Dielectric, pyroelectric, and ferroelectric studies in (1 - )AgNbO-FeNbO lead-free ceramics.

In the present study, the effect of heterovalent Fe ions on the dielectric, pyroelectric, and ferroelectric properties of the (1 - )AgNbO-FeNbO ( = 0.005, 0.01, 0.

Fabrication and Characterization of Dielectric ZnCrO Nanopowders and Thin Films for Parallel-Plate Capacitor Applications.

We report here the successful shape-controlled synthesis of dielectric spinel-type ZnCrO nanoparticles by using a simple sol-gel auto-combustion method followed by successive heat treatment steps of the resulting powders at temperatures from 500 to 900 °C and from 5 to 11 h, in air. A systematic study of the dependence of the morphology of the nanoparticles on the annealing time and temperature was performed by using field effect scanning electron microscopy (FE-SEM), powder X-ray diffraction (PXRD) and structure refinement by the Rietveld method, dynamic lattice analysis and broadband dielectric spectrometry, respectively. It was observed for the first time that when the aerobic post-synthesis heat treatment temperature increases progressively from 500 to 900 °C, the ZnCrO nanoparticles: (i) increase in size from 10 to 350 nm and (ii) develop well-defined facets, changing their shape from shapeless to truncated octahedrons and eventually pseudo-octahedra.

Enhanced energy storage performance in reaction-sintered AgNbO antiferroelectric ceramics.

In this research, AgNbO ceramics were produced by two sintering methods: reaction sintering (RS) and conventional solid-state sintering (CSSS). The process was similar for both methods, except that in RS, AgO and NbO precursors were mixed, then formed into pellets, skipping the calcination step, and sintered at 1100 °C for 6 hours. Both prepared ceramics had the same perovskite crystal structure with an orthorhombic crystal system and and 2 space groups with similar lattice dynamic vibration modes at room temperature.

GHz-THz Dielectric Properties of Flexible Matrix-Embedded BTO Nanoparticles.

BaTiO (BTO) nanoparticles produced by wet chemistry methods were embedded in several types of flexible materials in order to fabricate flexible electronic devices. Starting from the produced nanoparticle dielectric properties, flexible material dielectric properties were tested for high electromagnetic frequencies (30 GHz-2 THz) using time domain spectroscopy. Dielectric performances of the different materials obtained with variable nanoparticle concentrations up to 40 wt.

Crystal structure of poly[[di-aqua-tetra-μ-cyanido-platinum(II)iron(II)] methanol 4/3-solvate]: a three-dimensional Hofmann clathrate analogue.

In the title polymeric coordination compound, {[FePt(CN)(HO)]·1.33CHOH} , the Fe cation (site symmetry 4/) is coordinated by the N atoms of four cyanide anions (CN) and the O atoms of two water mol-ecules, forming a nearly regular [FeNO] octa-hedron. According the Fe-N and Fe-O bond lengths, the Fe atom is in the high-spin state.