The Effects of Electron Beam Irradiation on Structural and Optical Properties of TiO₂ Particles

Abstract

The effect of electron irradiation on structural and optical properties of TiO2 particles has been studied. The crystallinity change was observed at low dose irradiation (4-20 kGy) while phase transformation from pure anatase to mixture of anatase-rutile was inevitable after 100 kGy without significant change in crystallinity. The highest fraction of rutile:anatase ratio was 20:80 obtained at 700 kGy. Morphology study demonstrated that TiO2 particles were spherical, nano-sized and heavily agglomerated with no obvious microstructural changes were observed after irradiation. The direct and indirect band gap (Eg) showed a decrement at low dose but re-increased after irradiation at >100 kGy. The highest Eg was at 700 kGy which can be explained by the changes of TiO2 atomic structure in the presence of mixture anatase:rutile. Therefore, the electron beam irradiation does affect both structural and optical properties of TiO2 nanoparticles. This is expected to affect the photocatalytic activity of TiO2.