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This paper discusses the structural, microstructure, optical and electrical properties of perovskite CaSnO3 modified by Ti doping. Single phase of Ti-doped CaSnO3 was obtained using sol-gel method followed by calcination at 750 °C. X-ray diffraction and Fourier transform infrared spectroscopy techniques were used to probe Ti in the samples. Value of lattice parameters of all samples obtained from Rietveld refinement initially decreases with Ti-doping up to CSO5 and then slight increases for CSO7, due to difference in ionic radius between Ti4+ (0.61 Å) and Sn4+ (0.69 Å) and surface defect respectively. Using SEM, an average grain size of sintered samples was determined in the range of (0.38–1.02) μm. Because of the presence of dipole at large distances, the dielectric constant and tangent loss of samples was found to be independent of temperatures up to 300 °C, making it a potential candidate for thermally stable capacitor application. Nevertheless, the Arrhenius type conduction mechanism was found to be active in all samples with activation energy (0.41–0.68) eV, indicated that the conduction in samples occurred by transferring electrons between degenerate sites of Sn (Sn4+/Sn3+/Sn2+) and Ti (Ti4+/Ti3+/Ti2+). The P-E loop of CSO5 sample shows higher saturation polarization and coercive field than CSO0, making it a potential candidate for memory device application.

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Tetrahedral SBUs to construct 2D net having nanosized cavities.Five 2-D Ln(III) coordination polymers, [Ln(PDA)(PDAH)] n (PDA = 2,6-pyridinedicarboxylate), have been obtained under mild hydrothermal condition. In each coordination polymer, PDA is tetradentate and pentadentate, while lanthanides have coordination number eight to generate trigonal prismatic, triangular face bicapped LnO 6 N 2 geometry having 9 triangular and 2 square faces. Two different types of bridging oxygens are responsible to grow the 2-D coordination polymers providing open channels possessing infinite 1-D nanosized cavities. Adjacent 2-D chains are further extended to a 3-D hydrogen-bonded layered network through intermolecular π-π interactions and C-H⋯O hydrogen bonds. Four lanthanides are arranged roughly at the vertices of a square and bridged by eight carboxylates leading to the overall tetrahedral shape of the secondary building units. The abnormal behavior of lanthanide contraction for the atomic radii of europium can be attributed to overlapping of electron clouds. The overall magnetic behavior is typical for the presence of antiferromagnetic exchange coupling interactions. Thermal decomposition analysis reveals that the coordination polymers have significant thermal stability. The coordination polymers are further characterized using elemental analysis and FT-IR spectroscopy.

Bismuth ferrite (BFO) and (Yb, Co) co-doped BFO powder are successfully synthesized using the sol-gel method. The structural, electrical, magneto-dielectric and multiferroic properties of pure and co-doped BFO have been systematically investigated. The crystal structures of these samples are investigated using x-ray diffraction techniques, which confirmed the single-phase polycrystalline rhombohedral perovskite structure with the R3c space group. The co-substitution studies revealed that the electrical, ferromagnetic and ferroelectric properties of BFO were significantly enhanced compared to pure BFO samples.