Binapani Goswami, Ranjit Singha
In the present work the synthesis of undoped and Mn- doped ZnO nanoparticles by simple coprecipitation method is reported. The nanoparticles were characterized by transmission electron microscopy (TEM), Xray diffraction (XRD), UV-Vis spectroscopy and Photoluminescence (PL) spectroscopy for their structural and optical properties. X-ray diffraction data revealed the formation of hexagonal wurtzite phase for both undoped and Mn-doped nanoparticles. The mean crystallite size as obtained by Debye-Scherrer formula for undoped and doped ZnO nanoparticles of different concentrations are 26.64 nm, 21.66 nm, 23.60 nm and 22.31 nm respectively. The broadening in the XRD patterns clearly indicates the presence of very small nanocrystals. A linear decrease in the band gap is observed with increase of doping percentage. The room temperature PL spectra reveal that all the particles have a high purity with perfect crystallinity; however some crystal defects (vacancy, interstitial etc) are also present.