Why are Ru/TiO2 catalysts so selective for direct deoxygenation?

Graduate student Byeongjin Baek’s computational work on elucidating the mechanism of direct deoxygenation of phenolic compounds on Ru/TiO2 catalysts has resulted in a new understanding of the roles of the support and the ruthenium metal nanoparticle. We find that for the selective C-OH cleavage to occur, it is necessary that the support can provide a proton to weaken the C-O bond. In turn, the proton must be regenerated, which can occur by heterolytic H2 splitting across the Ru/TiO2 interface (see figure). Our results were published in ACS Catalysis and are important to further improve deoxygenation catalysts and enable a hydrogen-efficient upgrade of bio-oil into transportation fuel. Byeongjin’s DFT work at UH was supported by a DOE Early Career Award.