Synthesis and Surface Passivation of CuInS2/MnS/ZnS Core–Multishell Nanocrystals, Their Optical, Structural, and Morphological Characterization, and Their Bioimaging Applications

This article describes the design and characterization of CuInS2-based core–multishell nanocrystals with the appropriate architecture of MnS as the inner layer and ZnS as the outer layer. These are wider bandgap materials being used to develop the type-I core/shell structure. The designed CuInS2/MnS/ZnS colloidal nanocrystals were synthesized by a multistep hot-injection method. This material gains importance in view of its superior luminescence property. The existence of an efficient dual emission in both green and NIR regions, with high stability corresponding to 543 and 752 nm, highlights its utility as an efficient bioimaging probe, and its formation was confirmed with combined optical and structural characterization techniques. The photoluminscence study revealed that the optimum concentration of both shells was 0.1 mmol (by varying shell concentration from 0.1 to 0.5 mmol), since beyond this concentration the intensity of the shells was reduced gradually according to the concentration. The zinc blen...