Structure and luminescence of annealed nanoparticles of ZnS : Mn

Structural and light-emitting properties of nanoparticles of ZnS:Mn anneale d in vacuum at temperatures up to 525 degrees C are presented. Annealing th e 3.5 nm particles at temperatures up to 350 degrees C caused growth of som e particles without substantial change in the luminescence or ZnS lattice. After annealing at 400-525 degrees C, the high-temperature wurtzite phase o f ZnS appeared, accompanied by an increase of the average particle diameter to approximately 100 nm and a rearrangement of the Mn ions. Dramatic incre ase in cathodoluminescence emission was also observed and is compared to th e structural information obtained from electron microscopy, x-ray diffracti on, x-ray absorption fine structure, and electron paramagnetic resonance me asurements. (C) 2000 American Institute of Physics. [S0021-8979(00)06421-5] .