Photoacoustic study of optical and thermal properties of alloyed CdTexS1−x nanocrystals

Photoacoustic (PA) technique has been applied to study the optical and thermal properties of the alloyed CdTexS1−x (nanocrystals (NCs) with different (Te/(S+Te)) molar ratio (x=0, 0.2, 0.4, 0.6, 0.8 and 1). Increasing x value causes clearly observed red shift of the corresponding exciton peak in PA spectra. The same spectra were compared to those obtained by a regular UV–Vis. absorption. The effective mass approximation (EMA) model was applied to determine the size of the NCs. The calculated sizes of the alloyed NCs are in a good agreement with the directly measured values obtained using high resolution transmission electron microscopy (HRTEM). The values of thermal diffusivity and thermal conductivity obtained using PA technique show at least an order of magnitude larger than that of the bulk values.