Efficient Hydrogenolysis of C–O Bond over Pd/P-TiO2: The Generation and Role of Brønsted Acid Site Triggered by Spillover Hydrogen

The hydrogenolysis of cellulose-derived 5-hydroxymethylfurfural is essential for the production of fuels and chemicals from biomass. Herein, we fabricated a phosphorus-doped Pd/P-TiO2 catalyst for the hydrodeoxygenation of 5-hydroxymethylfurfural to 2,5-dimethylfuran. A large number of defects and electron-deficient Ti4+ sites (dTi4+) were formed by doping phosphorus into the TiO2 support, which could promote hydrogen spillover and reactant adsorption. Moreover, the spilled active hydrogen induced the formation of P–O(H)-dTi4+, which acted as a "Brønsted acidic site" to promote the activation of C–O bonds. Consequently, the Pd/P-TiO2 catalyst exhibited superb activity for the hydrodeoxygenation of 5-hydroxymethylfurfural to 2,5-dimethylfuran at mild conditions of 150 °C under 1 MPa H2.