skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Structural and conductivity studies of CsK(SO{sub 4}){sub 0.32}(SeO{sub 4}){sub 0.68}Te(OH){sub 6}

Abstract

The compound CsK(SO{sub 4}){sub 0.32}(SeO{sub 4}){sub 0.68}Te(OH){sub 6} crystallizes in the monoclinic P2{sub 1}/n space group. It was analyzed, at room temperature, using X-ray diffractometer data. The main feature of these atomic arrangements is the coexistence of three and different anions (SO{sub 4}{sup 2-}, SeO{sub 4}{sup 2-} and TeO{sub 6}{sup 6-}groups) in the unit cell, connected by hydrogen bonds which make the building of the crystal. The thermal analysis of the title compound shows three distinct endothermal peaks at 435, 460 and 475 K. Complex impedance measurements are performed on this material as a function of both temperature and frequency. The electric conduction has been studied. The temperature dependence on the conductivity indicates that the sample became an ionic conductor at high temperature. - Graphical abstract: Projection of crystal structure CsK(SO{sub 4}){sub 0.32}(SeO{sub 4}){sub 0.68}Te(OH){sub 6} on the ab plane. Highlights: Black-Right-Pointing-Pointer We have studied the results of the crystal structure of the new mixed compound. Black-Right-Pointing-Pointer We have characterized the phase transition observed in DSC curve. Black-Right-Pointing-Pointer The protonic conduction in our material is probably due to a hopping mechanism.

Authors:
 [1];  [1];  [2];  [3];  [1];  [1]
  1. Laboratoire de Chimie Inorganique, Universite de Sfax, Faculte des Sciences de Sfax, BP 1171, 3000 Sfax (Tunisia)
  2. (France)
  3. Laboratoire de l'Etat solide, Universite de Sfax, Faculte des Sciences de Sfax, BP 1171, 3000 Sfax (Tunisia)
Publication Date:
OSTI Identifier:
22149941
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Solid State Chemistry; Journal Volume: 196; Other Information: Copyright (c) 2012 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CALORIMETRY; CRYSTALS; DIELECTRIC PROPERTIES; MONOCLINIC LATTICES; PHASE TRANSFORMATIONS; POTASSIUM COMPLEXES; SELENATES; SPACE GROUPS; SULFATES; SUPERCONDUCTIVITY; TEMPERATURE DEPENDENCE; THERMAL ANALYSIS; X-RAY DIFFRACTION; X-RAY DIFFRACTOMETERS

