Synthesis And Properties Of Aurivillius Bismuth-based Photocatalytic Materials

Energy crisis and environmental pollution have been restricting the development of human society on major issues. Photocatalysis technology turns out to be an ideal solution for the energy crisis and environmental pollution because of its economic and green benefits. Aurivillius bismuth-based photocatalytic materials have high light quantum efficiency due to their Aurivillius structure and unusual electronic properties owing to Bi element, which make them potential application in photocatalytic system. In the present study, a series of Aurivillius structure bismuth-based compounds have been fabricated by simple hydrothermal and solvothermal methods. The main contents are as follows:(1) Hierarchical porous BiF3-Bi2NbO5 F core-shell structures have been successfully prepared via a simple solvothermal route. A possible growth mechanism for the core-shell structure was proposed based on time-dependent-evolution experiments. X-ray powder diffraction was used to determine the phase composition. Scanning electron microscopy and transmission electron microscopy were employed to characterize the morphologies of the as-prepared samples. Experiments demonstrated that the volume ratio of ethylene glycol to water played a determinative role in the final morphology of the products. The band gap of the as-preparedBi F3-Bi2NbO5 F composite was estimated to about 3.47 eV. The novel hierarchical BiF3-Bi2NbO5 F core-hell structures could serve as a catalyst for photosensitized degradation of Rhodamine B under visible light irradiation. Moreover, the photodegradation efficiency of the samples was greatly associated with their surface morphology.(2) Hierarchical porous Bi2TiO4F2 hollow spheres have been successfully prepared via a simple solvothermal route. X-ray powder diffraction was used to determine the phase. Scanning electron microscopy was employed to characterize the morphologies of the as-prepared samples. Experiments demonstrated that the volume ratio of ethylene glycol to water played a determinative role in the final morphology of the products. The band gap of the as-prepared Bi2 Ti O4F2 was estimated to about 3.5 eV. The novel hierarchical Bi2TiO4F2 hollow spheres could serve as a catalyst for photosensitized degradation of Rhodamine B under visible light irradiation. Moreover, the photodegradation efficiency of the samples was greatly associated with their surface morphology.(3) Bi2O2CO3 nanosheets with the size of about 500 nm and 1 μm have been successfully prepared via a simple hydrothermal method. The effect of surfactant on the size of the product was studied through comparative experiments. X-ray powder diffraction was used to determine the phase. Scanning electron microscopy was employed to characterize the morphologies of the as-prepared samples. The band gap of the as-prepared Bi2O2CO3 was estimated to about 3.22 eV. Bi2O2CO3 nanosheets served as a catalyst for photosensitized degradation of Rhodamine B under visible light irradiation and the size of nanosheets palyed an important role for the photodegradation efficiency.