PrBa0.5Sr0.5Co2O5+x as cathode material based on LSGM and GDC electrolyte for intermediate-temperature solid oxide fuel cells

PrBa_0.5Sr_0.5Co₂O_5+x (PBSC) oxides have been evaluated as cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCs) with Ce_0.9Gd_0.1O_1.95 (GDC) and La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ (LSGM) as electrolytes. XRD results show that PBSC cathode is chemically compatible with the intermediate-temperature electrolyte materials GDC and LSGM. The maximum electrical conductivity is 1522 S cm⁻¹ at 100 °C and its value is higher than 581 S cm⁻¹ over the whole temperature range investigated. Microstructures show that the contact between PBSC and LSGM is better than that between PBSC and GDC. The area-specific resistances (ASRs) of PBSC cathode on GDC and LSGM electrolytes are 0.048 and 0.027 Ωcm² at 800 °C, respectively. The electrolyte-supported (thickness of electrolyte is 300 μm) fuel cells generate good performance with the maximum power densities of 617 mW cm⁻² on GDC electrolyte and 1021 mW cm⁻² on LSGM electrolyte at 800 °C. All results demonstrate that PBSC oxide is a very promising cathode material for application in IT-SOFCs and this cathode based on LSGM electrolyte obtained better performance than on GDC electrolyte.     

High-performance PrBaCo2O5+δ-Ce0.8Sm0.2O1.9 composite cathodes for intermediate temperature solid oxide fuel cell

PrBaCo₂O_5+δ-Ce_0.8Sm_0.2O_1.9 (PBCO-SDC) composite material are prepared and characterized as cathode for intermediate temperature solid oxide fuel cells (IT-SOFCs). The powder X-ray diffraction result proves that there are no obvious reaction between the PBCO and SDC after calcination at 1100 °C for 3 h. AC impedance spectra based on SDC electrolyte measured at intermediate temperatures shows that the addition of SDC to PBCO improved remarkably the electrochemical performance of a PBCO cathode, and that a PBCO-30SDC cathode exhibits the best electrochemical performance in the PBCO-xSDC system. The total interfacial resistances R_p is the smallest when the content of SDC is 30 wt%, where the value is 0.035 Ω cm² at 750 °C, 0.072 Ω cm² at 700 °C, and 0.148 Ω cm² at 650 °C, much lower than the corresponding interfacial resistance for pure PBCO. The maximum power density of an anode-supported single cell with PBCO-30SDC cathode, Ni-SDC anode, and dense thin SDC/LSGM (La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ)/SDC tri-layer electrolyte are 364, 521 and 741 mW cm⁻² at 700, 750 and 800 °C, respectively.     

Performances of LnBaCo2O5+x-Ce0.8Sm0.2O1.9 composite cathodes for intermediate-temperature solid oxide fuel cells

Double-perovskite oxides, LnBaCo₂O_5+x (LnBCO) (Ln = Pr, Nd, Sm, and Gd), are prepared using a solid-state reaction as cathodes for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The performances of LnBCO-Ce_0.8Sm_0.2O_1.9 (SDC) composite cathodes were investigated for IT-SOFCs on La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ (LSGM) electrolyte. The thermal expansion coefficient can be effectively reduced in the case of the composite cathodes. No chemical reactions between LnBCO cathodes and SDC electrolyte, and LnBCO and LSGM are found. The electrochemical performances of LnBCO cathodes and LnBCO-SDC composite cathodes decrease with decreasing Ln³⁺ ionic radii, which is closely related to the decrease of the electrical conductivity and fast oxygen diffusion property. The area specific resistances of the LnBCO cathodes and LnBCO-SDC composite cathodes on LSGM electrolyte are all lower than 0.13 Ω cm² and 0.15 Ω cm² at 700 °C, respectively. The maximum power densities of single-cell consisted of LnBCO-SDC composite cathodes, LSGM electrolyte, and Ni-SDC anode achieve 758-608 mW cm⁻² at 800 °C with the change from Ln = Pr to Gd, respectively. These results indicate that LnBCO-SDC composite oxides are candidates as a promising cathode material for IT-SOFCs.     

