Nanocurved electric-field-induced optimal catalyst loading for carbon dioxide electroreduction

Abstract

As a simple way to enhance catalytical performance, it has long been believed that catalyst loading increases the number of sites available for reaction. The overall reaction rate will increase and saturate eventually as catalyst loading increases. Here, we report a counterintuitive optimal catalyst loading for electrocatalytic carbon dioxide reduction (eCO_{2}R) on nanocatalysts. Numerical analysis based on a comprehensive kinetic model reveals that nanocurved electric field (NEF) resulted from the comparable size of nanocatalysts and the electric double layer can essentially affect eCO_{2}R. While NEF induces extra mass transfer raising the overall reaction rate for low catalyst loading, such extra mass transfer is sharply reduced due to the overlap of NEF for high catalyst loading. These findings challenge the conventional physical picture of loading-dependent overall catalytical performance, and provide a new concept for design of nanocatalysis.