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

Abstract

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 bond length, which eventually modulate the local atomic structural environment and result in enhanced catalytic activity. Moreover, the entrapped bimetallic nanoparticles with carbon shells in Cu–Pd@C-B catalyst further protect the active catalytic site from migration, aggregation, and leaching during hydrogenolysis reaction and improve the stability of the catalyst.

A Non‐Noble Monometallic Catalyst Derived from Cu–MOFs for Highly Selective Hydrogenation of 5‐Hydroxymethylfurfural to 2,5‐Dimethylfuran

“…Chitra et al. reported a copper‐based catalyst derived from MOFs and loaded with Pd by impregnation to obtain excellent catalytic activity with a DMF yield of 96.5% . Although the noble metal's adding effectively increases the activity of copper catalysts, the cost still too high and not reasonable.…”

Effects of metal promoters in bimetallic catalysts in hydrogenolysis of lignin derivatives into value‐added chemicals

“…In general, the geometric effect is always accompanied by the electronic effect to improve the catalytic performance in biomass conversion over the bimetallic catalysts [38,92] . For example, Ni 3 Ga/SiO 2 catalyst exhibited higher benzene yield in the HDO of anisole and remarkably reduced H 2 consumption in comparison with the Ni/SiO 2 catalyst, which was mainly attributed to the geometric and electronic effect between Ni and Ga metals, [93] from which a charge transfer from Ga to Ni increased the electron density of Ni, while the Ni ensembles became smaller due to the isolation of Ga. That result was consistent with Zhao et al [94] .…”

MOFs Derived Catalysts Prepared by Pyrolysis for Hydrogenation of Bio‐Based Furfural: A Mini‐Review

“…Sarkar et al prepared CuÀ Pd@C by pyrolysis based on interface and alloy effect. [93] CuÀ Pd alloy nanoparticles encased in carbon shell could avoid migration, sintering or leaching during hydrogenation of furfural ( Figure 12). Dong et al obtained Pd/MIL-101(Fe)-NH 2 by after amino functionalization of MIL-101(Fe) and supported with precious metal Pd, which could selective hydrogenate a variety of aldehydes (Figure 13).…”