Evolution of magnetic and structural properties of TiO2 with Co-doping

Topal, Ugur
Ozkan, Husnu
Bakan, Halil I.
Cankur, Oktay
Topal, Kevser
This paper presents the phase formations and magnetic properties of Co-doped TiO2 synthesized by the colloidal and ammonium nitrate melt techniques (ANMT). The phase formations and ferromagnetic properties were studied with XRD and SQUID magnetometry. Crystallization of the TiO2 rutile lattice was completed at 1000 degrees C and that was preserved during annealing up to 1300 degrees C. For the samples annealed at 1200 degrees C, elemental analysis has shown that the colloidal technique leads to a single-phase rutile with cobalt concentration of almost nothing even in the initially 0.5 mol Co-added samples. Further increase of annealing temperature results in the appearance of other Ti-phases in addition to the rutile. On the other hand, it is quite interesting that these samples show ferromagnetic behavior. The samples synthesized by the ANMT method contain larger amounts of Co compared to the colloidal technique.


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In this paper an artificial neural network (ANN) has been developed to compute the magnetization of the pure and La-doped barium ferrite powders synthesized in ammonium nitrate melt. The input parameters were: the Fe/Ba ratio, La content, sintering temperature, HCl washing and applied magnetic field. A total of 8284 input data set from currently measured 35 different samples with different Fe/Ba ratios, La contents and washed or not washed in HCl were available. These data were used in the training set for ...
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The transformation kinetics and microstructural evolution during initial crystallization in highly driven Al(90)Sm(10) were investigated using transmission electron microscopy (TEM). conventional Cu K(alpha) and high-energy synchrotron X-ray diffraction (HEXRD) and differential scanning calorimetry (DSC). The highest cooling rate obtained in this study yielded a high number density of fcc-Al nanocrystals, with sizes on the order of 2-5 nm, embedded in a disordered matrix rich in an Al-Sm medium range order ...
Citation Formats
U. Topal, H. Ozkan, H. I. Bakan, O. Cankur, and K. Topal, “Evolution of magnetic and structural properties of TiO2 with Co-doping,” JOURNAL OF NON-CRYSTALLINE SOLIDS, pp. 1678–1682, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/68065.