Solar light-activated photocatalytic degradation of gas phase diethylsulfide on WO3-modified TiO2 nanotubes

Artificial solar light responsive high surface area WO3-modified TiO2 nanotubes have been efficiently used for performing the gas phase photocatalytic degradation of diethylsulfide, taken as simulant for the live yperite Chemical Warfare blister Agent, known as mustard gas. They were prepared by impregnating hydrothermally-synthesized titanate nanotubes with tungstate salt prior to the final calcination step. The influence of the WO3 content, the inlet diethylsulfide concentration and the relative humidity on the photocatalytic activity as a function of time on stream has been investigated in terms of DES removal efficiency and of deactivation behavior. Modification of TiO2 nanotubes with 4 wt.% of WO3 enhanced the photocatalytic activity in terms of DES removal efficiency and of resistance to sulfate deactivation. Correlation between the surface species and the on-stream activity and behavior of the photocatalysts was proposed, as well as possible reaction mechanism pathways. (C) 2013 Elsevier B.V. All rights reserved.