Optical absorption of sol-gel derived ZnO/TiO2 nanocomposite films

ZnO/TiO2 nanocomposite films on quartz substrates were prepared by the sol- gel method, and the corresponding optical absorption properties were invest igated. In the ultraviolet region, it was found that the position of fundam ental absorption edge partially depends on the composition of the ZnO/TiO2 films, and shifts toward a shorter wavelength with the increasing content o f ZnO in the films. Moreover, a blueshift of the absorption edge resulted f rom a quantum size effect and the quantum confinement effect was observed i n the ZnO/TiO2 system.