Citation Formats

Djemel, M., E-mail: jmal_manel@yahoo.fr, Abdelhedi, M., E-mail: m_abdelhedi2002@yahoo.fr, Laboratoire Leon Brouillon, CE/Saclay, 91191 Gif-Sur-Yvette Cedex, Zouari, N., E-mail: bizrirl@yahoo.fr, Dammak, M., E-mail: meddammak@yahoo.fr, and Kolsi, A.W., E-mail: kolsi_abdelhwaheb@yahoo.fr. Structural and conductivity studies of CsK(SO{sub 4}){sub 0.32}(SeO{sub 4}){sub 0.68}Te(OH){sub 6}. United States: N. p., 2012. Web. doi:10.1016/J.JSSC.2012.06.040.
Djemel, M., E-mail: jmal_manel@yahoo.fr, Abdelhedi, M., E-mail: m_abdelhedi2002@yahoo.fr, Laboratoire Leon Brouillon, CE/Saclay, 91191 Gif-Sur-Yvette Cedex, Zouari, N., E-mail: bizrirl@yahoo.fr, Dammak, M., E-mail: meddammak@yahoo.fr, & Kolsi, A.W., E-mail: kolsi_abdelhwaheb@yahoo.fr. Structural and conductivity studies of CsK(SO{sub 4}){sub 0.32}(SeO{sub 4}){sub 0.68}Te(OH){sub 6}. United States. doi:10.1016/J.JSSC.2012.06.040.
Djemel, M., E-mail: jmal_manel@yahoo.fr, Abdelhedi, M., E-mail: m_abdelhedi2002@yahoo.fr, Laboratoire Leon Brouillon, CE/Saclay, 91191 Gif-Sur-Yvette Cedex, Zouari, N., E-mail: bizrirl@yahoo.fr, Dammak, M., E-mail: meddammak@yahoo.fr, and Kolsi, A.W., E-mail: kolsi_abdelhwaheb@yahoo.fr. 2012. "Structural and conductivity studies of CsK(SO{sub 4}){sub 0.32}(SeO{sub 4}){sub 0.68}Te(OH){sub 6}". United States. doi:10.1016/J.JSSC.2012.06.040.
@article{osti_22149941,
title = {Structural and conductivity studies of CsK(SO{sub 4}){sub 0.32}(SeO{sub 4}){sub 0.68}Te(OH){sub 6}},
author = {Djemel, M., E-mail: jmal_manel@yahoo.fr and Abdelhedi, M., E-mail: m_abdelhedi2002@yahoo.fr and Laboratoire Leon Brouillon, CE/Saclay, 91191 Gif-Sur-Yvette Cedex and Zouari, N., E-mail: bizrirl@yahoo.fr and Dammak, M., E-mail: meddammak@yahoo.fr and Kolsi, A.W., E-mail: kolsi_abdelhwaheb@yahoo.fr},
abstractNote = {The compound CsK(SO{sub 4}){sub 0.32}(SeO{sub 4}){sub 0.68}Te(OH){sub 6} crystallizes in the monoclinic P2{sub 1}/n space group. It was analyzed, at room temperature, using X-ray diffractometer data. The main feature of these atomic arrangements is the coexistence of three and different anions (SO{sub 4}{sup 2-}, SeO{sub 4}{sup 2-} and TeO{sub 6}{sup 6-}groups) in the unit cell, connected by hydrogen bonds which make the building of the crystal. The thermal analysis of the title compound shows three distinct endothermal peaks at 435, 460 and 475 K. Complex impedance measurements are performed on this material as a function of both temperature and frequency. The electric conduction has been studied. The temperature dependence on the conductivity indicates that the sample became an ionic conductor at high temperature. - Graphical abstract: Projection of crystal structure CsK(SO{sub 4}){sub 0.32}(SeO{sub 4}){sub 0.68}Te(OH){sub 6} on the ab plane. Highlights: Black-Right-Pointing-Pointer We have studied the results of the crystal structure of the new mixed compound. Black-Right-Pointing-Pointer We have characterized the phase transition observed in DSC curve. Black-Right-Pointing-Pointer The protonic conduction in our material is probably due to a hopping mechanism.},
doi = {10.1016/J.JSSC.2012.06.040},
journal = {Journal of Solid State Chemistry},
number = ,
volume = 196,
place = {United States},
year = 2012,
month =
}
  • Recent progress in the development of high-performance, 0.6-eV Ga{sub 0.32}In{sub 0.68}As/InAs{sub 0.32}P{sub 0.68} thermophotovoltaic (TPV) converters and monolithically interconnected modules (MIMs) is described. The converter structure design is based on using a lattice-matched InAs{sub 0.32}P{sub 0.68}/Ga{sub 0.32}In{sub 0.68}As/InAs{sub 0.32}P{sub 0.68} double-heterostructure (DH) device, which is grown lattice-mismatched on an InP substrate, with an intervening compositionally step-graded region of InAs{sub y}P{sub 1{minus}y}. The Ga{sub 0.32}In{sub 0.68}As alloy has a room-temperature band gap of {approximately}0.6 eV and contains a p/n junction. The InAs{sub 0.32}P{sub 0.68} layers have a room-temperature band gap of {approximately}0.96 eV and serve as passivation/confinement layers for the Ga{submore » 0.32}In{sub 0.68}As p/n junction. InAs{sub y}P{sub 1{minus}y} step grades have yielded DH converters with superior electronic quality and performance characteristics. Details of the microstructure of the converters are presented. Converters prepared for this work were grown by atmospheric-pressure metalorganic vapor-phase epitaxy (APMOVPE) and were processed using a combination of photolithography, wet-chemical etching, and conventional metal and insulator deposition techniques. Excellent performance characteristics have been demonstrated for the 0.6-eV TPV converters. Additionally, the implementation of MIM technology in these converters has been highly successful. {copyright} {ital 1999 American Institute of Physics.}« less
