BSCF Cathode Research Articles

Successful preparation of BaCo 0.5Fe 0.5O 3– δ cathode oxide by rapidly cooling allowing for high-performance proton-conducting solid oxide fuel cells

A pure phase BaCo_0.5Fe_0.5O_{3–<i>δ</i>} (BCF), which cannot be obtained before, is successfully prepared in this study by using the calcination method with a rapid cooling procedure. The successful preparation of BCF allows the evaluation of this material as a cathode for proton-conducting solid oxide fuel cells (H-SOFCs) for the first time. An H-SOFC using the BCF cathode achieves an encouraging fuel cell performance of 2012 mW·cm^–2 at 700 ℃, two-fold higher than that of a similar cell using the classical high-performance Ba_0.5Sr_0.5Co_0.8Fe_0.2O_{3–<i>δ</i>} (BSCF) cathode. First-principles calculations reveal the mechanism for the performance enhancement, indicating that the new BCF cathode significantly lowers the energy barriers in the oxygen reduction reaction (ORR) compared with the BSCF cathode. Therefore, improved cathode performance and fuel cell output are obtained for the BCF cell. The fuel cell using the BCF cathode also shows excellent long-term stability that can work stably for nearly 900 h without noticeable degradations. The fuel cell performance and long-term stability of the current BCF cell are superior to most of the H-SOFCs reported in previous reports, suggesting that BCF is a promising cathode for H-SOFCs.

Doped BSCF cathode materials for low-temperature solid oxide fuel cell applications-A short review

Fuel cell is used to produce electric energy through electrochemical process by energy conversion from chemical to electrical. Unlike conventional fuel combustion, fuel cell technology does not involve combustion process and completely eliminates the issues resulted from combustion emissions. Solid oxide fuel cell (SOFC) contains electrolytes which conduct oxide-ions. Higher efficiency, economically lower material cost and lower sensitivity against the impurities are the benefits with SOFC. Low-temperature (LT) or intermediate temperature SOFC is attractive because of its low value of working temperature (500–800 °C). Reducing the degradation of component, improvement of cell durability and less cost are the significant advantages with LT-SOFC. In the electrochemical reduction in LT-SOFC, cathode material plays an important role. BSCF cathode that contains Ba, Sr, Co and Fe as the important elements is widely used in LT-SOFC development due to its attractive performance. This article presents a brief review on various elements doped BSCF cathode materials and their performance. The importance of these elements on BSCF cathode properties is discussed and summarized.

Gluing Ba0.5Sr0.5Co0.8Fe0.2O3−δ with Co3O4 as a cathode for proton-conducting solid oxide fuel cells

The Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) + Co3O4 composite material is evaluated as a cathode for proton-conducting solid oxide fuel cells (H-SOFCs), which provides a new strategy to solve the thermal mismatch problem between the cathode and electrolyte without impairing the cathode performance. BSCF is a well-known cathode material for intermediate-temperature SOFCs, but its performance for H-SOFCs is unsatisfactory. One reason for the relatively low performance is the poor contact between the BSCF cathode and the electrolyte due to the high thermal expansion of BSCF. The relatively low melting point of Co3O4 is taken in this study as an advantage to bond the BSCF cathode to the electrolyte, mitigating the poor contact problem for the BSCF with the electrolyte. Furthermore, the addition of Co3O4 promotes the catalytic activity of the BSCF cathode as demonstrated by experimental studies and first-principles calculations, leading to an impressively high performance of BSCF-based cathodes for H-SOFCs.

Manufacturing method of BSCF cathode for low-temperature solid oxide fuel cell-A review

The fuel cell is a device used to convert chemical energy to electrical energy through the electrochemical process. It does not involve any intermediate step of direct combustion and gives higher conversion efficiency when compared to a conventional system. Solid oxide fuel cell is a type of fuel cell which involves oxide-ion conducting electrolytes. It has several advantages in higher efficiency, lower sensitivity to fuel impurities, and inexpensive materials. Nowadays, Low-Temperature Solid Oxide (LT-SOFC) Fuel Cell is attracted due to its lower operating temperature range of 500–800 °C. The various advantages of LT-SOFC are reducing the degradation of components involved, cell durability improvement, and reducing the cost involved. In solid oxide fuel cells, cathode plays an essential role in the electrochemical reduction. Common cathode materials are yttria-stabilized zirconia, scandia-stabilized zirconia, Samaria-doped ceria (SDC), gadolinia-doped ceria (GDC), and lanthanum strontium gallium magnesium oxide (LSGM). These cathodes have a high value of ionic conductivity at low temperatures. Recently, BSCF type cathode is attempted by researchers due to its attractive performance in LT-SOFC. The main objective of this article reviews the manufacturing method of BSCF cathode and its fabrication route on LTSO fuel cells. The result of this review article is observed to acquire knowledge of various manufacturing method of BSCF cathode in LT-SOFC fuel cell.

