MoCx species embedded in ordered mesoporous silica framework with hierarchical structure for hydrogenation of naphthalene

Abstract

An integrated route to accomplish the incorporation of MoCx species into ordered mesoporous silica framework (OMSF) was presented. The MoVI–melamine hybrids were used as the single-source precursors for molybdenum carbides and participated in the assembling process of the silica building blocks that gave rise to the OMSF preform. The pore diameter and the volume of the resulting MoCx@OMSF samples were characterized by gradually increasing with the amount of the added hybrids, which, among other things, maximized the space inside the silica tubes at the highest Mo loading. The thermal decomposition of the P123 micelles with the catalysis of the in situ formed Mo species generated the tube-like carbon framework within the silica tubes. The finely incorporation of the MoCx species to the carbon framework was supposed to account for the good stability of the carbide phase in the hydrogenation of naphthalene. Ultra-high selectivity of ∼98% to tetralin was achieved on the MoCx@OMSF samples thanks to the moderate hydrogenating ability of the carbide phase, indicating potential use of molybdenum carbide based composites as low-cost selective catalysts for industrially relevant partial hydrogenations.