Semi-closed synthesis of mesoporous carbon supported metal oxide nanoparticles

Common methods for preparing mesoporous carbon (MC)-supported metal oxide nanoparticles include chemical vapor deposition, sol-gel, hydrothermal, and microemulsion methods. It is necessary to first prepare carbon materials and thereafter load the metal oxide nanoparticles. In recent years, simple one-pot methods to prepare mesoporous carbon-supported metal and metal oxide nanoparticles has received a lot of attention. Inspired by the semi-closed method for preparing MC materials, in this study, we report a method for preparing MC-supported metal oxide nanoparticles in a single-step process in a muffle furnace after adding a one-step in situ synthesized precursor in a semi-closed system. The porous carbon-supported metal oxide nanoparticles prepared using this method have the advantages of a small particle size, uniform distribution, stable structure, and applicability to various metal oxides. The MoO3/MC catalysts prepared using this method exhibited excellent catalytic performance for the selective oxidation of benzyl alcohol. Only 5 mg of MoO3/MC-2 was used to convert 0.5 mmol benzyl alcohol to benzaldehyde in 2 mL DMSO with a conversion of 99% under air. The catalytic reaction is carried out at a high TON and TOF of 181 and 30.2 h−1, respectively. Furthermore, the MoO3/MC catalysts exhibited high selectivity, wide substrate universality, and excellent stability.