Investigation of Microstructure and Photocatalytic Performance of a Modified Zeolite Supported Nanocrystal TiO2 Composite

A modified zeolite/TiO2 composite (MZTC) was prepared through a method of saturated infiltration and synthesis in situ. The crystalline phase, micromorphology, elementary composition, specific surface area, pore size distribution, chemical bond and band gap variation of the products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), BET specific surface area and pore size distribution analysis (BET), Fourier transform infrared spectroscopy (FTIR) and UV-vis diffuse reflectance spectroscopy (UV-vis DRS), respectively. The microscopic characterization results showed that TiO2 was homogeneously dispersed in the structure of zeolite at the nanoscale range, and a strong chemical bond was established between TiO2 and zeolite. The photocatalytic performance of MZTC was evaluated by studying the degradation rate of methylene blue (MB) dye in aqueous solution under UV-light irradiation. The results of the degradation experiment showed that the MB degradation rate of MZTC-2.5 was the highest, reaching 93.6%, which was 2.4 times higher than hydrolysis TiO2 powder (HTOP) containing the same mass of pure TiO2. The MB degradation rate of MZTC-2.5 still maintained 86.5% after five tests, suggesting the excellent recyclability of MZTC-2.5. The possible mechanism of MB degradation was also discussed.