Facile Synthesis and Characterization of MPA Capped CdSe and CdSe/ZnS Nanocrystals

Nanosized metal chalcogenides have aroused great interest in the scientific community owing to their important non linear optical properties, luminescent properties, quantum size effects and other important physical and chemical properties. CdSe is one such material which shows strong fluorescence, that can be tuned by simply varying the size of the particle for use in various applications such as biological fluorescence labeling, solar cells, light emiting devices etc. In this work, we report the successful synthesis of 3mercaptopropionic acid (MPA) capped CdSe and CdSe/ZnS nanocrystals through a simple, safe, non toxic, cost effective and easily reproducible chemical synthesis followed by hydrothermal treatment. X-ray diffraction (XRD), UV-Visible spectroscopy (UV-Vis), Photoluminescence spectroscopy (PL), Fourier transform infrared spectroscopy (FT-IR) and High resolution transmission electron microscopy (HR-TEM) were used to study the structural, morphological and optical properties of the as-synthesized CdSe and CdSe/ZnS nanocrystals. From the obtained results, it was found that the synthesized CdSe and CdSe/ZnS nanocrystals exhibited zinc blende phase with good nanocrystallinity and the size of the particles were found to be around 8 nm for CdSe and around 6 nm for CdSe/CdS nanoparticles.