Structural, magnetic and microwave absorption behavior of Co-Zr substituted strontium hexaferrites prepared using tartaric acid fuel for electromagnetic interference suppression

Effect of precursors on the structural, magnetic, dielectric, microwave and electromagnetic properties of Co–Zr doped nanocrystalline strontium hexaferrites synthesized via sol–gel method

“…LCR meter (Modelno.8714ET) was used to study the dielectric parameters whereas Agilent N5225A PNA series network analyzer was used for the measurement of complex permeability, complex permittivity and reflection loss in Kuband . A detailed account of characterization and physical measurements of powdered ferrites has been mentioned in earlier publications [8,9].…”

“…During present investigations we have employed ethylene glycol alone/simple sol-gel (series 1 [6]) as well as along with closely related poly-hydroxyl carboxylic acids which serve the dual function of a complexing agent and a fuel. Three different low-cost acids-citric acid (series 2 [7]), tartaric acid (series 3 [8]) and sucrose-gluconic acid (series 4 [9])-with different carbon bulk-C 3 , C 4 and C 12 respectively resulted in different combustion temperatures, different formation temperatures and hence in different properties of the final hexaferrites. Coupled substitution of divalent paramagnetic Co(II) and tetravalent diamagnetic Zr(IV) cations were applied because it allows the independent monitoring of saturation magnetization (M S ) and coercivity (H C ) for different applications.…”

“…Since among the four series, series 2 and 3 display the maximum and the minimum values of M S , respectively, their hysteresis loops are shown inFig. 6[7,8]. In these four series minimum M S and H C are obtained at 1.0 level of substitution with M S 56.76, 53.19, 54.42 and 49.71 emu/g, H C 1104.8, 2273.4, 1717.3 and 1796.5 Oe and M r 24.01, 24.78, 26.81 and 22.32 emu/g.…”

Tailoring conductive network nanostructures of ZIF-derived cobalt-decorated N-doped graphene/carbon nanotubes for microwave absorption applications

“…Amounts of researchers have chosen carbon-based materials [6][7][8][9], such as graphene and carbon nanotubes (CNTs), rather than ceramics [10,11] or conductive polymers [12][13][14][15], for their superior advantages including high electrical conductivity, low density, corrosion resistance, high carrier concentration, and adjustable nanostructures [16][17][18]. Magnetic loss behaviours can be mainly obtained by ferromagnetic particles (Fe, Co, Ni) and their alloy compounds [19][20][21]. However, the aggregation of magnetic particles at the nanoscale often exerts limited microwave absorption performance at low frequencies with a narrow absorption bandwidth, attributed to the Snoke's limit [22] around bulk magnetic materials.…”

Effect of Rare-Earth Co-Doping on the Microstructural and Magnetic Properties of BaFe12O19

“…In addition, co-doped Tm-Tb, Eu-Nd, Sm-Co Ba-hexaferrites have also been investigated and have been shown that co-doping of the rare-earth ions provides hexaferrites with a rise in the magnetization and/or coercivity [24][25][26][27]. Among other magnetic properties, some attempts have also been made to improve the maximum energy product, (BH)max for Srhexaferrites and Ba-hexaferrites using La-Sm [28,29].Researchers have different manufacturing methods to produce hexaferrites such as traditional ceramic methods [30][31][32][33][34] or several chemical methods [35][36][37][38][39][40][41].…”