| Project Detail |
Colloidal nanocrystals (NCs) that absorb and emit in the near-infrared (NIR) region are of paramount importance in the field of optoelectronics (LEDs, LASERs, solar cells, telecommunication) and biological imaging. However, most of the NIR emitting NCs are based on heavy metals (Pb, Cd, Hg) which are highly toxic and are restricted from widespread use by the European regularity concerns. Therefore, the development of NIR emitting environmentally friendly (Cd/Pb/Hg- free) NCs are of interest. NIRLUMIN proposes a strategy to develop high NIR (1-1.35um) luminescent, stable AInTe2/(Ga/In)2S3/Zn(S/Se) core/shell/shell (CSS) NC heterostructures with controlled bandgap and size in which the outer shells will protect the surface of the core and enhance the photoluminescence quantum yield by passivating the dangling bonds and surface traps while the intermediate layer will stop diffusion to prevent the undesirable bandgap enhancement. Further, the advantages of these NCs will be directly translated into device performance in the LED. For biological imaging, these nanostructures will be over-coated with a ceramic-type alumina shell and transferred to the aqueous phase. The whole work will be conducted in five major steps. (i) Synthesis of CSS NCs, characterization and study of their structural and photophysical properties (ii) Surface functionalization to investigate the surface ligand chemistry on their optical and electrical properties and to make the NCs compatible for devices and bio-application (iii) Cytotoxicity study and bio-imaging using the Alumina coated NCs. (iv) Optoelectronic characterization, to understand the optical and electronic characteristics of the NCs on film. Finally (v) fabrication of LED using these NCs as an active layer and optimization to achieve an efficient NIR emission. |
