In this brief, a comprehensive review of the UV/visible-TiO2 photocatalytic oxidation process is presented with an insight into the mechanisms involved, the role of titanium dioxide as a catalyst, irradiation sources, types of reactors, and a comparison between various modes of TiO2 application. An overview of the development and enhancement of the activity of TiO2 nanoparticles in photocatalysis is presented. The topics covered include a detailed look at the unique properties of the TiO2 nanoparticles and their relationship to photocatalytic properties. The utilization of the TiO2 nanoparticles as photocatalysts, in the non-doped and doped forms is also reviewed. Finally, the use of modified TiO2 nanoparticles has made a significant contribution in providing definitive mechanistic information regarding the visible light photocatalytic processes.

Autorentext
Mohamed A. Barakat is a Professor of Environmental sciences at the Faculty of Meteorology, Environment, King Abdulaziz University, Saudi Arabia. and a Professor of Environmental sciences and Mineral Technology in the Central Metallurgical R& D Institute (CMRDI), Cairo, Egypt.
Prof. Barakat has been awarded the following prizes, Prize of excellence in Articles Citation, KAU, Saudi Arabia, 2011, Prize of excellence in Scientific Publications, KAU, Saudi Arabia, 2010, King Hassan II Prize for Environment, Morocco, 2008, National Award of the Environment , Academy of Science, Egypt, 2003, Listed in Who's Who in Science and Engineering, 2003.
Additionally, Prof. Barakat has published 61 articles in ISI Journals, 8 reports of research project, and 50 presentations in International Conferences. He has been awarded the following fellowships, DAAD Postdoctoral Fellowship, University of Wuppertal, Germany, 2008, Postdoc, Department of Materials Sc.., University of Delaware, USA, 2003- 2004. ,and Visiting Scholar, Department of Civil & Environmental Eng., University of Delaware, USA, 2001.

Inhalt
Introduction.- Fundamentals and mechanism of TiO2 photocatalysis.- Photocatalysis enhancement routes.-ApplicationsWastewater treatment.- Visible light photocatalysis.- Conclusions