Solid-state synthesis of Bi₂O₃/BaTiO₃ heterostructure: Preparation and photocatalytic degradation of methyl orange

In this work, Bi₂O₃/BaTiO₃ heterostructure were prepared through a solid milling and annealing process. It was found that Bi³⁺ dissolved in the BaTiO₃ lattice and the chemical bond was constructed between the interface of Bi₂O₃ and BaTiO₃ after annealing process. Powder X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and UV-visible absorption spectra were used to characterize the Bi ₂O₃/BaTiO₃ heterostructure. Furthermore, UV-induced catalytic activities of the Bi₂O₃/BaTiO ₃ heterostructure was studied by a degradation reaction of methyl orange (MO) dye. The band gap of the Bi₂O₃/BaTiO ₃ heterostructure was estimated to be 3.0 eV. Compared with pure Bi₂O₃ powders, the Bi₂O₃/BaTiO ₃ heterostructure had a much higher catalytic activity. An excellent performance of the photocatalytic property of the Bi₂O ₃/BaTiO₃ heterostructure is ascribed to high mobility of species and effective separation of photogenerated carriers driven by the photoinduced potential difference generated at the Bi₂O ₃/BaTiO₃ junction interface, demonstrating that the Bi₂O₃/BaTiO₃ heterostructure is a promising candidate as a photocatalyst.