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Abstract: Zirconium titanate powders were synthesized by a straightforward sol–gel method using zirconium and titanium chlorides as metal precursors, deionized water as solvent and oxygen donor, and a NaOH solution for adjusting pH to 7. According to transmission electron microscopy, amorphous particles of nearly 5nm in size with a relatively spherical morphology were prepared. Thermogravimetry and differential scanning calorimetery analyses on the xerogel at a heating rate of 10°C/min indicated a crystallization temperature of 690°C, which is comparable with previous reports. Furthermore, via differential scanning calorimetery studies using the Kissinger''s equation, the activation energy for ZrTiO4 crystallization was determined to be 850kJ/mol. Structural evaluations in the isothermal regime, using X-ray diffraction experiments, implied the onset of ZrTiO4 crystallization at 550°C. [Copyright &y& Elsevier]

Abstract: This work focuses on the effect of aluminum content, grain size and additive materials, including silicon dioxide (SiO2) and calcium oxide (CaO) on the magnetic properties of the Al-substituted nickel ferrite produced by conventional ceramic technique. The magnetic and electrical properties of samples were measured by an inductance/capacitance/resistance meter; moreover, the morphology and structure of the samples were characterized by scanning electron microscopy and X-ray diffraction, respectively. Results show that, magnetic permeability, Curie temperature, equivalent series resistance, lattice parameter and average grain size decrease as the Al content increases. In addition, by adding additive materials, such as CaO and SiO2, the average grain size and magnetic permeability increase. [Copyright &y& Elsevier]

Abstract: This work investigates the synthesis of Al-substituted nickel ferrite by powder conventional method with different Al contents with x=0.0, 0.1, 0.2, 0.3, 0.4 and 0.5 (NiAlxFe2−xO4). X-ray diffraction, scanning electron microscopy, vibrating sample magnetometry and measurement of inductance–capacitance–resistance were carried out at room temperature to study the structural, magnetic and electrical properties. The structural analysis reveals that the lattice parameter and the grain size decrease as the Al content increases. The magnetic and electrical measurements show that the saturation magnetization, Curie point, coercivity and equivalent series resistance decrease by increasing the Al content. [Copyright &y& Elsevier]