Functional Zn_xCd_1-xS nanocrystals: Synthesis and optical properties

Zinc chloride, cadmium chloride and sodium sulfide were used as raw materials to fabricate hydroxyl coated Zn_xCd_1-xS nanocrystals with 2-mercaptoethanol (ME) as the organic ligand. The nanocrystals as prepared were well dispersed in H₂O/DMF solution without any aggregation. The structure and optical properties of the these nanocrystals were studied by FTIR, UVVis, XRD, EDS and photoluminescence spectrum (PL). The digital camera was also used to directly take the photos of Zn _xCd_1-xS nanocrystals under UV-lamp. The results indicate that these nanocrystals are with good photoluminescence properties and the formation of robust bonding between ZnS nanocrystals and the organic ligand occurs in this case. It is also shown that optical materials with wavelength ranging from ultraviolet to visible light can be achieved by properly controlling Cd²⁺ doping concentration along with using 2-mercaptoethanol (ME) as the organic ligand.