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The structural, morphological and optical properties of solvothermally synthesized Pr(OH)(3) nanoparticles and calcined Pr6O11 nanorods have been studied. Pr6O11 nanorods were grown by subsequent thermal decomposition of the synthesized Pr(OH)(3) nanoparticles at 700 degrees C for 2 h. Structural analysis showed that the synthesized Pr(OH)(3) nanoparticles possess hexagonal phase and calcined Pr6O11 nanorods have cubic fluorite phase. HRSEM images revealed that the Pr6O11 sample contains well-defined rod-like morphology. The UV-vis absorbance study of Pr6O11 nanorods showed shapedependent absorption edge toward higher wavelength as compared to Pr(OH)(3) nanoparticles. The PL spectrum of Pr6O11 nanorods reveals the enhanced near-band-edge emission in the blue region, with significant defect level green emission. The mechanism for the formation of Pr6O11 nanorods from Pr(OH)(3) nanoparticles has been proposed., QC 20140404

A facile co-precipitation route has been employed to synthesize cerium oxide (CeO2) nanoparticles using cationic surfactant (tetradecyltrimethyl ammonium bromide, C(14)TAB) and cerium nitrate hexahydrate at room temperature. X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscope (TEM), selected area electron diffraction (SAED), fourier transform infrared spectroscopy (FT-IR), UV-vis spectrophotometer and photoluminescence spectroscopy (PL) were employed to characterize the as-prepared sample. The XRD pattern showed cubic fluorite structure of CeO2 without any impurity peaks, revealing high purity of the sample. The lattice strain experienced by the sample was analyzed using Williamson-Hall plot. FTIR studies confirmed the presence of C(14)TAB on the CeO2 nanoparticles. TEM revealed that the as-prepared CeO2 sample consists of uniform particles with particle size of 10 nm. The red shift phenomenon was observed in UV-vis spectrum, which was further supported by PL studies., QC 20140327

Zirconia toughened alumina (ZTA) nanocomposites with different zirconia contents (5-20 mol%) were prepared by the sol-gel method. The prepared composites were sintered at 1300 °C by both conventional and microwave techniques. The crystallinity, average grain size, microstructure and densification of the samples prepared by conventional and microwave sintering methods were compared. X-ray diffraction analysis shows that the microwave sintered samples possess higher tetragonality and also exhibit reduced particle size compared to conventional sintering. HR-SEM surface micrograph reveals that the microwave sintered samples have homogeneous particle size distribution with less degree of porosity. TEM analysis confirms uniform distribution of particles with an average particle size of 20 nm for the microwave sintered sample. SAED pattern reveals that the microwave sintered samples possess improved crystallinity compared to conventional sintered samples. The apparent porosity and density of ZTA nanocomposites measured for different zirconia contents show that the densification of 97% could be achieved for the microwave sintered samples with higher content of zirconium

Zirconia toughened alumina (ZTA) nanocomposites with different zirconia contents (5-20 mol%) were prepared by the sol-gel method. The prepared composites were sintered at 1300 °C by both conventional and microwave techniques. The crystallinity, average grain size, microstructure and densification of the samples prepared by conventional and microwave sintering methods were compared. X-ray diffraction analysis shows that the microwave sintered samples possess higher tetragonality and also exhibit reduced particle size compared to conventional sintering. HR-SEM surface micrograph reveals that the microwave sintered samples have homogeneous particle size distribution with less degree of porosity. TEM analysis confirms uniform distribution of particles with an average particle size of 20 nm for the microwave sintered sample. SAED pattern reveals that the microwave sintered samples possess improved crystallinity compared to conventional sintered samples. The apparent porosity and density of ZTA nanocomposites measured for different zirconia contents show that the densification of 97% could be achieved for the microwave sintered samples with higher content of zirconium

Zirconia toughened alumina (ZTA) nanocomposites with different zirconia contents (5-20 mol%) were prepared by the sol-gel method. The prepared composites were sintered at 1300 °C by both conventional and microwave techniques. The crystallinity, average grain size, microstructure and densification of the samples prepared by conventional and microwave sintering methods were compared. X-ray diffraction analysis shows that the microwave sintered samples possess higher tetragonality and also exhibit reduced particle size compared to conventional sintering. HR-SEM surface micrograph reveals that the microwave sintered samples have homogeneous particle size distribution with less degree of porosity. TEM analysis confirms uniform distribution of particles with an average particle size of 20 nm for the microwave sintered sample. SAED pattern reveals that the microwave sintered samples possess improved crystallinity compared to conventional sintered samples. The apparent porosity and density of ZTA nanocomposites measured for different zirconia contents show that the densification of 97% could be achieved for the microwave sintered samples with higher content of zirconium

Zirconia toughened alumina (ZTA) nanocomposites with different zirconia contents (5-20 mol%) were prepared by the sol-gel method. The prepared composites were sintered at 1300 °C by both conventional and microwave techniques. The crystallinity, average grain size, microstructure and densification of the samples prepared by conventional and microwave sintering methods were compared. X-ray diffraction analysis shows that the microwave sintered samples possess higher tetragonality and also exhibit reduced particle size compared to conventional sintering. HR-SEM surface micrograph reveals that the microwave sintered samples have homogeneous particle size distribution with less degree of porosity. TEM analysis confirms uniform distribution of particles with an average particle size of 20 nm for the microwave sintered sample. SAED pattern reveals that the microwave sintered samples possess improved crystallinity compared to conventional sintered samples. The apparent porosity and density of ZTA nanocomposites measured for different zirconia contents show that the densification of 97% could be achieved for the microwave sintered samples with higher content of zirconium

Lead free piezoelectric single crystals of sodium potassium niobate (K0.5Na0.5)NbO3 single crystals were grown by high-temperature solution method using B2O3 flux. The KNN crystals grown by without B2O3 flux and with B2O3 flux are referred to as samples A and B respectively. It was found that additions of small amounts of boron oxide B2O3 further lower the melting temperature of the eutectic mixture and exhibits excellent dielectric properties. Phase analysis showed that all samples crystallized in pure orthorhombic perovskite phase. AFM morphological studies show that the root mean square (rms) roughness values were measured to be, 5.3nm and 6.96nm for the sample A and sample B crystal respectively. A slight decrease in the orthorhombic to tetragonal phase transition temperature T(O-T) and Curie temperature T-C has been observed in sample B when compared with sample A., QC 20221004