Electrochemical performance of PrBaCo2O5+δ layered perovskite as an intermediate-temperature solid oxide fuel cell cathode

PrBaCo₂O_5+δ (PBCO) powder was prepared by a combined EDTA and citrate complexing method. The electrochemical performance of PBCO as a cathode for intermediate-temperature solid oxide fuel cells (IT-SOFCs) was evaluated. A porous layer of PBCO was deposited on a 42 μm thick electrolyte consisting of Ce_0.8Sm_0.2O_1.9 (SDC), prepared by a dry-pressing process. A fuel cell with a structure PBCO/SDC/Ni-SDC provides a maximum power density of 866, 583, 313 and 115 mW cm⁻² at 650, 600, 550 and 500 °C, respectively, using hydrogen as the fuel and stationary air as the oxidant. The total resistance of the cell was about 0.41, 0.51, 0.57 and 0.77 Ω cm², respectively. This encouraging data identifies PBCO as a potential cathode material for IT-SOFCs.     

Layered perovskite GdBaCoFeO5+x as cathode for intermediate-temperature solid oxide fuel cells

A layered perovskite oxide, GdBaCoFeO_5+x (GBCF), was investigated as a novel cathode for intermediate-temperature solid oxide fuel cells (IT-SOFCs). A laboratory-sized Sm_0.2Ce_0.8O_1.9 (SDC)-based tri-layer cell of NiO–SDC/SDC/GBCF was tested under intermediate-temperature conditions of 550–650 °C with humidified H₂ (∼3% H₂O) as a fuel and the static ambient air as oxidant. A maximal power density of 746 mW cm⁻² was achieved at 650 °C. The interfacial polarization resistance was as low as 0.42, 0.18 and 0.11 Ω cm² at 550, 600 and 650 °C, respectively. The experimental results indicate that the layered perovskite GBCF is a promising cathode candidate for IT-SOFCs.     

BaCo0.7Fe0.2Nb0.1O3−δ as cathode material for intermediate temperature solid oxide fuel cells

BaCo_0.7Fe_0.2Nb_0.1O_3−δ (BCFN) has been synthesized and characterized as cathode material for intermediate temperature solid oxide fuel cells (IT-SOFCs) using La_0.8Sr_0.2Ga_0.83Mg_0.17O_3−δ (LSGM) electrolyte. X-ray diffraction results show that pure cubic BCFN perovskite phase can be obtained at 950 °C through solid state reactions of BaCO₃, Co₃O₄, Fe₂O₃ and Nb₂O₅. The electrical conductivity of BCFN increases with the increase in oxygen partial pressure, indicating that BCFN is a p-type semiconductor. The polarization resistance of the BCFN cathode with LSGM electrolyte is only 0.06 Ω cm² at 750 °C in air under open-circuit conditions. The overpotential at a current density of 1 A cm⁻² in oxygen was only about 0.04 V at 750 °C. Peak power densities of 550, 770 and 980 mW cm⁻² have been achieved on LSGM-electrolyte supported single cells with the configuration of Ni-Gd_0.1Ce_0.9O_1.95|La_0.4Ce_0.6O₂|LSGM|BCFN at 700, 750 and 800 °C, respectively. These results indicate that BCFN is a very promising cathode candidate for IT-SOFCs with LSGM electrolyte.     

Preparation and characterization of new cobalt-free cathode Pr0.5Sr0.5Fe0.8Cu0.2O3−δ for IT-SOFC

A new cobalt-free perovskite oxide Pr_0.5Sr_0.5Fe_0.8Cu_0.2O_3−δ (PSFC) has been synthesized and evaluated as cathode material for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The chemical compatibility of PSFC with Sm_0.2Ce_0.8O_1.9 (SDC) electrolyte has be proven by XRD, and its electrical conductivity reaches the maximum value of 264.1 S cm⁻¹ at 475 °C. Symmetrical cells with the configuration of PSFC/SDC/PSFC are used for the impedance study and the polarization resistance (Rp) of PSFC cathode is as low as 0.050 Ω cm² at 700 °C. Single cells, consisting of Ni–YSZ/YSZ/SDC/PSFC structure, are assembled and tested from 550 °C to 800 °C with wet hydrogen (∼3% H₂O) as fuel and static air as oxidant. A maximum power density of 1077 mW cm⁻² is obtained at 800 °C. All the results suggest that the cobalt-free perovskite oxide PSFC is a very promising cathode material for application in IT-SOFC.     

