Size and quality control of fast grown CdS quantum dots

Abstract

The synthesis of high quality II‐VI semiconductor quantum dots (QDs) is fundamental for developing new devices in several applications such as biomarkers, solar cells or blue‐UV lasers. These emerging technologies are funded on the size‐dependent optical properties of the QDs. Consequently, it is a crucial aspect to get insight into different ways for syntheses of their nanosized particles. In this work, we use two different QD elaboration methods: (i) a single source precursor thermal growth methodology and (ii) a microwave synthetic route. Using both protocols, high quality small QDs (Ø < 5 nm) are produced. Both growing techniques offer the advantage to be simple and fast: 2 hours (i) and less than 25 minutes (ii) in duration, growth temperatures do not exceed 280 °C. For both elaboration procedures, we report a unique physics/chemistry cross‐disciplinary study on these small size QDs: mass spectrometry (MS) technique provides background data about composition, size and stability of particles; crystalline structure and size distribution of the QDs are obtained from X‐ray diffraction (XRD) and transmission electron microscopy (TEM); room temperature (RT) optical spectrometry of nanodispersions – photoluminescence (PL) and absorption – reveals quantum size effects. (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)