[Luminescence properties of Gd2O3:Eu3+ sol-gel thin films]

In this paper, the sol-gel method with Re2O3 (Re=Gd, Eu) as parent compounds was introduced to produce Gd2O3:Eu3+ thin films. From the luminescence intensities of the films doped with different Eu3+ concentration and annealed at different temperatures, it was found that the optimal dopant concentration and annealing procedure was 10% and 800 degrees C for 2 hours, respectively. By comparing the excitation spectra of the Gd2O3:Eu3+ film and powder, the authors found that the film has higher efficiency for energy transfer from host to dopant, which means that the film would be more suitable than the powder as a radio-luminescence material. In addition, it was first discovered that the luminescence of the film nearly disappeared after 2 hours annealing at 1000 degrees C. The phenomenon was explained with the results of SEM and XRD experiments.