Optimisation and Evaluation of La0.6Sr0.4CoO3 – δ Cathode for Intermediate Temperature Solid Oxide Fuel Cells

In this work, La_0.6Sr_0.4CoO_{3 – δ}/Ce_{1 – x}Gd_xO_{2 – δ} (LSC/GDC) composite cathodes are investigated for SOFC application at intermediate temperatures, especially below 700 °C. The symmetrical cells are prepared by spraying LSC/GDC composite cathodes on a GDC tape, and the lowest polarisation resistance (R_p) of 0.11 Ω cm² at 700 °C is obtained for the cathode containing 30 wt.‐% GDC. For the application on YSZ electrolyte, symmetrical LSC cathodes are fabricated on a YSZ tape coated on a GDC interlayer. The impact of the sintering temperature on the microstructure and electrochemical properties is investigated. The optimum temperature is determined to be 950 °C; the corresponding R_p of 0.24 Ω cm² at 600 °C and 0.06 Ω cm² at 700 °C are achieved, respectively. An YSZ‐based anode‐supported solid oxide fuel cell is fabricated by employing LSC/GDC composite cathode sintered at 950 °C. The cell with an active electrode area of 4 × 4 cm² exhibits the maximum power density of 0.42 W cm^–2 at 650 °C and 0.54 W cm^–2 at 700 °C. More than 300 h operating at 650 °C is carried out for an estimate of performance and degradation of a single cell. Despite a decline at the beginning, the stable performance during the later term suggests a potential application.     

Performance of Cobalt‐free La0.6Sr0.4Fe0.9Ni0.1O3–δ Cathode Material for Intermediate Temperature Solid Oxide Fuel Cells

A series of cobalt‐free perovskite‐type cathode materials La_0.6Sr_0.4Fe_1–xNi_xO_3–δ (0 ≤ x ≤ 0.15) for intermediate temperature solid oxide fuel cells (IT‐SOFCs) are prepared by a citric‐nitrate process. The conductivities of the cathode materials are measured as functions of temperature (300–800 °C) in air by AC impedance method, and the La_0.6Sr_0.4Fe_0.9Ni_0.1O_3–δ (LSFN10) has the highest conductivity to be 160 S cm^–1 at 400 °C. A single IT‐SOFC based on LSFN10 cathode, BaZr_0.1Ce_0.7Y_0.2O_3–δ electrolyte membrane and Ni–BaZr_0.1Ce_0.7Y_0.2O_3–δ anode substrate was fabricated by a simple spin‐coating process, and the performances of the cell using hydrogen as fuel and air as the oxidant were researched by electrochemical methods at 600–700 °C. The maximum power densities of the cell are 405 mW cm^–2 at 700 °C, 238 mW cm^–2 at 650 °C, and 140 mW cm^–2 at 600 °C, respectively. The results indicate that the LSFN10 is a promising cathode material for proton conducting IT‐SOFCs.     

Fabrication of BaZr0.1Ce0.7Y0.2O3 – δ ‐Based Proton‐Conducting Solid Oxide Fuel Cells Co‐Fired at 1,150 °C

Dense proton‐conducting BaZr_0.1Ce_0.7Y_0.2O_{3 – δ} (BZCY) electrolyte membranes were successfully fabricated on NiO–BZCY anode substrates at a low temperature of 1,150 °C via a combined co‐press and co‐firing process. To fabricate full cells, the LaSr₃Co_1.5Fe_1.5O_{10 – δ}–BZCY composite cathode layer was fixed to the electrolyte membrane by two means of one‐step co‐firing and two‐step co‐firing, respectively. The SEM results revealed that the cathode layer bonded more closely to the electrolyte membrane via the one‐step co‐firing process. Correspondingly, determined from the electrochemical impedance spectroscopy measured under open current conditions, the electrode polarisation and Ohmic resistances of the one‐step co‐fired cell were dramatically lower than the other one for its excellent interface adhesion. With humidified hydrogen (2% H₂O) as the fuel and static air as the oxidant, the maximum power density of the one‐step co‐fired single cell achieved 328 mW cm^–2 at 700 °C, showing a much better performance than that of the two‐step co‐fired single cell, which was 264 mW cm^–2 at 700 °C.     

