Photoluminescence properties and energy transfer in Y₂O₃：Eu³⁺ nanophosphors

The photoluminescence (PL) properties of Y₂O₃:Eu³⁺ nanophosphors were systematically investigated with the goal of improving the color quality and quantum efficiency of Y₂O₃:Eu³⁺ nanophosphors for potential applications in nano-scale devices. The emission spectra, excitation spectra and fluorescence decay curves were employed to trace the energy transfer process from Eu³⁺ at C_3i site to Eu³⁺ at C₂ site. The experimental results show that the energy transfer process becomes more and more efficient with the increase in the Eu³⁺ concentration. The emission of Eu³⁺ at C₂ site is favorable as it has high radiative efficiency and better color quality. The successful suppress of the emission Eu³⁺ at C_3i is especially important for its applications in general illumination or display technology. The quantum efficiency and color quality of Y₂O₃:Eu³⁺ can be improved by controlling the energy transfer between the Eu³⁺ at S₆ site and Eu³⁺ at C₂ site.