Direct synthesis of higher alcohols from syngas over modified Mo₂C catalysts under mild reaction conditions

Direct syngas conversion to higher alcohols with high selectivity under mild reaction conditions has attracted much attention but still remains a great challenge. Herein, we reported that the addition of Rh and K promoters to Mo2C (RhK/Mo2C) can significantly increase alcohols selectivity to 44.4% under a mild reaction pressure of 1 MPa. Mechanism study illustrated that interface sites between Rh and Mo2C promoted by K effectively contributed to the improved catalytic performance. The K promoter not only promoted the dispersion of Rh with a partial Rh delta+ state under working conditions but also suppressed further hydrogenation of olefins. In addition, the highly dispersed Rh delta+ species increased the concentration of non-dissociated CO* intermediates and greatly improved the coupling ability of CO and alkyl species to form alcohols. This work provides a promising strategy to design efficient heterogeneous catalysts at low pressure for higher alcohols synthesis over Mo2C-based catalysts.