Growth of photoluminescent cadmium sulphide quantum dots from soluble single source precursors in solution and in film

Photoluminescent cadmium sulphide (CdS) quantum dots (QDs) were successfully obtained by a single-source route via a non-injection one-pot approach using octadecene (ODE) as a non-coordinating solvent and myristic acid (MA) as capping agent. The synthetic scheme makes use of two metal-organic molecules belonging to the xanthate family, cadmium diethyl-xanthate (CdDEX) and cadmium dibutyl-xanthate (CdDBX) single-source precursors. The thermal conversion of both xanthates was explored in the temperature range of 150 °C-180 °C. Following this heat treatment material made from both precursors showed photoluminescence from the direct band gap having a PLQY from 5% (CdDEX) to 13% (CdDBX). The nucleation and growth of CdS nanoparticles in thin solid films was studied by transmission electron microscopy. The surface topography and morphology of the thin films was observed by atomic force microscopy.