Ce-Doping Rather Than CeO2 Modification and Their Synergistic Effect: Promotion from Ce Species in the Electrocatalytic Oxidation of 5-Hydroxymethylfurfural Over NiFe–LDH

Electrocatalytic oxidation of 5-hydroxymethylfurfural (HMFOR) is an effective route to produce value-added chemicals with low energy consumption. In this work, efficient electrocatalysts are prepared by varying the amount of Ce doping and CeO 2 modification on NiFe layered double hydroxide (NiFe–LDH) nanosheets supported on carbon cloth (CC). Through Ce doping and heterogeneous interface construction, the electronic structure and coordination chemistry of NiFe–LDH are greatly changed. Compared to CeO 2 modification and the synergistic effect of Ce-doping and CeO 2 modification, CC@NiFeCe(3%)-LDH with only Ce-doping show excellent charge transfer ability, higher HMF conversion (95.73%), 2,5-furandicarboxylic acid (FDCA) selectivity (93.31%), and Faraday efficiency (99.47%) at only 1.44 V RHE . Density-functional theory calculations and X-ray fine structure spectroscopy demonstrate that Ce doping, compared with CeO 2 modification and their synergistic effects, significantly facilitates the electron transport and optimizes intermediate adsorption by effectively lowering the activation energy for the transformation of 5-formyl-2-furancarboxylic acid (FFCA) and encourage the conversion of FFCA to FDCA. Overall, this work systemically investigates the HMFOR behaviors of CC@NiFe–LDH under Ce doping, CeO 2 modification, and their synergetic effect, which provides some guidance on the development of high-performance electrocatalysts for HMFOR performance.