Room Temperature Synthesis of Doped Titania Nanoparticles using Ultrafine Grinding

A.K. Maparu, B. Rai
Tata Research Development and Design Centre, IN

Keywords: photocatalyst, titania, mechanochemical, doping

Summary:

Titania nanoparticles have attracted increased attention in the recent past due to their high photocatalytic activity, biological and chemical stability, non-toxic nature and low price. Photocatalytic nano-titania finds wide range of applications including air/water purification, deodorization, preparation of self-cleaning surfaces, anti-bacterial applications and in solar cells. Attempts have been made to dope metal and non-metal atoms on the surface of titania for improving its photocatalytic activity by decreasing the effective band gap. Among the different methods available for doping on titania matrix, mechanochemical method is most useful since the process is very simple and large scale production of doped titania is possible by this method. During mechanochemical grinding, undesired byproducts are deposited on the surface of titania, suppressing its photocatalytic activity. To remove the undesired byproducts, calcination at high temperature is generally required which is associated with particle agglomeration, sintering, phase change and increased cost of production. Herein, we report a novel wet milling method to synthesize doped titania at room temperature. The process does not require high temperature calcination resulting energy saving i.e. reduced cost of the doped photocatalyst. Under sunlight irradiation, the prepared titania photocatalysts exhibit excellent photocatalytic activity in the degradation of model pollutants in water.