Electrochemical Performance of Cobalt‐free Nd0.5Ba0.5Fe1–xNixO3–δ Cathode Materials for Intermediate Temperature Solid Oxide Fuel Cells

A new series of cobalt‐free perovskite‐type oxides, Nd_0.5Ba_0.5Fe_1–xNi_xO_3–δ (0 ≤ x ≤ 0.15), have been prepared by a citric acid‐nitrate process and investigated as cathode materials for proton conducting intermediate temperature solid oxide fuel cells (IT‐SOFCs). The conductivity of the oxides was measured at 300–800 °C in air. It is discovered that partial substitution of Ni for Fe‐sites in Nd_0.5Ba_0.5Fe_1–xNi_xO_3–δ obviously enhances the conductivity of the oxides. Among the series of oxides, the Nd_0.5Ba_0.5Fe_0.9Ni_0.1O_3–δ (NBFNi10) exhibits the highest conductivity of 140 S cm⁻¹ in air at 550 °C. A single H₂/air fuel cell with proton‐conducting BaZr_0.1Ce_0.7Y_0.2O_3–δ (BZCY) electrolyte membrane (ca. 40 μm thickness) and NBFNi10‐BZCY composite cathode and NiO‐BZCY composite anode was fabricated and tested at 600–700 °C. The peak power density and the interfacial polarization resistance (R_p) of the cell are 490 mW cm⁻² and 0.15 Ω cm² at 700 °C, respectively. The experimental results indicate that NBFNi10 is a promising cathode material for the proton‐conducting IT‐SOFCs.     

Structures and electrical conductivities of Gd3+ and Fe3+ co-doped cerium oxide electrolytes sintered at low temperature for ILT-SOFCs

Gd³⁺ and Fe³⁺ co-doped cerium oxide electrolytes, Ce_0.9Gd_0.1‐xFe_xO_2-δ (x?=?0.00, 0.01, 0.03, 0.05, 0.07, 0.10), were prepared by co-precipitation for ultrafine precursor powders and sintering for densified ceramic pellets. The crystal and microscopic structures were characterized by XRD, FESEM and Raman spectroscopy and their electrical properties were studied by AC impedance spectroscopy and the measurement of single cell's outputs. In comparison with Ce_0.9Gd_0.1O_1.95, the ceramic pellets of Ce_0.9Gd_0.1‐xFe_xO_2-δ with a relative density of 95% can be obtained after sintered at 1000?°C for 5?h, showing a remarkably enhanced sintering performance with a sintering temperature reduction of 500?°C, which might be ascribed to the highly activated migration of constituent species in the cerium oxide lattice doped with Gd³⁺ and Fe³⁺ions. Moreover, the electrical conductivity of Ce_0.9Gd_0.1‐xFe_xO_2-δ can be significantly enhanced depending on the mole fraction x, with Ce_0.9Gd_0.07Fe_0.03O_1.95 exhibiting the highest electrical conductivity of 38 mS/cm at 800?°C, about 36% higher than that of Ce_0.9Gd_0.1O_1.95 electrolyte sintered at 1500?°C for 5?h. So, The Gd³⁺ and Fe³⁺ co-doped cerium oxide would be an excellent candidate electrolyte for ILT SOFCs due to its prominent sintering performance and enhanced electrical conductivity.     

Achieving 360 NL h−1 Hydrogen Production Rate Through 30‐Cell Solid Oxide Electrolysis Stack with LSCF–GDC Composite Oxygen Electrode

A 30‐cell solid oxide electrolysis (SOE) stack consisting of 30‐cell planar Ni–YSZ hydrogen electrode‐supported single cell with La_0.6Sr_0.4Co_0.2Fe_0.8O_3–δ–Ce_0.9Gd_0.1O_1.95 (LSCF–GDC) composite oxygen electrodes, interconnects, and sealing materials was tested at 750 °C in steam electrolysis mode for hydrogen production. The direction of gas flow in the stack was a cross‐flow configuration, and the stack configuration was designed to open gas flow channels at the air outlet. The electrolysis efficiency of the stack was higher than 100% at 90/10H₂O/H₂ ratio under <0.5 A cm⁻² current density. During hydrogen production, the stack was operated at 750 °C under 0.5 A cm⁻² constant current density for more than 500 h with 4.06% k h⁻¹ degradation rate. Up to 73% steam conversion rate and 91.6% current efficiency were obtained; the net hydrogen production rate reached as high as 361.4 NL h⁻¹. Our results suggested that the SOE stack that was designed with LSCF–GDC composite oxygen electrode could be used to conduct large‐scale hydrogen production.     

