Enhanced photocatalytic decomposition of gaseous ozone in cold storage environments using a TiO2/ACF film

In order to promote the efficient photocatalytic (PC) degradation of gaseous ozone in cold storage environments using activated carbon felt-supported titanium dioxide (TiO2/ACF), two strategies were implemented in this study at a temperature of 3 ± 1 °C and relative humidity 90 ± 3%. The two strategies are as follows (i) ACF-supported TiO2 treated with γ-ray irradiation, and (ii) ACF-supported silver-doped TiO2 containing Ag nanoparticles prepared by reduction using γ-radiolysis. The rate constant (k′) of the apparent pseudo first-order kinetic model was used to define the degradation efficiency of gaseous ozone in the PC process. The results showed that (1) from analysis of the X-ray photoelectron spectrum, optimum changes had occurred in the crystal structure of the TiO2 that had been γ-ray-irradiated with a total dose of 20 KGy (TiO2*-20), resulting in an increase of 12.6% in the k′ of TiO2*-20/ACF compared with that of TiO2/ACF, (2) the presence of Ag nanoparticles prepared by reduction using γ-radiolysis on the TiO2/ACF film enhanced the photocatalytic degradation of gaseous ozone with a molar ratio of Ag/Ti below 1%. The k′ of the films is highly dependent on the Ag/Ti molar ratios. With a Ag/Ti molar ratio of 1%, a maximum of k′ value can be attained for the Ag + (TiO2*-20)/ACF film under the experimental conditions.