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Selective removal of oxygen from biomass-derived polyols is critical toward bridging the gap between biomass feedstocks and the production of commodity chemicals. In this work, we show that earth-abundant molybdenum oxide based heterogeneous catalysts are active, selective, and stable for the cleavage of vicinal C–O bonds in biomass-derived polyols. Catalyst characterization (Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS)) shows that partially reduced MoOx centers are responsible for C–O bond cleavage and are generated in situ by hydrogen dissociated atoms over palladium (Pd) nanoparticles. We find that the support, TiO2, facilitates communication between the hydrogen dissociating metal and dispersed MoOx sites through hydrogen spillover. Reactivity studies using a biomass-derived model substrate (1,4-anhydroerythritol) show the effective removal of vicinal hydroxyls over MoOx-Pd/TiO2 producing tetrahydrofuran with >98% selectivity at 29% conversion. Catalyst stability is demonstrated upon cycling. These studies are critical toward the development of low-cost heterogeneous catalysts for sustainable hydrodeoxygenation of biobased polyols to platform chemicals. 

There is a critical need for sustainable routes to produce hydrogen peroxide, H2O2. A promising approach involves direct synthesis from molecular hydrogen and oxygen at (sub)ambient temperatures using unmodified supported Pd catalysts, which are limited by low selectivities. Controlling the environment of Pd active sites via surface ligands is shown to enhance selectivity. Trends among a myriad of surface ligands (i.e., phosphines, thiols, weakly bound molecules) suggest that those containing H-bonding groups lead to the highest H2O2 production, potentially by affecting reaction energetics via H-bonding with key intermediates. These insights lay the groundwork for ligand design to achieve the optimal catalyst performance for H2O2 synthesis.