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Title: Self-assembled periodic nanoporous network in multifunctional ZrO{sub 2}-CeO{sub 2}-(La{sub 0.8}Sr{sub 0.2})MnO{sub 3} composites

Abstract

This letter reports the structural characteristics of the self-assembled surface nanostructure in the 0.75 wt % (Zr{sub 0.88}Ce{sub 0.12})O{sub 2}-0.25 wt % (La{sub 0.8}Sr{sub 0.2})MnO{sub 3} ceramics. The surface consists of periodic porous network with islandlike structures occurring at the triple boundary junctions. The pores were found to have the diameter in the range of 150-200 nm with the thickness of the porous surface layer of the order of 100 nm. The pore distribution was quasiperiodic with the spacing in the range of 50-150 nm. The formation of the nanoporous network is correlated to the structural transformation occurring in ZrO{sub 2} system.

Authors:
; ; ; ;  [1];  [2];  [2]
  1. Materials Science and Engineering, University of Texas Arlington, Texas 76019 (United States)
  2. (United States)
Publication Date:
OSTI Identifier:
20960166
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 90; Journal Issue: 12; Other Information: DOI: 10.1063/1.2715111; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CERAMICS; CERIUM OXIDES; COMPOSITE MATERIALS; LANTHANUM COMPOUNDS; LAYERS; MANGANATES; NANOSTRUCTURES; PERIODICITY; POROUS MATERIALS; STRONTIUM COMPOUNDS; ZIRCONIUM OXIDES

Citation Formats

Sharma, Vaneet, Jiang, Jiechao, Hossu, Maria, Koymen, Ali R., Priya, Shashank, Department of Physics, University of Texas Arlington, Texas 76019, and Materials Science and Engineering, University of Texas Arlington, Texas 76019 and Automation and Robotics Research Institute, Fort Worth, Texas 76118. Self-assembled periodic nanoporous network in multifunctional ZrO{sub 2}-CeO{sub 2}-(La{sub 0.8}Sr{sub 0.2})MnO{sub 3} composites. United States: N. p., 2007. Web. doi:10.1063/1.2715111.
Sharma, Vaneet, Jiang, Jiechao, Hossu, Maria, Koymen, Ali R., Priya, Shashank, Department of Physics, University of Texas Arlington, Texas 76019, & Materials Science and Engineering, University of Texas Arlington, Texas 76019 and Automation and Robotics Research Institute, Fort Worth, Texas 76118. Self-assembled periodic nanoporous network in multifunctional ZrO{sub 2}-CeO{sub 2}-(La{sub 0.8}Sr{sub 0.2})MnO{sub 3} composites. United States. doi:10.1063/1.2715111.
Sharma, Vaneet, Jiang, Jiechao, Hossu, Maria, Koymen, Ali R., Priya, Shashank, Department of Physics, University of Texas Arlington, Texas 76019, and Materials Science and Engineering, University of Texas Arlington, Texas 76019 and Automation and Robotics Research Institute, Fort Worth, Texas 76118. Mon . "Self-assembled periodic nanoporous network in multifunctional ZrO{sub 2}-CeO{sub 2}-(La{sub 0.8}Sr{sub 0.2})MnO{sub 3} composites". United States. doi:10.1063/1.2715111.
@article{osti_20960166,
title = {Self-assembled periodic nanoporous network in multifunctional ZrO{sub 2}-CeO{sub 2}-(La{sub 0.8}Sr{sub 0.2})MnO{sub 3} composites},
author = {Sharma, Vaneet and Jiang, Jiechao and Hossu, Maria and Koymen, Ali R. and Priya, Shashank and Department of Physics, University of Texas Arlington, Texas 76019 and Materials Science and Engineering, University of Texas Arlington, Texas 76019 and Automation and Robotics Research Institute, Fort Worth, Texas 76118},
abstractNote = {This letter reports the structural characteristics of the self-assembled surface nanostructure in the 0.75 wt % (Zr{sub 0.88}Ce{sub 0.12})O{sub 2}-0.25 wt % (La{sub 0.8}Sr{sub 0.2})MnO{sub 3} ceramics. The surface consists of periodic porous network with islandlike structures occurring at the triple boundary junctions. The pores were found to have the diameter in the range of 150-200 nm with the thickness of the porous surface layer of the order of 100 nm. The pore distribution was quasiperiodic with the spacing in the range of 50-150 nm. The formation of the nanoporous network is correlated to the structural transformation occurring in ZrO{sub 2} system.},
doi = {10.1063/1.2715111},
journal = {Applied Physics Letters},
number = 12,
volume = 90,
place = {United States},
year = {Mon Mar 19 00:00:00 EDT 2007},
month = {Mon Mar 19 00:00:00 EDT 2007}
}
  • Preparation of YSZ film on La{sub 0.8}Sr{sub 0.2}MnO{sub 3} porous substrate was investigated using electrophoretic deposition (EPD) method. Since the electrical conductivity of La{sub 0.8}Sr{sub 0.2}MnO{sub 3} substrate is satisfactorily high at room temperature, YSZ powders were deposited electrophoretically on La{sub 0.8}Sr{sub 0.2}MnO{sub 3} substrate without any treatment such as metal coating. Open circuit voltage of SOFC where YSZ film prepared by EPD was applied, increased by repeating the deposition and calcination cycles. 6 or more times in repetitions were required to obtain YSZ film without gas leakage. A planar type SOFC fabricated by using Ni as anode, attained anmore » open circuit voltage and maximum power density of 1.0 V and 1.5 W/cm{sup 2}, respectively. It became evident that YSZ films without gas leakage can be prepared by the EPD method on LaMnO{sub 3} cathode substrates.« less
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  • The electronic valence state of Mn in Pb(Zr{sub 0.2}Ti{sub 0.8})O{sub 3}/La{sub 0.8}Sr{sub 0.2}MnO{sub 3} multiferroic heterostructures is probed by near edge x-ray absorption spectroscopy as a function of the ferroelectric polarization. We observe a temperature independent shift in the absorption edge of Mn associated with a change in valency induced by charge carrier modulation in the La{sub 0.8}Sr{sub 0.2}MnO{sub 3}, demonstrating the electronic origin of the magnetoelectric effect. Spectroscopic, magnetic, and electric characterization shows that the large magnetoelectric response originates from a modified interfacial spin configuration, opening a new pathway to the electronic control of spin in complex oxide materials.
  • High-resolution transmission electron microscopy (HREM) was used to identify a La(Sr)-deficient ordered nonstoichiometry in perovskite-like La{sub 0.8}Sr{sub 0.2}MnO{sub 3} which is used in solid oxide fuel cell technology. Experimental 400 kV HREM images were recorded in the crystal projections (112) and (110) with the objective lens defocused to {Delta}f = -40 nm and {Delta}f = -185 nm. They show very good agreement with simulated images which are based on an ideal perovskite structure with 12.5 {+-} 5% of the La(Sr) atoms being deficient on every second (111) plane. The actual rhombohedral distortion of La{sub 0.8}Sr{sub 0.2}MnO{sub 3} alone, as determinedmore » by X-ray diffraction, is not responsible for the observed HREM image contrasts. In addition, possible ordering of the strontium atoms could be excluded with the help of image simulations.« less
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