The study of the applicability of ionizing radiation to increase the photocatalytic activity of TiO2 thin films

Abstract

The paper presents the results of studying the efficiency of using ionizing radiation to modify the surface morphology and structural properties of TiO2 thin films, and the effect of ion modification on the photocatalytic activity of Rhodamine B. decomposition. Structural and morphological changes in thin films were characterized by irradiation with doses of 1014–1016 ion/cm2 using scanning electron microscopy, atomic force microscopy, energy-dispersive analysis and X-ray diffraction. Modification by ion irradiation of thin films leads to a change in grains orientation, a decrease in their size, and an increase in the active surface area. Formation of grains preferred orientation at high radiation doses is caused both by grains rotation as a result of distorting and deformation factors caused by radiation, and by grains partial fragmentation. It was shown that in the case of modified samples of thin films, not only an increase in the rate decomposition reaction constant by 2–4.5 times compared with the initial samples, but also the degree of mineralization is observed. According to the data obtained, the maximum value of mineralization as a result of photocatalytic reactions for initial films was no more than 75–76%. While for irradiated samples, this value varies from 83 to 90% depending on the irradiation dose. For modified films, an increase in crack resistance and resistance to degradation to prolonged tests of photocatalytic activity is observed.