Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Novel BaZr0.1Ce0.7Y0.2O3-δ (BZCYO)-Ce0.8Y0.2O2-δ (YDC) composite ceramic electrolyte for low-temperature SOFCs
KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Ceramics.
KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Ceramics.
KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Ceramics.ORCID iD: 0000-0003-3060-9987
Show others and affiliations
(English)Article in journal (Other academic) Submitted
Abstract [en]

Novel BaZr0.1Ce0.7Y0.2O3-δ (BZCYO)-Ce0.8Y0.2O2-δ (YDC) composite ceramic electrolyte possessing both proton and oxygen ion vacancies conduction was first reported. There are no chemical reactions between the two compositions. The composite ceramic electrolyte shows excellent chemical stability to reduction. BZCYO2-YDC8 exhibits the highest bulk ionic conductivities in the temperature range of 450 oC to 650 oC and total ionic conductivities when the temperatures are higher than 550 oC. The conductivity enhancement mechanism has been discussed. BZCYO-YDC composite ceramics may be promising electrolytes in low-temperature solid oxide fuel cells.a)

National Category
Materials Engineering
Identifiers
URN: urn:nbn:se:kth:diva-51495OAI: oai:DiVA.org:kth-51495DiVA: diva2:464287
Note
QS 2011 QS 20120326Available from: 2011-12-13 Created: 2011-12-13 Last updated: 2012-03-26Bibliographically approved
In thesis
1. Advanced Functional Materials for Intermediate-Temperature Ceramic Fuel Cells
Open this publication in new window or tab >>Advanced Functional Materials for Intermediate-Temperature Ceramic Fuel Cells
2011 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Low to intermediate-temperature solid oxide fuel cell (SOFC, 500 oC-700 oC) based on doped ceria (DCO) electrolyte has attracted much attention during the last decade. However, DCO suffers from electronic conduction caused byreduction of Ce (IV) to Ce (III) at high temperatures and low oxygen partial pressures and has a high grain-boundary resistivity. Co-doping has been chosen as the focus of this PhD study to investigate the feasibility of overcoming these technical problems.

For different purposes, two co-doping strategies have been implemented to improve the properties of the singly doped ceria. Sr addition has been used with the aim of enhancing the ionic conductivity of Ce0.8Sm0.2O2-δ. The Sr addition greatly improves the microstructure of the space charge layers and the space charge potentials. The total conductivity of Sm and Sr co-doped ceria is higher than that of Ce0.8Sm0.2O1.9, and Ce0.8(Sm0.7Sr0.3)0.2O2-δ has the highest total conductivity. Sm and Lu co-doped ceria with composition of Ce1-x(Sm3Lu2)x/5O2-δ was investigated to validate the concept of critical dopant ionic radius. The elastic strain and critical dopant ionic radius may have an immediate effect on the grain bulk ionic conduction characteristics.

As the basis of the ceramic electrolyte processing, the effect of the powder synthesis routes, including Polyvinyl alcohol (PVA)-assisted sol-gel process,Polyethylene glycol (PEG)-assisted sol-gel process, citrate sol-gel process and oxalate co-precipitation process (OCP), on the microstructure and the ionic conductivity of the Ce0.85Sm0.075Nd0.075O2-δ (SNDC) electrolyte has beeninvestigated. OCP process results in higher relative density and ionic conductivity, lower grain-boundary resistance and activation energy.

Sm0.5Sr0.5CoO3-δ (SSC) cathode was investigated for SOFCs based on Ce0.85Sm0.075Nd0.075O2-δ (SNDC) electrolyte. Kinetics of oxygen reduction reaction (ORR) on porous SSC cathode was investigated by AC impedance spectra. Finally, novel BaZr0.1Ce0.7Y0.2O3-δ (BZCYO)-Ce0.8Y0.2O2-δ (YDC) composite ceramic electrolyte having both proton and oxygen ion conduction was studied. The composite ceramic electrolyte shows an enhanced ionic conductivity and chemical stability against reduction.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2011. vii, 49 p.
National Category
Ceramics
Identifiers
urn:nbn:se:kth:diva-51479 (URN)978-91-7501-145-5 (ISBN)
Public defence
2011-12-19, F3, KTH, Lindstedtsvägen 26, Stockholm, 10:00 (English)
Opponent
Supervisors
Note
QC 20111213Available from: 2011-12-13 Created: 2011-12-12 Last updated: 2011-12-13Bibliographically approved

Open Access in DiVA

No full text

Authority records BETA

Zhao, Zhe

Search in DiVA

By author/editor
Gao, ZhanBergman, BillZhao, Zhe
By organisation
Ceramics
Materials Engineering

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 66 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf