Regulating the electronic property of iron catalysts for higher alcohols synthesis from CO2 hydrogenation

Abstract

The electronic property of a catalyst is crucial to the generation of key reaction intermediates for targeted synthesis. Herein, we reported a strategy by modifying iron catalysts with sulfate and alkali metal (Li, Na, or K) to regulate the electronic property and optimize the reaction pathways for CO2 hydrogenation to higher alcohols. The characterizations demonstrated the influencing relationship between the electronic property of iron catalysts and the catalytic capabilities for CO dissociation, non-dissociated CO activation and catalytic hydrogenation, which were critical to selective synthesis of higher alcohols. Na-S modification was proven more effective to balance the multiple capabilities required for higher alcohols synthesis and the NaS-Fe catalyst gave a higher C2+OH yield in CO2 hydrogenation. DFT calculations further validated the advantage of Na-S modification from the aspects of CO adsorption and C−C coupling. This strategy provides more flexibility in site regulation and applies to catalyst design for many reactions.