Cationic substitution sites in Mn2+-doped ZnS nanoparticles

摘要

Mn2+-doped ZnS nanoparticles of average size 2.5 +/- 0.3 nm have been studied and characterized in the dopant concentration range 0.1-0.3 using XRD, EPR, XPS and photoluminescence methods. The experimental results obtained from these studies indicate that the doping of Mn2+ occurs primarily at the T (d) sites at low dopant concentration, causing the T-4(1)(G) -> (6)A(1)(S) transition to take place in the host lattice; the observed decrease in the intensity of photoluminescence at high dopant concentration is due to the setting in of the strong Mn2+-Mn2+ interaction arising from cluster formation at the highly distorted sites near the particle surface.