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Abstract: A precipitate was formed when a aqueous solution of CaCl2, BiCl3, TaF5 and urea in stoichiometric ratio (total metal cations to urea ratio is 5) is heated on a water bath. This precipitate on decomposition at 600°C yielded the nanocrystallites of ternary oxide CaBi2Ta2O9 (CBT) as confirmed by X-ray diffraction (XRD). Particle size and morphology was studied by transmission electron spectroscopy (TEM). Ferroelectric hysteresis loop parameters such as remnant polarization (P r) and coercive field (E C) were also determined. TEM investigations revealed that the average particle size of the polycrystalline powder is 70nm. The room temperature dielectric constant was found to be 110. [Copyright &y& Elsevier]

Abstract: A simple co-precipitation technique had been successfully applied for the preparation of pure fine powders of single phase BaBi2Nb2O9. Ammonium hydroxide and ammonium oxalate were used to precipitate Ba2+, Bi3+ and Nb5+ cations simultaneously. No pyrochlore phase was formed while heating powder at 800°C and pure BaBi2Nb2O9 phase was found to be formed by X-ray diffraction (XRD). Particle size and morphology was studied by transmission electron spectroscopy (TEM). The room temperature dielectric constant at 1kHz is 100. The ferroelectric hysteresis loop parameters of these samples were also studied. [Copyright &y& Elsevier]

Abstract: A gel was formed when an aqueous solution of CaCl2, BiCl3, TaF5 and citric acid in stoichiometric ratio is heated on a water bath. This gel on decomposition at 600°C yielded the nano-crystallites of ternary oxide, CaBi2Ta2O9 (CBT) as confirmed by X-ray diffraction study (XRD). Particle size and morphology was studied by transmission electron spectroscopy (TEM). Ferroelectric hysteresis loop parameters such as remnant polarization (P r) and coercive field (E C) are also determined. TEM investigations revealed that the average particle size of the polycrystalline powder is 40nm. The room temperature dielectric constant was found to be 90. [Copyright &y& Elsevier]

A simple gel to crystal conversion route has been used for the preparation of Ce0.75Zr0.25O2 phase at 80–100°C under refluxing conditions. Freshly prepared metal hydroxides gel from cerium and zirconium salt solution is allowed to crystallize under refluxing and stirring conditions for 4–10h. Formation of nano crystallites of Ce0.75Zr0.25O2 is confirmed by X-ray diffraction (XRD). Transmission electron microscopy (TEM) investigations revealed the average particle size of these powders to be 5nm. [Copyright &y& Elsevier]

Abstract: A gel was formed when a aqueous solution of BaCl2, BiCl3, NbF5 and citric acid in stoichiometric ratio is heated on a water bath. This gel on decomposition at 600 °C produced the nanocrystallites of ternary oxide, BaBi2Nb2O9 (BBN). The phase contents and lattice parameters were studied by the powder X-ray diffraction (XRD). Particle size and morphology was studied by transmission electron spectroscopy (TEM). The room temperature dielectric constant at 1 kHz is 90 °C. The ferroelectric hysteresis loop parameters of these samples were also studied by a home built Sawyer–Tower circuit. [Copyright &y& Elsevier]

Abstract: A combination of digestion and further low temperature calcination to crystallize the product is employed to prepare BaNb2O6 ceramics. Freshly prepared niobium hydroxide gel is mixed with barium hydroxide thoroughly and allowed to react at 100 °C under refluxing and stirring conditions for 6–12 h. The X-ray amorphous product so formed is heated at 500 °C to form crystalline BaNb2O6. This is the lowest temperature so far reported for the formation of BaNb2O6. Transmission electron microscope (TEM) investigations revealed that the average particle size is 50 nm for the calcined powders. The room temperature dielectric constant at 1 kHz is found to be 600. The ferroelectric hysteresis loop parameters of these samples were also studied. [Copyright &y& Elsevier]

A gel was formed when an aqueous mixture of Ce(NO3)3·6H2O, ZrOCl2·8H2O and citric acid is heated on a water bath. Ultrafine powders of Ce0.75Zr0.25O2 phase are found to be formed when the gel was decomposed at 673 K. These powders are characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and surface area measurements. Low-angle XRD studies show the formation of a mesoporous structure (d=22.64 Å).The average particle size obtained by TEM investigations is 3.5 nm. [Copyright &y& Elsevier]