Self-rising synthesis and luminescent properties of Eu³⁺-doped nanoceria

Rare earth Eu³⁺-doped nanoceria powders were prepared by polyvinyl alcohol assisted self-rising synthesis. The X-ray diffraction and Raman spectra data indicate the formation of solid solutions and the existence of oxygen vacancies after Eu³⁺ doping into the samples. The powders are well-dispersed and the particle size is around 100 nm, as can be seen from the scanning electron microscopy. Under the excitation of ultra-violet light 373 nm, the nanoceria powders emit weak orange-red light at low Eu³⁺ doping concentration. However, excited at the same condition, the nanoceria samples generate strong red light at high Eu³⁺ concentration. The luminescence difference is due to the obvious change of the predominant transition emission. Additionally, the luminescence intensity of the Eu ³⁺-doped nanoceria powders is dramatically enhanced as compared with the same composition samples achieved through simple solution combustion synthesis. The phenomena are beneficial for their potential applications in opto-electronic devices.