Improved magnetic properties of Cr3+ doped SrFe12O19 synthesized via microwave hydrothermal route. (March 2015)

• Record Type: Journal Article
• Authors: Katlakunta, Sadhana; Meena, Sher Singh; Srinath, S.; Bououdina, M.; Sandhya, R.; Praveena, K.
• Is Part Of: Materials research bulletin. Volume 63(2015:Mar.)
• Page Start: 58
• Page End: 66
• Publication Date: 2015-03
• Subjects: A. Magnetic materials -- B. Chemical synthesis -- C. Mössbauer spectroscopy -- C. Photoelectron spectroscopy -- D. Magnetic properties; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2014.11.043
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: The sintering temperature was lowered as the samples were prepared by M–H method. By increasing Cr 3+ concentration, the shape of the grains changed from platelet hexagonal to pyramidal. XPS spectra showed the presence of both Fe 2+ and Fe 3+ ions in the Cr doped hexaferrite structure. With Cr 3+ addition, M S decreased and H C increased. Abstract: Cr doped Sr-hexaferrites (SrCr x Fe12− x O19 ) were prepared using microwave-hydrothermal method and sintered at 950 °C/90 min using single mode microwave furnace. With increasing Cr 3+ content, the lattice parameters changed anisotropically, where ' a ' increases and ' c ' decreases. The average grain sizes of sintered hexaferrite are in the range of 280–660 nm. XPS spectra shows that for higher Cr 3+ content i.e., x > 0.3, both Fe 2+ and Fe 3+ ions are present in the crystal structure. With Cr 3+ doping saturation magnetization systematically decreased and coercivity increased. Magnetic hyperfine analysis using Mössbauer technique indicates that Cr 3+ ions preferentially occupy 2 a, 12 k, and 4 f 1 sites.