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Solid-oxide fuel cells (SOFCs) offer great promise for producing electricity using a wide variety of fuels such as natural gas, coal gas and gasified carbonaceous solids; however, conventional nickel-based anodes face great challenges due to contaminants in readily available fuels, especially sulphur-containing compounds. Thus, the development of new anode materials that can suppress sulphur poisoning is crucial to the realization of fuel-flexible and cost-effective SOFCs. In this work, La0.1Sr1.9Fe1.4Ni0.1Mo0.5O6–δ (LSFNM) and Pr0.1Sr1.9Fe1.4Ni0.1Mo0.5O6–δ (PSFNM) materials have been synthesized using a sol-gel method in air and investigated as anode materials for SOFCs. Metallic nanoparticle-decorated ceramic anodes were obtained by the reduction of LSFNM and PSFNM in H2 at 850°C, forming a Ruddlesden–Popper oxide with exsolved FeNi3 bimetallic nanoparticles. The electrochemical performance of the Sr2Fe1.4Ni0.1Mo0.5O6–δ ceramic anode was greatly enhanced by La doping of A-sites, resulting in a 44% decrease in the polarization resistance in reducing atmosphere. The maximum power densities of Sr- and Mg-doped LaGaO3 (LSGM) (300 μm) electrolyte-supported single cells with LSFNM as the anode reached 1.371 W cm −2 in H2 and 1.306 W cm–2 in 50 ppm H2S–H2 at 850°C. Meanwhile, PSFNM showed improved sulphur tolerance, which could be fully recovered after six cycles from H2 to 50 ppm H2S–H2 operation. This study indicates that LSFNM and PSFNM are promising high-performance anodes for SOFCs. [ABSTRACT FROM AUTHOR]

The turn-off capability test for the single cell of power devices is of great significance to both the safe operation assurance and the destruction mechanism research. However, with present techniques, the device under test is supposed to be destroyed once the turn-off fault occurs. In this article, a robust nondestructive test scheme based on the multistage anode voltage detection for 4500 V single-cell turn-off capability of press-packed devices is proposed. Based on the proposed scheme, a single cell of IGCT is tested until a fault occurs. The result proves that a total bypass time is less than 100 ns for the 2200 V/5 A turn-off fault, and thus, the aim of nondestructive tests can be achieved with the proposed method. [ABSTRACT FROM AUTHOR]

Abstract: Low-temperature solid oxide fuel cells (SOFCs) operated at a temperature of 500 °C and below are developed by modifying the microstructures of single cells consisting of Ni-cermet anodes, doped ceria electrolytes and strontium-doped samaria cobaltite cathodes. The cell microstructure is optimized by varying the starting powder firing temperature, so that the doped ceria electrolytes have a high sinterability, reducing the spin-coating cycles to decrease the electrolyte thickness to approximately 9 μm, adopting a two-step sintering process so that the electrolytes consist of small grains and have a high density; while the anodes are composed of small particles and have high porosity. In particular, the two-step sintering process depresses the co-firing temperature, thus enhancing the electrolyte conductivity and reducing the electrode polarization resistance. Outstanding performance with peak power density of 476, 319, and 189 mW cm−2 at 500, 450, and 400 °C is achieved with a typical single cell comprising a 9-μm-thick Sm0.2Ce0.8O1.9 (SDC) electrolyte, a Ni-SDC porous anode, and a Sm0.5Sr0.5CoO3−δ -Sm0.2Ce0.8O1.9 (SSC-SDC) composite cathode. A durability test over 110 h maintained a power density of approximately 150 mW cm−2 at 400 °C, suggesting optimization of the microstructure has promise for enhancing the performance of low-temperature SOFCs. [ABSTRACT FROM AUTHOR]

