Room temperature magnetization in Co-doped anatase phase of TiO2
2013 (English)In: European Physical Journal: Applied physics, ISSN 1286-0042, E-ISSN 1286-0050, Vol. 61, no 1, 10601- p.Article in journal (Refereed) Published
CoxTi1-xO2 films were deposited by spray pyrolysis technique on Si(1 0 0) substrates at 475 degrees C. A hydro-alcoholic solution containing titanium (iv) isopropoxide and Co(NO3)(2) with various Co doping levels from x = 0-0.015 in solution was used as spray solution. Grazing incident angle of X-ray diffraction illustrates that the CoxTi1-xO2 films are single phase and polycrystal with mixed orientations. Study of surface morphology of the films by atomic force microscope reveals that the annealing atmosphere does not significantly affect the grain size and the microstructure of the films. This study provides further insight into the importance of annealing atmosphere on magnetization of the films. Room temperature magneto-optical Kerr measurement was employed in polar mode. A hysteresis loop and a paramagnetic behavior have been recorded for samples annealed in H-2 ambient gas and air, respectively. Chemical composition analysis by X-ray photo-electron spectroscopy showed that Co atoms are bounded to oxygen and no metallic clusters are present. Moreover, it indicates the formation of high spin Co2+ for the sample x = 0.008 annealed in H-2 ambient gas. The origin of magnetization can be attributed to the contribution of oxygen vacancies in the spin polarization of the structure.
Place, publisher, year, edition, pages
2013. Vol. 61, no 1, 10601- p.
Natural Sciences Engineering and Technology
Research subject Engineering Science with specialization in Solid State Physics
IdentifiersURN: urn:nbn:se:uu:diva-196079DOI: 10.1051/epjap/2012120243ISI: 000314352800009OAI: oai:DiVA.org:uu-196079DiVA: diva2:609275