Improving Interfacial Electron Transfer via Tuning Work Function of Electrodes for Electrocatalysis: From Theory to Experiment

Interfacial electron transfer (IET) at the metal–solution interface is known as a rate-determining step for many electrocatalytic reactions. Hitherto, there is still lack of physical insight into the IET process, as well as an experimental physical quantity directly linked to the IET rate. In this work, we propose that the work function can serve as an indicator for the IET rate of same metals such as silver quantum mechanical analysis demonstrates that a decrease in the work function can dramatically enhance the IET process. To experimentally verify this hypothesis, three different silver catalysts are prepared for CO2 electroreduction. The experimental results confirm that reducing work function of silver catalysts can improve the IET, according to the change of the Tafel slope. Resultantly, the silver catalyst with smaller work function achieves higher activity and selectivity for CO production. This study demonstrates a promising strategy to enhance the performance of same metal catalysts through tuning its work function.