Synthesis and optical properties of ZnS:Cu(II) nanoparticles

ZnS nanoparticles doped with Cu(II) were synthesized by the coordination chemistry method. Glycine was used as ligand to decrease the solubility difference of ZnS and CuS in an aqueous colloid. By this method, coprecipitation probability of CuS and ZnS is greatly enhanced. The band gap of the nanoparticles increases with Cu2+ doping concentration. Except for direct observation from the band gap obtained from the absorption spectra. A green emission band located at 490–510 nm was observed by UV excitation of the ZnS host, which indicated that Cu2+ ions substitute Zn2+ ions in the lattice and act as luminescent centers.