Synthesis and upconversion luminescence of monodispersed, submicron-sized Er3+:Y2O3 spherical phosphors

Abstract: Spherical monodispersed, submicron-sized Er3+:Y2O3 powders were prepared via a homogeneous precipitation method using nitrates and urea as raw materials. The structure, phase evolution and morphology of Er3+:Y2O3 precursor and the calcined powders were studied by means of XRD, TG/DTA, FTIR and SEM methods. The upconversion spectra of spherical monodispersed Er3+:Y2O3 powders were excited with 980nm laser diode (LD) and measured by a spectrofluorometer. The results showed that monodispersed spherical powders with a particle size of 200–210nm were obtained after the precipitates were calcined at 800°C for 2h. The solution concentration of Er3+ and Y3+ had a significant impact on the morphologies of the precursor and powders. Low solution concentration such as 0.015M can promote precipitation precursor to keep uniform spherical shape. The resultant monodispersed Er3+:Y2O3 phosphors exhibit upconversion luminescence properties and the intensity of the upconversion luminescence reaches the maximum when the Er3+ concentration is 3at.%. [Copyright &y& Elsevier]