Mechanisms of Mo2C(101)-Catalyzed Furfural Selective Hydrodeoxygenation to 2-Methylfuran from Computation

Abstract

The selective formation of 2-methylfuran (F-CH3) and furan from furfural (F-CHO) hydrogenation and hydrodeoxygenation on clean and 4H precovered Mo2C(101) surfaces has been systematically computed on the basis of periodic density functional theory including dispersion correction (PBE-D3). The clean Mo2C(101) surface has two distinct surface sites: unsaturated C and Mo sites for the adsorption of H and furfural, respectively. The selectivity comes from the different preference of furfural hydrogenation and dissociation (F-CHO + H = F-CH2O vs F-CHO = F-CO + H) under the variation of H2 partial pressure. On the basis of the computed minimum energy path on the clean surface, microkinetics shows that high H2 partial pressure can promote 2-methylfuran formation and suppress furan formation. To verify this proposed selectivity trend of 2-methylfuran at high H2 partial pressure, the 4H precovered Mo2C(101) surface (0.25 monolayer hydrogen coverage), which provides neighboring hydrogens for promoting furfural hydr...