Sr2Fe1.5Mo0.5O6–δ – Zr0.84Y0.16O2–δ Materials as Oxygen Electrodes for Solid Oxide Electrolysis Cells

The high‐temperature solid oxide electrolysis cell (SOEC) is one of the most promising devices for hydrogen mass production. To make SOEC suitable from an economical point of view, each component of the SOEC has to be optimized. At this level, the optimization of the oxygen electrode is of particular interest since it contributes to a large extent to the cell polarization resistance. The present paper is focused on an alternative oxygen electrode of Zr_0.84Y_0.16O_2–δ‐Sr₂Fe_1.5Mo_0.5O_6–δ (YSZ‐SFM). YSZ‐SFM composite oxygen electrodes were fabricated by impregnating the YSZ matrix with SFM, and the ion‐impregnated YSZ‐SFM composite oxygen electrodes showed excellent performance. For a voltage of 1.2 V, the electrolysis current was 223 mA cm⁻², 327 mA cm⁻² and 310 mA cm⁻² at 750 °C for the YSZ‐SFM10, YSZ‐SFM20, and YSZ‐SFM30 oxygen electrode, respectively. A hydrogen production rate as high as 11.46 NL h⁻¹ has been achieved for the SOEC with the YSZ‐SFM20 electrode at 750 °C. The results demonstrate that YSZ‐SFM fabricated by impregnating the YSZ matrix with SFM is a promising composite electrode for the SOEC.     

Electrochemical Performance of PrBaCo2O5+δ and Sm0.5Sr0.5CoO3−δ Infiltrated Ce0.9Gd0.1O1.95 Cathodes

Cathodes with PrBaCo₂O_5+δ (PBC) and Sm_0.5Sr_0.5CoO_3−δ (SSC) infiltrated on Ce_0.9Gd_0.1O_1.95 (CGO) backbones are prepared using metal nitrates as precursors and ethanol as wetting agent. Electrochemical impedance spectra (EIS) are measured from cathode/CGO/cathode symmetrical cells in 400–650 °C under humidified air. The results indicate that interfacial area specific resistance (ASR) value decreases and then increases with infiltrate loading and minimum values occur at 50 wt.% loading (relative to sum of infiltrate and backbone) for both PBC and SSC infiltrates. ASR values of PBC infiltrated cathodes are lower than that of corresponding SSC infiltrated cathodes in general, and in particular ASR values as low as 1.36 × 10⁻² and 2.27 × 10⁻² Ω cm² are obtained at 650 °C in air for 50 wt.% PBC and 50 wt.% SSC infiltrated cathodes, respectively. Conductivity values of CGO electrolyte increase with infiltrate loading and agree with the reported values when the loading reaches 50 wt.%.     

Novel Metal Substrates for High Power Metal‐supported Solid Oxide Fuel Cells

Novel high permeable porous Ni‐Mo substrates with different area densities of straight gas flow channels are successfully developed to improve the hydrogen fuel gas and the water byproduct diffusion in the anode and supporting substrate. Metal‐supported cell A, cell B and cell C with 5 × 5 cm² supporting substrates are fabricated by atmospheric plasma spraying processes, these cells have the material structure of Ni‐Mo/LSCM (La_0.75Sr_0.25Cr_0.5‐Mn_0.5O_3–δ)/NiO‐LDC(Ce_0.55La_0.45O_2–δ)/SDC(Sm_0.15Ce_0.85O_3–δ)/LSGM (La_0.8Sr_0.2Ga_0.8Mg_0.2O_3–δ)/SSC(Sm_0.5Sr_0.5CoO_3–δ). Cell A is supported by a conventional porous Ni‐Mo substrate without straight gas flow channels, cell B and cell C are supported respectively by the novel high permeable porous Ni‐Mo substrates with 1.5 and 2.73 channels per square centimeter. The power densities at 0.8 V and 750 °C are 550, 998 and 1,161 mW cm⁻² for cell A, cell B and cell C respectively. The 100 h durability test at the constant current density of 400 mA cm⁻² and 650 °C shows cell B and cell C have smaller degradation rates than cell A. The results obtained from AC impedance and circuit model analyses indicate that the electrolyte ohm and the cathode polarization resistances are significantly reduced by introducing straight gas flow channels into the supporting substrate.     

