Effect of Cobalt on the Magnetic Properties of the LiFe1−xCoxO2 Layered System (0≤x≤1)

✍ Scribed by E. Chappel; M. Holzapfel; G. Chouteau; A. Ott

• Publisher: Elsevier Science
• Year: 2000
• Tongue: English
• Weight: 240 KB
• Volume: 154
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1006/jssc.2000.8864

✦ Synopsis

Layered LiFe1؊xCoxO2 was prepared in the whole composition range by ion-exchange reaction in a molten eutectic mixture of LiCl and LiNO3 at 2603C. The magnetic properties were studied by means of magnetic susceptibility and high-5eld magnetization measurements. Layered LiFeO2 exhibits a NeH el temperature of TN‫02؍‬ K. Some cationic disorder is present but seems to have no e4ect on the magnetic properties. The saturation magnetization and the number of e4ective Bohr magnetons are consistent with the high spin state (S‫؍‬ 5

2 ) of the Fe 3؉ ion. A two sublattice model consisting of antiferromagnetic order between ferromagnetic layers is proposed with an estimation of the ferro-and antiferromagnetic interactions. Replacing iron by cobalt leads to an increase of the Weiss temperature up to x ‫؍‬ 0.4 but at the same time the antiferromagnetic long-range order is destroyed. The e4ect of cobalt on the superexchange interactions is also discussed.