  • Thermophotovoltaic (TPV) systems have recently rekindled a high level of interest for a number of applications. In order to meet the requirement of low-temperature ({approximately}1000&hthinsp;{degree}C) TPV systems, 0.6-eV Ga{sub 0.32}In{sub 0.68}As/InAs{sub 0.32}P{sub 0.68} TPV monolithically interconnected modules (MIMs) have been developed at the National Renewable energy Laboratory (NREL) [1]. The successful fabrication of Ga{sub 0.32}In{sub 0.68}As/InAs{sub 0.32}P{sub 0.68} MIMs depends on developing and optimizing of several key processes. Some results regarding the chemical vapor deposition (CVD)-SiO{sub 2} insulating layer, selective chemical etch via sidewall profiles, double-layer antireflection coatings, and metallization via interconnects have previously been given elsewhere [2]. In thismore » paper, we report on the study of contacts and back-surface reflectors. In the first part of this paper, Ti/Pd/Ag and Cr/Pd/Ag contact to n-InAs{sub 0.32}P{sub 0.68} and p-Ga{sub 0.32}In{sub 0.68}As are investigated. The transfer length method (TLM) was used for measuring of specific contact resistance R{sub c}. The dependence of R{sub c} on different doping levels and different pre-treatment of the two semiconductors will be reported. Also, the adhesion and the thermal stability of Ti/Pd/Ag and Cr/Pd/Ag contacts to n-InAs{sub 0.32}P{sub 0.68} and p-Ga{sub 0.32}In{sub 0.68}As will be presented. In the second part of this paper, we discuss an optimum back-surface reflector (BSR) that has been developed for 0.6-eV Ga{sub 0.32}In{sub 0.68}As/InAs{sub 0.32}P{sub 0.68} TPV MIM devices. The optimum BSR consists of three layers: {approximately}1300 {Angstrom} MgF{sub 2} (or {approximately}1300 {Angstrom} CVD SiO{sub 2}) dielectric layer, {approximately}25 {Angstrom} Ti adhesion layer, and {approximately}1500 {Angstrom} Au reflection layer. This optimum BSR has high reflectance, good adhesion, and excellent thermal stability. {copyright} {ital 1999 American Institute of Physics.}« less
  • Dielectric anomalies observed in heterostructures of the epitaxial thin films of (PbMg{sub 1/3}Nb{sub 2/3}O{sub 3}){sub 0.68}-(PbTiO{sub 3}){sub 0.32}, fabricated by in situ pulsed laser deposition on La{sub 0.5}Sr{sub 0.5}CoO{sub 3}/MgO (100), and with metal top electrodes, were analyzed. The contribution of the film-electrode interfaces to the properties of the heterostructures was evaluated and the true properties of the films were reconstructed. Deviation from Curie-Weiss behavior, temperature evolution of the local order parameter, the Vogel-Fulcher relationship, and temperature evolution of the relaxation time spectrum were found in the films. The relaxor ferroelectric properties of the films were essentially similar to thosemore » of the single crystal. Also, it was shown that an apparent {open_quotes}relaxorlike{close_quotes} behavior in ferroelectric thin film heterostructures, evidenced only by a broad maximum and frequency dispersion of the dielectric permittivity, can be determined by the film-electrode interface rather than by the relaxor properties of the films.« less
  • An experimental and theoretical study has been carried out of the temperature dependent noise and responsivity performance of n-type x = 0.32 Hg{sub 1{minus}x}Cd{sub x}Te photoconductors. The fundamental noise sources that ultimately limit the specific detectivity, D*{sub {lambda}}, at the three main temperatures of interest are identified and correlated with the experimental material parameters of the device. A device model is presented for the responsivity and noise voltage which takes into account surface effects such as surface recombination and accumulation layer shunting. For a given set of device and material parameters this model is well able to account for themore » observed experimental values of responsivity and noise voltage over the full temperature range from 80--300 K. Using a theoretical model, it is shown that under ideal conditions it is possible to achieve background limited performance at temperatures up to 210 K. Experimental results are presented for responsivity, noise voltage, semiconductor surface charge density and D*{sub {lambda}} for a frontside-illuminated Hg{sub 1{minus}x} Cd{sub x} Te photoconductive detector, as a function of temperature in the range 80--300 K. The devices were fabricated on Liquid Phase Epitaxially (LPE) grown n-type Hg{sub 0.68}Cd{sub 0.32}Te, and were passivated with anodic oxide/ZnS on the front side.« less