Magnetism of core-shell Ti:TiO nanoparticles

Authors

Xiaohui Wei
Ralph Skomski, University of Nebraska-LincolnFollow
Balamurugan Balasubramanian, University of Nebraska-LincolnFollow
David J. Sellmyer, University of Nebraska-LincolnFollow

Date of this Version

2010

Comments

Published in JOURNAL OF APPLIED PHYSICS 107, 09B516 (2010). Copyright © 2010 American Institute of Physics. Used by permission.

Abstract

Ti nanoparticles were produced using a cluster-deposition method. Ti:TiO core-shell structures were fabricated by partially oxidizing the surface of the Ti nanoparticles produced by a cluster-deposition system via multistep annealing at 250 °C in oxygen. X-ray diffraction and transmission-electron microscopy studies reveal an increase in the thickness of the TiO shell with increasing annealing time. The magnetic moment and the coercivity of the core-shell nanoparticles increase with the TiO shell thickness, which is consistent with homogenous bulk defects in TiO. The core-shell nanoparticles display an abnormal hysteresis loop, which probably reflects a combination of antiferromagnetic exchange and magnetocrystalline anisotropy.