Synergy of metallic Co and oxygen vacancy sites in Co/Ce-MOF catalysts for efficiently promoting lignin derived phenols and macromolecular lignin hydrodeoxygenation.

The enhanced utilization of biomass-derived chemicals for the generation of high value aromatics through an advanced catalytic strategy has captured considerable attention within the realm of eco-friendly manufacturing. This work presented four innovative three-dimensional rod-shaped mesoporous Ce-based MOF materials, which were coupled with a H-donor solvent to facilitate vanillin hydrodeoxygenation and macromolecular lignin. Under the optimized conditions (30 mg CoCe@C catalyst, 2 MPa N2 pressure, 15 mL isopropanol, 190 °C, and 5 h), the CoCe@C catalyst achieved nearly complete conversion of vanillin and demonstrated 87.8 % selectivity in the hydrogen-donor solvent. The characterization findings suggested that the synergy between metallic Co and oxygen vacancy sites enabled the effective activation of CHO group in vanillin, leading to formation of reactive product MMP. In addition, the optimal CoCe@C catalyst could also achieve macromolecular lignin hydrodeoxygenation to obtain high yield of lignin oil products with narrower molecular weight distribution. This study presented a viable approach for the concurrent utilization of lignin derivatives in the generation of high value fuels and chemicals.

Boosting 5-Hydroxymethylfurfural Electrooxidation by Porous Biochar via Loading Numerous Surface-Exposed Cobalt Phosphonates.

The electrooxidation of 5-hydroxymethylfurfural (HMF) into 2,5-furandicarboxylic acid (FDCA) demonstrated its unique superiority, not only in reducing overpotential and improving energy conversion efficiency for green hydrogen production but also in utilizing abundant biomass resources and producing high-value-added chemicals. However, designing highly efficient electrocatalysts for HMF electrooxidation (HMF-EOR) with low cost and high performance for large-scale production remained a huge challenge. Herein, we introduced an easy one-step activation process to produce P-doped porous biochar loaded with multiple crystal surfaces exposed to CoP2O6 catalysts (CoP2O6@PC), which exhibited outstanding electrooxidation performance. To achieve a current density of 50 mA cm-2, only a low overpotential of 200 mV was needed for the electrooxidation of HMF in 1.0 M KOH + 10 mM HMF. This performance far surpassed that of other similar materials. CoP2O6@PC exhibited outstanding HMF-EOR performance with high conversion (nearly 100%), selectivity (97.1%), faradaic efficiency (95.3%), and robust stability. This work represents a promising strategy to fabricate macroscale and low-cost HMF-EOR electrocatalysts and achieve potential industrial applications of HMF-EOR.