Study on the Properties and Photoactivity of TiO2(nanorod)-SiO2 Synthesized by Sonication Technique

A series of TiO2 (nanorod)-SiO2nanocomposite (TS) with different mole ratios was prepared by sonication technique. Nanorod TiO2 was prepared by solvothermal assisted by EDTA, while SiO2 was prepared by sol-gel method. Various amount of SiO2 powder was combined with nanorod TiO2 to form TiO2 (nanorod)-SiO2nanocomposite. Based on XRD and TEM results, the TiO2 was rod-like anatase crystalline phase with the rod length of about 20-50 nm, while spherical SiO2 was a large particle with a diameter of about 200 nm. The deposition of nanorod TiO2 on the surface of spherical SiO2 resulted in composites with slightly smaller crystallite size than that of the pristine nanorod TiO2 of about 21-27 nm. The BET surface area of the TS composites was variable, of about 61.8–67.6 m2 g-1. The photoactivity of the composites was examined by measuring the zone inhibition of the composites to the growth of E. coli and B. subtillis, as a model of gram-negative and gram-positive bacteria, respectively. The composites have shown significant antimicrobial activity over both bacteria, which are slightly higher than that of pristine nanorod TiO2. keywords: nanorod, TiO2, SiO2, nanocomposite, sonication.