Synthesis, Magnetic Anisotropy and Optical Properties of Preferred Oriented Zinc Ferrite Nanowire Arrays
1 Key Lab for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, 730000, Lanzhou, People’s Republic of China
2 Department of Physics, Xinxiang University, 453003, Xinxiang, People’s Republic of China
Nanoscale Research Letters 2010, 5:1289-1294 doi:10.1007/s11671-010-9640-zPublished: 22 May 2010
Preferred oriented ZnFe2O4 nanowire arrays with an average diameter of 16 nm were fabricated by post-annealing of ZnFe2 nanowires within anodic aluminum oxide templates in atmosphere. Selected area electron diffraction and X-ray diffraction exhibit that the nanowires are in cubic spinel-type structure with a  preferred crystallite orientation. Magnetic measurement indicates that the as-prepared ZnFe2O4 nanowire arrays reveal uniaxial magnetic anisotropy, and the easy magnetization direction is parallel to the axis of nanowire. The optical properties show the ZnFe2O4 nanowire arrays give out 370–520 nm blue-violet light, and their UV absorption edge is around 700 nm. The estimated values of direct and indirect band gaps for the nanowires are 2.23 and 1.73 eV, respectively.