A CO2‐stable hollow‐fiber membrane with high hydrogen permeation flux

A Mo‐substituted lanthanum tungstate mixed proton‐electron conductor, La_5.5W_0.6Mo_0.4O_11.25?δ (LWM04), was synthesized using solid state reactions. Dense U‐shaped LWM04 hollow‐fiber membranes were successfully prepared using wet‐spinning phase‐inversion and sintering. The stability of LWM04 in a CO₂‐containing atmosphere and the permeation of hydrogen through the LWM04 hollow‐fiber membrane were investigated in detail. A high hydrogen permeation flux of 1.36 mL/min cm² was obtained for the U‐shaped LWM04 hollow‐fiber membranes at 975°C when a mixture of 80% H₂?20% He was used as the feed gas and the sweep side was humidified. Moreover, the hydrogen permeation flux did not significantly decrease over 70 h of operation when fed with a mixture containing 25% CO₂, 50% H₂, and 25% He, indicating that the LWM04 hollow‐fiber membrane has good stability under a CO₂‐containing atmosphere. © 2015 American Institute of Chemical Engineers AIChE J, 61: 1997–2007, 2015     

A redox−reversible perovskite electrode for CeO2− and LaGaO3−based symmetric solid oxide fuel cells

Perovskite oxide SrFe_0.9Mo_0.1O_3?δ (SFM) was evaluated as the electrode for symmetric solid oxide fuel cells (S–SOFCs) with Sm_0.2Ce_0.8O_2?δ (SDC) and La_0.9Sr_0.1Ga_0.8Mg_0.2O_3?δ (LSGM) electrolytes. Under reducing conditions at 800 °C, the SFM was reduced to be a multi-phase composite consisting of the single perovskite phase, Ruddlesden–Popper (RP) layered perovskite phase, and Fe⁰ phase. After reoxidation at 800 °C in air, this multi?phase system was again transformed into the parent perovskite phase again, indicating good redox reversibility of the SFM. At 700 °C, polarisation resistances of the SFM used as the cathodes on the LSGM and SDC electrolytes were 0.28 and 0.14 Ω cm², respectively, in air. Using H₂ as a fuel, the LSGM and SDC supported S–SOFCs with the SFM symmetric electrodes showed the peak power outputs of 253 and 269 mW cm^?2, respectively, at 700 °C. Finally, the good long-term stability and redox-cycling stability of the S–SOFCs further demonstrate the potential of the SFM as the symmetric electrode.     

Performance and stability in H2S of SrFe0.75Mo0.25O3-δ as electrode in proton ceramic fuel cells

The H₂S-tolerance of SrFe_0.75Mo_0.25O_3-δ (SFM) electrodes has been investigated in symmetric proton ceramic fuel cells (PCFC) with BaZr_0.8Ce_0.1Y_0.1O_3-δ (BZCY81) electrolyte. The ionic conductivity of the electrolyte under wet reducing conditions was found to be insignificantly affected in the presence of up to 5000 ppm H₂S. The fuel cell exhibited an OCV of about 0.9 V at 700 °C, which dropped to about 0.6 V and 0.4 V upon exposure to 500 and 5000 ppm H₂S, respectively, on the fuel side. Post characterization of the fuel cell revealed significant degradation of the anode in terms of microstructure and chemical composition due to formation of sulfides such as SrS, MoS₂ and Fe₃S₄. Nevertheless, the fuel cell was still functional due to the sufficient electronic conductivity of some of these sulfides.     

High lithium ionic conductivity in the garnet‐type oxide Li7−2xLa3Zr2−xMoxO12 (x=0‐0.3) ceramics by sol‐gel method

Lithium garnet‐type oxides Li_7?2xLa₃Zr_2?xMo_xO₁₂ (x=0, 0.1, 0.2, 0.3) ceramics were prepared by a sol‐gel method. The influence of molybdenum on the structure, microstructure and conductivity of Li₇La₃Zr₂O₁₂ were investigated by X‐ray diffraction, scanning electron microscopy, and impedance spectroscopy. The cubic phase Li₇La₃Zr₂O₁₂ has been stabilized by partial substitution of Mo for Zr at low temperature. The introduction of Mo (x≥0.1) can accelerate densification. Li_6.6La₃Zr_1.8Mo_0.2O₁₂ sintered at lower temperature 1100°C for 3 hours exhibits highest total ionic conductivity of 5.09 × 10^?4 S/cm. Results indicate that the Mo doping LLZO synthesized by sol‐gel method effectively lowers its sintering temperature and improves the ionic conductivity.     

