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An ongoing and elusive task is to create single phase anode materials for solid oxide fuel cells (SOFC). Compared to the typical Ni-YSZ cermet anode, perovskite oxide based anode material has a number of benefits. Here, we present the structural and electrical characteristics of Y3+ doped SrTiO3 ceramics that are used as the anode in solid oxide fuel cells. The samples with nominal composition x = 0 and 0.05 were synthesized by high energy ball milling. The powder X-ray diffraction pattern reveals that the synthesized samples crystallize into cubic crystal structure with space group Pm3m for both the compositions. The samples were sintered at a temperature of 1300 °C for 6h. The sintered density of the samples was found to be greater than 97%. The temperature dependent dielectric measurement studies reveal that dielectric constant increases with yttrium doping and shows relaxer behavior. A higher dielectric constant and electrical conductivity was observed for the Y-doped sample which fulfill the basic requirement for anode materials of solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

In this paper, an unexplored solid solution (1-x)Bi(Cu1/2Ti1/2)O3-(x)PbTiO3 has been synthesized and characterized for its crystal structure, dielectric and ferroelectric properties aimed at a selected composition, i.e., 0.30 Bi(Cu1/2Ti1/2)O3-0.70PbTiO3. The paper unveils the different synthesis approaches to achieve pure-phase in Pb-based perovskite-structured materials that are prone to produce impurities during synthesis. The Rietveld refinement of the XRD pattern confirms a tetragonal crystal structure (P4mm) of the composition. The ferroelectric properties of the as-prepared composition are also discussed using P-E hysteresis and PUND characteristics. The composition shows a high Tc (480 °C) and low dielectric losses, making it suitable for high-temperature applications. [ABSTRACT FROM AUTHOR]

We present the structural investigation on multiferroic Ba1-xSrxMnO3perovskite manganites with x = 0.50, 0.60, 0.70 and 0.75 synthesized by combustion method. Rietveld refinement of powder X-ray diffraction data reveals the hexagonal structure with space group P63/mmc for all compositions. The unit cell lattice parameters for Ba1-xSrxMnO3decrease monotonically with Sr-substitution on Ba-site. The value of structural tolerance factor decreases from 1.047 for x = 0.50 to 1.018 for x = 0.75. [ABSTRACT FROM PUBLISHER]

In this paper, an unexplored solid solution (1-x)Bi(Cu1/2Ti1/2)O3-(x)PbTiO3 has been synthesized and characterized for its crystal structure, dielectric and ferroelectric properties aimed at a selected composition, i.e., 0.30 Bi(Cu1/2Ti1/2)O3-0.70PbTiO3. The paper unveils the different synthesis approaches to achieve pure-phase in Pb-based perovskite-structured materials that are prone to produce impurities during synthesis. The Rietveld refinement of the XRD pattern confirms a tetragonal crystal structure (P4mm) of the composition. The ferroelectric properties of the as-prepared composition are also discussed using P-E hysteresis and PUND characteristics. The composition shows a high Tc (480 °C) and low dielectric losses, making it suitable for high-temperature applications. [ABSTRACT FROM AUTHOR]

Profile analysis of powder x-ray and neutron diffraction data on (1-x)[Pb(Mg 1/3 Nb 2/3 ) O 3 ]-xPbTiO 3 (PMN-xPT) confirms the presence of two monoclinic phases with space groups Cm and Pm in the morphotropic phase boundary (MPB) region sandwiched by the rhombohedral and tetragonal phase fields. The phase transition sequence R-M B -O-M C -T predicted by Vanderbilt and Cohen for 3π/ 4 [ABSTRACT FROM AUTHOR]

(1 - x)Pb(Fe 1/2 Nb 1/2 )O 3 -xPbTiO 3 (PFN-xPT) ceramics with x = 0.13 sintered at 1200°C show diffuse phase transition and very high dielectric constant at lower frequencies. The high value of dielectric constant at lower frequencies is shown to be due to the barrier layer formation. The resistivity of the PFN-xPT ceramics, obtained by complex impedance analysis, initially decreases with temperature and then shows an upward trend beyond the ferroelectric Curie point reminiscent of BaTiO 3 based thermistors with PTCR effect. [ABSTRACT FROM AUTHOR]