Crystal-structure analysis, Raman spectroscopy, dielectric measurements, magnetic and optical properties of Cr3+–Ni2+-substituted Co2Y-type barium hexaferrites

Ultra-broadband microwave absorption of (Mn0.2Fe0.2Zn1.2)x substituted Co2Y hexaferrites with a self-aligned sheet stacked, highly c-axis oriented and multi-domain structure

“…As shown in Table 1, both a and c increase with the increase of substitution x, and the c/a ratio obtained from Rietveld rened samples uctuates between 7.419 and 7.423. Suthar M. 28 and Carol T. T. T. 29 also reported similar results in the presence of La 3+ -Mg 2+ substituted Y-type barium hexaferrites and Cr 3+ -Ni 2+ substituted Co 2 Y type barium hexaferrites, respectively. The lattice constants (a and c) increase because Fe 2+ (0.77 Å), Zn 2+ (0.745 Å) and Mn 2+ (0.82 Å) ions are all larger than the substituted Co 2+ (0.735 Å).…”

Recent Progress in Hexagonal Ferrites Based Composites for Microwave Absorption

“…[70,114] The structure of y-type is said to be an alternate stacking of tetrahedral (T), and spinel (S) blocks parallel to the caxis with space group R-3m [115][116][117][118][119] and a = 5.9 Å and c = 43.5 Å as lattice parameters. [120,121] The formula for Y-type is A 2 M 2 Fe 12 O 22 , where A can be Ba or Sr and M is any divalent metal ion [122,123] and are attractive prospects for microwave device applications at high-frequency. [124][125][126][127][128][129] Proper choice of Me ion and substitutions for Fe 3+ ions improve the properties of Y-type hexaferrite.…”