Constructing stable Cu-Fe5C2 interfaces for efficient syngas conversion to higher alcohols

Direct and efficient synthesis of higher alcohols (HA) from syngas over Cu-Fe binary catalysts is promising, but remaining big challenge due to the complex reaction networks and poor stability of Cu-Fe5C2 interfaces. Herein, we constructed a K-CuFe@SiO2 core–shell catalyst, which showed high HA selectivity of 51.1 %, HA yield of 14.6 % and low CO2 selectivity of 15.3 % at a mild reaction temperature of 240 °C, outperforming most of the reported advanced Cu-Fe binary catalysts. Structural characterizations confirmed that SiO2 shell played critical role in stabilizing Cu-Fe5C2 interfaces during long-term operation. Moreover, SiO2 shell could regulate the electronic interactions between K promoter and active phases, and then regulating the H2 and CO activations. Mechanism studies suggested that HA synthesis followed *CO–*CHx coupling mechanism. The balance of H2 activation, CO dissociated and non-dissociated activation was critical to realize the dynamic matching of *CO–*CHx coupling and *CH3CO hydrogenation reactions, thus maximizing HAS activity.