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

摘要

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 Hg_(2+)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 Hg_(2+)ions in water.