SYNTHESIS AND STRUCTURE OF PURE AND Mn-DOPED ZINC OXIDE NANOPOWDERS.

Zn_1-xMn_xO (x = 0, 0.02, 0.06, 0.10, 0.15) nanopowders were synthesized by the sol-gel technique calcinated at low temperatures. By decreasing the grain size in ZnO, the solubility of magnetic impurity has been increased and no detectable secondary phases were observed even in the high Mn-doping samples. The phase formation, size and morphology of nanoparticles were investigated using X-ray diffraction and SEM observations. The samples were ferromagnetic and the Curie point was found in the range 150-170 K for Zn_0.94Mn_0.06O and 135-150 K for Zn_0.98Mn_0.02O. Optical characterization and the effect of doping were carried out by means of Fourier transform infrared (FTIR) spectroscopy. Kramers-Kronig analysis was employed to evaluate the optical constants of pure ZnO and ZnO:Mn nanopowders. [ABSTRACT FROM AUTHOR]