Enhanced Dy3+ white emission via energy transfer in spherical (Lu,Gd)3Al5O12 garnet phosphors

Abstract

AbstractThe Dy3+ doped (Lu,Gd)3Al5O12 garnet phosphors with spherical morphology were obtained via homogeneous precipitation method, followed by calcination at 1100 °C. The particle morphology does not change significantly, but can be controlled by adjusting the urea content. The synthesis, structure, luminescent properties of precursor and resultant particles were analyzed by the combined technologies of XRD, FE-SEM, PLE/PL decay behavior. The (Lu0.975Dy0.025)AG phosphors display strong blue and yellow emission at ~481 nm (4F9/2 → 6H15/2 transition of Dy3+) and ~582 nm 4F9/2 → 6H13/2 transition of Dy3+), respectively. The phosphors have similar color coordinate and temperature of (~0.33, ~0.34), ~5517 K, respectively, which are closed to the white emission. The particle size and luminescent intensity decreased while the lifetime increased with the urea concentration increasing. The Gd3+ addition does not alter the shape/position of emission peaks, but enhance the blue and yellow emission of Dy3+ owing to the efficient Gd3+ → Dy3+ energy transfer. The [(Lu1-xGdx)0.975Dy0.025]3Al5O12 phosphors are expected to be widely used in the lighting and display areas.