Current Applied Physics, Vol.14, No.5, 749-756, 2014
Anionic polymerization in Co and Fe doped ZnO: Nanorods, magnetism and photoactivity
The growth mechanism of Zn1-xCoxO (ZC) and Zn1-xFexO (ZF) nanorods, and resulting magnetic and optical properties have been studied. The ZC and ZF nanorods were prepared by sol-gel synthesis route. X-ray diffraction results in polycrystalline phase with wurtzite structure of ZC and ZF nanorods. The transmission electron microscopy images show the formation of nanorods. The growth mechanism of nanorods is explained on the basis of agglomeration of Zn2+ with OH- ions which is react with poly vinyl alcohol involve anionic polymerization of oriented growth. Magnetic measurement of ZC and ZF nanorods exhibit superferromagnetic behavior and the large value of saturation magnetization observed at room temperature. The magnetization below room temperature measurement confirms the origin of observed magnetism. Raman and photoluminescence spectra show good photoactivity. The observed Raman active modes show wurtzite structure belongs to C-6v symmetry group. Photoluminescence measurements of ZC and ZF nanorods exhibit ultraviolet peaks at 413.90 nm (similar to 3 eV) due to free exciton emission and at 546.31 nm (similar to 2.27 eV) due to transition from deep donor states which arises from oxygen vacancy. (C) 2014 Elsevier B.V. All rights reserved.
Keywords:DMS nanostructures;Sol-gel growth;Electron microscopy (TEM);Magnetic properties;Photoluminescence;Raman Spectra