Photocatalytic degradation of methylene blue using novel flower-like zirconium bismuth molybdate thin film, grown by temperature-assisted CBD method

摘要

Thin films of a novel metal molybdate are successfully coated on soda lime glass by one step chemical bath deposition method. The deposition is carried out under different bath temperature ranging from 30 to 70 °C. In order to analyze the crystalline structure, X-ray diffraction study is carried out. Film thickness and morphology are examined through atomic force microscope and scanning electron microscope. Optical studies are done by UV-Vis-NIR absorbance spectra and photoluminescence spectra. All the samples have absorbance in the UV-Vis region and possess direct allowed transition with bandgap values ranging from 2.17 to 2.83 eV. Direct current show good ohmic response and possess resistivity in the range characteristic of wide bandgap materials. The material possesses three major photoluminescence emission peaks in the green and blue wavelength regions. Thin film grown at 50 °C showed increased absorbance width, minimum bandgap energy, larger electron-hole separation efficiency and more porous flower-like morphology which indicates its higher photocatalytic ability. The photocatalytic degradation process for the removal of methylene blue from waste water, under sunlight irradiation using thin film grown at 50 °C as photocatalyst has been discussed in detail.