Evaluation of Sr substituted Nd2CuO4 as a potential cathode material for intermediate-temperature solid oxide fuel cells

The Nd_1.7Sr_0.3CuO₄ (NSCu) material with perovsikite-related structure was synthesized and evaluated as a new cathode for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The crystal structure, thermal expansion, electrical conductivity and electrochemical performance of NSCu have been investigated by X-ray diffraction, a dilatometer, DC four-probe method, AC impedance and cyclic voltammetry (CV) techniques. The polarization resistances of NSCu cathode on Sm-doped ceria (SDC) electrolyte in air were 0.07 Ω cm², 0.24 Ω cm² and 1.60 Ω cm² at 800 °C, 700 °C and 600 °C, respectively. The results demonstrated that both impedance and CV methods are consistent with high exchange current density i₀ (390.7 mA/cm² and 76.1 mA/cm² at 800 °C and 700 °C.), making NSCu a promising cathode material for the IT-SOFCs based on doped ceria electrolytes.     

Synthesis,electrical and electrochemical properties of Ba0.5Sr0.5Zn0.2Fe0.8O3−δ perovskite oxide for IT-SOFC cathode

The Ba_0.5Sr_0.5Zn_0.2Fe_0.8O_3−δ (BSZF) complex oxide with cubic perovskite structure was synthesized and examined as a new cobalt-free cathode for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The electrical conductivity was relatively low with a peak value of 9.4 S cm⁻¹ at about 590 °C, which was mainly caused by the high concentration of oxygen vacancy and the doping of bivalent zinc in B-sites. At 650 °C and under open circuit condition, symmetrical BSZF cathode on Sm-doped ceria (SDC) electrolyte showed polarization resistances (R_p) of 0.48 Ω cm² and 0.35 Ω cm² in air and oxygen, respectively. The dependence of R_p with oxygen partial pressure indicated that the rate-limiting step for oxygen reduction was oxygen adsorption/desorption kinetics. Using BSZF as the cathode, the wet hydrogen fueled Ni + SDC anode-supported single cell exhibited peak power densities of 392 mW cm⁻² and 626 mW cm⁻² at 650 °C when stationary air and oxygen flux were used as oxidants, respectively.     

Combustion synthesis and properties of highly phase-pure perovskite electrolyte Co-doped La0.9Sr0.1Ga0.8Mg0.2O2.85 for IT-SOFCs

The highly phase-pure perovskite electrolyte, La_0.9Sr_0.1Ga_0.8Mg_0.115Co_0.085O_2.85 (LSGMCO), was prepared by means of glycine–nitrate process (GNP) for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The perovskite phase evolution, sintering, electrical conductivity and electrochemical performance of LSGMCO were investigated. The results show that the highly phase-pure perovskite electrolyte LSGMCO can be obtained after calcining at 1150 °C. The sample sintered at 1450 °C for 20 h in air exhibited a better sinterability, and the relative density of LSGMCO was higher than 95%. The stoichiometric indexes of the elements in the sintered sample LSGMCO determined experimentally by EDS were in good agreement with the nominal composition. The electrical conductivities of the sample were 0.094 and 0.124 S· cm⁻¹ at 800 °C and 850 °C in air, respectively. The ionic conduction of the sample was dominant at high temperature with the higher activation energies. While at lower temperature the electron hole conduction was predominated with the lower activation energies. The maximum power densities of the single cell fabricated with LSGMCO electrolyte with Ce_0.8Sm_0.2O_1.9 (SDC) interlayer, SmBaCo₂O_5+x cathode and NiO/SDC anode achieved 643 and 802 mW cm⁻² at 800 °C and 850 °C, respectively.     

