Electrochemical performance of novel cobalt-free oxide Ba0.5Sr0.5Fe0.8Cu0.2O3−δ for solid oxide fuel cell cathode

A novel cobalt-free perovskite oxide Ba_0.5Sr_0.5Fe_0.8Cu_0.2O_3−δ (BSFC) is employed as a cathode material for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The electrical conductivity of BSFC reaches the maximum value of 57 S cm⁻¹ at 600 °C. Symmetrical electrochemical cell with the configuration of BSFC/SDC/BSFC is applied for the impedance study and area specific resistance (ASR) of BSFC cathode material is as low as 0.137 Ω cm² at 700 °C. The single cell, consisting of BSFC/SDC/NiO-SDC structure, is assembled and tested from 550 to 700 °C with humidified hydrogen (∼3% H₂O) as the fuel and the static air as the oxidant. A maximum power density of 718 mW cm² is obtained at 700 °C for the single cell. Preliminary results demonstrate that the cobalt-free oxide BSFC is a very promising cathode material for application in IT-SOFCs.     

A cobalt-free Sm0.5Sr0.5Fe0.8Cu0.2O3−δ-Ce0.8Sm0.2O2−δ composite cathode for proton-conducting solid oxide fuel cells

A cobalt-free composite Sm_0.5Sr_0.5Fe_0.8Cu_0.2O_3−δ-Ce_0.8Sm_0.2O_2−δ (SSFCu-SDC) is investigated as a cathode for proton-conducting solid oxide fuel cells (H-SOFCs) in intermediate temperature range, with BaZr_0.1Ce_0.7Y_0.1Yb_0.1O_3−δ (BZCYYb) as the electrolyte. The XRD results show that SSFCu is chemically compatible with SDC at temperatures up to 1100 °C. The quad-layer single cells of NiO-BZCYYb/NiO-BZCYYb/BZCYYb/SSFCu-SDC are operated from 500 to 700 °C with humidified hydrogen (∼3% H₂O) as fuel and the static air as oxidant. It shows an excellent power density of 505 mW cm⁻² at 700 °C. Moreover, a low electrode polarization resistance of 0.138 Ω cm² is achieved at 700 °C. Preliminary results demonstrate that the cobalt-free SSFCu-SDC composite is a promising cathode material for H-SOFCs.     

Cobalt-free oxide Ba0.5Sr0.5Fe0.8Cu0.2O3−δ for proton-conducting solid oxide fuel cell cathode

A cobalt-free perovskite oxide Ba_0.5Sr_0.5Fe_0.8Cu_0.2O_3−δ (BSFC) is employed as a cathode material for intermediate-temperature proton-conducting solid oxide fuel cells. Symmetrical electrochemical cell with the configuration of BSFC-BZCY/BZCY/BSFC-BZCY is applied for the impedance study. The single cell, consisting of BSFC-BZCY/BZCY/NiO-BZCY structure, is assembled and tested from 600 to 700 °C with humidified hydrogen (∼3% H₂O) as the fuel and the static air as the oxidant. A maximum power density of 430 mW cm⁻² is obtained at 700 °C for the single cell. Long-term stability of the BSFC-BZCY/BZCY/NiO-BZCY single cell at 600 °C for 40 h has also been studied. Preliminary results demonstrat that cobalt-free oxide BSFC is a very promising cathode for application in proton-conducting solid oxide fuel cells.     

Nd0.5Sr0.5Fe0.8Cu0.2O3−δ–xSm0.2Ce0.8O1.9 cobalt-free composite cathodes for intermediate temperature solid oxide fuel cells

Cobalt-free composites Nd_0.5Sr_0.5Fe_0.8Cu_0.2O_3−δ (NSFCu)–xSm_0.2Ce_0.8O_1.9 (SDC) (x = 0–60 wt%) are investigated as IT-SOFC cathodes. The characteristic properties of cobalt-free composite cathodes comparing to cobalt-based composites are revealed. The DC conductivity and thermal expansion coefficient of the composite cathodes decrease with the content of SDC x, while the polarization resistance R_p shows the least value with addition of 40 wt% of SDC. The power density of the single cell with NSFCu-40% SDC composite cathode improved significantly compared with that of undoped NSFCu cathode, with peak values of 488, 623, 849 and 1052 mW cm⁻² at 600, 650, 700, and 750 °C, respectively. Moreover, the performance of the composite cathode is stable within testing period of 370 h at 700 °C, indicating that the NSFCu-40% SDC is an excellent cobalt-free composite cathode applied in IT-SOFC.     

