Insight into the Catalytic Mechanism of CuCeOx/C for the Hydrogenation of 5-Hydroxymethylfurfural to 2,5-Bis(hydroxymethyl)furan

2,5-Bis(hydroxymethyl)furan (BHMF) is a diol with great potential for polyester monomer. Herein, an efficient CuCeOx/C x /C was synthesized using carboxymethyl cellulose (CMC) as a sacrificial template for the catalytic hydrogenation of 5-hydroxymethylfurfural (HMF) to BHMF. Under the optimal conditions, the BHMF yield of over 98 % was obtained. The unique catalyst reactivity originated from the synergism of the rich oxygen vacancies (OV) V ) and Cu2+/Cu0-species 2+ /Cu 0-species on the catalyst surface. The incorporation of CeOx x as support strengthened the electrophilicity for the Cu2+-species, 2+-species, which was beneficial to the adsorption of the negative aldehyde groups in HMF. The Cu2+ 2+ and Cu0-species 0-species on the CuCeOx/C x /C surface were responsible for adsorbing HMF and activating H2. 2 . The selective adsorption of the aldehyde group in HMF via the oxygen-terminal through a vertical or tilted configuration ensured the efficient hydrogenation of HMF to BHMF.