One-pot synthesis of highly luminescent and color-tunable water-soluble Mn:ZnSe/ZnS core/shell quantum dots by microwave-assisted method

In this paper, microwave-assisted method was used for rapid synthesis of highly luminescent Mn-doped ZnSe/ZnS core/shell nanocrystals in aqueous phase. A series of nanocrystals with different size was prepared in 1 h under proper condition. The as-prepared Mn-doped ZnSe/ZnS QDs exhibit the emission in the range of 565-602 nm and the highest photoluminescence quantum yield reached up to 36.3% under the optimal reaction condition. The optical properties and structure of the Mn:ZnSe/ZnS QDs have been characterized by PL spectroscopy, UV-Vis, TEM, XRD and XPS. The effects of various experimental variables, including the reaction pressure, the pH value of reaction solution, the ratio of Zn to ligand (MPA), and the post-treatment on the optical properties of the Mn:ZnSe/ZnS QDs were investigated systematically. The as-prepared MPA coated Mn-doped ZnSe/ZnS colloidal nanoparticles was utilized to ultrasensitively and selectively detect Hg2+ ions in water, the result shows that the QD-based metal ions sensor possesses high sensitivity and selectivity, and could be applied for the quantification analysis of Hg2+ ions in water.