Fabrication and optical properties of Mn2+‐doped CdS/ZnS core/shell nanocrystals

We have fabricated Mn2+-doped CdS/ZnS core/shell nanocrystals (NCs) where Mn ions exist within ZnS shell layer, and have studied optical properties of the samples with different Mn concentrations. The exciton and Mn PL are clearly observed in the Mn2+-doped CdS/ZnS core/shell NCs. The intensity of the exciton PL decreases with the Mn concentration, while that of the Mn PL increases. Furthermore, the Stokes shift of the exciton PL is suppressed by doping of the Mn ions. Our findings reveal that the Mn ions within the ZnS shell is excited by energy transfer from excitons of the CdS cores. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)