Solid-state synthesis of Bi_2O_3/BaTiO_3 heterostructure: preparation and photocatalytic degradation of methyl orange

摘要

In this work, Bi_2O_3/BaTiO_3 heterostructure were prepared through a solid milling and annealing process. It was found that Bi~(3+) dissolved in the BaTiO_3 lattice and the chemical bond was constructed between the interface of Bi_2O_3 and BaTiO_3 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_2O_3/BaTiO_3 heterostructure. Furthermore, UV-indu-ced catalytic activities of the Bi_2O_3/BaTiO_3 heterostructure was studied by a degradation reaction of methyl orange (MO) dye. The band gap of the Bi_2O_3/BaTiO_3 heterostructure was estimated to be 3.0 eV. Compared with pure Bi_2O_3/BaTiO_3 powders, the Bi_2O_3/BaTiO_3 heterostructure had a much higher catalytic activity. An excellent performance of the photocatalytic property of the Bi_2O_3/BaTiO_3 heterostructure is ascribed to high mobility of species and effective separation of photogenerated carriers driven by the photoin-duced potential difference generated at the Bi_2O_3/BaTiO_3 junction interface, demonstrating that the Bi_2O_3/BaTiO_3 heterostructure is a promising candidate as a photocatalyst.