Effect of rare earth oxide nanoparticles on the photoluminescence and conductivity properties of PVA films

Nanoparticles of Gd₂O₃ and Sm₂O₃ were prepared by solution combustion method. Nanocomposite films of PVA-Gd₂O₃ and PVA-Sm₂O₃ were prepared by solution casting method. These were characterized by XRD to give the nanocrystallite size as 19nm and 30nm respectively and to confirm the formation of a composite while TEM gave nano-particle size as 26nm and 37nm respectively. Both nanocomposites showed good photoluminescence. Impedance measurements showed that the conductivity decreased in the nanocomposites compared to PVA and that Correlated Barrier Hopping was the probable mechanism for conduction in both nanocomposite films. The fitting of the electric modulus to KWW equation indicated a non-Debye type of relaxation in both these films. The relaxation time decreased with increasing temperature in both nanocomposites.