Integration of Interfacial and Alloy Effects to Modulate Catalytic Performance of Metal–Organic-Framework-Derived Cu–Pd Nanocrystals toward Hydrogenolysis of 5-Hydroxymethylfurfural

Selective formation of 2,5-dimethylfuran (DMF) by hydrogenolysis of lignocellulosic biomass-derived 5-hydroxymethylfurfural (HMF) is highly desirable for renewable liquid biofuel production. Here we have synthesized Cu–Pd bimetallic nanoparticles embedded in carbon matrix (Cu–Pd@C) by simple pyrolysis of Pd-impregnated Cu-based metal–organic frameworks (MOFs) followed by conventional hydrogenation route. It was found that Cu–Pd@C-B (solid–gas-phase hydrogenation route) with Cu–Pd bimetallic alloying exhibited brilliant catalytic performance at 120 °C under 15 bar H2 pressure to produce liquid DMF biofuel with 96.5% yield from HMF as compared with the Cu–Pd@C-A catalyst (liquid phase hydrogenation route), which gave 46.4% yield under the same conditions. X-ray photoelectron spectroscopy (XPS) and X-ray absorption near-edge structure (XANES) studies reveal that Pd in Cu–Pd@C-B catalyst is electronically promoted by Cu with the unique intrinsic synergy of increased Pd–Pd bond distance and decreased Cu–Cu bon...