Tuning charge transfer of Pt cluster by support defects in Pt/TiO2 for photocatalytic conversion of fatty acid into diesel-like alkane

Abstract

Efficient deoxygenation for the bio-derived fatty acid is paramount to producing diesel-like alkane and usually requires harsh reaction conditions. Here, we reported an efficient conversion system for the photocatalytic conversion of fatty acid over Pt/TiO2 catalysts and acid conversion higher than 99.0% (yield nearly 84.5%) under the mild conditions 30 °C, 0.1 MPa H2, and 365 nm light. X-ray photoelectron spectroscopy (XPS) and Density Functional Theory (DFT) calculations suggest that the oxygen vacancies TiO2 can achieve the charge transfer from TiO2 support to Pt clusters. The electron-rich Pt cluster can promote hydrogen spillover to form a hydrogen-rich surface. Thus, it leads to the photo-decarboxylation Cn-1 alkyl radical being amenable to proton hydrogenation to produce Cn-1 alkane. Detailed characterization demonstrates that 0.50 wt% Pt/TiO2 has superior photocatalytic performance. Introducing the Pt atoms can promote the formation the oxygen vacancies and reverse charge transfer, which determines the acid adsorption and conversion mechanism.