Suppression of hydrogen evolution reaction in CO2 reduction by functionalizing Ag-decorated Si electrode with phthalocyanine

The photo-assisted electrochemical CO 2 reduction reaction (CO 2 RR) toward CO stands as a highly promising pathway for addressing environmental challenges and produces valuable chemicals. In this study, a novel pl-Si/Ag/Pc electrode was developed with the surface enveloped by an amorphous phthalocyanine overlayer. The pl-Si/Ag/Pc electrode has gained recognition as a catalyst of exceptional quality, displaying superior activity, selectivity toward CO, and stability. A synergistic mechanism has been revealed from experimental results that Ag served as active centers for CO 2 RR, Pc facilitated CO 2 adsorption and suppressed the competing HER reaction. Functionalizing the surface of electrode with Pc enhanced the CO selectivity (FE CO at 90.8 % under −1.5 V vs RHE) during the CO 2 RR process and reduced the cost in following product separation procedures. This study presents an uncomplicated yet effective approach for formulating durable and discerning electrocatalysts dedicated to the utilization of CO 2 .