Optical Properties of Mn-Doped ZnTe Magic Size Nanocrystals

J Phys Chem Lett. 2012 Jun 21;3(12):1663-7. doi: 10.1021/jz300300g. Epub 2012 Jun 6.

Abstract

In this letter we report successful doping of ZnTe magic size nanocrystals (MSNCs) with Mn(2+). Colloidal ZnTe MSNCs are prepared via a hot-injection method and doped with Mn(2+) via cation exchange. The doped MSNCs show an emission band centered at 620 nm with a radiative decay time of 45 μs, characteristic of Mn(2+) in ZnTe. The excitation spectrum of the Mn(2+) emission shows narrow absorption bands corresponding to different sizes of ZnTe MSNCs providing further evidence that the 620 nm emission originates from Mn(2+) incorporated in the ZnTe host, rather than Mn(2+) bound to the surface. The Mn(2+)-doped ZnTe clusters may serve as nuclei for the growth of larger ZnTe quantum dots doped with a single Mn(2+) ion.

Keywords: Mn2+; ZnTe; cation exchange; doped nanocrystals; energy transfer; luminescence.