Gd2Ti2O7:Ce Particles’ Apparent Activation Energy and Luminescence Properties

Abstract:

Gd2Ti2O7:Ce nanoparticles were prepared by co-precipitation method of different initial solution concentrations; The phase composition, particle morphology and luminescence properties of the samples were characterized by XRD, TG-DTA and SEM. Powders’ thermal analysis kinetics and activation energy in the synthesis process were also calculated at different heating rates. It is shown that there are three stages in the process of the precursor's phase transformations during heating, initial solution concentrations are 0.08mol/L and 0.04mol/L respectively. The average apparent activation energies of the precursors’ three reaction stages are 42.43、145.58、381.98 kJ?mol-1 and 51.28、161.51、446.30kJ?mol-1 using the Doyle-Ozawa and Kissinger methods separately. Meanwhile, the grain growth activation energies of two different concentrations are 12.58 kJ?mol-1 and 19.54 kJ?mol-1 severally. It is concluded that Gd2Ti2O7:Ce nanoparticles with higher surface activity have the best luminescence property when calcined at 1173K for 2h, especially the samples doped 0.7 mol% Ce is optimal at the concentration of 0.08mol/L.