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SrFe12O19 samples were initially prepared using sol-gel auto-combustion method and calcined from 500 to 1100°C (for 6 h). XRD data established the phase formation temperature of SrM phase to be ≈1000°C. Thereafter, the effect of Zn2+-Zr4+ co-dopant on magnetic and structural properties of SrZnxZrxFe12-2xO19 (x = 0.00–1.00) samples calcined between 900–1100°C was investigated. XRD data shows that the cell volume increases (from 690.45Å3 (x = 0.00) to 705.72Å3 (x = 1.00)) while crystallite size decreases (from 123.9 nm (x = 0.00) to 62.3nm (x = 1.00)) calcined at 1000°C. The Rietveld refinement of XRD data confirms a) x = 0.00 sample to be phase pure and b) the presence of ZnFe2O4 (≈2.25) & SrZrO3 (≈2.93%) impurity phases in x = 1.00 sample, calcined at 1000°C. FESEM micrographs revealed that a) grain size decreases for x > 0.20 with `x’ at 900°C and b) increases from 122 nm at 900°C to 443 nm at 1100°C, for x = 0.00. Broadening of Raman bands reveals generation of strain in the lattice with enhancement of Zn2+-Zr4+ concentration. The magnetic studies reveal that the coercivity monotonically decreases (from 5358(x = 0.00) Oe to 690(x = 1.00) Oe at 1000°C) with enhancement of Zn2+-Zr4+ concentration. A maximum Ms value ≈ 70.89 emu/g was observed in x = 0.20 sample at 1100°C. Ms value also decreases for x > 0.20 at each calcination temperature.

The major objective of the present investigation to study the effect of Zn/Zr dopant on M type-barium hexagonal ferrites on structure and properties. During present work, we have synthesized a series of BaZnxZrxFe(12-₂x)O19 ferrites (x=0, 0.1, 0.3, 0.5, 0.7, and 0.9) using sol-gel auto combustion method using citric acid as fuel and precursor was calcined at 900°C for 6 hour. These compounds were characterized by FTIR, XRD, VSM, TEM. XRD data of Barium hexaferrite (BAM) material reveals pure phase and have no traces of intermediate phase such as α/γ –Fe2O3 and BaCO3. The BaM series crystal size ranging from 38.9 to 66.9 nm and average size of particle is 49.7 nm. FTIR analysis give information about the functional groups and molecular bands present in the calcined barium hexaferrite material. Magnetic measurements reveal that the values of coercivity ranges viz Hc 4875Oe (x = 0) to 835Oe (x=0.9). The saturation magnetization (Ms) values are in the range of 58.2 to 33.4 emu/g.

High permeance membranes selective towards small ions and solutes are required to produce high-quality product water. Conventional semi-aromatic polyamide thin-film composite (TFC) nanofiltration membranes prepared via interfacial polymerization of diamine, e.g., piperazine (PIP) and acid chloride, do not show the precise separation of small solutes (

Synthesis of BaZn0.6Zr0.6Fe10.8O19 powder samples using sol–gel-auto-combustion method has been reported. The impact of calcination temperature on the structural, magnetic and surface morphology of these samples has been investigated. XRD data confirms that the samples are phase pure and have no traces of intermediate phase such as α/γ-Fe2O3 and BaCO3 etc. The lattice parameters and cell volume increase slightly with increase in calcination temperature. The c/a parameter is

We report the synthesis of Ba0.5Sr0.5ZnxZrxFe12-2xO19 (x = 0.00–1.00) samples using sol–gel auto combustion method. The Rietveld refinement of XRD data indicates a) pure phase formation, b) increase in lattice parameters with composition and c) the absence of undesirable phases such as α–Fe2O3, BaCO3 and SrCO3. FESEM and TEM micrographs reveal an increase in grain size with ‘x’. The broadening of Raman peaks without any peak shift in all the samples indicates that the Zn2+/Zr4+ions are incorporated into Ba0.5Sr0.5Fe12O19 without altering the local structure. Magnetic measurements reveal that the maximum value of saturation magnetization (Ms) is 67.37 emu/g in x = 0.4 sample. The coercivity (Hc) monotonically decreases from 4.936 KOe to 1.029 KOe with increasing concentration of non-magnetic dopants. The dielectric constant values decreases monotonically as function of frequency for all the samples. The samples because of their superior magnetic properties could be vital for high density perpendicular recording, high density parallel recording EM shielding and permanent magnet applications.