Facile and green synthesis of 1-thioglycerol capped CdSe quantum dots in aqueous solution

Abstract

CdSe quantum dots (QDs) have been synthesized in aqueous solutions of Cd(NH3)4SO4 and Na2SeSO3 in the presence of 1-thioglycerol at ambient conditions. These QDs were found to exhibit very sharp excitonic absorption peak between 400 and 430 nm and a second peak at around 360 nm and exhibit very broad fluorescence in the entire visible range with a large stokes shift. The QDs were monodisperse and stable under ambient conditions for several months. Their optical properties were found to have a strong correlation with the stoichiometric ratios of Cd:Se. 1-Thioglycerol was found to play a dual role in the synthesis of CdSe QDs, (i) catalyses the reaction to form CdSe and (ii) acts as a capping agent for these QDs. An in depth study of their electrochemical analysis have been made and a probable reaction mechanism for the formation of these QDs has been provided.