CuAg nanoparticle/carbon aerogel for electrochemical CO2 reduction

The electrochemical carbon dioxide reduction reaction (eCO2RR) is a promising technology that uses electrical energy to catalytically reduce greenhouse gas-CO2, converting CO2 into high value-added products such as hydrocarbons and alcohols. However, due to the complexity of the eCO2RR, the activity and selectivity of the eCO2RR is highly dependent on the intrinsic catalytic activity of a catalyst with mass transportation-favorable morphology. Herein, silk fibroin-derived carbon aerogels (CAs) loaded with small amounts of Cu and Ag nanoparticles were synthesized. Based on the molar content of Cu, the catalysts were labeled SF-CuAg/CA-N (N = 20%, 40%, 60%, 80%). Among them, SF-CuAg/CA-40% showed a good FECO of 71% at −1.26 V vs. a reversible hydrogen electrode (RHE), and a significant current density of −15.77 mA cm−2 towards CO at −1.06 V vs. RHE, which is close to 2.6, 2.53 and 2.71 times those of SF-CuAg/CA-20% (−6.02 mA cm−2), SF-CuAg/CA-60% (−6.24 mA cm−2) and SF-CuAg/CA-80% (−5.82 mA cm−2). The SF-CuAg/CA-N composite materials prepared in this study provide new ideas for the design of highly efficient electrocatalysts for the eCO2RR.