Optical and magnetic properties of Zn0.98Mn0.02O nanoparticles

Abstract

Pure and Mn-doped colloidal ZnO particles were prepared in a solvo-thermal via sol–gel process by base-catalyzed hydrolysis of zinc acetate. We have studied the structural, magnetic and optical properties of the samples using X-ray diffraction (XRD), transmission electron microscopy, energy dispersive X-ray analysis, superconducting quantum interferometer device and UV–Vis spectroscopy. The XRD spectra show that all the samples are hexagonal wurtzite structures. The calculated average particle size of the samples was approximately 7–3 nm, indicating that the particle size decreased by doping with manganese. Magnetic investigations showed that at room temperature the Mn-doped ZnO possessed ferromagnetism with the saturation magnetic moment of 0.194 emu/g. The room temperature PL measurements illustrate UV-emission centered at 351 nm (3.53 eV), which is ascribed to the near-band-edge emissions of ZnO, violet emission at 512 nm (2.42 eV). The UV–Vis spectra showed a blue-shift from 3.42 to 3.78 eV when the ZnO doped with manganese.