UV-LED TiO2 photocatalytic oxidation of acetone vapor: Effect of high frequency controlled periodic illumination

We investigated the effect of controlled periodic illumination on quantum efficiency of acetone vapor photocatalytic oxidation. It was demonstrated that quantum efficiency increases with the increase of light pulses frequency and decrease of the duty cycle and at some point reaches its maximum value which is equal to the quantum efficiency obtained under the same average photon flux. Several kinetic models were applied to the experimental data. The general conclusion was made that there are only two kinetically distinguishable active species on TiO2 surface with the lifetimes in 10(-3)-10(1) s range. (C) 2014 Elsevier B.V. All rights reserved.