Anatase TiO2 and Levyne type microporous silico alumino phosphate SAPO-35 are synthesized by using hydrothermal method. TiO2/SAPO-35 nanocomposites were prepared by sol-gel method with different weight ratios. The synthesized materials were characterized by various analytical techniques such as PXRD, SEM/EDAX, TG/DTA, BET-Surface area, FT-IR, UV-Vis, XPS, MAS-NMR and photocatalytic study. From PXRD results it clearly evidenced that, the TiO2 anatase peaks and SAPO-35 combined peaks are in the composite. The spherical shaped TiO2 nanoparticles were found to be dispersed over the rhombohedral SAPO-35 particles, which was analysed by SEM. BET-surface area analysis revealed that, the calcined SAPO-35 has the surface area of 448 m(2)/g, was decreased to 222 m(2)/g for composite which is due to the presence of TiO2 particles having surface area of 85 m(2)/g on the surface of SAPO-35. The oxidation state and co-ordination of various elements present in nanocomposite was composed by X-ray photoelectron spectroscopy. MAS-NMR analysis has shown that SAPO-35 has tetrahedral Al, P and Si oxides. Eventhough Al is unique Si and P are in two different environment namely one in S6R and another in D6R with double intensity. The photocatalytic performance of methylene blue degradation under sunlight radiation by the synthesized TiO2/SAPO-35 was analyzed. The TiO2/SAPO-35 composites degrade the methylene blue under sunlight irradiation in 25 minutes against 90 minuts for pure TiO2 anatase. A plausible mechanism on photocatalytic activity is also proposed.

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