Structural effects in the protonic/electronic conductivity of dion-jacobson phase niobate and tantalate layered perovskites

Yoji Kobayashi, Joshua A. Schottenfeld, Digby D. Macdonald, Thomas E. Mallouk

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

The layered Dion-Jacobson phase perovskites HLaTa2O 7·xH2O, HLaNb2O7·0. 5H2O and structural variants of HLaNb2O 7·0.5H2O were prepared and their AC and DC conductivities were measured as a function of temperature and atmosphere. The layered structure in HLaNb2O7·0.5H2O was modified by pillaring, exfoliation-restacking, and further annealing. Exfoliation followed by restacking markedly increased the ionic conductivity, either by creation of mesopores for hydration or by enhanced contact between layers, but pillaring had little effect. HLaNb2O7· 0.5H2O was prone to reduction under hydrogen, yielding a mixed ionic-electronic conductor. In-plane conductivity measurements of an oriented film of HLaNb2O7·0.5H2O showed enhanced ionic conductivity attributed to the anisotropic conductivity of the sheets, but reduction under a hydrogen atmosphere was apparent. The reduction could be suppressed by adding water vapor to the ambient atmosphere or by replacing the B-site niobium with tantalum, which is less easily reduced.

Original languageEnglish (US)
Pages (from-to)3185-3191
Number of pages7
JournalJournal of Physical Chemistry C
Volume111
Issue number7
DOIs
StatePublished - Feb 22 2007

Fingerprint

niobates
perovskites
Ionic conductivity
atmospheres
conductivity
ion currents
Hydrogen
Niobium
electronics
Tantalum
Steam
hydrogen
tantalum
niobium
Hydration
Water vapor
hydration
water vapor
alternating current
conductors

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Energy(all)
  • Physical and Theoretical Chemistry
  • Surfaces, Coatings and Films

Cite this

Kobayashi, Yoji ; Schottenfeld, Joshua A. ; Macdonald, Digby D. ; Mallouk, Thomas E. / Structural effects in the protonic/electronic conductivity of dion-jacobson phase niobate and tantalate layered perovskites. In: Journal of Physical Chemistry C. 2007 ; Vol. 111, No. 7. pp. 3185-3191.
@article{9c9afc9ac35441109a0caa6147a342c1,
title = "Structural effects in the protonic/electronic conductivity of dion-jacobson phase niobate and tantalate layered perovskites",
abstract = "The layered Dion-Jacobson phase perovskites HLaTa2O 7·xH2O, HLaNb2O7·0. 5H2O and structural variants of HLaNb2O 7·0.5H2O were prepared and their AC and DC conductivities were measured as a function of temperature and atmosphere. The layered structure in HLaNb2O7·0.5H2O was modified by pillaring, exfoliation-restacking, and further annealing. Exfoliation followed by restacking markedly increased the ionic conductivity, either by creation of mesopores for hydration or by enhanced contact between layers, but pillaring had little effect. HLaNb2O7· 0.5H2O was prone to reduction under hydrogen, yielding a mixed ionic-electronic conductor. In-plane conductivity measurements of an oriented film of HLaNb2O7·0.5H2O showed enhanced ionic conductivity attributed to the anisotropic conductivity of the sheets, but reduction under a hydrogen atmosphere was apparent. The reduction could be suppressed by adding water vapor to the ambient atmosphere or by replacing the B-site niobium with tantalum, which is less easily reduced.",
author = "Yoji Kobayashi and Schottenfeld, {Joshua A.} and Macdonald, {Digby D.} and Mallouk, {Thomas E.}",
year = "2007",
month = "2",
day = "22",
doi = "10.1021/jp063061d",
language = "English (US)",
volume = "111",
pages = "3185--3191",
journal = "Journal of Physical Chemistry C",
issn = "1932-7447",
publisher = "American Chemical Society",
number = "7",

}

Structural effects in the protonic/electronic conductivity of dion-jacobson phase niobate and tantalate layered perovskites. / Kobayashi, Yoji; Schottenfeld, Joshua A.; Macdonald, Digby D.; Mallouk, Thomas E.

In: Journal of Physical Chemistry C, Vol. 111, No. 7, 22.02.2007, p. 3185-3191.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Structural effects in the protonic/electronic conductivity of dion-jacobson phase niobate and tantalate layered perovskites

AU - Kobayashi, Yoji

AU - Schottenfeld, Joshua A.

AU - Macdonald, Digby D.

AU - Mallouk, Thomas E.

PY - 2007/2/22

Y1 - 2007/2/22

N2 - The layered Dion-Jacobson phase perovskites HLaTa2O 7·xH2O, HLaNb2O7·0. 5H2O and structural variants of HLaNb2O 7·0.5H2O were prepared and their AC and DC conductivities were measured as a function of temperature and atmosphere. The layered structure in HLaNb2O7·0.5H2O was modified by pillaring, exfoliation-restacking, and further annealing. Exfoliation followed by restacking markedly increased the ionic conductivity, either by creation of mesopores for hydration or by enhanced contact between layers, but pillaring had little effect. HLaNb2O7· 0.5H2O was prone to reduction under hydrogen, yielding a mixed ionic-electronic conductor. In-plane conductivity measurements of an oriented film of HLaNb2O7·0.5H2O showed enhanced ionic conductivity attributed to the anisotropic conductivity of the sheets, but reduction under a hydrogen atmosphere was apparent. The reduction could be suppressed by adding water vapor to the ambient atmosphere or by replacing the B-site niobium with tantalum, which is less easily reduced.

AB - The layered Dion-Jacobson phase perovskites HLaTa2O 7·xH2O, HLaNb2O7·0. 5H2O and structural variants of HLaNb2O 7·0.5H2O were prepared and their AC and DC conductivities were measured as a function of temperature and atmosphere. The layered structure in HLaNb2O7·0.5H2O was modified by pillaring, exfoliation-restacking, and further annealing. Exfoliation followed by restacking markedly increased the ionic conductivity, either by creation of mesopores for hydration or by enhanced contact between layers, but pillaring had little effect. HLaNb2O7· 0.5H2O was prone to reduction under hydrogen, yielding a mixed ionic-electronic conductor. In-plane conductivity measurements of an oriented film of HLaNb2O7·0.5H2O showed enhanced ionic conductivity attributed to the anisotropic conductivity of the sheets, but reduction under a hydrogen atmosphere was apparent. The reduction could be suppressed by adding water vapor to the ambient atmosphere or by replacing the B-site niobium with tantalum, which is less easily reduced.

UR - http://www.scopus.com/inward/record.url?scp=33847741770&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33847741770&partnerID=8YFLogxK

U2 - 10.1021/jp063061d

DO - 10.1021/jp063061d

M3 - Article

AN - SCOPUS:33847741770

VL - 111

SP - 3185

EP - 3191

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 7

ER -