TiO2/SiO2 Nanostructured Photocatalyst for degradation of Organic Contaminants

Abstract

This is a comparative study between different nanostructured (TiO2/SiO2) photocatalytic composite material, m-TiO2 and commercial TiO2 anatase powder. Photocatalytic materials were synthesized by using sol-gel processing method. Morphology and structure crystallinity were characterized by using several techniques including: X-ray diffraction technique (XRD), Raman spectra, Fourier transformer infra-red spectroscopy (FTIR), PL Spectra, Scanning electron microscopy analysis (SEM), Ultraviolet-visible absorption spectroscopy (UV-Vis spectroscopy), and Energy dispersive spectroscopy (EDAX). Photocatalytic degradation efficiency of different prepared photocatalysts were studied by applying all the photocatalysts in degradation of intense organic MB solution under UV light source. Resulted that, 45% (TiO2/SiO2) nanostructured composite was the most efficient composite material as compare to the other percentages. In comparative study of photocatalytic reaction of 45% (TiO2/SiO2) nanostructured composite, mesoporous-TiO2 and commercial-TiO2, resulted as mesoporous-TiO2 was found most efficient photocatalytic material with high no of active sides for reaction for degradation of industrial intense MB dye solution and can easily regenerated as compared to the commercial TiO2. Several photocatalytic reaction experiments were also performed for studied, the effect of numerous reaction parameters such as photocatalyst load (0.02, 0.03, 0.04 g/100ml), pH variation (acidic, neutral, basic), organic dye concentration in aqueous solution (10ppm, 20ppm, 30ppm, 40ppm, 50ppm), reaction irradiation time and effect of catalyst regeneration on photocatalytic efficiency of m-TiO2 photocatalytic material for efficient degradation of MB solution in environmentally friendly products i.e. water and carbon dioxide. For m-TiO2 photocatalyst, the degradation efficiency towards wastewater containing organic dyes displays the highest value under acidic pH value 3.50, degradation of 50ppm MB solution just achieved with in 50 min. This is due to the reason that m-TiO2 provide a xvii variety of active sides for UV light absorption and charge separation. This study also exhibits that photocatalytic degradation efficiency of m-TiO2 towards organic contaminants have direct relation with catalyst dosing, dye solution concentration and with irradiation reaction time. This photocatalytic comparative study provides a highly efficient approach for degradation of textile effluent (containing