Facile synthesis of CdSe QDs in aqueous solution of TGA capping agent

Abstract EN

Colloidal cadmium selenide quantum dots (CdSe QDs) nanoparticles capped by different amounts of a short chain thiol ligand thioglycolic acid (TGA), were prepared in aqueous medium under nitrogen bubbling at different temperatures using cadmium chloride as the cadmium source, and sodium selenite as the selenium source.

Transmission electron microscope (TEM) analysis of the prepared sample reveals the size and crystalline nature of the particles.

Electron diffraction spectroscopy (EDS) analysis indicates the presence of respective elements in the resultant powdered sample with nonstoichiometric state.

CdSe quantum dots have been prepared with different amounts of TGA.

FTIR analysis confirms the attachment between thiol group of TGA and CdSe QDs.

Absorption and photoluminescence analysis indicates the red shift towards longer wavelength by increasing the amount of TGA where the bandgap decreases from 2.8 to 1.5 eV and the particle size increases from 1.7 nm to 3.2 nm.