Construction of Cu–Re–Ox rich interfaces for the catalytic hydrogen transfer of furfural

Abstract

The transformation of furfural into a variety of high-value-added products attracts a lot of industrial interests and provides a new strategy for the replacement of fossil fuels by available renewable resources. In our recent work, we designed a series of highly efficient and stable catalysts using a one-pot sol–gel method to configure a well-defined ternary Cu–Re–AlO_x system. A reversed loading model is used to deposit ReO_x clusters on Cu nanoparticles, supported and dispersed on an alumina bulk phase. The Cu–Re–O_x rich interfaces with strong bimetallic synergy is evidenced by electron transfer from Cu atoms to ReO_x, which can be regulated using the surface arrangement of Re atoms. Both operando-FTIR spectra and DFT calculations illustrate the furfural hydrogenation mechanism proceeding via the dehydroxylation reaction pathway to produce 2-methylfuran. Cu₅Re/Al₂O₃ with an appropriate Cu/Re atomic ratio exhibits the promoted exposure of active Cu centres and reactant-activation behaviour, resulting in an ultra-fast reaction rate of 5.98 mol_2-MF mol_M⁻¹ h⁻¹ with a low activation energy barrier at only 190 °C. This work highlights the utility of a Cu–Re-based catalytic system for the selective hydrogenation of furfural by one-pot synthesis.