Preparation and studies of Co(II) and Co(III)-substituted barium ferrite prepared by sol–gel method

Electromagnetic Properties of Substituted Barium Hexaferrites

“…3+ sites [1][2][3][4][5]. Substitutions of Fe ions have a big influence, directly affecting the magnetic structure.…”

Structural and Magnetic Properties of BaCo<sub>x</sub>Fe<sub>12x</sub>O<sub>19</sub> (x = 0.2, 0.4, 0.6, &1.0) Nanoferrites Synthesized via Citrate Sol-Gel Method

“…It is well known that their structural and magnetic properties are closely connected to the distribution of Fe ions among various interstitial sites, and it has been found that these properties can be changed by doping of Fe 3+ and Ba 2+ with different types of cations and cation combinations. Due to this, researchers have a lot of interest in modifying structural, magnetic and electrical properties of nanoferrites, according to the requirement for various practical applications by different cation substitutions and by using different synthetic routes under varying conditions [7][8][9][10][11]. Sandaranarayanan et al [7] studied the effect of annealing temperature on Barium ferrites and reported that their crystallization begins around 550℃ and fully crystalline phase is obtained in the range of 700℃ -900℃.…”

“…Kresisel et al [9] reported that with increasing concentration of Co-Ti dopants in barium ferrites, axial anisotropy reduced and further changed to nearly planar magnetic anisotropy. Teh et al [10] synthesized Co 2+ and Co 3+ substituted Ba ferrites via sol-gel method and found that Co 2+ doping decreases the value of coercivity and saturation magnetisation significantly. However, Co 3+ doping shows less change in magnetic properties.…”

Tailored magnetic properties of Sm(Zn) substituted nanocrystalline barium hexaferrites

“…With the development of nanotechnology synthesizing, nanocrystalline hexaferrites could be prepared by many methods [6][7][8][9], such as sol-gel autocombustion, chemical co-precipitation, solid-state reaction, mechanical activation, low-temperature combustion, micro emulsion and reverse micro emulsion, ammonium nitrate melt technique, citrate-EDTA complexing method and so on. Due to the simple process and the controllable stoichiometric amounts, the sol-gel autocombustion method [10][11][12] was widely used to prepare nanocrystalline barium hexaferrites.…”

“…In order to improve the magnetic properties such as saturation magnetization (M s ) and coercivity (Hc), many studies have focused on the cationic substitution for nanocrystalline barium hexaferrites [10][11][12][13]. In M-type hexaferrites, the Fe 3+ occupies five different sites: the octahedral sites 2a, 12k, 4f 2 and the tetrahedral sites 2b, 4f.…”