Photocatalytic oxidation of thiophene on BiVO4 with dual co-catalysts Pt and RuO2 under visible light irradiation using molecular oxygen as oxidant

Thiophene is one of the main sulfur-containing compounds in gasoline and difficult to be oxidized with the conventional oxidative processes. Herein for the first time we report that thiophene can be oxidized to SO3 on BiVO4 co-loaded with Pt and RuO2 co-catalysts (denoted as Pt-RuO2/BiVO4) under visible light irradiation with molecular oxygen as oxidant. The high activity of the catalyst can be achieved by only loading as low as 0.03 wt% of Pt and 0.01 wt% of RuO2 as dual co-catalysts on BiVO4. ESR measurements give the evidence that the active oxygen species ((OH)-O-center dot and O-2(center dot-)) generated by photocatalytic processes are involved in the photocatalytic oxidation of thiophene. The considerable enhancement of photocatalytic activity can be attributed to the simultaneous presence of the reduction and oxidation co-catalysts which are beneficial for the efficient separation and transfer of the photo-generated electrons and holes.