Electrochemical Performance of Barium Strontium Cobalt Ferrite -Samarium Doped Ceria- Argentum for Low Temperature Solid Oxide Fuel Cell

A low operating temperature is one of the concerns in commercialising solid oxide fuel cells (SOFCs) as a portable power source. The aim of this research is to develop a new cathode material, barium strontium cobalt ferrite–samarium doped ceria (BSCF-SDC) added with argentum (Ag) for low-temperature SOFCs (LT-SOFCs). The composite powder was prepared through high-energy ball milling at 550 rpm for 2 h with a BSCF:SDC powder ratio of 50:50. The composite powder was calcined at 950 °C for 2 h and then mixed with Ag (1wt%, 3wt% and 5wt%) via dry milling at 150 rpm. The phase stability of the resulting samples was examined by X-ray diffractometry, and powder particle sizes were determined by using a Zeta-Sizer Nano ZS. The thermal stability of each sample was determined on the basis of thermal expansion coefficients (TECs), and electrochemical characteristics were determined through electrochemical impedance spectroscopy to investigate the performance of BSCF-SDC-Ag in LT-SOFCs (400–600 °C). Phase analysis demonstrated no impurity phases existed. Particle size analysis revealed that increment in Ag content affect the particle size of BSCF-SDCC. TEC analysis demonstrated that BSCF-SDC-Ag1% has a mismatch value of 16.39%, which is within the acceptable TEC range of 15%–20%. BSCF-SDC-Ag1% showed a maximum conductivity of 39.37Scm-1 at 600 °C.

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Effect of unsintered gadolinium-doped ceria buffer layer on performance of metal-supported solid oxide fuel cells using unsintered barium strontium cobalt ferrite cathode

Journal of Power Sources ◽

10.1016/j.jpowsour.2010.03.095 ◽

2010 ◽

Vol 195 (19) ◽

pp. 6420-6427 ◽

Cited By ~ 38

Author(s):

Yu-Mi Kim ◽

Pattaraporn Kim-Lohsoontorn ◽

Joongmyeon Bae

Keyword(s):

Fuel Cells ◽

Solid Oxide Fuel Cells ◽

Buffer Layer ◽

Cobalt Ferrite ◽

Solid Oxide ◽

Doped Ceria ◽

Oxide Fuel ◽

Barium Strontium ◽

Gadolinium Doped Ceria

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Ba0.5Sr0.5Co0.8Fe0.2-SDC Carbonate Composite Cathode for Low-Temperature SOFCs

Materials Science Forum ◽

10.4028/www.scientific.net/msf.840.247 ◽

2016 ◽

Vol 840 ◽

pp. 247-251 ◽

Cited By ~ 5

Author(s):

Linda Agun ◽

Mohamed Hakim Ahmad Shah ◽

Sufizar Ahmad ◽

Hamimah Abd Rahman

Keyword(s):

Low Temperature ◽

Cross Section ◽

Composite Cathode ◽

High Energy ◽

Solid Oxide ◽

Doped Ceria ◽

Oxide Fuel ◽

Porous Composite ◽

Energy Ball ◽

Scanning Electron

The composite cathode Ba0.5Sr0.5Co0.8Fe0.2 (BSCF)–samarium-doped ceria carbonate (SDCc) was reviewed based on different (Li/Na)2 carbonate molarities (67:33, 62:38, and 53:47 (mol.%)). Effects of (Li/Na)2 carbonate on BSCF was studied in terms of chemical, thermal, and physical properties. Composite-cathode powders were prepared using high-energy ball milling (HEBM) and calcined at 750 °C for 2 h before uniaxial pressing to form a pellets. Afterwards, the pellets were sintered at 600 °C for 90 min to obtain porous composite-cathode pellets. Powders behaviors were examined based on particle size and thermal expansion by using Image J software, field-emission scanning electron microscopy (FESEM) and dilatometry respectively. Cross-section morphology of the pellets were characterised by FESEM to examine grain positions and by the Archimedes principle to identify the porosity, respectively. The quantitative elements for the BSCF-SDCc pellet were identified using energy-dispersive spectroscopy (EDS). HEBM enabled the cathode to achieve a nanocomposite state. Cathode cells obtained became porous when porosity values were between 26% and 30%. These results showed that BSCF–SDCc has high potential for low-temperature solid oxide fuel cell (LT-SOFC) applications.