Abstract: Sr2Fe1.5Mo0.5O6 (SFMO) shows good chemical compatibility with NiO under 1000°C. By dispersing a small amount of Ni (~2wt%) into the SFMO anode, the performance of the fuel cells with La0.8Sr0.2Ga0.83Mg0.17O3 (LSGM) electrolyte and La0.6Sr0.4Co0.2Fe0.8O3 (LSCF) cathode is dramatically improved. With ambient air as the oxidant, the cell peak power density reaches 1.134Wcm−2 in wet H2 (3vol% H2O) and 0.663Wcm−2 in wet CH4 (3vol% H2O) at 800°C. Stable cell performance is achieved when operating the cell with CH4 as fuel at 0.7V, indicating no significant carbon formation on the Ni-modified SFMO anode. Considering the simple anode fabrication procedure and the relatively low cost of the anode materials, Ni modified SFMO ceramic anode shows great promise for direct-methane solid oxide fuel cells. [Copyright &y& Elsevier]

This image represENts a hierarchically porous Sr2Fe1.5Mo0.5O6−δ–Gd0.1Ce0.9O1.95 (SFM ‐ GDC) ceramic anode ‐ supported solid ‐ oxide fuel cell with a GDC electrolyte film. The nanocatalyst can precipitate from the parENt SFM phase upon reduction and can react with sulfur species in the fuel to form needle ‐ like nanosulfides with a gradiENt distribution (i.e. less the nanosulfide closer to the electrolyte), demonstrating excellENt sulfur tolerance of the SFM ‐ GDC ceramic anode, as shown by M. Han, F. ChEN et   al. on p.   672. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cells (SOFCs) based on a thin La 0.8 Sr 0.2 Ga 0.8 Mg 0.2 O 3−δ (LSGM) electrolyte membrane supported by a nickel-based anode often suffers from undesirable reaction/diffusion between the Ni anode and the LSGM during high-temperature co-firing. In this study, a high performance intermediate-temperature SOFC is fabricated by depositing thin LSGM electrolyte membranes on a LSGM backbone of unique architecture coated with nano-sized Ni and Gd 0.1 Ce 0.9 O 2−δ (GDC) particles via a combination of freeze-drying tape-casting, slurry drop-coating, and solution infiltration. The thickness of the dense LSGM electrolyte membranes is ∼30 μm while the undesirable reaction/diffusion between Ni and LSGM are effectively hindered because of the relatively low firing temperature, as confirmed by XRD analysis. Single cells show peak power densities of 1.61 W cm −2 at 700 °C and 0.52 W cm −2 at 600 °C using 3 vol% humidified H 2 as fuel and ambient air as oxidant. The cell performance is very stable for 115 h at a constant current density of 0.303 A cm −2 at 600 °C. [ABSTRACT FROM AUTHOR]

Protonic ceramic electrochemical cells (PCECs) have the potential in reducing the energy input and carbon emissions in ethylene production from ethane dehydrogenation. The performance of conventional perovskite-based anode materials for ethane conversion in PCECs is limited by their low active surface area and proneness to coke deposition. In this work, for the first time, we demonstrate the use of aligned carbon nanotube forests (CNTFs) as a novel anode material for an ethane fueled PCEC to co-produce ethylene and electricity. The CNTF electrode was grown on the electrolyte by the chemical vapor deposition (CVD) method. Highly dispersed iron carbide nanoparticles are formed in situ on the CNTFs during the CVD process, acting as highly active catalysts for ethane dehydrogenation. The novel PCECs show superior catalytic and electrochemical performances to that using conventional perovskite-based anodes. The cell also exhibits excellent durability and anti-coking abilities within 100 h test. This work showcases the promising application of nanostructured carbon, a new class of non-perovskite materials, as the multifunctional electrode materials for PCECs. [Display omitted] • CNTF can be integrated into PCEC as electrode and catalyst support by CVD method. • CNTF is a promising non-perovskite candidate electrode material for PCEC. • CNTF shows superior electrochemical and catalytic performance than SFM. • Carburized Fe species on CNTF are the active species for EDH reaction. [ABSTRACT FROM AUTHOR]

