Effect of TiO2 concentration on the optical properties of polymer composite PC-PS films

Abstract

The optical properties of polymer composite polycarbonate-polystyrene (PC-PS) films with different filling levels of Titanium oxide (TiO₂) were studied in the visible and ultraviolent wavelength regions. It was found that the optical absorption is due to direct allowed transitions, and the energy gaps increase from 3.4863 eV for 2.5% TiO₂ to 3.9034 eV for 7.5% TiO₂ filler content, while the width of the tail localized states decrease with increasing TiO2 content. The optical constants refractive index n, extinction coefficient k, the real
and imaginary parts of the dielectric constants have been also calculated. The dielectric constant and refractive index are also affected by TiO₂ content.