Intermediate-temperature electrochemical performance of a polycrystalline PrBaCo2O5+δ cathode on samarium-doped ceria electrolyte

A-site cation-ordered PrBaCo₂O_5+δ (PrBC) double perovskite oxide was synthesized and evaluated as the cathode of an intermediate-temperature solid-oxide fuel cell (IT-SOFC) on a samarium-doped ceria (SDC) electrolyte. The phase reaction between PrBC and SDC was weak even at 1100 °C. The oxygen reduction mechanism was investigated by electrochemical impedance spectroscopy characterization. Over the intermediate-temperature range of 450–700 °C, the electrode polarization resistance was mainly contributed from oxygen-ion transfer through the electrode–electrolyte interface and electron charge transfer over the electrode surface. An area-specific resistance as low as ∼0.4 Ω cm² was measured at 600 °C in air, based on symmetric cell test. A thin-film SDC electrolyte fuel cell with PrBC cathode was fabricated which delivered attractive peak power densities of 620 and 165 mW cm⁻² at 600 and 450 °C, respectively.     

Properties and performance of Ba0.5Sr0.5Co0.8Fe0.2O3−δ + Sm0.2Ce0.8O1.9 composite cathode

The properties and performance of Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3−δ (BSCF) + Sm_0.2Ce_0.8O_1.9 (SDC) (70:30 in weight ratio) composite cathode for intermediate-temperature solid-oxide fuel cells were investigated. Mechanical mixing of BSCF with SDC resulted in the adhesion of fine SDC particles to the surface of coarse BSCF grains. XRD, SEM-EDX and O₂-TPD results demonstrated that the phase reaction between BSCF and SDC was negligible, constricted only at the BSCF and SDC interface, and throughout the entire cathode with the formation of new (Ba,Sr,Sm,Ce)(Co,Fe)O_3−δ perovskite phase at a firing temperature of 900, 1000, and ≥ 1050 °C, respectively. The BSCF + SDC electrode sintered at 1000 °C showed an area specific resistance of ∼0.064 Ω cm² at 600 °C, which is a slight improvement over the BSCF (0.099 Ω cm²) owing to the enlarged cathode surface area contributed from the fine SDC particles. A peak power density of 1050 and ∼382 mW cm⁻² was reached at 600 and 500 °C, respectively, for a thin-film electrolyte cell with the BSCF + SDC cathode fired from 1000 °C.     

La2NiO4+δ potential cathode material on La0.9Sr0.1Ga0.8Mg0.2O2.85 electrolyte for intermediate temperature solid oxide fuel cell

La₂NiO_4+δ, a mixed ionic-electronic conducting oxide with K₂NiF₄ type structure, has been studied as cathode material with La_0.9Sr_0.1Ga_0.8Mg_0.2O_2.85 (LSGM) electrolyte for intermediate solid oxide fuel cells (IT-SOFCs). XRD results reveal excellent chemical compatibility between the La₂NiO_4+δ sample and LSGM electrolyte.A single cell (0.22 cm² active area) was fabricated with La₂NiO_4+δ as cathode, Ni-Sm_0.2Ce_0.8O_1.9 (2:1; w/w) as anode and LSGM as electrolyte. A thin buffer layer of Sm_0.2Ce_0.8O_1.9 (SDC) between anode and electrolyte was used to avoid possible interfacial reactions. The cell was tested under humidified H₂ and stationary air as fuel and oxidant, respectively. The electrochemical behaviour was evaluated by means of current-voltage curves and impedance spectroscopy. Microstructure and morphology of the cell components were analysed by SEM-EDX after testing.The maximum power densities were 160, 226, and 322 mW cm⁻² at 750, 800 and 850 °C, respectively with total polarisation resistances of 0.77, 0.48 and 0.31 Ω cm² at these temperatures. Cell performance remained stable when a current density of 448 mA cm⁻² was demanded for 144 h at 800 °C, causing no apparent degradation in the cell. The performance of this material may be further improved by reducing the electrolyte thickness and optimisation of the electrode microstructure.     

Thermal expansion and electrochemical properties of Ni-doped GdBaCo2O5+δ double-perovskite type oxides

Layered GdBaCo_2 −x Ni_xO_5 + δ (0 ≤ x ≤ 0.3) complex oxides were synthesized and investigated as cathodes for intermediate-temperature solid oxide fuel cell (IT-SOFCs). All compositions formed an orthorhombic double-perovskite structure after calcination at 1000 °C for 5 h. The thermal expansion coefficient (TEC) was effectively decreased due to the partial substitution of Ni for Co, but the cathodic polarization resistance slightly increased with the increasing Ni content. Among the tested oxides, the GdBaCo_1.7Ni_0.3O_5 + δ composition showed a fairly reduced TEC (15.5 × 10⁻⁶ K⁻¹) and reasonably low polarization resistances (e.g., 0.54 Ωcm² at 600 °C), which was considered as a promising candidate for IT-SOFCs.     

