Degradation of tetracycline hydrochloride by BaTiO3-TiO2 composite photocatalyst and its mechanism
In this paper,using butyl titanate(TBOT)and barium titanate(BaTiO3)as raw materials,BaTiO3-TiO2 composite photocatalysts were prepared by hydrothermal method.The effects of different calcination temperatures(400,500,600,700℃)on the structure,morphology,and photocatalytic performance of the composite photocatalyst for tetracycline hydrochloride(TCH)were studied.The results show that the increase in calcination temperature promotes the transformation of some TiO2 into BaTiO3,the diffraction peak of BaTiO3 increases,the grain size gradually increases,and the growth and molding of spherical particles become more complete.The band gap width of BaTiO3-TiO2 composite photocatalyst is 3.03 eV,and the change in calcination temperature does not change the absorption band edge of BaTiO3-TiO2.The absorption intensity of the composite photocatalyst first increases and then decreases with the increase in calcination temperature.The BaTiO3-TiO2 composite absorption intensity after annealing at 600℃is the highest.At 180 min,the degradation efficiency of the BaTiO3-TiO2 photocatalyst annealed at 600℃for TCH can reach a maximum of 92.80％,which is 24.08％higher than that of the catalyst annealed at 400℃.The gradual attenuation of the degradation rate of TCH after five repetitions is less than 7％.The degradation rate of TCH during the fifth repetitions is 70.11％,and the degradation rate of BaTiO3-TiO2 is 93.19％at pH=6.2 for 180 min.
BaTiO3-TiO2photocatalysistetracycline hydrochloridehydrothermal methodcalcination temperature
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