Abstract

In this paper, we demonstrate that films of magnetite, Fe3O4, can be deposited by the electrochemical reduction of a Fe(III)-triethanolamine complex in aqueous alkaline solution. the films were deposited with a columnar microstructure and a [100] preferred orientation on stainless steel substrates. In-plane electrical transport and magnetoresistance measurements were performed on the films after they were stripped off onto glass substrates. the resistance of the films was dependent on the oxygen partial pressure. We attribute the increase in resistance in O2 and the decrease in resistance in Ar to the oxidation and reduction of grain boundaries. the decrease in resistance in an Ar atmosphere exhibited first-order kinetics, with an activation energy of 0.2 eV. the temperature dependence of the resistance showed a linear dependence of log(R) versus T-1/2, consistent with tunneling across resistive grain boundaries. a room-temperature magnetoresistance of -6.5% was observed at a magnetic field of 9 T.

Department(s)

Chemistry

Sponsor(s)

National Science Foundation (U.S.)
United States. Department of Energy

Comments

This work was supported by National Science Foundation Grant Nos. CHE-0243424, CHE-0437346, and DMR-0504715, and Department of Energy Grant No. DE-FC07-03ID14509.

Keywords and Phrases

Electrochemical deposition; Magnetite

International Standard Serial Number (ISSN)

0884-2914

Document Type

Article - Journal

Document Version

Final Version

File Type

text

Language(s)

English

Rights

© 2006 Materials Research Society (MRS), All rights reserved.

Publication Date

01 Jan 2006

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