High performance tubular protonic ceramic fuel cells via highly-scalable extrusion process

We report an effective method to fabricate long, anode-supported tubular protonic ceramic fuel cells (PCFCs) and test cells in single-cell and short-stack mode. Further, we use our tubular PCFC platform to directly compare three high performance cathodes reported in literature: BaCo0·4Fe0·4Zr0·1Y0·1O3-δ (BCFZY), Ba0·5Sr0·5Co0·8Fe0·2O3-δ (BSCF), and PrBa0.5Sr0·5Co1·5Fe0·5O6-δ (PBSCF) using indentical preparation methods, which can minimize effects from variation of materials either due to suppliers or subsequent processing and testing from different research labs. Using a BCFZY cathode, the maximum power density of our tubular PCFC reaches 164, 308, and 517 mW cm−2 at 500, 550, and 600 °C, respectively. A 2-cell tubular short stack provides a total power of 2.3 W at 600 °C with tube diameters of 0.82 cm and a total tube active length of 3.2 cm. At 600 °C, the maximum power density reaches, 534, 517, and 326 mw cm−2 for the BSCF, BCFZY, and PBSCF cathodes, respectively. Under the same conditions, the BSCF-based cell shows the lowest total resistance mostly due to the lowest ohmic resistance and modest polarization resistance. The BCFZY-based cell has the lowest polarization resistance but larger ohmic resistance leading to a slightly higher total resistance than BSCF. The PBSCF cell has an ohmic resistance close to BSCF but a total polarization resistance much larger than either BSCF or BCFZY cell which results in the lowest overall performance.

Near Surface Studies on the Role of Graphene Oxide in the Carbon Species Activities in IT-SOFC Cathode Materials

Active roles of carbon species in solid oxide fuel cell (SOFC) cathode was simulated by adding graphene oxide (GO) into Ba0.5Sr0.5Co0.2Fe0.8 (BSCF) materials prepared by sol-gel method. The mixture was heated up to intermediate temperature SOFC range (650 - 850°C) for a period of 5 hours. A depth-profiling measurement by x-ray photoelectron spectroscopy (XPS) technique was carried out to analyse the carbon species activities at near surface of BSCF cathode. A depth-profiling analysis indicated that the graphene oxide bond components are retained under the cathode surface and does not affected the formation of carbonate phases in BSCF cathode.

Ni- and Cu-doping effects on formation and migration energies of oxygen vacancies in Ba0.5Sr0.5Fe1−x (Cu/Ni) xO3−δ perovskites: a DFT + U study

The bulk oxygen vacancy formation, migration energy and surface migration energy of BSFCu and BSFNi are calculated in this article. Two important factors affecting the formation and migration energies: the vacancy concentration and Cu/Ni doping are studied. With Cu/Ni doping, the oxygen vacancy formation energy decreases [Evac (BSF \(>\) BSCF \(>\) BSFNi \(>\) BSFCu)]. The activation energies of BSFNi and BSFCu are lower than those of BSF and BSCF cathodes. Therefore, Cu/Ni-doped BSF shows the enhancement of electrochemical activity. We also calculated the surface migration energies of (011) Ba0.5Sr0.5Fe0.75Cu.0.25O3−δ for δ = 0.125, 0.25 and (001) Ba0.5Sr0.5Fe0.75(Cu/Ni)0.25O3−δ for δ = 0.125, which for (011) BSFCu are higher than the bulk value but for (001) BSFCu and BSFNi are lower than the bulk value due to geometry considerations.