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Effect of dopants [Gd3+, Sm3+, Ca2+, Sr2+ and Ba2+] on the performance characteristics of ceria based electrolytes for application in solid oxide fuel cells

Malaysian Journal of Fundamental and Applied Sciences ◽

10.11113/mjfas.v10n2.258 ◽

2014 ◽

Vol 10 (2) ◽

Author(s):

M.L. Reni ◽

A. Samson Nesaraj

Keyword(s):

Particle Size ◽

Fuel Cells ◽

Low Temperature ◽

Solid Oxide Fuel Cells ◽

Average Particle Size ◽

Solid Oxide ◽

Narrow Particle Size Distribution ◽

Average Particle ◽

Doped Ceria ◽

Oxide Fuel

Doped CeO2 based materials are now-a-days proposed as alternate electrolyte materials for solid oxide fuel cells (SOFCs) working at low temperature (~723 – 873 K). In this research work, nanoparticles of CeO2 doped with Gd3+, Sm3+, Ca2+, Sr2+ and Ba2+were prepared by a simple homogeneous chemical precipitation method. The prepared materials (after heat treatment at 1023 K for 2 hours) were systematically characterized by XRD, EDAX analysis, FTIR , particle size analysis and SEM. Lattice parameters were calculated from the XRD data. The XRD results indicate that all the doped ceria samples studied are single phase with a cubic fluorite structure. The average particle size of the doped ceria powder was about 48 – 115 nm and the particles have shown narrow particle size distribution patterns. AC impedance spectroscopy studies performed on the sintered specimens have shown better oxide ion conductivity values and hence these materials may be suitable for application as electrolyte materials in solid oxide fuel cells working at low temperature (~723 – 873 K). ________________________________________GRAPHICAL ABSTRACT

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Effects of Binary (Lithium/Natrium)2 Carbonates on the Phase and Microstructural Stability of Lscf-Sdc for Low Temperature Solid Oxide Fuel Cells

Sains Malaysiana ◽

10.17576/jsm-2020-4912-22 ◽

2020 ◽

Vol 49 (12) ◽

pp. 3101-3113

Author(s):

Hamimah Abd. Rahman ◽

Linda Agun ◽

Kei Hoa Ng ◽

Sufizar Ahmad ◽

Nur Azmah Nordin

Keyword(s):

Low Temperature ◽

High Energy ◽

Solid Oxide ◽

Stability Test ◽

Doped Ceria ◽

Oxide Fuel ◽

Microstructural Stability ◽

Term Stability ◽

Long Term Stability

Most studies focus on introducing of doped ceria carbonate into cathode materials to enhance the cathode ionic conductivity for low temperature solid oxide fuel cell. In this work, we aim to identify the influence of Lithium/Natrium binaries (Li/Na)2 carbonates addition on Lanthanum Strontium Carbonate Ferrite-Samarium-Doped Ceria (LSCF-SDC) composite cathode on the phase and microstructural stability under long-term durability of 1000 h. Three different binaries (Li/Na)2 carbonate of 67:33, 62:38, and 53:47 mol.% were incorporated into LSCF-SDC via high energy ball milling method. The phase and microstructural stability as a function of operating temperature (400 and 600 °C) were studied using X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM). Archimedes principle was applied to evaluate the porosity of the cathode pellets. Electrochemical impedance spectroscopy measurements were performed by using impedance setup at 600 °C under open-circuit condition. The XRD findings demonstrated that cathodes able to retain their chemical phases after stability test. Qualitative results show that the cathode morphology exhibits a slight increment on the particle size after the ageing process at 1000 h. All cathodes prepared at various binary carbonate ratio still maintain their porosity values between 26 and 32% after long-term stability test. This finding has yielded a smaller area specific resistance of 0.66 Ω.cm2 at 600 °C. Therefore, incorporating binary (Li/Na)2 carbonate in LSCF-SDC shows a good combination when insignificant changes observed after long-term stability test of 1000 h.

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