Quantum efficiency of the ⁵D₀ level of Eu³⁺ at C₂ site in cubic nanocrystalline Y₂O₃

In the present the authors are trying to work out how the quantum efficiency depends on the nanocrystalline size. Cubic nanocrystalline Y₂O₃:Eu³⁺ samples were prepared by chemical self-combustion. The bulk Y₂O₃:Eu³⁺ was obtained by annealing the nanocrystalline at 1 000 °C for 2 h. The emission spectra, XRD and fluorescence decay showed that the emission intensities are increased and fluorescence decay becomes slow with an increase in particle diameter of the samples. Two routes were used to estimate the quantum efficiency of the ⁵D₀ level of Eu³⁺ at C₂ site. The quantum efficiencies of ⁵D₀ level of Eu³⁺ at C₂ site in the samples depend on the nanocrystalline sizes. Finally, a detailed discussion about these two approaches for estimating the quantum efficiencies was made.