Effect of Cr content on the properties of magnetic field processed Cr-doped ZnO-diluted magnetic semiconductors

Abstract

Cr-doped ZnO-diluted magnetic semiconductor (DMS) nanocrystals with various Cr contents were synthesized by hydrothermal method under high magnetic field. The result indicated that both the amount of Cr contents and high magnetic field significantly influenced crystal structure, morphology, and magnetic property of Cr-doped ZnO DMSs. When the Cr contents increased from 1at to 5at, the morphology of grains sequentially changed from flower-like to rod-like and then to the flake-like form. All the samples remained hexagonal wurtzite structure after Cr ions were doped into the ZnO crystal lattice. The Cr doping led to the increasing amount of defects and even enhanced the magnetic property of the matrix materials. All the Cr-doped ZnO DMSs obtained under high magnetic field exhibited obvious ferromagnetic behavior at room temperature. The results have also shown the successful substitution of the Cr 3+ ions for the Zn 2+ ions in the crystal lattice. Copyright © 2012 Shiwei Wang et al.