Transition Metal Modified Zinc Oxide for Spintronics

Abstract

In the present study, an attempt has been made to synthesize pure and 3d-transition metal doped (up to 5%) ZnO using chemical route (Co-precipitation method) in the basic medium. Synthesized samples were characterized using XRD, FTIR, UV-Visible Spectrophotometer, SEM and SQUID in order to understand structural, chemical, optical, morphological and magnetic behaviour of these samples. XRD analysis gives information about the successful doping up to 5%, as no impurity peak has been seen in any case and all the samples exhibit wurtzite hexagonal structure with average particle size 7 -26 nm. FTIR spectra reveal the formation of Zn-O bond as we observed the reflection at 452.798 cm-1in all synthesized pure and doped systems. Optical studies inferring that the addition of Ni, Co and Mn decreased the optical band-gap. SEM images do not give any significant information, as the clumps of spherical particles have been observed in these synthesized samples. Magnetic measurements indicate that Ni doped samples exhibit both diamagnetic and ferromagnetic character, later being more dominant. However, Co and Mn doped system exhibit only ferromagnetic behaviour. Such ferromagnetic behaviour is new to the field with Ni and Mn (5%) doping.