XAS study of Ti0.9Fe0.1O2-ä oxides obtainded by mechanosynthesis.

CLAUDIA RODRíGUEZ TORRES, A. FABIANA CABRERA, LEONARDO ERRICO, AND FRANCISCO SáNCHEZ

Campinas, Brasil

Congreso; 16th Reunión Anual de usuarios del LNLS; 2006

Laboratorio Nacional de luz sincrotron (LNLS) - Ministerio de Ciencia y Tecnología de Brasil

Diluted magnetic semiconductors (DMS) are interesting materials due to their potential applications as magneto optics devices and in technologies based on spintronics. Besides that, bulk DMS materials are of interest in its own, because the origin of the observed ferromagnetism remains an issue of discussions. Co doped TiO2 is the most studied DMS with a Curie temperature above 400K [1]. Theoretical results [2] also pointed out that Fe could be used as potential dopants for semiconducting oxides. In this work we study the possibility to obtained Fe doped rutile by mechanosynthesis. The final objective is to study the local environment of the magnetic impurities and to relate it with the magnetic properties of the obtained samples. Powders of TiO2 and hematite, with nominal composition Ti0.9Fe0.1O2-ä, were ball milled in a horizontal vibratory mill during 2.5, 5 and 10 h in air. The samples were characterized by XAFS, XRD, Mossbauer spectroscopy (MS) and vibrating sample magnetometry (VSM).     [1] Y. Matsumoto et al. Science 291, 854 (2001). [2] L. Errico et al. Phys.Stat. Sol B 241, 2399 (2004).