Oxygen reduction mechanism at Ba0.5Sr0.5Co0.8Fe0.2O3−δ cathode for solid oxide fuel cell

Perovskite structure Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3−δ (BSCF) and La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ (LSGM) powders have been successfully synthesized by glycine–nitrate combustion process. A porous and crack-free BSCF cathode is obtained by spraying the slurry of BSCF powders and terpineol onto LSGM pellet. The oxygen reduction reaction mechanism has been investigated by AC impedance spectroscopy and cyclic voltammetry method. AC impedance spectroscopy analysis shows that there are two different processes in the cathode reaction which are related to oxygen dissociation/adsorption and bulk oxygen diffusion. And the molecular oxygen is involved in the rate-determining step. The polarization resistance decreases with an increase of temperature and the oxygen partial pressure. With an increase of the applied DC bias, the logarithm of the polarization resistance decreases linearly due to additional oxygen vacancies and the lowered chemical potential of oxygen at the BSCF/LSGM interface by the applied voltage. The exchange current density reaches to 182 mA cm⁻² at 700 °C, suggesting that the ORR kinetics at the BSCF/LSGM interface is high due to the excellent mixed ionic and electronic conductivity of BSCF.     

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.     

Electrospinning La0.8Sr0.2Co0.2Fe0.8O3−δ tubes impregnated with Ce0.8Gd0.2O1.9 nanoparticles for an intermediate temperature solid oxide fuel cell cathode

In order to reduce the polarization resistance of the cathode, we have developed one-dimensional (1D) nanostructured La_0.8Sr_0.2Co_0.2Fe_0.8O_3−δ (LSCF) tubes/Ce_0.8Gd_0.2O_1.9 (GDC) nanoparticles composite cathodes for solid oxide fuel cell. Uniform LSCF/PVP composite nanofibers have been firstly synthesized by a single-nozzle electrospinning technique, followed by firing at 800 °C for 2 h to form one-dimensional LSCF tubes. Subsequently, the GDC phases were introduced into tube structured LSCF scaffold pre-sintered on a GDC pellet by a multi-impregnation process. Electrochemical Impedance spectra reveal that nanostructured LSCF tubes/GDC nanoparticles composite cathodes have a better electrochemical performance, achieving area-specific resistances of 4.70, 1.12, 0.27 and 0.07 Ω cm² at 500, 550, 600 and 650 °C for the composite of GDC and LSCF in a weight ratio of 0.52:1. The low ASR values are mainly related to its optimal microstructure with larger triple-phase boundaries and higher porosity. These results suggest that LSCF tube/GDC nanoparticle composite can be an alternative cathode material for intermediate temperature solid oxide fuel cell (IT-SOFC).     

Fabrication and characterization of Sm0.2Ce0.8O2−δ-Sm0.5Sr0.5CoO3−δ composite cathode for anode supported solid oxide fuel cell

The Sm_0.5Sr_0.5CoO_3−δ (SSC) with perovskite structure is synthesized by the glycine nitrate process (GNP). The phase evolution of SSC powder with different calcination temperatures is investigated by X-ray diffraction and thermogravimetric analyses. The XRD results show that the single perovskite phase of the SSC is completely formed above 1100 °C. The anode-supported single cell is constructed with a porous Ni-yttria-stabilized zirconia (YSZ) anode substrate, an airtight YSZ electrolyte, a Sm_0.2Ce_0.8O_2−δ (SDC) barrier layer, and a screen-printed SSC-SDC composite cathode. The SEM results show that the dense YSZ electrolyte layer exhibits the good interfacial contact with both the Ni-YSZ and the SDC barrier layer. The porous SSC-SDC cathode shows an excellent adhesion with the SDC barrier layer. For the performance test, the maximum power densities are 464, 351 and 243 mW cm⁻² at 800, 750 and 700 °C, respectively. According to the results of the electrochemical impedance spectroscopy (EIS), the charge-transfer resistances of the electrodes are 0.49 and 1.24 Ω cm², and the non charge-transfer resistances are 0.48 and 0.51 Ω cm² at 800 and 700 °C, respectively. The cathode material of SSC is compatible with the YSZ electrolyte via a delicate scheme employed in the fabrication process of unit cell.     

