Industrial pollution is the major source of global air, water and soil pollution and refers to all pollution which can directly or indirectly, be linked with industry. Due to the extensive use of dyes in industries, it has become an integral part of industrial effluent. The potential toxicity of dyes and their visibility in surface water, removal or degradation of dyes has been a matter of considerable interest. Conventional purification methods are inefficient. Hence, semiconductor assisted photocatalysis has been widely employed to treat the effluent. The present investigation has been focused on the modification of titania by metal or non-metal ions, to extend the light responsible range from UV region to visible region, and further enhanced by the formation of nanocomposites with vanadia. The work described in this book is aimed at the synthesis and characterization of Titania and modified Titania (Ag, N or S doped Titania) nanocatalysts by sol-gel method, and Vanadia/Titania nanocomposites by wet impregnation method. The work also describes the synthesis and characterization of nanoporous materials and its application on effluent treatment.