Work

ε-Fe2O3: An Advanced Nanomaterial Exhibiting Giant Coercive Field, Millimeter-Wave Ferromagnetic Resonance, and Magnetoelectric Coupling

Year: 2010

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide Nanosized iron oxides still attract significant attention within the scientific community, because of their application-promising properties. Among them, ε-Fe 2 O 3 constitutes a remarkable phase, taking pride in a giant coercive field at room temperature, significant ferromagnetic resonance, and coupled magnetoelectric features that are not observed in any other simple metal oxide phase. In this work, we review basic structural and magnetic characteristics of this extraordinary nanomaterial with an emphasis on questionable and unresolved issues raised during its intense research in the past years. We show how a combination of various experimental techniques brings essential and valuable information, with regard to understanding the physicochemical properties of the ε-polymorph of Fe 2 O 3, which remained unexplored for a long period of time. In addition, we recapitulate a series of synthetic routes that lead to the formation of ε-Fe 2 O 3, highlighting their advantages and drawbacks. We also demonstrate how magnetic properties of ε-Fe 2 O 3 can be tuned through the exploitation of various morphologies of ε-Fe 2 O 3 nanosystems, the alignment of ε-Fe 2 O 3 nanoobjects in a supporting matrix, and various degrees of cation substitution. Based on the current knowledge of the scientific community working in the field of ε-Fe 2 O 3, we finally arrive at two main future challenges: (i) the search for optimal synthetic conditions to prepare single-phase ε-Fe 2 O 3 with a high yield, desired size, morphology, and stability; and (ii) the search for a correct description of the magnetic behavior of ε-Fe 2 O 3 at temperatures below the characteristic magnetic ordering temperature.

Source: Chemistry of Materials

DOI: 10.1021/cm101967h

Authors: Jiří Tuček, Radek Zbořil, Asuka Namai, Shin-ichi Ohkoshi

Institutions: Regional Centre of Advanced Technologies and Materials, Palacký University Olomouc, The University of Tokyo

Language: English

Topic: Magnetic Properties and Synthesis of Ferrites

Subfield: Materials Chemistry

Field: Materials Science

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,500

Funder: Japan Society for the Promotion of Science