Applied Science and Convergence Technology 2015; 24(4): 96-101
Published online July 31, 2015
Copyright © The Korean Vacuum Society.
Byungwook Jeon and Yu Kwon Kim*
Department of Chemistry and Department of Energy Systems Research, Ajou University, Suwon 443-749, Korea
Correspondence to:Yu Kwon Kim
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Quantitative evaluation of photocatalytic activity of oxide nanoparticles in aqueous solution is quite challenging in that the kinetic reaction rate is determined by a complicated interplay among various limiting factors such as light scattering and absorption, diffusion and adsorption of reactants in condensed liquid phase, photoexcited charge separation and recombination rate, and the exact nature of active sites determined by detailed morphology and crystallinity of nanocrystals. Here, we present our simple experimental results showing that the kinetic regime of a typical photocatalytic degradation experiment over UV-irradiated TiO2 nanoparticles in aqueous solution is in that dominated by the photoactivity of TiO2 and its concentration. This result lays a firm ground of using the measured kinetic reaction rate in evaluating photocatalytic efficiency of oxide nanocrystals under evaluation.
Keywords: Photocatalysis, TiO2 nanocrystals, Reaction rate, Photodegradation, Methylene blue