Visible light-activated palladium oxide-decorated barium titanate nanocrystals for efficient photocatalytic oxidative desulfurization of thiophene

Abstract

Herein, nanostructured barium titanate (BaTiO₃, BTO) decorated by palladium oxide (PdO) traces (0.5∼2.0 wt. %) were merely constructed to be active under visible light irradiation with a high surface area (130−144 m²g⁻¹). The produced PdO/BTO nanocomposites exhibited significant activity under visible light through their wide absorption edge (up to 503 nm) and bandgap narrowing (down to 2.46 eV). The photocatalytic desulfurization of thiophene (THP), as an emerging sulfur-containing compound, is performed over the produced PdO/BTO with extensively upgraded efficiency compared to pure BTO or PdO alone. The photocatalytic performance of 2.0 gL⁻¹ dose of 1.5 % PdO/BTO showed complete desulfurization of 600 ppm sulfur-containing THP within 120 min at a reaction rate constant of 0.0378 min⁻¹. In addition, the spent photocatalyst exhibits a sustainable use for five independent cycles with a distinct efficiency of 94 %. This effective photocatalytic activity is related to the visible light capability as well as the efficient separation of photogenerated charge carriers due to the presence of PdO traces. The proposed desulfurization route of THP is also highlighted.