Synthesis and Characterizations of Undoped and Mn Doped CuS Nanoparticles

Undoped and manganese (Mn) doped CuS nanoparticles were synthesized at ambient temperature by wet chemical route. The doping of Mn ions in CuS nanoparticles was confirmed by the energy dispersive analysis of X-rays (EDAX). The X-ray diffraction (XRD) showed, both the nanoparticles possesses hexagonal structure. The scanning electron microscopy (SEM) revealed that the undoped CuS naoparticles were uniformly distributed having spherical shape, while Mn doped CuS nanoparticles showed flake like morphology. The transmission electron microscopy (TEM) images showed that the particles size vary from 17 to 20 nm in case of undoped CuS, while the particles size increased in case of Mn doped CuS and varied from 23 to 37 nm. The optical absorption spectra showed direct bandgap values of 1.6 and 1.7 eV for undoped and Mn doped CuS nanopartides, respectively. The photoluminescence (PL) spectra for four excitation wavelengths viz 250, 300, 350 and 400 nm showed that the emission intensity increases in case of Mn doped CuS nanoparticles compared to undoped CuS nanoparticles for all the four excited wavelengths. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) showed that Mn doped CuS naoparticles were more stable than undoped CuS nanoparticles. The obtained results are deliberated in details.