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Titanium dioxide nanoparticles were prepared by precipitation of aqueous TiCl₄ solution with ammonium hydroxide as precipitation agent. Freshly prepared Titania gel is allowed to crystallize under refluxing and stirring condition for 6 h over 90°C and oven dried over night in temperature above 100 C. X-ray diffraction studies on oven dried powder indicate formation of anatase phase TiO₂ with average crystalline size of 4.5 nm. Powders with variable amount of anatase and rutile phase were prepared by calcination of pure anatase in the temperature range 400-1000 c for 4 h. the XRD patterns show that phase transition from anatase to rutile occur in calcination above 600°C. The morphology and microstructure characteristics were obtained by XRD, TEM. and TGA.

Ceramic materials based on zirconium titanate prepared by sol-gel method are used extensively in microwave, telecommunications and catalysis. In order to investigate the effects of concentration of TTIP, a series of ZrO₂–TiO₂ mixed oxides was prepared by a modified sol–gel method and varying mole fraction of TTIP from 0.002, to 0.1. The samples were characterized by XRD, TG/DTA, and SEM. The XRD pattern of 370°C calcined samples showed the formation of TiO₂ phase. The optimum concentration of TTIP in the zirconia-titania mixed oxide in the precipitation solution was 0.032 for obtaining complete coating. Each oxide was calcined between 250 and 620°C. The results showed that concentration of TTIP have a pronounced effect on particle size of the calcined zirconium titanate (ZT) powders. The results showed that the surface area of the composite powder increased proper to monolithic ZrO2 powder.

The structural and morphology of copper-stabilized zirconia samples prepared by sol–gel techniques in different calcination time and temperature are reported. This research work has been proposed and verified that the calcination temperature and time strongly influenced the morphology as well as interaction between the active species and the support. The results obtained from the laboratory test indicate that cubic ZrO₂ and copper oxide are present in the structure if the calcination temperature is under 400°C. Cubic ZrO₂, tetragonal ZrO₂ with small amount of monoclinic ZrO₂, and CuO are formed after calcination at 500°C. Heating under 500°C will result in amorphous compounds being formed, suggesting that 500°C could be a phase transition point. The effect of calcination time is investigated by morphology and structural changes of CuO–ZrO₂ at 600°C during 2, 3.5, 5.5, 7.5, and 10 h. Incorporation of copper in ZrO₂ lattice results in a loss of order in the ZrO₂ structure when it is calcined. A further increase in the temperature of calcination leads to the phase changes in ZrO₂ structure.

With the miniaturization of electronic products, the portability and the critical need of clean energy for environment have led to the development of lead-free electroceramics. In this work, lead-free dielectric ceramics of 0.94Na${}_{0.5}$Bi${}_{0.5}$TiO₃–0.06BaTiO₃ (NBT–0.06BT) are synthesized by wet solid-phase method. The effects of calcination temperature on phase structure, morphology, densification behavior and dielectric properties are investigated. The XRD results indicate that all samples demonstrate typical diffraction peaks of perovskite structure. The SEM and dielectric analytical results show that high-performance dielectric property of NBT–0.06BT ceramic with dense microstructure and appropriate grain size can be achieved when the calcination temperature is appropriate.

In this work, Mn₂P₂O₇ nanoparticles were synthesized via hydrothermal route without any templates or surfactants followed by heat treatment at 700${}^{\circ }$C. The as-prepared samples were characterized and described using thermogravimetric and differential thermal analysis (TG-DTA), X-ray diffraction (XRD), Fourier transform infrared spectrometer (FT-IR), Scanning electron microscopy (SEM) analysis. The resultant product was evaluated for electrochemical properties in organic electrolyte between −1.4 and 1.6 V using cyclic voltammetry in ambient condition. It revealed the specific capacitance of 565 F/g at scan rate of 5 mV/s. The outstanding pseudocapacitive performance was absorbed due to the faradaic oxidation and reduction reactions related to the intercalation/de-intercalation of the tetrabutylammonium cation (TBA${}^{+})$ electrolyte and inorganic pyrophosphate lattice. It was believed that the cost effective Mn₂P₂O₇ nanoparticles may be promising electrode materials for electrochemical capacitors.

The rare-earth ion doping in nanocrystals has the advantage on improving the interested properties. As one of rare-earths, the trivalent samarium ion (Sm${}^{3+}$) was used as a dopant. The precursor of Sm${}^{3+}$-doped cadmium ferrite (CdFe₂O₄) nanocrystals was reacted in water-soluble polymeric nanoreactors as a dispersed phase in miniemulsion, and then calcinated to form doped nanocrystals. The 1% Sm${}^{3+}$-doped nanocrystal in small size exhibited the smaller narrow gap energy and weak photoluminescent emission intensity; which attributed to the positive influences on the photocatalytic degradation. The selected Sm${}^{3+}$-doped spinel ferrite nanocrystals provide a unique catalyzer for organic compound photodegradation.

Thin films of iron (Fe)-doped titanium dioxide (Fe:TiO${}_2)$ were prepared by sol–gel spin coating technique and further calcined at 450${}^{\circ }$C. The structural and optical properties of Fe-doped TiO₂ thin films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet–visible spectroscopy (UV–vis) and atomic force microscopic (AFM) techniques. The XRD results confirm the nanostructured TiO₂ thin films having crystalline nature with anatase phase. The characterization results show that the calcined thin films having high crystallinity and the effect of iron substitution lead to decreased crystallinity. The SEM investigations of Fe-doped TiO₂ films also gave evidence that the films were continuous spherical shaped particles with a nanometric range of grain size and film was porous in nature. AFM analysis establishes that the uniformity of the TiO₂ thin film with average roughness values. The optical measurements show that the films having high transparency in the visible region and the optical band gap energy of Fe-doped TiO₂ film with iron (Fe) decrease with increase in iron content. These important requirements for the Fe:TiO₂ films are to be used as window layers in solar cells.