Introducing Fe Into Cu-Based Catalyst to Boost Electrocatalytic Hydrogenation of 5-Hydroxymethylfurfural.

Converting biomass-derived 5-hydroxymethylfurfural (HMF) into high-valued 2,5-dihydroxymethylfurfural (DHMF) via electrocatalytic hydrogenation (ECH) technology has been widely regarded as one of the most economical and eco-friendly routes. The high selectivity and activity depend on the reasonable regulation of the adsorption and activation of adsorbed hydrogen (H*) and HMF on the surface of the electrocatalyst. Herein, we report nanoflower-like CuFe-based electrocatalysts on copper foam (CF) substrates (CuFeO/CF). DHMF was achieved on the optimal CuFeO/CF with a selectivity of 93.3 % and a yield of 90.1 %. The H*, HMF and product were observed by in situ attuned total reflection Fourier transform infrared spectroscopy (ATR-FTIR). Moreover, in situ Raman spectra discloses the reconstruction of catalyst into CuFe-bimetal with low valence state. Density functional theory (DFT) calculations demonstrate that introducing Fe plays a role in regulating the electronic structure of Cu sites, which facilitate the generation of H* and adsorption of HMF, thus hampering the occurrence of dimerization. This study provides an innovative idea for the rational design of non-precious bimetallic electrocatalysts for ECH to produce high-valued chemicals.