Large Coercive Field of 45 kOe in a Magnetic Film Based on Metal-Substituted ε-Iron Oxide

Shin-Ichi Ohkoshi; Kenta Imoto; Asuka Namai; Shizuka Anan; Marie Yoshikiyo; Hiroko Tokoro

doi:10.1021/jacs.7b07087

Large Coercive Field of 45 kOe in a Magnetic Film Based on Metal-Substituted ε-Iron Oxide

J Am Chem Soc. 2017 Sep 27;139(38):13268-13271. doi: 10.1021/jacs.7b07087. Epub 2017 Sep 13.

Authors

Shin-Ichi Ohkoshi^{1

2}, Kenta Imoto¹, Asuka Namai¹, Shizuka Anan¹, Marie Yoshikiyo¹, Hiroko Tokoro^{1

3}

Affiliations

¹ Department of Chemistry, School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
² Cryogenic Research Center, The University of Tokyo , 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
³ Division of Materials Science, Faculty of Pure and Applied Sciences, University of Tsukuba , 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8573, Japan.

PMID: 28901752
DOI: 10.1021/jacs.7b07087

Abstract

Magnetic ferrites are stable, sustainable, and economical. Consequently, they have been used in various fields. The development of large coercive field (large H_c) magnetic ferrites is a very important but challenging issue to accelerate the spread of use and to expand practical applications. In this study, we prepared a rhodium-substituted ε-iron oxide film and observed a remarkably large H_c value of 35 kOe at room temperature. This is the largest value among magnetic ferrites to date. Such a large-H_c ferrite is expected to greatly expand the application of magnetic ferrites. Furthermore, when the temperature dependence of the magnetic properties was measured, an even larger H_c value of 45 kOe was recorded at 200 K. Such large H_c values are much larger than those of conventional hard magnetic ferrites.

Publication types

Research Support, Non-U.S. Gov't