Synthesis and Photoluminescence of Nanocrystalline ZnS:Mn^(2+)

摘要

The influence of the synthesis conditions on the properties of nanocrystalline ZnS:Mn2+ is discussed. Different Mn2+ precursors and differentudratios of the precursor concentrations [S2-]/[Zn2+] were used. The type of Mn2+ precursor does not have an effect on the luminescenceudproperties in the synthesis method described. On going from an excess of [Zn2+] to an excess of [S2-] during the synthesis, the particleuddiameter increases from 3.7 to 5.1 nm, which is reflected by a change in the luminescence properties. Photoluminescence measurements alsoudshowed the absence of the ZnS defect luminescence around 450 nm when an excess [S2-] is used during the synthesis. This effect isudexplained by the filling of sulfur vacancies. The ZnS luminescence is quenched with an activation energy of 62 meV, which is assigned to theuddetrapping of a bound hole from such a vacancy.