Co-doped Sr2FeNbO6 as cathode materials for intermediate-temperature solid oxide fuel cells

Sr₂Fe_1−xCo_xNbO₆ (0.1 ≤ x ≤ 0.9) (SFCN) oxides with perovskite structure have been developed as the cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCs). These materials are synthesized via solid-state reaction and characterized by XRD, SEM, electrical conductivity, AC impedance spectroscopy and DC polarization measurements. The reactivity tests show that the Sr₂Fe_1−xCo_xNbO₆ electrodes are chemically compatible with the Zr_0.85Y_0.15O_1.925 (YSZ) and Ce_1.9Gd_0.1O_1.95 (CGO) electrolytes at 1200 °C, and the electrode forms a good contact with the electrolyte after sintering at 1200 °C for 12 h. The total electrical conductivity that has a considerable effect on the electrode properties is determined in a temperature range from 200 °C to 800 °C. The highest conductivity of 5.7 S cm⁻¹ is found for Sr₂Fe_0.1Co_0.9NbO₆ at 800 °C in air. The electrochemical performances of these cathode materials are studied using impedance spectroscopy at various temperatures and oxygen partial pressures. Two different kinds of reaction rate-limiting steps exist on the Sr₂Fe_0.1Co_0.9NbO₆ electrode, depending on the temperature. The Sr₂Fe_0.1Co_0.9NbO₆ electrode on CGO electrolyte exhibits a polarization resistance of 0.74 Ω cm² at 750 °C in air, which indicates that the Sr₂Fe_0.1Co_0.9NbO₆ electrode is a promising cathode material for IT-SOFCs.     

Electrochemical performances of NdBa0.5Sr0.5Co2O5+x as potential cathode material for intermediate-temperature solid oxide fuel cells

Layered perovskite oxide NdBa_0.5Sr_0.5Co₂O_5+x is investigated as a cathode material for intermediate-temperature solid oxide fuel cells. The NBSC cathode is chemically compatible with the electrolyte La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ (LSGM) at temperatures below 1000 °C. It is metallic in nature and the maximum and minimum conductivities are 1368 S cm⁻¹ at 100 °C and 389 S cm⁻¹ at 850 °C. The area specific resistance (ASR) value for the NBSC cathode is as low as 0.023 Ω cm² at 850 °C. The electrolyte-supported fuel cell generates good performance with the maximum power density of 904, 774 and 556 mW cm⁻² at 850, 800 and 750 °C, respectively. Preliminary results indicate that NBSC is promising as a cathode for IT-SOFCs.     

Preparation and characterization of Pr1−xSrxFeO3 cathode material for intermediate temperature solid oxide fuel cells

A kind of cathode material of Pr_1−xSr_x FeO₃ (x = 0–0.5) for intermediate temperature solid oxide fuel cells (IT-SOFCs) was prepared by the coprecipitation method. Crystal structure, thermal expansion, electrical conductivity and electrochemical performance of the Pr_1−xSr_xFeO₃ perovskite oxide cathodes were studied by different methods. The results revealed that Pr_l−xSr_xFeO₃ exhibited similar orthorhombic structure from x = 0.1 to 0.3 and took cubic structure when x = 0.4–0.5. The unit cell volume decreased and the thermal expansion coefficient (TEC) of the materials increased as the strontium content increased. When 0 < x ≤ 0.3, the samples exhibited good thermal expansion compatibility with YSZ electrolyte. The electrical conductivity increased with the increasing of doped strontium content. When x = 0.3–0.5, the electrical conductivities were higher than 100 S cm⁻¹. The conductivity of Pr_0.8Sr_0.2FeO₃ was 78 S cm⁻¹ at 800 °C. Compared with the La_0.8Sr_0.2MnO₃ cathode, Pr_0.8Sr_0.2FeO₃ showed higher polarization current density and lower polarization resistance (0.2038 Ω cm²). The value of I₀ for Pr_0.8Sr_0.2FeO₃ at 800 °C is 123.6 mA cm⁻². It is higher than that of La_0.8Sr_0.2MnO₃. Therefore, Pr_1−xSr_xFeO₃ can be considered as a candidate cathode material for IT-SOFCs.     

