Facile one-pot aqueous synthesis of highly soluble and luminescent CdSe quantum dots without nitrogen bubbling

Abstract

CdSe quantum dots (QDs) have been widely used in a plethora of applications due to their relatively high photocatalytic abilities and unique properties. Herein, we report that highly water-soluble CdSe QDs were successfully prepared in open-air conditions without using an inert atmosphere. This has been accomplished through a facile one-pot method by using a novel binary mixture of thioglycolic acid (TGA) and trisodium citrate (TSC) as capping agents. Air stable and cheap sodium selenite (Na₂SeO₃) was used as the selenium precursor. By varying the reflux time, the temporal evolution of the optical, structural, and morphological properties of the as-prepared QDs were examined. The obtained QDs were characterized by XRD, HRTEM, XPS, UV-vis absorption, DRS, and PL. The results revealed that high-quality, small, spherical, and monodispersed QDs exhibiting high optical properties and superior stability in open-air conditions can be easily obtained using this facile, green approach.