Sol-gel synthesis and luminescence property of ZnO:(La,Eu)Cl nanocomposite thin films

A kind of ZnO:(La, Eu)Cl nanocomposite thin film phosphor with strong red emission was synthesized by the sol-gel process. X-ray diffraction and scanning electron microscopy characterization indicate that the films were composed of nano-sized grains and a LaOCl phase appeared accompanying with (100) oriented ZnO phase after annealed at 600 oC in oxygen. The photoluminescence properties were investigated by measuring the excitation and emission spectra. These luminescence results suggested that Eu3+ ions could incorporate into the LaOCl lattice and charge transfer occurred between LaOCl phase and Eu3+ ions. La co-doping with Eu-Cl leads to the improvement of the red luminescence of Eu3+ and also suppressed the broad green emission of ZnO host