Ion-conducting, sub-100 nm-thick film of amorphous hafnium silicate

Yoshitak Aoki, Hiroki Habazaki, Toyoki Kunitake

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

Ceramic electrolytes operating in the temperature range of 200 to 500 °C under dry atmosphere are a key material for the next-generation fuel cell and related applications. We discovered that nanometer-thick films of amorphous hafnium silicate (HfnSi1 - nOx) exhibited efficient ionic conduction at 100-400 °C in dry air. When the fraction of hafnium doping was around 0.1, the nanofilm showed a low area-specific-resistance (< 0.15 Ω cm2) at around 350 °C that was small enough for the practical fuel cell application. The sub-100 nm-thick membranes of Hf0.13Si0.87Ox, could be fabricated on porous Pt/alumina substrate to provide gas concentration cells. The electromotive force observed with H2 concentration cell indicated that the ceramic nanomembrane acted as predominant proton conductor without permeation of H2 gas. In addition, the Hf0.13Si0.87Ox and Zr0.11Si0.89Ox membranes responded to the change of O2 pressures in O2 concentration cells, while the Al0.16Si0.84Ox and Ce0.06Si0.94Ox membranes did not produce the electrical voltage by gradient of O2 pressure. We conclude that Hf0.13Si0.87Ox nanomembrane is promising as electrolyte material for fuel cells and related ionics devices.

Original languageEnglish
Pages (from-to)115-121
Number of pages7
JournalSolid State Ionics
Volume181
Issue number3-4
DOIs
Publication statusPublished - Feb 24 2010
Externally publishedYes

Fingerprint

Hafnium
Silicates
hafnium
Thick films
fuel cells
thick films
Fuel cells
silicates
Ions
membranes
Membranes
conduction
Electrolytes
Gases
cells
electrolytes
ceramics
Ionic conduction
ions
Electromotive force

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics

Cite this

Ion-conducting, sub-100 nm-thick film of amorphous hafnium silicate. / Aoki, Yoshitak; Habazaki, Hiroki; Kunitake, Toyoki.

In: Solid State Ionics, Vol. 181, No. 3-4, 24.02.2010, p. 115-121.

Research output: Contribution to journalArticle

Aoki, Yoshitak ; Habazaki, Hiroki ; Kunitake, Toyoki. / Ion-conducting, sub-100 nm-thick film of amorphous hafnium silicate. In: Solid State Ionics. 2010 ; Vol. 181, No. 3-4. pp. 115-121.
@article{e23126e375cf45f29ddf599f3aae1ac1,
title = "Ion-conducting, sub-100 nm-thick film of amorphous hafnium silicate",
abstract = "Ceramic electrolytes operating in the temperature range of 200 to 500 °C under dry atmosphere are a key material for the next-generation fuel cell and related applications. We discovered that nanometer-thick films of amorphous hafnium silicate (HfnSi1 - nOx) exhibited efficient ionic conduction at 100-400 °C in dry air. When the fraction of hafnium doping was around 0.1, the nanofilm showed a low area-specific-resistance (< 0.15 Ω cm2) at around 350 °C that was small enough for the practical fuel cell application. The sub-100 nm-thick membranes of Hf0.13Si0.87Ox, could be fabricated on porous Pt/alumina substrate to provide gas concentration cells. The electromotive force observed with H2 concentration cell indicated that the ceramic nanomembrane acted as predominant proton conductor without permeation of H2 gas. In addition, the Hf0.13Si0.87Ox and Zr0.11Si0.89Ox membranes responded to the change of O2 pressures in O2 concentration cells, while the Al0.16Si0.84Ox and Ce0.06Si0.94Ox membranes did not produce the electrical voltage by gradient of O2 pressure. We conclude that Hf0.13Si0.87Ox nanomembrane is promising as electrolyte material for fuel cells and related ionics devices.",
author = "Yoshitak Aoki and Hiroki Habazaki and Toyoki Kunitake",
year = "2010",
month = "2",
day = "24",
doi = "10.1016/j.ssi.2009.02.016",
language = "English",
volume = "181",
pages = "115--121",
journal = "Solid State Ionics",
issn = "0167-2738",
publisher = "Elsevier",
number = "3-4",

}

TY - JOUR

T1 - Ion-conducting, sub-100 nm-thick film of amorphous hafnium silicate

AU - Aoki, Yoshitak

AU - Habazaki, Hiroki

AU - Kunitake, Toyoki

PY - 2010/2/24

Y1 - 2010/2/24

N2 - Ceramic electrolytes operating in the temperature range of 200 to 500 °C under dry atmosphere are a key material for the next-generation fuel cell and related applications. We discovered that nanometer-thick films of amorphous hafnium silicate (HfnSi1 - nOx) exhibited efficient ionic conduction at 100-400 °C in dry air. When the fraction of hafnium doping was around 0.1, the nanofilm showed a low area-specific-resistance (< 0.15 Ω cm2) at around 350 °C that was small enough for the practical fuel cell application. The sub-100 nm-thick membranes of Hf0.13Si0.87Ox, could be fabricated on porous Pt/alumina substrate to provide gas concentration cells. The electromotive force observed with H2 concentration cell indicated that the ceramic nanomembrane acted as predominant proton conductor without permeation of H2 gas. In addition, the Hf0.13Si0.87Ox and Zr0.11Si0.89Ox membranes responded to the change of O2 pressures in O2 concentration cells, while the Al0.16Si0.84Ox and Ce0.06Si0.94Ox membranes did not produce the electrical voltage by gradient of O2 pressure. We conclude that Hf0.13Si0.87Ox nanomembrane is promising as electrolyte material for fuel cells and related ionics devices.

AB - Ceramic electrolytes operating in the temperature range of 200 to 500 °C under dry atmosphere are a key material for the next-generation fuel cell and related applications. We discovered that nanometer-thick films of amorphous hafnium silicate (HfnSi1 - nOx) exhibited efficient ionic conduction at 100-400 °C in dry air. When the fraction of hafnium doping was around 0.1, the nanofilm showed a low area-specific-resistance (< 0.15 Ω cm2) at around 350 °C that was small enough for the practical fuel cell application. The sub-100 nm-thick membranes of Hf0.13Si0.87Ox, could be fabricated on porous Pt/alumina substrate to provide gas concentration cells. The electromotive force observed with H2 concentration cell indicated that the ceramic nanomembrane acted as predominant proton conductor without permeation of H2 gas. In addition, the Hf0.13Si0.87Ox and Zr0.11Si0.89Ox membranes responded to the change of O2 pressures in O2 concentration cells, while the Al0.16Si0.84Ox and Ce0.06Si0.94Ox membranes did not produce the electrical voltage by gradient of O2 pressure. We conclude that Hf0.13Si0.87Ox nanomembrane is promising as electrolyte material for fuel cells and related ionics devices.

UR - http://www.scopus.com/inward/record.url?scp=77649188422&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=77649188422&partnerID=8YFLogxK

U2 - 10.1016/j.ssi.2009.02.016

DO - 10.1016/j.ssi.2009.02.016

M3 - Article

AN - SCOPUS:77649188422

VL - 181

SP - 115

EP - 121

JO - Solid State Ionics

JF - Solid State Ionics

SN - 0167-2738

IS - 3-4

ER -