Promoted visible-light-driven oxidative desulfurization of thiophene over mesoporous PdO-incorporated BaSnO3 nanocomposites

Abstract

An emerging method for removing sulfur-containing materials like thiophene, known as photocatalytic oxidative desulfurization, utilizes moderate temperatures and pressures without the use of H2 gas, unlike hydrodesulfurization. Here, we used a hydrothermal technique to produce Barium stannate nanoparticles (BaSnO3 NPs). A PdO/BaSnO3 photocatalyst was then fabricated by adding small amounts (0.5–2.0% wt) of PdO to mesoporous BaSnO3. After 150 min under illumination, the developed PdO/BaSnO3 photocatalyst showed complete thiophene photooxidative desulfurization and had excellent recyclability. The designed nanocomposite containing 2.0 wt% of PdO, displayed improved absorption of visible light with a bandgap reduction from 2.98 to 2.21 eV. Photoluminescence and photocurrent data of the developed photocatalysts demonstrated that the recombination of the photogenerated charge carriers was also whittled down. According to kinetic studies, the PdO content and the photocatalyst dose had a significant impact on the reaction rate which follows the pseudo-first-order model. Additionally, the mechanism of photooxidation of thiophene was discussed. This research will pave the way for the wide use of perovskite oxide photocatalysts to oxidize sulfur-containing materials under visible illumination.