In this research, a new polyurethane / Strontium hexaferrite / clinoptilolite (PU/SrM/CLP) nanocomposite was synthesized through the in-situ polymerization method, and its chemical stability in both acidic and alkaline solutions was assessed. It was found that the incorporation of CLP and SrM into the PU matrix would enhance the thermal stability of the nanomaterial. The thermal stability of the composite ingredients against the thermal events up to the temperature of 700 °C in an ascending order includes PU, Strontium hexaferrite, and CLP zeolite, respectively. As a result, the formed nanocomposite exhibited more thermal stability than PU. Several analytical techniques such as XRF, XRD, FTIR, SEM-EDX, and BET were employed to characterize the physicochemical properties of the nanocomposite. The presence of FTIR peaks at the wavelengths of 1700 cm-1 and 3400 cm-1 confirms the C=O and N–H groups due to the formation of PU in the composite structure, respectively. The pore volume and specific surface area of the Nano sorbent using BET were obtained as 0.5978 cm3/g and 2.60 m2/g, respectively. Based on the Scherrer equation, the adsorbent crystallite size was measured as 12.76 nm at the highest peak (100 %). In addition, The chemical stability of the prepared nanocomposite was assessed in both acidic and alkaline solutions which showed about a 12 % reduction. The point of zero charge (pHpzc) for nano sorbent was 7.4. According to the obtained results, the PU/SrM/CLP nanocomposite can be utilized as a stable and magnetic sorbent in aqueous harsh media, especially in wastewater samples.

We synthesized various types of barium and Strontium hexaferrite nanoparticles using barium chloride and Strontium nitrate salts by co-precipitation method in microwave. The solvent was either water, ethylene glycol or mixture of them with three different natural surfactants. XRD and SEM analysis were performed to evaluate the morphological characters of the products. The mean diameter of barium and Strontium hexaferrite particles in all products was less than 100 nm, indicating successful formation of nanoparticles. The purity of nanoparticles was documented by FT-IR spectrometry. SEM analysis shows that the nanostructures of products would change with respect to type of solvents and surfactants. So it is possible to change the size and structure of nanoparticles for various purposes with manipulation of primary parameters. In the second phase various proportions of barium chloride and Strontium nitrate were used for production of nanoproducts. All the products had pure nanoparticles of barium and Strontium hexaferrite which again was confirmed by XRD analysis. VSM analysis was performed to study the ferromagnetic characteristics of the products. Hysteresis curves disclosed that all the products have ferromagnetic properties. Strontium hexaferrite nanoparticles are hard ferromagnetics and barium hexaferrite nanoparticles are soft ferromagnetics and nanocomposite barium/Strontium hexaferrite nanoparticles have the intermediate ferromagnetic properties.

A sol-gel auto-combustion method using n-decyltrimethylammonium bromide as a cationic surfactant has been used to synthesize the Strontium hexaferrite powder. The gels were prepared from ferric and Strontium nitrates, citric acid and various molar ratios of surfactant to Strontium. Trimethylamine was used as a pH adjusting agent. The gels exhibited self-propagated combustion behavior after ignition in air. The combustion products were calcined at 800°C for 1 hour to form Strontium hexaferrite phase. The results showed that the optimum molar ratio of swjactant to Strontium in precursor is 0.4 and crystallite size of Strontium hexaferrite powder in this sample is 27.2 nm.

Strontium hexaferrite Bodies attracted more attention in various industries such as: microwave, Dc motors, agriculture (irrigation) and etc. In this research, the effect of chromium ion addition on phase analysis, microstructure and magnetic properties of Strontium hexaferrite bodies prepared by solid state synthesis have been investigated. Results show that not only molar ratio of iron oxide and Strontium oxide (n=6) but also first firing temperature (1210 oC) to form magnetic phase of Strontium hexaferrite and second firing temperature (1220 oC) to obtain suitable magnetic properties of Strontium hexaferrite bodies at presences of chromium must be considered. XRD and SEM investigations showed that optimum amount of chromium is 0.3 (SrCr0.3Fe11.7O19). Magnetic coercivity, remanent magnetization and rectangularity ratio (Hk/HCj) of sample were 3995 Oe, 3719 Gs and 83.5%, respectively.

Strontium hexaferrite nanocrystallites were prepared by the sol–gel autocombustion method followed by calcination at 900oC for 1h under different molar ratios of reductant/oxidant. The structural properties of Strontium hexaferrite nanoparticles were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the particle size of the resultant powder was about 50-80 nm. The photocatalytic activity of magnetic Strontium hexaferrite under UV light was evaluated using Methylene blue (MB) as a model compound for organic contaminants. The maximum degradation efficiency (46%) was achieved at molar ratio of reductant/oxidizer 0.8. Reasonably high values of magnetization, the Strontium hexaferrite nanoparticles could be easily separated from the environment by using a low strength magnetic field after the reaction.

Strontium hexaferrite (SrFe12O19) nanopowders have been synthesized using sol-gel auto combustion route. Ferrite precursors were obtained from aqueous mixtures of Strontium nitrate and ferric nitrate nonahydrate. Citric acid (C6H8O7), was added to the mixed solution as fuel. The effect of calcination temperature on the structural, morphological, magnetic properties and phase formation of synthesized SrFe12O19 nanopowder was investigated and discussed in details. The material properties were studied employing X-ray diffraction (XRD), Raman spectroscopy, SEM, and a vibrating-sample magnetometer (VSM). The calcined products and the formation of crystalline phase were analyzed via XRD technique which revealed the SrM single phase formation at calcined temperature 1100oC with a crystallite size of 76.107 nm. The Rietveld refinement technique as applied in the Fullprof program was utilized for determining the resulting crystalline phase’s amounts, lattice parameters, Bragg R-factor and refined structure value χ2. Raman analysis verified the development of the whole crystallographic hexaferrite locations and the whole peaks in the sample related to Raman vibration modes as well as M-type structures.   Additionally, the resulted outcomes verified that the prepared material was SrFe12O19 and its density (ρx) reduced as its calcination temperature increased up to 1100°C. The sample material’s magnetic analysis at the room temperature elucidated a higher coercivity value of (4610 Oe), a saturation magnetization of (66.285 emu/g), and a remnant of 38.90 emu/g.

In this research using starting materials of ferric nitrate, Strontium nitrate, citric acid and trimethylamine and by the sol-gel auto-combustion method, was produced Strontium hexaferrite powder. The effect of adding the hydrocarbon of tetrabutylammonium bromide and surfactant of n-decyltrimethyl ammonium bromide on the formation temperature and particles size of resultant powder was investigated. FTIR results showed the Occurrence of more complete combustion reaction in the samples with hydrocarbon and surfactant. According to the XRD results, single-phase Strontium hexaferrite is formed in sample without additive by calcination at 900°C, while in samples with hydrocarbon and surfactant formed at 850 and 800°C, respectively. With addition of surfactant, grains and particles size decreased significantly.