![]() The resultant solution was stirred for 24 h and kept for 1 day aging. The metal oxide gel was produced by increasing the pH by dropwise addition of 1 N NH 3 solution. The solution of titanium (IV) isopropoxide Ti(OC 3H 7) 4 was added dropwise in isopropyl alcohol and stirred for 30 min. The present work aims at studying the structural, optical and electrical conductivity of TiO 2/SiO 2 nanocomposites in comparison with synthesized pure TiO 2 and SiO 2 nanoparticles. The TiO 2, SiO 2 nanoparticles were synthesized by sol–gel method using titanium isopropoxide and tetra methyl orthosilicate as starting material. In this work, TiO 2, SiO 2 nanoparticles and TiO 2/SiO 2 nanocomposites were prepared by a novel and simple route. The surface area has further more increased by forming composite with SiO 2. Commercially, TiO 2 is available with surface area of around 60 m 2/g. The efficiency of TiO 2 for dye-sensitized solar cells (DSSC) is highly depending on particle size and surface area. The photo catalytic efficiency of Titania (TiO 2) depends highly on particle size and surface area of the material (Hakki et al. Although the sol–gel method is considered as a suitable method to synthesize ultra-fine particles, this method needs a large quantity of solution, longer processing time and heat treatment for crystallization since amorphous TiO 2 has a very little photocatalytic activity. Nanosized TiO 2 has been fabricated using sol–gel, sputtering, combustion flame, and thermal plasma (Zhang and Xu 2004 San Vicente et al. The mesoporous nano TiO 2/SiO 2 composite is a promising area due to optimum porous size. The use of large surface area semiconductor for materials in dye-sensitized solar cells (DSSC) is necessary to provide sufficient light absorption and charge separation which are the two critical stages in the solar–electric energy conversion. With regards to nanocrystalline TiO 2, the optical properties have been tentatively studied in recent years and some interesting results obtained. In particular, nanosized TiO 2 has many advantages in the dye-sensitized solar cells. Nano crystalline TiO 2 has attracted continuous attention due to its versatile applications in optical devices, sensors, catalysis and photocatalysis etc. This is due to the size of these particles. Nanoclusters of metals and semiconductors are more and more considered as building blocks of future technology. The field-dependent photoconductivity of TiO 2/SiO 2 nanocomposite shows nearly 300 folds more than that of TiO 2 nanoparticle for a field of 800 V/cm. It also confirms the absence of macropores and the presence of micro and mesopores. ![]() The BET surface area for TiO 2/SiO 2 nanocomposite is found to be 303 m 2/g and pore size distribution has average pore diameter about 10 nm. The crystallite size of the as-synthesized samples was calculated by Scherrer’s formula. The UV–Vis spectrum of as-synthesized samples shows similar absorption in the visible range. The synthesized samples are characterized by X-ray diffraction, UV–Vis spectroscopy, Fourier transform infrared spectroscopy, Brunauett–Emmett–Teller and field-dependent photoconductivity. Mesoporous TiO 2, SiO 2 nanoparticles and TiO 2/SiO 2 nanocomposites were successfully synthesized by sol–gel method using titanium (IV) isopropoxide, tetra-ethylorthosilicate as starting materials. Mesoporous materials have been of great interest as catalysts because of their unique textural and structural properties. The use of titania–silica in photocatalytic process has been proposed as an alternative to the conventional TiO 2 catalysts. ![]()
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