Catalytic Tandem CO 2 Hydrogenation and Hydroformylation for High-Yield Synthesis of C 2+ Alcohols

CO 2 hydrogenation to C 2+ OH is highly attractive but remains a great challenge due to low C 2+ OH productivity and poor catalyst stability. Herein, we report efficient CO 2 hydrogenation to C 2+ OH over a Ni- and K- co -modified Fe-based catalyst (1Ni-4K/Fe), achieving a promising space-time yield (STY) of 317.0 mg/g/h and catalytic stability over 300 h. Systematic investigations reveal that the addition of Ni promotes the formation of surface alkyl intermediates, while K mitigates the undesired deep hydrogenation of these alkyl intermediates. Both effects facilitate coupling between *CO and *CH x, thereby enhancing the production of C 2+ OH. Moreover, the synergistic effect between K and Ni expedites the formation of Fe 5 C 2 and the recarburization of in situ oxidized Fe species during the reaction, resulting in enhanced stability of the 1Ni-4K/Fe catalyst. Additionally, by introduction of Rh 1 /POP (for the hydroformylation of olefins to aldehydes) and Cu@SiO 2 (for the hydrogenation of aldehydes to alcohols) catalysts to establish a 1Ni-4K/Fe||Rh 1 /POPs||Cu@SiO 2 triple-tandem system, an excellent C 2+ OH STY of 980.5 mg/g/h can be achieved, along with a C 2+ OH selectivity of 55.0% and a high proportion of C 3+ OH (75.6%) in the alcohol products.