Gd2O3:Eu3+ particles prepared by glycine-nitrate combustion: Phase, concentration, annealing, and luminescence studies

Eu3+ doped Gd2O3 particles have been prepared by glycine-nitrate combustion route. Eu-O charge transfer peak shifts to higher wavelength from 260 to 273 nm with increasing Eu3+ concentration, whereas the linewidth at half maximum intensity varies with Eu3+ concentrations and annealing temperatures as well. Lifetime for D-5(0) level of Eu3+ increases with annealing temperature from 500 to 900 degrees C, and this is related to decreasing surface to volume atomic ratio of particles. Asymmetric ratio defined by the ratio of intensity of electrical dipole transition to that of magnetic dipole transition is found to be 10, which is more than the reported values (3-4) indicating enhancement in luminescence by this synthesis route.