Template-free synthesis of CdS microspheres composed of nanocrystals with a new sulfur source

Cadmium sulfide (CdS) microspheres composed of CdS nanocrystals were synthesized by a one-pot solvothermal method using a new in situ S2− source and without the use of any template or capping agent. The powder X-ray diffraction measurements revealed the cubic structure of the CdS microspheres. SEM analyses indicated that the CdS microspheres are further composed with assembled CdS nanocrystals. TEM analyses revealed the crystallites size of about 15-20 nm. Optical investigation showed that the obtained CdS microspheres have an UV-vis absorption at 420 nm which is blue-shifted compared to that of bulk CdS and the calculated band gap value is 2.52 eV. Photocatalytic investigation of the CdS microspheres showed good photocatalytic activity for photodegradation of methylorange (MO) dye.