Synthesis and characterization of Bi2Ti2O7/TiO2 heterojunction by glycerol-assisted alcoholthermal method

The heterostructured Bi2Ti2O7/ TiO2 composites with different shapes were synthesized by a simple glycerol-assisted alcoholthermal method. The as-prepared Bi2Ti2O7/ TiO2 composites were characterized by UV-vis, XRD, FESEM, TEM, BET, TG/DTA, EDS and photoluminescence (PL) spectroscopy. The effects of addition amount of glycerol on the structure and properties of products were investigated. The photocatalytic activities of the as-prepared samples were evaluated through photocatalytic decolorization of methylene blue aqueous solution. The results showed that structure and morphology of Bi2Ti2O7/TiO2 heterojunction can be readily controlled by adjusting the volume ratio of glycerol and ethanol. When volume ratio of glycerol and ethanol was 0, 0.05 and 0.10, the morphology of Bi2Ti2O7/ TiO2 heterojunction was granular, rugby and petal shaped, respectively. In comparison with that of commercial grade nano-titanium oxide (referred to as P25), the Bi2Ti2O7/ TiO2 heterojunction had enhanced photocatalytic efficiency irradiated under simulated sunlight. Petals shaped Bi2Ti2O7/TiO2 heterojunction had higher photocatalytic activities because it possessed higher specific surface areas and larger pore volume.