Cathode reaction mechanism of porous-structured Sm0.5Sr0.5CoO3−δ and Sm0.5Sr0.5CoO3−δ/Sm0.2Ce0.8O1.9 for solid oxide fuel cells

The cathode reaction mechanism of porous Sm_0.5Sr_0.5CoO_3−δ, a mixed ionic and electronic conductor (MIEC), is studied through a comparison with the composite cathode Sm_0.5Sr_0.5CoO_3−δ/Sm_0.2Ce_0.8O_1.9. First, the cathodic behaviour of porous Sm_0.5Sr_0.5CoO_3−δ and Sm_0.5Sr_0.5CoO_3−δ/Sm_0.2Ce_0.8O_1.9 are observed for micro-structure and impedance spectra according to Sm_0.2Ce_0.8O_1.9 addition, thermal cycling and long-term properties. The cathode reaction mechanism is discussed in terms of frequency response, activation energy, reaction order and electrode resistance for different oxygen partial pressures p(O₂) at various temperatures. Three elementary steps are considered to be involved in the cathodic reaction: (i) oxygen ion transfer at the cathode-electrolyte interface; (ii) oxygen ion conduction in the bulk cathode; (iii) gas phase diffusion of oxygen. A reaction model based on the empirical equivalent circuit is introduced and analyzed using the impedance spectra. The electrode resistance at high frequency (R_c,HF) in the impedance spectra represents reaction steps (i), due to its fast reaction rate. The electrode resistance at high frequency is independent of p(O₂) at a constant temperature because the semicircle of R_c,HF in the complex plane of the impedance spectra is held constant for different values of p(O₂). Reaction steps (ii) and (iii) are the dominant processes for a MIEC cathode, according to the analysis results. The proposed cathode reaction model and results for a solid oxide fuel cell (SOFC) well describe a MIEC cathode with high ionic conductivity, and assist the understanding of the MIEC cathode reaction mechanism.     

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.     

Characteristics of Ba0.5Sr0.5Co0.8Fe0.2O3−δ–La0.9Sr0.1Ga0.8Mg0.2O3−δ composite cathode for solid oxide fuel cell

Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3−δ–La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ composite cathodes are prepared successfully using combustion synthesis method. Microstructure, chemical compatibility and electrochemical performance have been investigated and analyzed in detail. SEM micrographs show that a structure with porosity and well-necked particles forms after sintering at 1000 °C in the composites. Grain growth is suppressed by addition of La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ phase and grain sizes decrease with increasing weight percent of La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ phase in the composites. Phase analysis demonstrates that chemical compatibility between Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3−δ and La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ is excellent when the weight percent of La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ in the composite is not more than 40%. Through fitting ac impedance spectra, it is found that the ohmic resistance and polarization resistance decrease with increasing La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ content. The polarization resistance reaches a minimum at about 30 and 40 wt.% La_0.9Sr_0.1Ga_0.8Mg_0.2O_3−δ in the composite.     

High performance proton-conducting solid oxide fuel cells with a stable Sm0.5Sr0.5Co3−δ-Ce0.8Sm0.2O2−δ composite cathode

A Sm_0.5Sr_0.5CoO_3−δ-Ce_0.8Sm_0.2O_2−δ (SSC-SDC) composite is employed as a cathode for proton-conducting solid oxide fuel cells (H-SOFCs). BaZr_0.1Ce_0.7Y_0.2O_3−δ (BZCY) is used as the electrolyte, and the system exhibits a relatively high performance. An extremely low electrode polarization resistance of 0.066 Ω cm² is achieved at 700 °C. The maximum power densities are: 665, 504, 344, 214, and 118 mW cm⁻² at 700, 650, 600, 550, and 500 °C, respectively. Moreover, the SSC-SDC cathode shows an essentially stable performance for 25 h at 600 °C with a constant output voltage of 0.5 V. This excellent performance implies that SSC-SDC, which is a typical cathode material for SOFCs based on oxide ionic conductor, is also a promising alternative cathode for H-SOFCs.     

Enhanced electrochemical performance of solution impregnated La0.8Sr0.2Co0.8Ni0.2O3−δ cathode for intermediate temperature solid oxide fuel cells

Solution impregnated La_0.8Sr_0.2Co_0.8Ni_0.2O₃ + Gd-doped CeO₂ (LSCN + GDC) cathodes for intermediate temperature solid oxide fuel cells (IT-SOFC) are prepared and their electrochemical properties are evaluated and compared with the conventional LSCN cathodes. The results indicate that the cathode performance can be enhanced by the presence of the nanosized microstructure produced with the solution impregnation method. It is determined that the amount of LSCN loading in the LSCN + GDC composite cathode needs to be higher than 35 wt% in order to achieve a performance superior to that of the conventional LSCN cathode. The optimum amount of LSCN loading is in the range of 45-55 wt% with an activation energy near 1.32 eV for oxygen reduction. At temperatures between 600 and 750 °C, the polarization resistance of the 55 wt% LSCN loaded LSCN + GDC cathode is in the range of 1.07 and 0.08 Ω cm², which is only about one half of that for the conventional cathode.     

