Controllable synthesis, characterization and photoluminescence properties of morphology-tunable CdS nanomaterials generated in thermal evaporation processes

High-quality CdS nanomaterials were fabricated through thermal evaporation of a mixture of CdS and Cd powders at 650 °C and at an Ar carrier gas flow of 20 sccm (standard cubic centimeters per minute). They were in the forms of nanoparticles, nanobelts, nanowires, and nanorods (both straight and curved). The hexagonal wurtzite phase of the CdS nanomaterials was verified by XRD, and their single crystallinity confirmed by selected area electron diffraction. As revealed in field emission scanning electron microscope (FESEM) and TEM analysis, CdS nanobelts, nanowires, and nanorods can be obtained by regulating the CdS-to-Cd ratio. A mechanism for the growth of the CdS nanomaterials has been described. In the study, we investigated the optical nature of the CdS nanomaterials and observed that the CdS nanomaterials showed good photoluminescence (PL) properties. The CdS nanobelts and nanorods were similar in PL peaks whereas the CdS nanowires showed no sight of DL emission.