Optical and kinetic studies of CdS:Cu nanoparticles

CdS:Cu nanoparticles were successfully synthesized by a coprecipitation method using mercaptoethanol as a capping agent. Thermoluminescence (TL) spectra of CdS:Cu nanoparticles were studied for different exposure time. The synthesized products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV–Vis spectrometry. XRD and SEM measurements showed that the size of the crystallites was in the range 8–17 nm. Optical measurements indicated a blue-shift in the absorption band edge upon Cu doping. The direct allowed bandgap of undoped and Cu-doped CdS nanoparticles was 2.53 and 2.64 eV, respectively. We also calculated the kinetic parameters for Cu-doped CdS nanoparticles from the TL glow curves measured at 254, 249, and 244 °C with variation of the ultra-violet (UV) exposure time. The glow curve shows general order kinetics, and its kinetic parameters are calculated.