Synthesis of Terminal Bifunctional Aliphatic Compounds via Catalytic Oxidation of 1,6-Hexanediol Over Pt-Loaded BiVO4

Abstract

Terminal bifunctional aliphatic compounds are important intermediates for synthesis of drugs, food additives, polymers, while oxidative conversion from diols in mild conditions and the insight mechanism are rarely investigated. In this work, Pt-loaded BiVO₄ (4%Pt/S-BVO and 4%Pt/H-BVO) is proposed to be utilized for the oxidation of 1,6-hexanediol (1,6-HDO). In dark conditions, the electronic metal-support interactions between Pt and BiVO₄ and abundant oxygen vacancies (OVs) activated C-H and O₂, leading to the primary oxidation of terminal hydroxyl group of 1,6-HDO. The generated·O₂⁻ radicals enable further oxidation of aldehyde group to carboxyl group. With illumination, the photo-generated holes promoted oxidation of hydroxyl group to aldehyde group while the increased ·O₂⁻ radicals promoted the oxidation of aldehyde group to carboxyl group. The introduced heat originated from the photothermal effect and an additional heat source is supposed to boost the mass transfer of molecules and ·O₂⁻ radicals. In particular, with more abundant OVs and exposed {040} facets, more ·O₂⁻ radicals, and improved charge separation, 4%Pt/S-BVO exhibit 90% conversion of 1,6-HDO with selectivity of 98.6% to TBACs in 6 h. Those findings highlight the great promise of catalytic organics transformation by integrating solar energy to enhance the reaction efficiency.