Ba0.5Sr0.5Co0.8Fe0.2O3 − δ + LaCoO3 composite cathode for Sm0.2Ce0.8O1.9-electrolyte based intermediate-temperature solid-oxide fuel cells

A novel Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3 − δ + LaCoO₃ (BSCF + LC) composite oxide was investigated for the potential application as a cathode for intermediate-temperature solid-oxide fuel cells based on a Sm_0.2Ce_0.8O_1.9 (SDC) electrolyte. The LC oxide was added to BSCF cathode in order to improve its electrical conductivity. X-ray diffraction examination demonstrated that the solid-state reaction between LC and BSCF phases occurred at temperatures above 950 °C and formed the final product with the composition: La_0.316Ba_0.342Sr_0.342Co_0.863Fe_0.137O_3 − δ at 1100 °C. The inter-diffusion between BSCF and LC was identified by the environmental scanning electron microscopy and energy dispersive X-ray examination. The electrical conductivity of the BSCF + LC composite oxide increased with increasing calcination temperature, and reached a maximum value of ∼300 S cm⁻¹ at a calcination temperature of 1050 °C, while the electrical conductivity of the pure BSCF was only ∼40 S cm⁻¹. The improved conductivity resulted in attractive cathode performance. An area-specific resistance as low as 0.21 Ω cm² was achieved at 600 °C for the BSCF (70 vol.%) + LC (30 vol.%) composite cathode calcined at 950 °C for 5 h. Peak power densities as high as ∼700 mW cm⁻² at 650 °C and ∼525 mW cm⁻² at 600 °C were reached for the thin-film fuel cells with the optimized cathode composition and calcination temperatures.     

Electrochemical performance of (Ba0.5Sr0.5)0.9Sm0.1Co0.8Fe0.2O3−δ as an intermediate temperature solid oxide fuel cell cathode

This study presents the electrochemical performance of (Ba_0.5Sr_0.5)_0.9Sm_0.1Co_0.8Fe_0.2O_3−δ (BSSCF) as a cathode material for intermediate temperature solid oxide fuel cells (IT-SOFC). AC-impedance analyses were carried on an electrolyte supported BSSCF/Sm_0.2Ce_0.8O_1.9 (SDC)/Ag half-cell and a Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3−δ (BSCF)/SDC/Ag half-cell. In contrast to the BSCF cathode half-cell, the total resistance of the BSSCF cathode half-cell was lower, e.g., at 550 °C; the values for the BSSCF and BSCF were 1.54 and 2.33 Ω cm², respectively. The cell performance measurements were conducted on a Ni-SDC anode supported single cell using a SDC thin film as electrolyte, and BSSCF layer as cathode. The maximum power densities were 681 mW cm⁻² at 600 °C and 820 mW cm⁻² at 650 °C.     

Novel YBaCo3.2Ga0.8O7+δ as a cathode material and performance optimization for IT-SOFCs

The YBaCo_3.2Ga_0.8O_7+δ (YBCGO) oxide has been developed as new cathode material based on La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ (LSGM) electrolyte for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The electrical conductivity of YBCGO sample reaches 1.4–2.1 S cm⁻¹ in the temperature range 650–800 °C. The thermal expansion coefficient (TEC) value of YBCGO is 8.6 × 10⁻⁶ K⁻¹ in the range of 30–1000 °C. The area specific resistance (ASR) of a YBCGO cathode with LSGM electrolyte is 0.111 Ω cm² at 800 °C and it decreases to 0.047 Ω cm² when PrBaCo₂O_5+δ (PBCO) is added to form a YBCGO–PBCO composite cathode. Peak power densities of single cells using a pure YBCGO cathode and a YBCGO–PBCO composite cathode are 395 and 531 mW cm⁻² at 800 °C, respectively. The results of this study demonstrate that YBCGO can be a promising cathode material for IT-SOFCs.