Rationally designed hierarchical carbon supported CuO nano-sheets for highly efficient electroreduction of CO2 to multi-carbon products

Abstract

Electrochemical reduction of CO2 to value-added products is a promising path to mitigate CO2 emissions and achieve renewable energy conversion and storage. Cu-based electrocatalysts can catalyze electrochemical conversion of CO2 to multi-carbon products, however, low catalytic activity and selectivity have hindered the practical applications of this technology. Rationally designing the structure of catalysts for an improved catalytic performance is of vital importance. Here, we reported a hierarchical phenol formaldehyde resin carbon supported CuO nano-sheets (CuO/PFRC) catalyst for enhanced CO2 electroreduction to multi-carbon products. Compared with CuO nano-sheets (CuO) and commercial VXC-72r carbon black supported CuO nano-sheets (CuO/XVC), CuO/PFRC showed an enhanced catalytic activity towards multi-carbon products (mainly ethylene). The electrochemical measurements exhibited an ethylene Faradaic efficiency of 47.2 % at − 0.64 V (vs. RHE) with a high partial current density of 599 mA cm−2, which outperformed most previously reported studies. We proposed that the 3D hierarchical structure of CuO/PFRC could facilitate electron transfer process, thus promoting the catalytic activity. Further study uncovered that the hierarchical CuO/PFRC had higher CO2 adsorption capacity than control samples, which may favor to form a higher local CO2 concentration environment during CO2 electroreduction reaction and further facilitate catalytic activity promotion.