Transformations of Biomass, Its Derivatives, and Downstream Chemicals over Ceria Catalysts

In the past two decades, on account of the energy and environmental crisis brought by the decline in fossil resources, price volatility, and climate change, the high-value utilization of biomass feedstocks has gradually attracted widespread attention. Catalytic conversion of biomass usually involves tandem activation and cleavage of C-C and C-O bonds. Some steps occur in the aqueous phase and demand catalysts of high water resistance. Water-resistant ceria with redox and acid-base synergistic catalytic sites has attracted great interests particularly for biomass upgradation. The reversible Ce3+/Ce4+ redox pairs and the existence of oxygen vacancies improve its redox ability and thus catalytic activity. Besides, the acid-base properties enable its use in acid-base catalytic reactions. The strength or concentration of acid-base sites is tailorable. The water-tolerance character is unique and thus can be employed in the conversion of dilute aqueous biomass solutions. In this Perspective, we summarize the latest research progress in the high-value utilization of biomass feedstocks, including biomass raw materials, platform molecules originated from biomass as well as its derivatives and downstream chemicals over pure CeO2, doped CeO2, and CeO2-supported metal catalysts.