Tuning the eg∗ band broadening of the in-situ NiOOH by W doping for efficient biomass electrooxidation

5-Hydroxymethylfurfural electrooxidation reaction (HMFOR) provides a promising route for producing high-value-added compounds. It is generally believed that NiOOH is the active species in HMFOR process, but its inherently poor electron transfer ability leads to limited catalytic activity. In this work, a W doping strategy is adopted to regulate the electron transfer between NiOOH and reaction molecules. Electrochemical results show that W-doped Ni 5 P 4 -R exhibits excellent electrochemical performance for the oxidation of HMF to FDCA with the conversion of HMF and yield of FDCA both close to ∼100%. Density functional theory and in-situ characterization reveal that the introduction of W causes the distortion of NiOOH lattice, resulting in the Jahn-Teller distortion and the elimination of orbital degeneracy, thereby broadening the e g ∗ band of NiOOH. This feature is beneficial for the electron transfer between W-doped NiOOH and HMF (1.31 e − ), thereby promoting the C–H bond activation of the aldehyde group in HMF and effectively reducing the energy barrier of rate-determining step (RDS).