Hydrothermal synthesis of barium germanate microrods and photocatalytic degradation performance for methyl blue

Abstract Barium germanate microrods were prepared by a facile hydrothermal process without any surfactants. X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and photoluminescence spectra were used to characterize the structure, morphology, size and optical properties of the barium germanate microrods. XRD and SEM observations show that the microrods with hexagonal BaGe 4 O 9 phase have the diameter of 500 nm to 1.5 μm. The size of the barium germanate microrods can be tuned by controlling the hydrothermal temperature, reaction time and surfactants. The influence factors including the irradiation time, content of the barium germanate microrods and MB concentration on the photocatalytic degradation of methylene blue (MB) have been analyzed. The barium germanate microrods show a MB degradation ratio of 83.49% after the irradiation time for 30 min using 1.25 mg/ml barium germanate microrods in 10 mgL −1 MB solution.