Mn-doped ZnO nanoparticles: Preparation, characterization, and calculation of electronic and magnetic properties

In this work, Zn1-xMnxO nanoparticles were prepared by PEG sol-gel method. Structure and morphologies of Zn1-xMnxO nanoparticles were investigated by using transmission electron microscope. Magnetic properties were measured by using a vibrating sample magnetometer (VSM). In calculation, electronic structure and magnetic properties for pure ZnO and Zn1-xMnxO have been investigated by means of the first principle calculations based on local density approximation (LDA) and LDA+U scheme, packaged in the ABINIT code. The calculation was performed using self-consistent projected augmented plane wave (PAW). The zinc oxide was modeled using 2 x 2 x 2 super-cell (totally containing 32 atoms) in ideal hexagonal wurtzite structure. A 9 x 9 x 5 Monkhorst-Pack k-point mesh was used for the super cell calculation and a plane wave cutoff energy of 16 Hartree was used to assure convergent results. The results indicate that ZnO has energy band-gap about 1.97 eV which is underestimated when compared to experiments. The magnetic dipole moments of the Zn1-xMnxO when the manganese contents (x) are 0.0000, 0.0625, 0.1250 and 0.1875 equal 0.00 mu(b), 3.83 mu(b), 7.78 mu(b) and 10.37 mu(b), respectively. The doped manganese atoms seem to play an important role for the appearance of ferromagnetism. (c) 2013 Elsevier B.V. All rights reserved.