"Nanotechnology and nanomaterials"

Investigations on the photocatalytic activity of sulfur doped TiO2
Kucio K.1, Charmas B.1, Zięzio M.1
1 Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University. Maria Curie-Sklodowska Sq. 3, 20-031 Lublin, Poland. 
E-mail: karolina.kucio@poczta.umcs.lublin.pl

The intensive development of industry caused a rapid increase in environmental pollution. Water pollution due, among others, to the presence of dyes originating from industry is a mass problem facing humans worldwide. One of the effective methods of wastewater treatment is heterogeneous photocatalysis which belongs to Advanced Oxidation Processes. For photocatalytic degradation of dyes the semiconductors are often applied. The most commonly used photocatalyst is titanium dioxide. It is characterized by low cost, non-toxicity, chemical stability and long durability. TiO2 has a wide band gap (3.2 eV for anatase and 3.0 for rutile) and therefore exhibits a large photocatalytic activity at the UV radiation. 
The light emitted by the Sun contains mainly radiation in the infrared (~52%) and visible ranges (Vis ~43%) and only ~5% is UV radiation. Therefore, for the effective exploitation of the solar energy, it is necessary to obtain a photocatalyst with a large activity at the visible light. Doping TiO2 with small amounts of "foreign" chemical elements is the most frequently used  method to obtain a titanium catalyst active in the visible light. 
The aim of the paper was to obtain  sulfur doped TiO2 photocatalysts that are active in the visible light area.The structural properties of photocatalysts were investigated using the nitrogen adsorption/desorption method. The photocatalytic properties of the obtained materials were tested as regards Safranin T at visible light (Vis). In addition, the effect of calcination at 400°C on the properties of obtained materials was discussed.

1.	Kumar S.G., Devi L.G. Review on modified TiO2 photocatalysis under UV/visible light: selected results and related mechanisms on interfacial charge carrier transfer dynamics //  Journal of Physical Chemistry A.-2011.-115(46).-P.13211-13241