Morphological and magnetic properties of sol-gel synthetized meso and macroporous spheres of barium hexaferrite (BaFe12O19)
| Autor: | S. Torres-Cadenas, Alejandro Bravo-Patiño, I. Betancourt, M.E. Contreras-García, José Reyes-Gasga |
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| Rok vydání: | 2017 |
| Předmět: |
Materials science
Scanning electron microscope 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics 01 natural sciences 0104 chemical sciences Electronic Optical and Magnetic Materials law.invention Crystal Ferromagnetism Chemical engineering law Transmission electron microscopy Calcination 0210 nano-technology High-resolution transmission electron microscopy Mesoporous material Sol-gel |
| Zdroj: | Journal of Magnetism and Magnetic Materials. 432:410-417 |
| ISSN: | 0304-8853 |
| DOI: | 10.1016/j.jmmm.2017.02.018 |
| Popis: | Porous spherical aggregates of barium hexaferrite (BaFe 12 O 19 ) with 1.5 µm in diameter were synthetized by the surfactant-assisted sol-gel method. The surfactant Tween20 (C 58 H 114 O 26 ), which enables mesoporous structures, as well as polystyrene spheres (PS), as the template agent for the formation of macropores, were used. Two synthetic routes (hereafter named A and B), whose difference was the absence or presence of PS, were followed for synthesis. X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) in high resolution mode (HRTEM) were used for characterization. Size and morphology of the spheres were similar in both cases and they resemble a nest or ball-of-yarn type structure. Pore size and BaFe 12 O 19 crystal size produced by the two routes are different. The magnetic properties of the spheres were evaluated using a vibrating sample magnetometer (VSM) as function of the calcination temperature. The spheres present ferromagnetic behavior in both routes. |
| Databáze: | OpenAIRE |
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