Abstract: A two-dimensional isothermal mathematical model is developed for an anode-supported solid oxide fuel cell using samaria doped-ceria as electrolyte. This model takes into account species transfer and electrochemical reaction processes for cell operating between 500°C and 600°C. In this model, it is assumed that the electrochemical reactions take place not only at the electrolyte/electrode boundaries, but also throughout the electrodes. The model is validated with the experimental data. The geometry and operating parametric analyses are conducted to understand the coupled electrochemical reaction and species transfer phenomena. The results indicate that the rate of leakage current increases with the increase either in cell operating voltages, or in cell operating temperatures. It is also found that higher hydrogen concentration in the fuel stream results in larger leakage current. Further, the current efficiency decreases with the increase either in cell active areas, or in cell operating temperatures. [Copyright &y& Elsevier]

The microstructure of the anode in anode-supported solid oxide fuel cells has significant influence on the cell performance. In this work, microtubular Ni-yttria stabilized zircona (Zr 0.8 Y 0.2 O 2 , YSZ) anode support has been prepared by the phase inversion method. Different compositions of non-solvent have been used for the fabrication of the Ni-YSZ anode support, and the correlation between non-solvent composition and characteristics of the microstructure of the anode support has been investigated. The presence of ethanol or isopropanol in the non-solvent can inhibit the growth of the finger-like pores in the anode support. With the increase of the concentration of ethanol or isopropanol in the non-solvent, a thin dense layer can be observed on the top of the prepared tubular anode support. In addition, the mechanism of pore formation is explained based on the inter-diffusivity between the solvent and the non-solvent. The prepared microtubular solid oxide fuel cells (MT-SOFCs) have been tested, and the influence of the anode microstructure on the cell electrochemical performance is analyzed based on a polarization model. • Different non-solvent was used for SOFC fabrication via phase inversion method. • Pore formation was explained by inter-diffusivity between solvent and non-solvent. • Effect of anode microstructure on performance was analyzed by a polarization model. [ABSTRACT FROM AUTHOR]

Perovskite oxide Sr 2 Fe 1.3 Mo 0.5 Ni 0.2 O 6-σ (SFMNi) impregnated on the scaffold of hierarchically oriented yttria-stabilized zirconia (YSZ) with open, straight pores (SFMNi@YSZ), that could transformed into in-situ exsolved Ni–Fe alloy nanoparticles structured SFMNi@YSZ (NiFe@SFMNi@YSZ) electrode, have been prepared and utilized for robust direct propane-fueled solid oxide fuel cell (SOFC). The hierarchically oriented open, straight pores can not only significantly facilitate the introduction of uniformly distributed SFMNi nano-catalyst network via the ion-impregnation method, but also greatly enhance the gas diffusion process in the porous electrode, thus greatly minimizing even eliminating the concentration resistance. The impregnated SFMNi nano-catalysts, especially the in-situ exsolved Ni–Fe alloy nano-catalysts, could effectively activate the fuel gas oxidation reaction in the anode, thereby drastically decreasing the activation resistance and enhancing the cell performance. The full ceramic electrode can efficiently avoid electrode aggregation and carbon coking, leading to excellent stability towards propane oxidation. Our findings indicate that NiFe@SFMNi@YSZ full ceramic electrode with hierarchically oriented open, straight pores offers a great promise for direct hydrocarbon SOFC. [Display omitted] • A novel hierarchically oriented electrode support with open, straight pores is prepared by the PITC method. • Contact angle and gas permeability results indicate the significantly lowered difficulty of nano-catalysts infiltration. • NiFe@SFMNi@YSZ electrode is fabricated by the combined PITC, ion impregnation, and in-situ exsolution technique. • NiFe@SFMNi@YSZ electrode exhibits good performance and stability when fed with C 3 H 8 fuel. • NiFe@SFMNi@YSZ electrode can simultaneously lower the concentration and activation resistance. [ABSTRACT FROM AUTHOR]

