The detailed understanding of biomass conversion on well-defined model oxide catalysts provides valuable feedback for subsequent catalyst design and synthesis of desired products such as biofuels. Using state of the art EMSL capabilities (scanning probe microscopies, molecular beam scattering, oxygen plasma assisted molecular beam epitaxy) we propose to prepare model early transition metal oxide catalytic systems by depositing monodispersed (WO3)3 and (MoO3)3 clusters on selected substrates (TiO2(110), FeO(111), graphene) under well-defined ultrahigh vacuum conditions and explore their catalytic activity towards deoxygenation of ethylene and propylene glycols, glycerol, and glucose that represents basic building blocks of cellulose in biomass. The proposed work builds on our prior studies of alcohol dehydration, dehydrogenation and condensation reactions on such model catalysts. Expertise in the epitaxial growth of WO3 thin films recently developed by EMSL scientists will further allow us to broaden our supported (WO3)3 cluster studies to extended WO3 systems.