Investigation on Proton Conductivity of La2Ce2O7 in Wet Atmosphere: Dependence on Water Vapor Partial Pressure

The AC conductivity of fluorite‐structured La₂Ce₂O₇ ceramic was measured under air and argon with different humidity between 250 and 550 °C. It was observed that the total conductivity in wet air and argon was higher than that under dry atmospheres. The effect of water vapor partial pressure ( ) on the conductivity of La₂Ce₂O₇ in air was investigated in detail. The total conductivity increased remarkably with the water vapor partial pressure, and this phenomenon became more notable at lower temperatures. The enhancement of the conductivity was attributed to the proton conduction behavior of La₂Ce₂O₇ in wet atmospheres, and the proton conductivity reached 6.68 × 10^–5 S cm^–1 in wet air (3% H₂O) at 550 °C. The relationship between the proton conductivity (σ_H) and in wet air could be fitted to . The estimated proton transport number increased with increasing water vapor partial pressure and decreasing temperature, and varied between 0.05 and 0.89 in this study.     

Microstructure and Polarization Studies on Interlayer Free La0.65Sr0.3Co0.2Fe0.8O3–δ Cathodes Fabricated on Yttria Stabilized Zirconia by Solution Precursor Plasma Spraying

Nano‐structured cathodes of La_0.65Sr_0.3Co_0.2Fe_0.8O_3–δ (LSCF) are fabricated by solution precursor plasma spraying (SPPS) on yttria stabilized zirconia (YSZ) electrolytes (LSCF‐SPPS‐YSZ). Phase pure LSCF is obtained at all plasma power. Performances of LSCF‐SPPS‐YSZ cathodes are compared with conventionally prepared LSCF cathodes on YSZ (LSCF‐C‐YSZ) and gadolinium doped ceria (GDC) (LSCF‐C‐GDC) electrolytes. High R_p is observed in the LSCF‐C‐YSZ (∼42 Ohm cm² at 700 °C) followed by LSCF‐C‐GDC (R_p ∼ 1.5 Ohm cm² at 700 °C) cathodes. Performance of the LSCF‐SPPS‐YSZ cathodes (R_p ∼ 0.1 Ohm cm² at 700 °C) is found to be even superior to the performance of LSCF‐C‐GDC cathodes. High performance in LSCF‐SPPS‐YSZ cathodes is attributed to its nano‐structure and absence of any interfacial insulating phase which may be attributed to the low temperature at the interaction point of LSCF and YSZ and low interaction time between LSCF and YSZ during SPPS process. In the time scale of 100 h, no change in the polarization resistances is observed at 750 °C. Based on the literature and from the present studies it can be stated that SOFC with YSZ electrolyte and LSCF‐SPPS‐YSZ cathode can be operated at 750 °C for a longer duration of time and good performance can probably be achieved.     

Characterization of Ba0.5Sr0.5Co0.7In0.1Fe0.2O3−δ as the Cathode Material for Proton‐conducting SOFCs

Ba_0.5Sr_0.5Co_0.7In_0.1Fe_0.2O_3−δ powders are successfully synthesized as the cathode materials for proton‐conducting solid oxide fuel cells (SOFCs). The prepared cells consisting of the structure of a BaZr_0.1Ce_0.7Y_0.2O_3−δ (BZCY7)‐NiO anode substrate, a BZCY7 electrolyte membrane and a cathode layer, are measured from 600 to 700 °C with humidified hydrogen (ca. 3% H₂O) as the fuel. The electrochemical results show that the cell exhibits a high power density which could obtain an open‐circuit potential of 0.986 V and a maximum power density of 400.84 mW cm⁻² at 700 °C. The polarization resistance measured at the open‐circuit condition is only 0.15 Ω cm² at 700 °C.     

Electrochemical performance of intermediate temperature micro-tubular solid oxide fuel cells using porous ceria barrier layers

We describe the manufacture and electrochemical characterization of micro-tubular anode supported solid oxide fuel cells (mT-SOFC) operating at intermediate temperatures (IT) using porous gadolinium-doped ceria (GDC: Ce_0.9Gd_0.1O_2−δ) barrier layers. Rheological studies were performed to determine the deposition conditions by dip coating of the GDC and cathode layers. Two cell configurations (anode/electrolyte/barrier layer/cathode): single-layer cathode (Ni–YSZ/YSZ/GDC/LSCF) and double-layer cathode (Ni–YSZ/YSZ/GDC/LSCF–GDC/LSCF) were fabricated (YSZ: Zr_0.92Y_0.16O_2.08; LSCF: La_0.6Sr_0.4Co_0.2Fe_0.8O_3−δ). Effect of sintering conditions and microstructure features for the GDC layer and cathode layer in cell performance was studied. Current density–voltage (j–V) curves and impedance spectroscopy measurements were performed between 650–800 °C, using wet H₂ as fuel and air as oxidant. The double-cathode cells using a GDC layer sintered at 1400 °C with porosity about 50% and pores and grain sizes about 1 μm, showed the best electrochemical response, achieving maximum power densities of up to 160 mW cm⁻² at 650 °C and about 700 mW cm⁻² at 800 °C. In this case GDC electrical bridges between cathode and electrolyte are preserved free of insulating phases. A preliminary test under operation at 800 °C shows no degradation at least during the first 100 h. These results demonstrated that these cells could compete with standard IT-SOFC, and the presented fabrication method is applicable for industrial-scale.     

