上海科技大学知识管理系统

Revealing and regulating the intricate reaction mechanism of direct CO2 hydrogenation to higher alcohols (C2+OH), especially for the crucial C-C coupling step, is still a great challenge. Herein, the specific reaction network on Co2C and CuZnAl multifunctional tandem catalysts is elucidated by designing subtly surface adsorption-desorption reactions, in situ chemical transient kinetics, and theory calculations. The key C-C coupling step for the formation of C2+OH over the sole Co2C catalyst was the insertion of CO into R-CHx, while the reaction mechanism can be modulated to the coupling of R-CH2 and CHO with a lower energy barrier on the tandem catalyst (Co2C||CuZnAl). R-CH2 was derived from the hydrogenation dissociation of olefins and coupled with the CHO from formate hydrogenation at the Cu/ZnAl2O4 interface. Such multifunctional tandem catalysts exhibited a high space-time yield of C2+OH of 2.2 mmol g-1 h-1. This work provides an effective strategy for studying complex mechanisms, contributing to the precise design of highly efficient catalysts and the optimization of reaction pathways.