Effect of titanium ion substitution in the barium hexaferrite studied by Mössbauer spectroscopy and X-ray diffraction

• Published in: Hyperfine interactions 2011-11, Vol.202 (1-3), p.97-106
• Main Authors: Quiroz, Pamela, Halbedel, Bernd, Bustamante, Angel, González, Juan C.
• Format: Article
• Language: English
• Subjects: Atomic; Condensed Matter Physics; Hadrons; Heavy Ions; Molecular; Nuclear Physics; Optical and Plasma Physics; Physics; Physics and Astronomy; Surfaces and Interfaces; Thin Films
• ISSN: 0304-3843; 1572-9540
• DOI: 10.1007/s10751-011-0361-1

A series of M-type barium hexaferrite has been synthesized in a glass melt by partially substituting the Fe 2 O 3 with TiO 2 for investigation of their structure. The glass melt has the basic composition (mol%): 40 BaO + 33 B 2 O 3 + (27-x) Fe 2 O 3 + x TiO 2 with x = 0, 3.6, 5.4 and 7.2 mol% TiO 2 . The substituted ferrites were studied by means of X-ray diffraction, Mössbauer spectroscopy and vibration sample magnetometer. X-ray diffraction studies revealed that not all samples have a single ferritic phase, a small second phase corresponding to BaTi 6 O 13 was also observed to form. The Mössbauer spectra changed from magnetically ordered (x = 0) to magnetically ordered with strong line broadening. Moreover, the broadening increases with TiO 2 content. The Mössbauer parameters suggested that Ti 4 +  occupies the 2a and 12k crystal sites, and the Ti 4 +  substitution on the 2b and 4f 2 site also occurs at high melt dopings. Therefore, coercivity and saturation magnetization decreased.