First principles study on the oxygen reduction reaction of the La1–xSrxMnO3–δ coated Ba1–xSrxCo1–yFeyO3–δ cathode for solid oxide fuel cells

A core-shell structured composite cathode for solid oxide fuel cell with Ba1–xSrxCo1–yFeyO3–δ (BSCF) as core while La1–xSrxMnO3–δ (LSM) as shell (LSM@BSCF) has been designed to achieve dual optimization of high stability and electrochemical activity. The atomic structure, oxygen vacancy formation, oxygen adsorption and diffusion, and CO2 adsorption properties of the core-shell interface have been studied by the first principles method. The calculated binding energies and interface energies suggest that the combination of La/Sr–O plane of LSM (100) surface and the Co/Fe–O plane of BSCF (100) surface is the most favourable composite structure. The formation energy of oxygen vacancy in LSM is 1.73 eV, and 0.06 eV in BSCF, thus the oxygen vacancy is easier to be formed in BSCF, which results in better oxygen ion conductivity of BSCF than LSM. The oxygen diffusion barrier from LSM to BSCF at the interface is determined to be 0.66 eV, indicating an easy oxygen ionic transport between the interface. CO2 is hard to be adsorbed onto the LSM@BSCF surface. Thus, the introducing of LSM Shell can prevent the BSCF cathode from being poisoned by CO2.

Distribution of Relaxation Times and Equivalent Circuits Analysis of Ba0.5Sr0.5Co0.8Fe0.2O3−δ

The phenomena taking place in Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) as cathodic material in solid oxide fuel cells are investigated by electrochemical impedance spectroscopy. BSCF powders are prepared by solution combustion synthesis. Measurements are collected at different temperatures, under various bias potentials and also recorded after long-term operation. Impedance spectra are thoroughly analyzed by the distribution of relaxation times (DRT) approach and compared to the standard equivalent circuits method. At 700 °C, losses are dominated by ionic conduction and charge transfer at the electrode/electrolyte interface, while oxygen adsorption and bulk diffusion provide a minor contribution to polarization. The performances of pristine materials are remarkable as a very low polarization resistance is measured at 700 °C. After prolonged testing at operative temperature, the BSCF cathodes show increasing total polarization resistance, especially due to progressive limitations in the migration of oxygen ions, caused by secondary phase formation. DRT analysis supports the physical interpretation of phenomena taking place in the material and shows the formation of a new contribution at low frequency which can be ascribed to partial decomposition of BSCF.

Chemical compatibility study of BSCF cathode materials with proton-conducting BCY/BCZY/BZY electrolytes

Ba0.5Sr0.5Co1−xFexO3−δ (BSCF) is a well-recognized cathode material for IT-SOFC. In this work, Ba0.5Sr0.5Co1−xFexO3−δ (BSCF) where x = 0.2, 0.4, 0.6, 0.8 compositions were synthesized by gel-combustion method using glycine as a fuel. Powder X-ray diffraction confirms the formation of single phase for all the compositions. As we are looking for the application of BSCF cathode for proton-conducting SOFCs, compatibility studies were made with BaCe0.8Y0.2O3−δ (BCY), BaCe0.4Zr0.4Y0.2O3−δ (BCZY) and BaZr0.8Y0.2O3−δ (BZY) electrolytes which are known to have good proton-conducting properties at elevated temperatures. Ba0.5Sr0.5Co0.4Fe0.6O3−δ (BSC4F6) and Ba0.5Sr0.5Co0.2Fe0.8O3−δ (BSC2F8) compositions showed good chemical compatibility with selected electrolyte materials at cell fabrication as well as cell operating temperature making them an appropriate cathode material. Electrical property of all the BSCF compositions was measured in air up to 1073 K by four-probe dc technique. The results showed very little effect of Fe substitution on electrical properties.

A Stable and Efficient Cathode for Fluorine-Containing Proton-Conducting Solid Oxide Fuel Cells.

Substitution of anions such as F- and Cl- can effectively improve the stability of proton-conducting electrolytes at no expense to proton conduction. However, during operation, F- and Cl- in electrolytes can transfer to the cathodes, which reduces the stability of the electrolytes. In this work, F- -doped Ba0.5 Sr0.5 Co0.8 Fe0.2 O3-δ [Ba0.5 Sr0.5 Co0.8 Fe0.2 O2.9-δ F0.1 (F-BSCF)] was prepared as a potential cathode for proton-conducting solid oxide fuel cells with BaCe0.8 Sm0.2 F0.1 O2.85 electrolyte. The incorporation of F- in the cathode depressed F- diffusion from the electrolyte and improved the stability of button cells. Temperature-changing X-ray photoelectron spectroscopy and electronic conductivity relaxation results demonstrated that the incorporation of F- enhanced the oxygen incorporation kinetics at intermediate temperatures and improved the cathode catalytic performance. Moreover, a button cell prepared with this novel cathode was stable for 270 h at a current density of 300 mA cm-2 and 700 °C, which was much superior than those containing a BSCF cathode.

