Dynamic Modulation of H+–H– Pairs over Oxygen-Vacancy-Engineered CoP–CoLaO Interfaces for Selective Cascade Conversion of Furfural to 1,4-Pentanediol

Abstract

The direct production of linear 1,4-pentanediol (1,4-PDO) from biomass-derived furfural remains challenging. Conventional metal-acid catalysts tend to cause excessive hydrogenation of the furan ring or acid-driven rearrangement to cyclopentanone, resulting in poor selectivity. Herein, we construct CoP–CoLaO@C catalysts with abundant oxygen vacancies via sequential reduction, mild oxidation, and phosphidation of a La-doped ZIF-67 precursor. The resulting catalyst features CoP nanoparticles interfaced with La3+–Ov–Co2+ interface. At 100 °C and 3.0 MPa H2, CoP–CoLaO@C delivers a 90.3% yield of 1,4-PDO from furfural (FFA), following a hydrogenation-etherification–hydrogenolysis–hydrolysis–hydrogenation cascade. Kinetic analysis, isotope experiments, in situ diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, and near-ambient-pressure X-ray photoelectron spectroscopy (XPS) establish that H2 is dissociated on CoP and transferred to the La3+–Ov–Co2+ interface through hydrogen spillover. At this polarized interface, coadsorbed H2O captures protonic hydrogen to form H––La3+–Ov–Co2+–O–H+ species. These paired species supply transient Brønsted acidity for furfuryl alcohol etherification and promote the C–O hydrogenolysis of 2-ethoxymethylfuran via an SN2 mechanism. The results highlight the important role of oxygen-vacancy interfaces in regulating hydrogen transfer during the conversion of FFA to linear diols.