Structure effects on the optical properties of thin (PbLa)TiO3 films

amorphous thin films of pb1-xlaxtio3 (with x=0, 13 and 27 mol %) were prepared by the polymeric precursor method and deposited by spin coating on glass substrates. the films were characterized by x-ray diffraction (xdr) and scanning electron microscopy (sem) and the band gap energy of the amorphous plt films was calculated from the uv-vis spectra. the obtained values were compared to that theoretically calculated. the observed decrease of the band gap was attributed to increased density of defects in the amorphous structure. futhermore photoluminescence (pl) at room temperature was observed for thin (pbla)tio3 films.