Comparison of Different Perovskite Cathodes in Solid Oxide Fuel Cells

AbstractThis study compares the electrochemical performance of three perovskite cathode materials, La0.6Sr0.4Co0.2Fe0.8O3 (LSCF), Ba0.5Sr0.5Co0.2Fe0.8O3 (BSCF), and Sm0.5Sr0.5Co0.2Fe0.8O3 (SSCF), at different operating temperatures, in order to provide optimal operating condition and performance for different solid oxide fuel cells. Among these three cathodes, BSCF has the highest power density of 39 mW cm−2 at 600 °C, 88 mW cm−2 at 650 °C, and 168 mW cm−2 at 700 °C; LSCF has the highest power density of 263 mW cm−2 at 750 °C and 456 mW cm−2 at 800 °C. The cathode overpotentials have the same trend as the power densities. Activation energies for the total cathode area specific resistance (ASR) are calculated to be 0.44 eV, 0.38 eV, and 0.52 eV for the LSCF, BSCF, and SSCF cathodes, respectively. Stability testing of 100 h shows that the open circuit voltages of the LSCF and BSCF cathodes drop 16.1% and 22.9% at 800 °C, respectively, as well as 15.3% and 11.3% at 600 °C, respectively, indicating that the LSCF cathode is more stable at 800 °C while the BSCF cathode is more stable at 600 °C. This work should provide important guidance for the solid oxide fuel cell designs and properties.

Development of Nano-Structured and Nano-Porous BSCF Cathode for Low Temperature Solid Oxide Fuel Cell Application

ABSTRACTNano-structured and nano-porous mixed ionic and electronic conducting Ba0.5Sr0.5Co0.8Fe0.2O3–δ (BSCF) cathodes with an average grain size ∼500 nm and porosity ≤30% were processed from sol-gel method using metal organic precursors and calcined at 950°C for 5 h followed by sintering at 1000°C for 3 h. Crystallization of the powder was analyzed by X-ray diffraction and found to be dependent on calcination temperature. The calcined powder was compacted into circular discs and sintered between 1000° and 1100°C to achieve the desired porosity. Scanning electron microscopy showed porous BSCF structure, facilitating gas transfer and maximizing the number of active sites for oxygen reduction reaction at the cathode of a solid oxide fuel cell. BSCF powder was made into paste and screen printed on Ce0.8Gd0.2O2–δ (GDC) electrolyte to form a symmetric cell. Thickness of the BSCF cathode film is around 4 µm. Area specific polarization resistance was measured in a broad range of temperature (300°-700°C) at the frequency range from 10 MHz to 0.1 Hz. Impedance measurements show that area-specific resistance for the symmetric cell with BSCF cathode is 1.74 Ω-cm2 at 600°C. These results are impressive and demonstrate the potential of BSCF to be used as cathode material in new-generation SOFCs with GDC as the electrolyte.

Performance variability of Ba0.5Sr0.5Co0.8Fe0.2O3−δ cathode on proton-conducting electrolyte SOFCs with Ag and Au current collectors

Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) is one of the most active cathode materials and shows significant hydration effect suggesting possible proton conductivity. In this study, the performance of BSCF cathode on a proton-conducting BaZr0.1Ce0.7Y0.2O3−δ (BZCY) electrolyte with silver and gold current collectors was determined. The electrochemical characteristics of the symmetrical and anode-supported cell with diluted silver electrode, silver current collector or gold current collector on BSCF electrode were compared. The significant result is that, although the diluted silver electrode itself shows poor operation stability, the silver current collector has strong electrocatalytic contribution to the BSCF cathode performance on the proton-conducting electrolyte, leading to higher cell performance than that with the gold current collector.

