OICC Press International Nano Letters 2228-5326 3 1 (December 2013) 2013 01 22 Synthesis and characterization of ZnO-TiO2 nanocomposites and their application as photocatalysts 10.1186/2228-5326-3-5 EN Md Ahsan Habib Department of Chemistry, Faculty of Science, University of Dhaka, Dhaka, 1000, BD Md Tusan Shahadat Department of Chemistry, Faculty of Science, University of Dhaka, Dhaka, 1000, BD Newaz Mohammed Bahadur Department of Applied Chemistry and Chemical Engineering, Noakhali Science and Technology University, Noakhali, BD Iqbal M I Ismail The Center of Excellence in Environmental Studies, Department of Chemistry, Faculty of Science, King Abdulaziz University, Jeddah, 21589, SA Abu Jafar Mahmood Department of Chemistry, Faculty of Science, University of Dhaka, Dhaka, 1000, BD Journal Article 2013 01 22 Abstract Nanocomposite ZnO-TiO 2 powders of varying ZnO/TiO 2 molar ratios have been prepared from their salt/compound by heating at 600°C and 900°C and characterized using scanning electron microscope and X-ray diffraction techniques. The nanosized powders can decolorize/degrade brilliant golden yellow (BGY), an azo dye extensively used in textile industries, in water under solar irradiation. The effects of various parameters such as photocatalyst loading, molar ratio of ZnO/TiO 2 , pH of the solution, initial dye concentration, and irradiation time on the photodecolorization have been investigated. ZnO-TiO 2 nanocomposite (6 g/L) in the molar ratio of 1:1 or 3:1, prepared at 900°C, can efficiently decolorize about 98% of 20 mg/L BGY at pH of about 7 by 2-h illumination in sunlight. The initial dye decolorization follows pseudo-first-order kinetics. Finally, trial experiments were done using real textile wastewater to find out the effectiveness of the photocatalysts to a more complex system.