کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1329379 | 978907 | 2009 | 6 صفحه PDF | دانلود رایگان |
Co-doped anatase and rutile bulk-samples prepared by the sol–gel technique are found to be paramagnetic at room-temperature. Only further annealing in Ar/H2 gas results in a ferromagnetic behavior. X-ray diffraction and electron-microscope studies reveal for low doping levels <4% the formation of Co-doped rutile samples and the formation of CoTiO3 as a new phase. Co3O4 can be detected in anatase samples with Co doping levels ⩾4%. The observed Co oxides are reduced by Ar/H2 to Co metal. The room-temperature ferromagnetism can therefore be traced back to a segregation of metallic Co.
Co-doped anatase and rutile bulk-samples prepared by the sol-gel technique are paramagnetic at room-temperature. Further annealing in Ar/H2 gas results in a ferromagnetic behavior. X-ray diffraction and electron-microscope (SEM, BSE) studies reveal for low doping levels <4% the formation of Co-doped rutile samples and of CoTiO3 as a new phase. Co3O4 is found in anatase samples with Co doping levels ⩾4%. The observed Co oxides are reduced by Ar/H2 to Co metal. The room-temperature ferromagnetism can be traced back to a segregation of metallic CoFigure optionsDownload as PowerPoint slide
Journal: Journal of Solid State Chemistry - Volume 182, Issue 4, April 2009, Pages 942–947