Study on the ORR Mechanism and CO2-Poisoning Resistance of La0.8Sr0.2MnO3-δ-coated Ba0.5Sr0.5Co0.8Fe0.2O3-δ Cathode for Intermediate Temperature Solid Oxide Fuel Cells

The LSM-coated BSCF cathode with 3D core-shell architecture had been fabricated by the solution impregnation technology and presented the excellent CO2-poisoning resistance at the operating temperature. The LSM shell limited the combination of CO2 and BSCF, making that the 3D core-shell cathode present the great CO2-poisoning resistance. The three-electrode measurement was carried out to investigate the ORR mechanism. As the intervention of LSM shell, the LSM-coated BSCF presented the different ORR rate-determining step comparing with the BSCF cathode. The formation of lattice oxygen was the rate-determining step for the LSM-coated BSCF cathode, while molecular oxygen surface adsorption for the BSCF cathode. In addition, the electrochemical stability was promoted greatly with the protection of LSM shell. The LSM-coated BSCF cathode could get the stable state at about 11 h under cathodic current passage of 400 mAcm-2 at 650 °C, while it was about 70 h for the BSCF cathode. The excellent electrochemical performance and CO2-poisoning resistance made that the LSM-coated BSCF cathode appears to be a promising cathode for IT-SOFCs.

Study on the ORR Mechanism and CO2-Poisoning Resistance of La0.8Sr0.2MnO3-δ-coated Ba0.5Sr0.5Co0.8Fe0.2O3-δ Cathode for Intermediate Temperature Solid Oxide Fuel Cells

The LSM-coated BSCF cathode with 3D core-shell architecture has been fabricated by the solution impregnation technology. On the basis of previous research, the synthetic process is improved in order to promote the perovskite degree of BSCF. In this paper, the ORR mechanism of LSM-coated BSCF is studied detailedly. As the intervention of LSM shell, the LSM-coated BSCF presents the different ORR rate-determining step compared with the BSCF cathode. The formation of lattice oxygen is the rate-determining step for the LSM-coated BSCF cathode, while the molecular oxygen surface adsorption for the BSCF cathode. In the single cells test, the LSM-coated BSCF cell shows higher maximum power density than the uncoated cell. The remarkable CO2-poisoning resistant performance of LSM-coated BSCF is verified by the CO2-TPD test and the single cell potentiostatic test. The excellent electrochemical performance and CO2-poisoning resistance indicate that LSM-coated BSCF cathode appears to be a promising cathode for IT-SOFCs.

Pulsed laser deposition of Ba0.5Sr0.5Co0.8Fe0.2O3 − δ thin film cathodes for low temperature solid oxide fuel cells

Nanostructured Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) thin films were fabricated by pulsed laser deposition (PLD) as a cathode for low-temperature solid oxide fuel cells operated below 500°C. The nanoscale features in BSCF cathode was obtained by controlling the deposition parameters of PLD including oxygen pressure and substrate temperature. Compared to dense BSCF thin film cathodes, the higher surface area density of surface-roughened BSCF improved the surface reactions of the cathode with ambient oxygen, and therefore effectively improved the cathode performance. Free-standing micro-solid oxide fuel cells with nanostructured BSCF cathode showed a higher peak power density of 55mWcm−2 at 450°C as compared to those using dense BSCF thin film cathode

Enhancement in Chemical Stability of Proton Conducting Solid Oxide Electrolysis Cell (SOECs)

