Akurati, K: "Synthesis of TiO2 based nanoparticles

Various gas phase synthesis routes have been employed to produce TiO2 based nanoparticles for photocatalytic applications. Synthesis routes have been selected depending up on the feasibility/constraints of the particular process to produce a given kind of material.The first attempt at producing the photocatalysts involved the synthesis of pure TiO2 nanoparticles by a flame aerosol process. The growth behaviour of TiO2 particles which has significant influence on their crystallinity and surface area, has been controlled by varying the process parameters and selecting suitable flame configurations. An existing method to determine the crystallinity of the powder has been modified which facilitates comparison f the degree of crystallinity of the nanoparticles synthesized by various methods. Resultant TiO2 nanoparticles were characterized by X-ray diffraction (XRD) and nitrogen physisorptio to determine the degree of crystallinity quantitatively and surface area, respectively, and the decomposition rate of an industrial dye, methylene blue, has been taken as the measure of the photocatalytic activity (PCA). The importance of an optimum combination of crystallinity andsurface area for improved PCA has been shown by comparing the PCA of the as-synthesized nanoparticles with commercial TiO2 (Degussa P25)