Synthesis of high-quality CdSe quantum dots in aqueous solution

By employing sodium selenite as selenium source and mercaptosuccinic acid (MSA) as stabiliser, the authors demonstrate that high-quality CdSe quantum dots (QDs) can be conveniently prepared in aqueous solution. The obtained products were characterised by UV-vis absorption, photoluminescence spectra, X-ray powder diffraction (XRD), and transmission electron microscopy (TEM). XRD analysis showed that the MSA-capped CdSe QDs were of cubic zinc-blende crystal structure, UV-vis absorption spectra and TEM exhibited that the QDs were nearly monodisperse and relatively uniform. The quantum yield of as-prepared CdSe QDs can reach up to 18%, and the full-width at halfmaximum value was merely 35 nm.