Micro-nickel doping regulates the surface electron and structure of materials for optimizing biomass upgrading

Electrocatalytic oxidation of 5-hydroxymethylfurfural (HMFOR) is an effective way to realize the upgrading of high value-added chemicals coupled with electrolytic water to produce hydrogen under green conditions. However, the oxygen evolution reaction competition of the anodic water decomposition of HMFOR electrocatalysts at high current densities hinders the production efficiency of 2, 5-furan dicarboxylic acid (FDCA). Although Cu has excellent electrical conductivity and small molecule affinity, it does not perform well in OER. The catalytic activities of Co and Ni in the electrochemical oxidation of small organic molecules and OER were significant. By optimizing the electronic structure and morphology of Cu, Co, and Ni, the competitive reaction of OER can be effectively inhibited, and the catalytic efficiency of HER can be strengthened. Then, we have successfully constructed a micro-Ni-doped Co phosphide grown on Cu foam (Ni m CoP/CF) with an optimized interfacial structure for adsorption and conversion of reactants. At 1.43   V vs. RHE, Ni m CoP/CF achieves high current density (100   mA   cm -2 ) and selectivity for FDCA. The Co site at Ni optimized interface was identified as the catalytic center for OH⁎ adsorption by electrochemical tests and Density Functional Theory calculations, and the synergistic adsorption between Ni-doped Co 2 P and Cu 3 P interfaces greatly enhanced the adsorption of HMF, further promoting the catalytic conversion of HMF to FDCA. This work has guiding significance for the selective upgrading of high value-added chemicals hydrogen evolution through interfacial regulatory strategies for micro-metal doping.