Interparticle Interaction Effects in the Magnetic Properities NiO Nanorods

Published

May 1, 2005

Author(s)

M Seehra, H Shim, P Dutta, A Manivannan, John E. Bonevich

Abstract

Magnetic properties of sol-gel synthesized 5 nm nanorods of NiO, with and without oleic acid coating to affect interparticle interactions, are reported. Particle morphologies were studied by transmission electron microscopy and temperature variations (5 K to 300 K) of the magnetization and electron magnetic resonance (EMR) spectra at 9.28 GHz were measured to determine the respective blocking temperatures Tb(m) and Tb(emr). For these particles with magnetic moment/particle 1200 B, following differences are noted: (i) Tb(m) is reduced from 230 K (uncoated) to 90 K (coated) for H = 2.5 mT (25 Oe); (ii) Decrease of Tb(m) with applied field H is much weaker for the uncoated particles and (iii) the ratio Tb(emr)/Tb(m) is smaller for the uncoated particles. These differences are interpreted in terms of the stronger interparticle interaction present in the uncoatedparticles.

Citation

Journal of Applied Physics

Volume

97

Pub Type

Journals

Keywords

electron microscopy, magnetic properties, nanoparticles

Citation

Seehra, M. , Shim, H. , Dutta, P. , Manivannan, A. and Bonevich, J. (2005), Interparticle Interaction Effects in the Magnetic Properities NiO Nanorods, Journal of Applied Physics (Accessed June 12, 2025)