Optical studies of Cd2+ and Mn2+ Co-doped ZnS nanocrystals

We report the structural and optical properties of co-doped ZnS nanocrystals synthesized by chemical co-precipitation method using Methacrylic Acid (MAA) as a capping agent. XRD patterns confirm the zinc blend structure of the samples. As calculated by the Debye-Scherrer formula and TEM image, the mean nanocluster diameter of the sample is ranging between 4-8 nm. EDAX analysis of co-doped sample confirms the presence of Mn2+ and Cd2+ ions in addition to the sulfur deficiencies. Optical characterizations of both doped and co-doped samples are carried out by UV-vis and Photoluminescence (PL) spectroscopy. We observed the coexistence of two metal ions and their effect on the luminescence properties (i.e. red emission) of the host material. The mechanism of energy transfer for the emissions are tried to discuss.