrochemical reduction of CO2 on catalyst surfaces is hindered by the inefficient mass transfer of CO2 in aqueous solutions. In this study, we employed an electrochemical reduction approach to fabricate a hydrophobic three-dimensional nanoporous silver catalyst with a plastron effect, aiming to enhance the CO2 diffusion. The resulting catalyst exhibited an exceptional performance with the FECO peaking at 95% at -0.65 V (vs. RHE) and demonstrated remarkable stability during continuous electrolysis for 48 hours. Control experiments, together with Tafel analysis, EIS measurements, and contact angle results, confirmed that the notable enhancement of performance was attributed to the hydrophobic porous structure that facilitated efficient storage and rapid mass transfer of low-solubility CO2 gas reactants.