Glycolthermal synthesis and characterization of hexagonal CdS round microparticles in flower-like clusters

Hexagonal CdS round microparticles in flower-like clusters were synthesized by glycolthermal reactions of CdCl2 and thiourea as cadmium and sulphur sources in 1,2-propylene glycol (PG) at 100–200 °C for 10–30 h. Phase and morphology were detected using X-ray diffraction (XRD), and scanning and transmission electron microscopy (SEM, TEM). The products were pure phase of hexagonal wurtzite CdS. The quantitative elemental analysis of Cd:S ratio was detected using energy dispersive X-ray (EDX) analyzer. Raman spectrometer revealed the presence of fundamental and overtone modes at 296 and 595 cm−1, corresponding to the strong 1LO and weak 2LO modes, respectively. Photonic properties were investigated using UV–visible and photoluminescence (PL) spectroscopy. They showed the same absorption at 493–498 nm, and emission at 431 nm due to the excitonic recombination process. A possible formation mechanism was also proposed, according to experimental results.

► CdS as one of II–VI semiconducting materials. ► Lab-made Teflon-lined stainless steel autoclaves enable us to form hexagonal CdS. ► By 100–200 °C processing, round microparticles in flower clusters were synthesized. ► A promising material for multiple potential applications.