Preparation of YAG : Europium red phosphors by spray pyrolysis using a filter-expansion aerosol generator

Europium-doped yttrium aluminum garnet (YAG) phosphor particles were prepar ed from mixed nitrate solutions by the FEAG (filter expansion aerosol gener ator) process. The crystallinity, morphology, and luminescence of the YAG:E u particles were investigated. The prepared particles had an amorphous phas e, which turned into phase-pure YAG particles after annealing above 1000 de grees C. A cubic-structure YAG phase was formed by the reaction of crystall ine Y2O3 and the aluminum component. The prepared particles had spherical m orphology. The mean size of the YAG:Eu particles increased from 0.45 to 1.0 mu m when the overall solution concentrations were increased from 0.02 to 1.2 mol/L. The optimum doping concentration of europium for the maximum bri ghtness of phosphor particles was 1.3 at.%. The cathodoluminescence (CL) in tensity was strongly affected by the annealing temperatures. The maximum CL value of the particles was 55 cd/m(2).