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Title: Characterizing chemical stability and proton conductivity of B-site doped barium hafnate (BaHfO 3 ) and barium stannate (BaSnO 3 ) with first principles modeling

Authors:
;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1399150
Resource Type:
Journal Article: Publisher's Accepted Manuscript
Journal Name:
Journal of Alloys and Compounds
Additional Journal Information:
Journal Volume: 693; Journal Issue: C; Related Information: CHORUS Timestamp: 2017-10-11 20:38:44; Journal ID: ISSN 0925-8388
Publisher:
Elsevier
Country of Publication:
Netherlands
Language:
English

Citation Formats

Kang, Sung Gu, and Sholl, David S. Characterizing chemical stability and proton conductivity of B-site doped barium hafnate (BaHfO 3 ) and barium stannate (BaSnO 3 ) with first principles modeling. Netherlands: N. p., 2017. Web. doi:10.1016/j.jallcom.2016.09.221.
Kang, Sung Gu, & Sholl, David S. Characterizing chemical stability and proton conductivity of B-site doped barium hafnate (BaHfO 3 ) and barium stannate (BaSnO 3 ) with first principles modeling. Netherlands. doi:10.1016/j.jallcom.2016.09.221.
Kang, Sung Gu, and Sholl, David S. Wed . "Characterizing chemical stability and proton conductivity of B-site doped barium hafnate (BaHfO 3 ) and barium stannate (BaSnO 3 ) with first principles modeling". Netherlands. doi:10.1016/j.jallcom.2016.09.221.
@article{osti_1399150,
title = {Characterizing chemical stability and proton conductivity of B-site doped barium hafnate (BaHfO 3 ) and barium stannate (BaSnO 3 ) with first principles modeling},
author = {Kang, Sung Gu and Sholl, David S.},
abstractNote = {},
doi = {10.1016/j.jallcom.2016.09.221},
journal = {Journal of Alloys and Compounds},
number = C,
volume = 693,
place = {Netherlands},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1016/j.jallcom.2016.09.221

Citation Metrics:
Cited by: 4works
Citation information provided by
Web of Science

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  • Lead-free barium stannate titanate ceramics doped with 2 wt% of B{sub 2}O{sub 3} were prepared via a solid state sintering. The optimum condition for the preparation was carried out. Properties of the lead free material were characterized by various methods. The high dielectric constant >14000 with low tan delta 0.040 was observed at 34 deg. C for the samples prepared at the optimum condition. Plots of dielectric permittivity as a function of temperature showed that the ceramics exhibit a diffuse ferroelectric-paraelectric phase transition. The dielectric constant was also measured as a function of electric field. The dielectric-electric field measurement indicatedmore » that this material exhibits a high tunability. In addition, mechanical property such as hardness was investigated. Relation between grain size and hardness of the ceramics was found to obey the Hall-Petch equation: H{sub v} = 0.07+12.9G{sup -(1/2)}.« less
  • Room temperature ferromagnetism was observed in Mn-doped zinc stannate (ZTO:Mn) nanowires, which were prepared by chemical vapor transport. Structural and magnetic properties and Mn chemical states of ZTO:Mn nanowires were investigated by X-ray diffraction, superconducting quantum interference device (SQUID) magnetometry and X-ray photoelectron spectroscopy. Manganese predominantly existed as Mn{sup 2+} and substituted for Zn (Mn{sub Zn}) in ZTO:Mn. This conclusion was supported by first-principles calculations. Mn{sub Zn} in ZTO:Mn had a lower formation energy than that of Mn substituted for Sn (Mn{sub Sn}). The nearest neighbor Mn{sub Zn} in ZTO stabilized ferromagnetic coupling. This observation supported the experimental results.
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