Rational design of an efficient Pt3Cu/TiO2 icosahedral catalyst for bio-aviation fuel production under mild conditions†

Abstract

Bio-aviation fuel is a promising alternative sustainable aviation fuel (SAF) to fossil-based jet fuels. In this study, we employed a hydrothermal method to synthesize a novel Pt₃Cu/TiO₂ icosahedral catalyst for the efficient hydrodeoxygenation (HDO) of oils and fats, enabling the highly selective production of alkanes. Characterization results confirmed the formation of Pt–Cu alloy nanoclusters in the Pt₃Cu/TiO₂ icosahedra. The catalyst exhibited excellent catalytic performance, achieving 100% conversion of oil feedstock and 91.8% selectivity towards bio-aviation fuel under mild conditions (120 °C, 0.4 MPa H₂). Additionally, the selectivity towards C₈–C₁₇ alkanes was maintained at 50.1% after cycling the Pt₃Cu/TiO₂ icosahedra for ten cycles. Density functional theory (DFT) calculations using propionic acid (PA) as a model molecule revealed that the hydrodecarbonylation reaction begins with the removal of OH* and H* from adsorbed PA on the Pt₃Cu (111) planes, forming CH₃CCO*, while the conversion of CH₃CH₂COOH to CH₃CH₂CO* and OH* was identified as the rate-limiting step.