Hydrothermal Synthesis And Characterization Of Cerium-Doped NaTaO₃

A series of Cerium-doped NaTaO3 photocatalysts were successfully synthesized via hydrothermal method. XRD, TEM and SEM were used to characterize the structure and morphology of the products, and the photocatalytic performance of the products was also studied by decomposing methyl orange solution under UV light.(1)Ta2O5 and NaOH were utilized as starting materials to synthesize single crystal NaTaO3 nanocube with the edge length of about 400 nm. At hydrothermal temperature 180℃, well crystalline NaTaO3 was obtained in 1h when the concentration of Ta5+ was 0.045mol/L and the concentration of NaOH was 12mol/L. Adjusting the concentration of reactant, NaTaO3 nanocube was obtained when the concentration of Ta5+ was 0.1mol/L and the concentration of NaOH was 10mol/L. The results showed that NaTaO3 can be obtained in a wide range of concentration of reactant.(2)Cerium-doped NaTaO3 powder was successfully synthesized by hydrothermal method. In the CeO2-doped hydrothermal process, concentration of reactant and hydrothermal temperature exerted a great influence on the crystal phase of the products. Adjusting the concentration of NaOH and Ta5+,hydrothermal temperature and the amount of CeO2, the CeO2-doped NaTaO3 was obtained at 180℃. NaTaO3 products showed cubic morphology with a diameter 50-150nm, and the particle size of NaTaO3 was remarkably decreased by doping of CeO2. The results showed that the optimal condition was [Ta5+]=0.045mol/L and [NaOH]=12mol/L when the hydrothermal temperature was 180℃. On the base of optimal condition, Ce3+-doped NaTaO3 was synthesized via hydrothermal method, and the products showed cubic morphology. At the same time, nanometer Na2Ta2O6/NaTaO3:Ce3+ composite was synthesized by a CTAB assisted hydrothermal method, and CTAB played an important role on the appearance of Na2Ta2O6.(3)The photocatalytic activity of the photocatalyst was evaluated by the photocatalytic degradation of methyl orange solution. The experimental results showed that the photocatalytic activity of cerium-doped NaTaO3 prepared by hydrothermal method was better than none-doped NaTaO3. Nanometer Na2Ta2O6/NaTaO3:Ce3+ composite synthesized by a CTAB assisted hydrothermal method showed good photocatalytic activity, and the Na2Ta2O6 phase played an important role in the inhancement of the catalytic efficiency.