Evolution of Cu single atom catalysts to nanoclusters during CO2 reduction to CO

We synthesized Cu single atoms embedded in a N-doped porous carbon catalyst with a high Faradaic efficiency of 93.5% at -0.50 V (vs. RHE) for CO2 reduction to CO. The evolution of Cu single-atom sites to nanoclusters of about 1 nm was observed after CO2 reduction at a potential lower than -0.30 V (vs. RHE). The DFT calculation indicates that Cu nanoclusters improve the CO2 activation and the adsorption of intermediate *COOH, thus exhibiting higher catalytic activity than CuNx sites. The structural instability observed in this study helps in understanding the actual active sites of Cu single atom catalysts for CO2 reduction.

Automated summary

In this study, Cu single atoms embedded in N-doped porous carbon catalyst were synthesized, exhibiting a high Faradaic efficiency of 93.5% for CO2 reduction to CO at -0.50 V (vs. RHE). The evolution of Cu single atoms to nanoclusters was observed after CO2 reduction at a potential lower than -0.30 V (vs. RHE). DFT calculation showed that Cu nanoclusters improved CO2 activation and the adsorption of intermediate *COOH, resulting in higher catalytic activity compared to CuNx sites. The observed structural instability provides insights into the actual active sites of Cu single atom catalysts for CO2 reduction.