http://www.e-journals.in Chemical Science Transactions DOI:10.7598/cst2015.1027 2015, 4(2), 570-576 Sol-Gel Synthesis of Nanoparticles of N, S-Codoped Titanium Dioxide and its Use for Photocatalytic Degradation of Trypan Blue AJAY SINGH SISODIYA 1 , DIPTI SONI 1 , RAKSHIT AMETA 1 and K. L. AMETA *,2 1 Department of Chemistry, PAHER University, Udaipur – 313003 (Raj), India 2 Department of Chemistry, Mody University of Science and Technology, Lakshmangarh - 332311 (Raj), India klameta77@hotmail.com Received 9 February 2015 / Accepted 13 February 2015 Abstract: In recent years, heterogeneous photocatalysis has gained wide attention in water purification as one of the important advanced oxidation processes (AOPs) due to its effectiveness in degrading and mineralizing the organic compounds. N, S-codoped TiO 2 has been prepared by sol- gel method with thiourea as dopant source. The rate of photocatalytic degradation of dye was monitored spectrophotometrically. The effect of variation of different parameters like pH, concentration trypan blue, amount of photocatalyst, dopant percentage and light intensity on the rate of photocatalytic degradation of dye was observed. A tentative mechanism for the photocatalytic degradation of trypan blue has also been proposed. Keywords: Photocatalytic degradation, N, S-codoped titanium dioxide, Trypan blue Introduction Contamination of water and air due to organic matter poses severe threat to life on the earth 1 . Dyes are widely used in many industries such as textile, leather tanning, food industry etc. It was reported that the amount of current world’s dyestuffs production is about 10 million Kg per year and between 1 to 2 million kg of active dyes have entered the biosphere, either in dissolved or suspended form in water 2 . Advanced oxidation process (AOP) is emerging as a promising technology, which has been successfully used to decompose many hazardous chemical compounds to acceptable levels, without producing sludge, which requires further handling 3 . There are various methods for removal of organic and inorganic compounds from the wastewater as filtration, electrolysis, precipitation, ion exchange and adsorption process 4 . Most of these methods require high capital and recurring expenditure and consequently, they are not suitable for small scale industries 5 . Among all these methods, photocatalysis is highly effective and low cost process than the other methods. TiO 2 is an important photocatlayst, because it is more efficient and shows RESEARCH ARTICLE