A cobalt-free Sm0.5Sr0.5FeO3−δ–BaZr0.1Ce0.7Y0.2O3−δ composite cathode for proton-conducting solid oxide fuel cells

A cobalt-free Sm_0.5Sr_0.5FeO_3−δ–BaZr_0.1Ce_0.7Y_0.2O_3−δ (SSF–BZCY) was developed as a composite cathode material for proton-conducting solid oxide fuel cells (H-SOFC) based on proton-conducting electrolyte of stable BZCY. The button cells of Ni-BZCY/BZCY/SSF–BZCY were fabricated and tested from 550 to 700 °C with humidified H₂ (～3% H₂O) as a fuel and ambient oxygen as oxidant. An open-circuit potential of 1.024 V, maximum power density of 341 mW cm⁻², and a low electrode polarization resistance of 0.1 Ω cm² were achieved at 700 °C. The experimental results indicated that the SSF–BZCY composite cathode is a good candidate for cathode material.     

X-ray photoelectron spectroscopic studies of Ba0.5Sr0.5Co0.8Fe0.2O3−δ cathode for solid oxide fuel cells

The Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3−δ (BSCF) cathode for solid oxide fuel cell has been prepared by glycine–nitrate combustion process. Crystal structure and chemical state of BSCF have been studied by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). XRD pattern indicates that a single cubic perovskite phase of BSCF oxide is successfully obtained after calcination at 850 °C for 2 h. XPS results show there exists a little amount of SrCO₃ in the surface of BSCF. Co2p spectra indicate that some Co³⁺ ions have changed into Co⁴⁺ ions to maintain the electrical neutrality. O1s spectra present that adsorbed oxygen species appear in the surface BSCF oxide.     

Electrochemical performance of La0.7Sr0.3CuO3−δ–Sm0.2Ce0.8O2−δ functional graded composite cathode for intermediate temperature solid oxide fuel cells

The fabrication and electrochemical properties of graded La_0.7Sr_0.3CuO_3−δ–Sm_0.2Ce_0.8O_2−δ (LSCu–SDC) composite cathodes were investigated in this paper. The phase composition, microstructure and electrochemical properties of the electrodes were characterized using X-ray diffraction (XRD), electron microscopy, electrochemical impedance spectroscopy (EIS) and cathodic polarization examinations. The results showed that the triple-layer graded cathode had super electrochemical performance comparing with the monolayer cathode. The graded LSCu–SDC cathode showed a polarization resistance of 0.094 Ωcm², a value much lower than the monolayer LSCu cathode of 0.234 Ωcm² at 800 °C in air. The current density of the graded cathode was 0.341 A cm⁻², more than double higher than monolayer LSCu of 0.146 A cm⁻² at an overpotential of 30 mV. The improved electrochemical performance could be attributed to the improved physical and chemical compatibility of the cathode layers in graded compositions with SDC electrolyte as well as the enlargement of triple-phase boundary for oxygen reduction.     

Thermal, electrical and electrochemical characteristics of Ba1−xSrxCo0.8Fe0.2O3−δ cathode material for intermediate temperature solid oxide fuel cells

Ba_1−xSr_xCo_0.8Fe_0.2O_3−δ (x = 0.3-0.9) perovskite oxides have been studied as cathode material for intermediate temperature solid oxide fuel cells (IT-SOFCs). The structural characteristics, temperature dependent weight loss, thermal expansion, electrical conductivity, and electrochemical properties in combination with YSZ electrolyte together with an SDC buffer layer were characterized by X-ray diffraction (XRD), thermogravimetric analysis (TG), dilatometry, DC four probe conductivity measurement and electrochemical impedance spectroscopy (EIS) techniques respectively. XRD study revealed the lattice parameter and unit cell volume decrease with increase in Sr⁺² content at the A-site. TEC and electrical conductivity were found to increase with increasing Sr⁺² content. Electrical conductivity was found to be dependent on the thermal history of the samples. Polarization resistance of the samples with SDC buffered YSZ electrolyte decreased with increasing Sr⁺² content which was ascribed to the higher conductivity with improved oxygen adsorption/desorption and oxygen ions diffusion processes. The intrinsic oxygen reduction reaction rate also increased with Sr⁺² content at the A-site. The exchange current for intrinsic oxygen reduction reaction at 700 °C was found to be 50.0 mA cm⁻² for Ba_0.3Sr_0.7Co_0.8Fe_0.2O_3−δ; a value which is about 50% higher than that for Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3−δ, a widely studied cathode material. Therefore, the present composition may be a potential cathode material for IT-SOFC application.     

