Department of Chemistry, School of Science, The University of Tokyo , 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Cryogenic Research Center, The University of Tokyo , 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan.
J Am Chem Soc. 2017 Sep 27;139(38):13268-13271. doi: 10.1021/jacs.7b07087. Epub 2017 Sep 13.
Magnetic ferrites are stable, sustainable, and economical. Consequently, they have been used in various fields. The development of large coercive field (large H) 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 value of 35 kOe at room temperature. This is the largest value among magnetic ferrites to date. Such a large-H 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 value of 45 kOe was recorded at 200 K. Such large H values are much larger than those of conventional hard magnetic ferrites.
磁性铁氧体稳定、可持续且经济，因此被广泛应用于各个领域。开发具有高矫顽力（高 H）的磁性铁氧体是一个非常重要但具有挑战性的问题，它可以加速其应用的普及并拓展其实际应用。在这项研究中，我们制备了一种铑取代的 ε- 氧化铁薄膜，并在室温下观察到了 35 千奥斯特（kOe）的显著高 H 值。这是迄今为止磁性铁氧体中的最大数值。这种高 H 值的铁氧体有望极大地拓展磁性铁氧体的应用。此外，当测量磁性性能的温度依赖性时，在 200 K 下记录到了甚至更高的 45 kOe 的 H 值。这样的大 H 值远远大于传统硬磁性铁氧体的值。
