Interesting magnetic behavior from reduced titanium dioxide nanobelts

作者：Shen V. Chong, K. Kadowaki, J. Xia, Hicham Idriss · 发表于：Applied Physics Letters · 年份：2008 · DOI：10.1063/1.2944141 · 被引用次数：38 · 研究领域：ZnO doping and properties、Electronic and Structural Properties of Oxides、Multiferroics and related materials

The magnetic behavior of titanium dioxide nanobelts has been investigated with and without Co doping. Room temperature ferromagnetism was observed when the Co-doped anatase TiO2 nanobelts were prepared via vacuum annealing of 2.5at.% Co-doped titanate nanobelts, while annealing them in air resulted in paramagnetic ordering. Interestingly, by vacuum annealing the undoped titanate nanobelts under the same conditions, superparamagnetic ordering was observed in the resulting anatase TiO2 nanobelts. The electron paramagnetic resonance of this latter sample shows a strong symmetrical signal at g=2.003 suggesting some sort of exchange interactions among the localized electrons’ spin moments from single electron trapped in oxygen vacancies.