Developments of fuel cell technology are a great achievement for researcher’s to fulfill the need of clean and renewable energy. Among the various type of fuel cells, high temperature ceramic fuel cells inherit several advantages such as high efficiency, fuel flexibility and no precious-metal catalyst [1], but the solid oxide fuel cell (SOFC) typically uses yttria-stabilized zirconia (YSZ) at operating temperature of 800-1000°C, resulting in high cost, cell degradation and material compatibility issues. Many researchers investigated protonic ceramic conducting fuel cells (PCFCs) and have presented their possibility as intermediate temperature ceramic fuel cells [2, 3]. Proton-conducting oxides due to high conductivity with lower activation energy (0.3-0.6eV) can be operated at lower temperature of 400-600°C, which increases the cell life-time and reduces the fabrication cost. Compared with SOFCs when operating on hydrocarbon fuel, particularly CH4 conversion rate is high due to direct conversion of proton (hydrogen). A few studies try to use solid oxide electrolysis cell (SOEC) to produce hydrogen by electrolyzing steam at the IT range. [4]. In conventional oxygen-ion SOECs, steam is fed into the fuel electrode side, then the oxygen-ions move toward the air electrode, while the hydrogen is produced at fuel electrode side. One of the technical issues in SOECs is the oxidation of Ni based electrode in steam conditions, resulting in cell degradation. In proton-conducting SOECs, steam is fed at air electrode and hydrogen is produced at fuel electrode. In IT-SOFCs, the BSCF cathode is considered to be as an excellent material [5], but it can be degraded and decompose in high humid air condition. Hence, we should develop durable materials against high water vapor pressure. In this study we design the electrode material to develop highly durable cathode materials for SOECs. Moreover, in order to investigate the practical use of these cell, the accelerating durability test is designed and carried out. The durability test is conducted by periodically repeated both in fuel cell and electrolysis modes. To find the degradation analysis of the cell, micro-structural analysis is performed with SEM, TEM and XRD [6, 7], the impedance spectra and over-potential analysis are performed. E. D. Wachsman, and K. T. Lee, Science , 334, 935 (2011).C. Duan, J. Tong, M. Shang, S. Nikodemski, M. Sanders, S. Ricote, A. Almansoori and R. O’Hayre, Science, 349, 6254 (2015).L. Bi, S. Boulfrad and E. Traversa, J. Chem. Soc. Rev., 43, 8255 (2014).M. Ni, M. K. H. Leung and D. Y.C. Leung, Int. Ass. Hydrogen Eng., 33, 4040 (2008).P. K. Lohsoontorn, D. J. L. Brett, N. Laosiripojana, Y. M. Kim, J-M. Bae, Int. J. Hydrogen energy, 35, 3958 (2010).G. Kim, N. Lee, K. -B. Kim, B. -K. Kim, H. Chang, S. J. Song, J. -Y. Park, Int. J. Hydrogen energy, 38, 1571 (2013).H. Xiao, T. L. Reitz, M. A. Rottmayer, J. Power sources, 183, 49 (2008). * Corresponding authors: jyoung@sejong.ac.kr (J.-Y. Park)

Promoted CO2-poisoning resistance of La0.8Sr0.2MnO3−δ-coated Ba0.5Sr0.5Co0.8Fe0.2O3−δ cathode for intermediate temperature solid oxide fuel cells

The solution impregnation technology was used to prepare a novel core-shell structure cathode for intermediate temperature solid oxide fuel cells (IT-SOFCs). The core was composed of porous Ba0.5Sr0.5Co0.8Fe0.2O3−δ (BSCF) backbone with high oxygen conductivity, while the dense shell consisted of La0.8Sr0.2MnO3−δ (LSM) high catalytic activity and the excellent CO2-poisoning resistance. The presence of the dense LSM shell prevented the BSCF cathode from being poisoned by CO2, and improved its electrochemical performance. The best performance was achieved when the BSCF cathode was impregnated twice in the LSM precursor solution and coated by LSM shell.

Perovskite-type La0.6Sr0.4Co0.2Fe0.8O3, Ba0.5Sr0.5Co0.2Fe0.8O3, and Sm0.5Sr0.5Co0.2Fe0.8O3 cathode materials and their chromium poisoning for solid oxide fuel cells

In the pursuit for solid oxide fuel cell (SOFC) cathode materials that can operate over a wide temperature range, especially at low temperatures such as 600°C, perovskite structure materials La0.6Sr0.4Co0.2Fe0.8O3 (LSCF), Ba0.5Sr0.5Co0.2Fe0.8O3 (BSCF), and Sm0.5Sr0.5Co0.2Fe0.8O3 (SSCF) are studied. Their electrochemical performance is compared by electrochemical impedance spectroscopy (EIS) at 600°C, 700°C and 800°C for 100hrs through an AISI 441 interconnect/cathode/yttria-stabilized zirconia (YSZ) electrolyte half-cell structure. The BSCF cathode has the smallest polarization resistance at 600°C, closely followed by the SSCF cathode; the LSCF cathode has the smallest polarization resistance working at 700°C; the SSCF cathode has the smallest polarization resistance working at 800°C, closely followed by the LSCF cathode. From 600–800°C, SrCrO4 phase forms on the SSCF cathodes near the interconnect while BaCrO4 phase forms on the BSCF cathodes near the interconnect. For the LSCF cathodes, however, SrCrO4 phase is only detected at 700°C and 800°C. Cr species diffusion to and poisoning of the cathodes do not directly correlate with the half-cell performance. Lattice constant, stoichiometry, particle size, Cr deposition, and working temperature are important factors to consider.