Molybdenum carbide as catalyst in biomass derivatives conversion

The present energy dilemma in conjunction with the adverse environmental impacts caused by fossil fuel combustion motivates researchers to seek for new renewable energy with minimal CO2 footprint. As a practice pathway, it is of significance to produce biofuel and platform chemicals from sustainable biomass resources. However, the research and development of high-efficiency catalysts remain one key scientific challenge. Among the catalysts developed, transition metal carbides, especially molybdenum carbide, show promising performances on biomass-based conversion. Significant efforts have been made in past few decades on tuning the structure and electronic property of molybdenum carbide via controlling particle size and morphology, metal and nonmetal doping and vacancies, etc. The review summarizes recent developments of molybdenum carbide as catalysts in converting biomass into fuel, mainly focused on the preparation methods, the structure-dependent effects and the electronic modulation. The controllable selective cleavage of C–C, C–O and C–H bonds over modified molybdenum carbides that has been demonstrated in the conversion of biomass feedstocks is then highlighted. In addition, the possible deactivation mechanisms of molybdenum carbide are also presented in the review. This review provides systematic and fundamental information for the further design and development of molybdenum carbide for the conversion of biomass resources.