Enhancement of Luminescence Efficiency of Y(2)O(3) Nanophosphor via Core/Shell Structure

We successfully fabricated Y(2)O(3):RE(3+) (RE = Eu, Tb, and Dy) core and core–shell nanophosphors by the molten salt method and sol–gel processes with Y(2)O(3) core size of the order of 100~150 nm. The structural and morphological studies of the RE(3+)-doped Y(2)O(3) nanophosphors are analyzed by using XRD, SEM and TEM techniques, respectively. The concentration and annealing temperature dependent structural and luminescence characteristics were studied for Y(2)O(3):RE(3+) core and core–shell nanophosphors. It is observed that the XRD peaks became narrower as annealing temperature increased in the core–shell nanophosphor. This indicates that annealing at higher temperature improves the crystallinity which in turn enhances the average crystallite size. The emission intensity and quantum yield of the Eu(3+)-doped Y(2)O(3) core and core–shell nanoparticles increased significantly when annealing temperature is varied from 450 to 550 °C. No considerable variation was noticed in the case of Y(2)O(3):Tb(3+) and Y(2)O(3):Dy(3+) core and core–shell nanophosphors.