Cu-InS2 Quantum dots: core-shell construction for high luminescent system

Abstract

In recent years, research has focused on the synthesis of more "green" nanoparticles where the reagents were less toxic and the products more compatible with biological cells and tissues. This is because quantum dots are increasingly used in the technological industries thanks to their properties, such as luminescence, stability in time. They are then used as drug markers, bioimaging and nanosensors. So a valid alternative to the classic quantum dots such as Pbs or Cdse, are the copper-indium sulfide (CIS) nanoparticles, which are synthesized with organic reagents but also in aqueous solution, resulting in more green and biocompatible.This project mainly has two objectives. This project mainly has two objectives. The first is the study and synthesis of copper-indium-sulfide quantum dots. In this initial phase we wanted to study the relationship between copper and indium and how this influenced the luminescence of quantum dots. It has been noted that a decrease in copper concentration causes a blue-shift in absorption spectra. Subsequently, the focus was on the synthesis of the zinc sulfide shell around the CIS, varying the concentration of zinc and studying its influence in luminescence. It has been noted that decreasing the concentration of zinc during the synthesis process had a red-shift in the spectra of luminescence, making luminescent samples that without shells were not. Last step is the study of the ligands around nanoparticles, using either a single ligand or mixing them. The characterization techniques used are the most common spectroscopic techniques such as UV-visible and the PL,PLE.