A Low Cost Large‐Area Solid Oxide Cells Fabrication Technology based on Aqueous Co‐Tape Casting and Co‐Sintering

Aqueous‐based tape casting is a low‐cost and environment friendly technology. In this paper, large‐area fuel electrode‐supported solid oxide cells (SOCs) were fabricated by this technology in conjunction with co‐sintering process. A 10 cm × 10 cm single cell with NiO/Zr_0.92Y_0.08O_2–δ fuel electrode, Zr_0.92Y_0.08O_2–δ electrolyte and La_0.6Sr_0.4Co_0.2Fe_0.8O_3+δ/Ce_0.9Gd_0.1O_2+δ air electrode has been successfully developed with improved electrode microstructure and hence the cell performance with the maximum power density of 534 mW cm^–2 at 850 °C with humidified H₂ as the fuel and air as the oxidant has been achieved. The optimal slurry formulations used in the fabrication of SOC were summarized for future reference purpose.     

Effect of GDC addition method on the properties of LSM–YSZ composite cathode support for solid oxide fuel cells

Equal amounts of Gd_0.1Ce_0.9O_2−δ (GDC) were added to La_0.65Sr_0.3MnO_3−δ/(Y₂O₃)_0.08(ZrO₂)_0.92 (LSM/YSZ) powder either by physical mixing or by sol–gel process, to produce a porous cathode support for solid oxide fuel cells (SOFCs). The effect of the GDC mixing method was analyzed in view of sinterability, thermal expansion coefficient, microstructure, porosity, and electrical conductivity of the LSM/YSZ composite. GDC infiltrated LSM/YSZ (G-LY) composite showed a highly porous microstructure when compared with mechanically mixed LSM/YSZ (LY) and LSM/YSZ/GDC (LYG) composites. The cathode support composites were used to fabricate the button SOFCs by slurry coating of YSZ electrolyte and a nickel/YSZ anode functional layer, followed by co-firing at 1250 °C. The G-LY composite cathode-supported SOFC showed maximum power densities of 215, 316, and 396 mW cm⁻² at 750, 800, and 850 °C, respectively, using dry hydrogen as fuel. Results showed that the GDC deposition by sol–gel process on LSM/YSZ powder before sintering is a promising technique for producing porous cathode support for the SOFCs.     

Study of Carbon Deposition Behavior on Cu–Co/CeO2–YSZ Anodes for Direct Butane Solid Oxide Fuel Cells

Electro‐catalytic activity of Cu–Co/CeO₂–YSZ anodes towards oxidation of H₂ and n‐C₄H₁₀ fuels and carbon depositions are investigated using different Cu–Co loadings. Cu–Co/CeO₂–YSZ anode based SOFCs with YSZ as electrolyte and LSM/YSZ as cathode were prepared by tape casting and wet impregnation methods and performance was analyzed using I–V characteristics and impedance spectroscopy. The Cu–Co/CeO₂–YSZ anodes with Cu–Co loading of 10, 15, and 25 wt.% produced power density of 60, 197, and 400 mW cm^–2 in H₂ and 190, 225, and 275 mW cm^–2 in n‐C₄H₁₀ at 800 °C. The power density is increased with the increase in Cu–Co loading in Cu–Co/CeO₂–YSZ anodes. The electrochemical impedance spectra shows less ohmic and polarization resistance for 25 wt.% Cu–Co loading in comparison to 10 and 15 wt.% Cu–Co. Scanning electron microscopy and high resolution transmission electron microscopy shows that the carbon fibers formed are hollow in nature with 70 nm size, whereas, thermal gravimetric analysis and X‐ray diffraction points out that they are amorphous in nature. The performance degradation of Cu–Co/CeO₂–YSZ anodes in n‐C₄H₁₀ in 16 h is attributed to increasing amount of carbon deposition with time, which is contrary to our earlier observation in Cu‐Fe/CeO₂–YSZ anode.