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Commercial Barium Titanate BaTiO3 (BT) is milled by planetary ball mill in acetone medium using stainless steel bowl & ball for different hours. BT is an important perovskite oxide with structure ABO3. BT has applications in electro-optic devices, energy storing devices such as photovoltaic cells, thermistors, multiceramic capacitors & DRAMs etc. BT is non-toxic & environment friendly ceramic with high dielectric and piezoelectric property so it can be used as the substitute of PZT & PbTiO3. Here, we have investigated the effect of milling time and temperature on particle size and phase transition of BT powder. We used use Raman spectroscopy for studying the spectra of BT; XRD is used for structural study. Intensity (height) of Raman spectra and XRD spectra continuously decrease with increasing the milling hours and width if these spectra increases which indicates, decrease in BT size. [ABSTRACT FROM AUTHOR]

Herein, Eu3+- Dy3+-Ce3+ tri-doped SrSnO3 have been prepared by conventional sol-gel method. XRD analysis confirmed its orthorhombic phase with Pnma (62) space group symmetry. The morphology of the sample is flake like which has examined by SEM. SrSnO3 consists of several vibrational modes due to Sn-O bond which was analysed by Fourier transform Infrared (FTIR) spectra. Photoluminescence (PL) emission and excitation spectra have been recorded for optical analysis. It consist characteristic emission peaks of Ce3+, Dy3+ and Eu3. The intensity of 590 nm emission increases with increasing Eu3+ concentration and it is maximum for 3 at% Eu3+ co-doped sample. The CIE chromaticity co-ordinates are found near white region so it would be a promising phosphor for white LEDs. [ABSTRACT FROM AUTHOR]

Recently, organic- inorganic perovskite materials have attracted much attention due to their enormous potential for use in future of new sustainable energy sources. However, fabrication of environmental friendly perovskite and achieving better stability is a major concern towards the commercialization. Here we study the role of cations in the perovskite powder and their influence upon thermodynamic stability. In this study we find, inorganic (cesium, Cs+) cation is shown to be more efficient in the thermal stabilization of the perovskite material than organic (methylamine, CH3NH2+) cation. This study reviles that stability of perovskite can be improved by incorporation of inorganic cation. [ABSTRACT FROM AUTHOR]

(1-x)PVDF-xBa(Fe1/2Nb1/2)O3 ceramic-polymer composites with x = 0.025, 0.05, 0.10, 0.15 were prepared using melt-mixing technique. The crystal symmetry, space group and unit cell dimensions were determined from the XRD data of Ba(Fe1/2Nb1/2)O3 using FullProf software, whereas crystallite size and lattice strain were estimated using Williamson-Hall approach. The distribution of Ba(Fe1/2Nb1/2)O3 particles in the PVDF matrix were examined on the cryo-fractured surfaces using a scanning electron microscope. Cole-Cole and pseudo Cole-Cole analysis suggested the dielectric relaxation in this system to be of non-Debye type. Filler concentration dependent real and imaginary parts of dielectric constant as well as ac conductivity data followed definite trends of exponential growth types of variation. [ABSTRACT FROM AUTHOR]

CH3NH3PbI3 is a newly developed organic inorganic perovskite light harvesting (OIPLH) material which is using for different electronic applications. In this work, we have synthesized CH3NH3PbI3 with different ratio of precursor CH3NH3I and PbI2. We have tried to explain how the ratio of precursors affected the crystallinity and thermal stability of OIPLH material. XRD study of material shows that, crystallinity of material losses on increasing the precursor ratio and simultaneous thermal analysis (TGA/DTA) indicates the more thermal decomposition with increasing precursor ratio due to excess amount of CH3NH3I. [ABSTRACT FROM AUTHOR]

CH3NH3PbI3 is a newly developed organic inorganic perovskite light harvesting (OIPLH) material which is using for different electronic applications. In this work, we have synthesized CH3NH3PbI3 with different ratio of precursor CH3NH3I and PbI2. We have tried to explain how the ratio of precursors affected the crystallinity and thermal stability of OIPLH material. XRD study of material shows that, crystallinity of material losses on increasing the precursor ratio and simultaneous thermal analysis (TGA/DTA) indicates the more thermal decomposition with increasing precursor ratio due to excess amount of CH3NH3I. [ABSTRACT FROM AUTHOR]

The master sintering curve (MSC) of K0.5Na0.5NbO3 (KNN) ceramics was constructed using constant heating rate dilatometry data based on the combined stage sintering model. The linear shrinkage was recorded using three heating rates 5 °C, 7 °C and 11 °C/ min. The obtained results suggest that in MSC, the sintered density is a unique function of the integral of a temperature function over time and it is independent of the sintering history. The MSC theory can be applied to predict shrinkage and final density. Also, it can be used to design a reproducible process to fabricate ceramics with required density. [ABSTRACT FROM AUTHOR]

Lead free phase pure K0.5Na0.5NbO3 ceramic has been synthesized using colloidal coating method. The coated sample is calcined at 800 °C and sintered at 1100 °C. The sintered product showed more than 95% of theoretical density. The SEM micrograph showed uniform, dense and well developed microstructure. The maximum dielectric constant ([variant_greek_epsilon]r = 11043) showed marked improvement over conventionally prepared samples and has been attributed to uniform mixing and homogeneous composition. [ABSTRACT FROM AUTHOR]