Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1596541 | Solid State Communications | 2006 | 5 Pages |
Abstract
In recent work, we have shown that chemically synthesized Sn1âxCoxO2 nanoscale powders with xâ¤0.01 are ferromagnetic at room temperature when prepared by annealing the reaction precipitate in the narrow temperature window of 350-600 âC. Combined high resolution x-ray photoelectron spectroscopy (on as-prepared and Ar+ ion sputtered samples), x-ray diffraction and magnetometry measurements showed that the Co distribution is more uniform throughout the individual Sn0.99Co0.01O2 particles when prepared at lower annealing temperatures of 350-600 âC and this uniform dopant distribution is essential to produce stable high temperature ferromagnetism. However, surface segregation of the dopant atoms in samples annealed at >600 âC destroys the room-temperature ferromagnetic behavior and reduces the Curie temperature to <300 K.
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Physical Sciences and Engineering
Materials Science
Materials Science (General)
Authors
A. Punnoose, M.H. Engelhard, J. Hays,