Materials Chemistry and Physics, Vol.112, No.3, 789-792, 2008
Synthesis and optical properties of CdS/ZnS coreshell nanoparticles
Synthesis and optical properties of manganese (Mn2+)-doped, polyvinyl pyrrolidone (PVP)-capped cadmium sulphide (CdS) nanoparticles coated with zinc sulphide (ZnS) are reported. Colloidal solution of Mn2+-doped CdS nanoparticles capped with PVP is synthesized using methanol as solvent. PVP is used to control the particle size and to prevent agglomeration. Mn2+ doping is expected to help in increasing the CdS band edge photoluminescence (PL) emission. Addition of zinc nitrate and sodium sulphide alternately to the Mn2+-doped, PVP-stabilized CdS colloid led to the formation of ZnS-coated CdS coreshell nanoparticles. Photoluminescence emission spectra recorded for(CdS-PVP)Mn nanoparticles showed two emission peaks, one at 416 nm and the other weaker peak at 586 nm which is attributed to Mn2+ emission. Intensity of Mn2+ peak increased with increase in the Mn2+ content. Mn2+ emission disappears when ZnS is coated over the CdS core, resulting in pure CdS band edge emission. (C) 2008 Elsevier B.V. All rights reserved.