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

Abstract

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^δ+ state under working conditions but also suppressed further hydrogenation of olefins. In addition, the highly dispersed Rh^δ+ 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.