Characterization of nanosized Ce0.8Sm0.2O1.9-infiltrated Sm0.5Sr0.5Co0.8Cu0.2O3−δ cathodes for solid oxide fuel cells

This study investigates the microstructure and electrochemical properties of Sm_0.5Sr_0.5Co_0.8Cu_0.2O_3−δ (SSC-Cu) cathode infiltrated with Ce_0.8Sm_0.2O_1.9 (SDC). The newly formed nanosized electrolyte material on the cathode surface, leading the increase in electrochemical performances is mainly attributed to the creation of electrolyte/cathode phase boundaries, which considerably increases the electrochemical sites for oxygen reduction reaction. Based on the experiment results, the 0.4 M SDC infiltration reveals the lowest cathode polarization resistance (R_P), the cathode polarization resistances (R_p) are 0.117, 0.033, and 0.011 Ω cm² at 650, 750, and 850 °C, and the highest peak power density, are 439, 659, and 532 mW cm⁻² at 600, 700, and 800 °C, respectively. The cathode performance in SOFCs can be significantly improved by infiltrating nanoparticles of SDC into an SSC-Cu porous backbone. This study reveals that the infiltration approach may apply in SOFCs to improve their electrochemical properties.     

(La,Pr)0.8Sr0.2FeO3−δ–Sm0.2Ce0.8O2−δ composite cathode for proton-conducting solid oxide fuel cells

Mixed rare-earth (La, Pr)_0.8Sr_0.2FeO_3−δ–Sm_0.2Ce_0.8O_2−δ (LPSF–SDC) composite cathode was investigated for proton-conducting solid oxide fuel cells based on protonic BaZr_0.1Ce_0.7Y_0.2O_3−δ (BZCY) electrolyte. The powders of La_0.8−xPr_xSr_0.2FeO_3−δ (x = 0, 0.2, 0.4, 0.6), Sm_0.2Ce_0.8O_2−δ (SDC) and BaZr_0.1Ce_0.7Y_0.2O_3−δ (BZCY) were synthesized by a citric acid-nitrates self-propagating combustion method. The XRD results indicate that La_0.8−xPr_xSr_0.2FeO_3−δ samples calcined at 950 °C exhibit perovskite structure and there are no interactions between LPSF0.2 and SDC at 1100 °C. The average thermal expansion coefficient (TEC) of LPSF0.2–SDC, BZCY and NiO-BZCY is 12.50 × 10⁻⁶ K⁻¹, 13.51 × 10⁻⁶ K⁻¹ and 13.47 × 10⁻⁶ K⁻¹, respectively, which can provide good thermal compatibility between electrodes and electrolyte. An anode-supported single cell of NiO-BZCY|BZCY|LPSF0.2–SDC was successfully fabricated and operated from 700 °C to 550 °C with humidified hydrogen (∼3% H₂O) as fuel and the static air as oxidant. A high maximum power density of 488 mW cm⁻², an open-circuit potential of 0.95 V, and a low electrode polarization resistance of 0.071 Ω cm² were achieved at 700 °C. Preliminary results demonstrate that LPSF0.2–SDC composite is a promising cathode material for proton-conducting solid oxide fuel cells.     

LaCo0.6Ni0.4O3−δ as cathode contact material for intermediate temperature solid oxide fuel cells

LaCo_0.6Ni_0.4O_3−δ (LCN64) was prepared through the polymeric steric entrapment precursor route with Polyvinyl alcohol (PVA) as the entrapment agent and was evaluated as a contact material between the metallic interconnect and the cathode in planar intermediate temperature solid oxide fuel cell stacks (IT-SOFC). The ratio of PVA to metal nitrates and the calcination temperature of the precursor were optimized for the process. The electrical conductivity and thermal expansion coefficient (TEC) of the synthesized LCN64 and its chemical compatibility with SUS 430 were also characterized. The results indicate that 1:4 is a proper ratio of PVA to metal nitrates for process control and safety management; and calcination of the precursor at temperatures above 650 °C leads to formation of single perovskite phase LCN64. The conductivity of fully sintered LCN64 is above 1150 S cm⁻¹ in the temperature range between 100 °C and 800 °C, which is higher than those of conventional contact materials La_1−xSr_xMnO₃ (LSM) and LaNi_yFe_1−yO₃ (LNF). The average TEC is 17.22 × 10⁻⁶ K⁻¹ at temperatures below 900 °C, which is higher than those of the metallic interconnect and cell components. Mn and Cr elements contained in SUS 430 migrated into the porous LCN64 layer at 800 °C without chemically forming resistive phases.