PRESENTATION BY
Professor George Kiriakidis
Institute of Electronic Structure and Laser / Foundation for Research and Technology University of Crete

PRESENTATION TITLE
Metal Oxide vis Light Active Photocatalytic Materials

ABSTRACT
Indoor air quality plays an important role on human health. Nitric oxides (NO and NO2) and volatile organic compounds, VOCs (such as formaldehyde, benzene) are typical inorganic and organic indoor air pollutants. They normally originate from cooking, combustion, tobacco smoke, furniture and building materials. They may also be associated with traffic pollutants and can cause serious health problems like drowsiness, headache, sore throat and mind fatigue. The US Environmental Protection Agency points out that indoor air pollution is a much greater risk to human health than outdoor air pollution particularly in big cities where the average person spends more than 90% of time indoors. So, it is of vital importance to remove these pollutants in order to improve the indoor air quality for people’s health. The most promising and effective method for air purification is Photocatalysis, a method considered as the most advanced oxidation process to resolve environmental problems. Metal oxide semiconductors such as TiO2 and ZnO are commonly used as photocatalysts. TiO2 photocatalyst in particular has been extensively studied for air depollution due to its low cost, innoxiousness, chemical inertness and high photocatalytic efficiency under UV light. However, the UV light is only 0.001–0.05 W/m2 in indoor illumination systems. To extend TiO2 as a photocatalyst to visible light region, it is necessary to dope TiO2 with metals and nonmetals. This presentation will report on the synthesis and characterization of TiO2 materials doped with transition metals in different concentrations capable to absorb and activate under visible light irradiation. The material is Manganese (Mn) doped TiO2 powder prepared by a modified sol gel method. The novelty of the reported material is that it acts as an effective pollutant reducing agent, is harmless to humans and suitable for indoor applications. The crystal structure, particle size, morphology, and porosity along with surface morphology and elemental analysis of the materials are presented and photocatalytic efficiencies will be discussed both for material in powder form and as additives in a number of building material matrices.

ABOUT THE PRESENTER
Professor Kiriakidis got his BSc in Physics from the Aristotelion University of Thessaloniki, Masters from UMIST, UK and PhD from Salford University, UK. Since 1981, he is a faculty member of the Physics Department of the University of Crete initially as a Lecturer and Assistant Professor and currently as an Associate Professor. From 1985 to 1992 he was the Deputy Director of the Microelectronics Research Group at FORTH and from 1992 he established and leads the Photonic and Electronic Materials Lab and the Transparent Conductive Materials Group. The current research interests of his group focus on the growth and study of Metal Oxide wide Band gap materials (TCOs) for Flexible Transparent Electronics, ultra sensitive Gas Sensing devices, Transparent Thin Film Transistors (TTFTs) and Electrochromic/Photocatalitic structures. He has published his work in more than 100 scientific papers in refereed journals, over 110 national and international conferences (including 27 invited) and is the co-author in 7 scientific reports and two proceedings books. He is also the Chairman for the Bi-annual International Symposium on TCOs (TCO series) established in 2006.

REFRESHMENTS WILL BE PROVIDED AT 14h45

For further information, please contact:
Professor Khalil Arshak, Tel. No: (061) 202267 or Email: khalil.arshak@ul.ie