Composition control of CuFeZn catalyst derived by PDA and its effect on synthesis of C2+ alcohols from CO2

Abstract

Development of a low-cost and high-efficient catalyst is important for the industrialization of CO2 hydrogenation under mild conditions. Herein, the N-doped CuFeZn catalysts were prepared by using 2,6-pyridine dicarboxylic acid (PDA) as the organic ligand via co-current co-precipitation method. The optimized catalyst CuFeZn-0.7PDA exhibits an excellent catalytic performance (total alcohols selectivity of 34.75% at CO2 conversion of 10.60%, C2+OH/ROH fraction of 95.27%, and C2+ alcohols space-time-yield (STY) of 58.20 mg·mLcat−1·h−1). Combined with the characterizations of the catalysts and catalytic performance for CO2 hydrogenation, it is discovered that the enhanced catalytic performance owes to the fact that the coordination between PDA and active metal ions facilitates the electron transfer and reduction of metallic oxides, which accordingly leads to the uniform dispersion of active components. It is worth noting that N-doping is found to be related to the generation of more low-valence Cu&Fe species and oxygen vacancies, which are beneficial to the formation of C2+ alcohols.