Influence of the air-gap, the distance from the tube-in-orifice spinneret to the upper surface of the external coagulant bath during the extrusion/phase-inversion process, on the microstructure of nickel – yttria-stabilized zirconia (Ni–YSZ) hollow fibers has been systematically studied. When the air-gap is 0 cm, the obtained Ni–YSZ hollow fiber has a sandwich microstructure. However, when the air-gap is increased to 15 cm, a bi-layer Ni–YSZ hollow fiber consisting of a thin layer with small pores and a thick support with highly porous fingerlike macrovoids has been achieved. The output power density of microtubular solid oxide fuel cells (MT-SOFCs) with a cell configuration of Ni–YSZ/YSZ/YSZ–LSM increases from 594 mW cm −2 for the cells with the Ni–YSZ anode of sandwich microstructure to 832 mW cm −2 for the cells with the Ni–YSZ anode of bi-layer microstructure at 750 °C, implying that to achieve the same output power density, the weight of the cells with the bi-layer anode support can be reduced to 41.5% compared with that of the cells with the sandwich anode support. Thermal-cycling test shows no obvious degradation on the open-circuit-voltage (OCV), indicating that the MT-SOFCs have robust resistance to thermal cycling. [ABSTRACT FROM AUTHOR]

Anode-supported micro-tubular solid oxide fuel cells (MT-SOFCs) have been fabricated by phase inversion method. For the anode support preparation, N-methyl-2-pyrrolidone (NMP), polyethersulfone (PESf) and poly ethylene glycol (PEG) were applied as solvent, polymer binder and additive, respectively. The effect of molecular weight and amount of PEG additive on the thermodynamics of the casting solutions was characterized by measuring the coagulation value. Viscosity of the casting slurries was also measured and the influence of PEG additive on viscosity was studied and discussed. The presence of PEG in the casting slurry can significantly influence the final anode support microstructure. Based on the microstructure result and the measured gas permeation value, two anode supports were selected for cell fabrication. For cell with the anode support fabricated using slurry with PEG additive, a maximum cell power density of 704 mW cm −2 is obtained at 750 °C with humidified hydrogen as fuel and ambient air as oxidant; cell fabricated without any PEG additive shows the peak cell power density of 331 mW cm −2 . The relationship between anode microstructure and cell performance was discussed. [ABSTRACT FROM AUTHOR]

Abstract: The perovskite material Pr0.4Sr0.6Co0.2Fe0.7Nb0.1O3−δ was used as an anode in direct propane fueled solid oxide fuel cells (SOFCs). After exposure of the initial single phase Pr0.4Sr0.6Co0.2Fe0.7Nb0.1O3−δ to a reducing atmosphere at 900 °C, it transformed to a two-phase system with nano-particles of a Co–Fe bimetallic alloy uniformly distributed on a Ruddlesden–Popper ceramic phase. High cell power output and good stability were obtained using propane as the fuel and ambient air as the oxidant. Due to the catalytic effect of the Co–Fe bimetallic alloy in the SOFC operating conditions, macromolecular compounds of polycyclic aromatic hydrocarbons (PAHs) were generated as by-products in the exhaust stream of the anode. This novel anode system successfully demonstrated the co-generation of electricity and high value end use chemicals from direct hydrocarbon fueled SOFC systems. [Copyright &y& Elsevier]

Abstract: Solid oxide fuel cell (SOFC) has experienced a growing interest in the last few decades because of generating energy more efficiently than the conventional combustion of fossil fuels. By using the same material as anode and cathode of SOFC (symmetric fuel cell), the production of reliable and repeatable cells would be simpler. In this work, La0.4Sr0.6Co0.2Fe0.7Nb0.1O3−δ (LSCFN) perovskite has been prepared and evaluated as both cathode and anode material of symmetric fuel cell. The results of symmetric fuel cell show that a maximum peak power density of 500 mW cm−2 has been achieved and the total electrode polarization resistances of the cell is only 0.22 Ω cm2 at 850 °C which is much lower than that of typical symmetric fuel cell with La0.75Sr0.25Cr0.5Mn0.5O3−δ as electrode material. All of these results indicate that LSCFN can potentially be a promising candidate for the electrode material of symmetric fuel cell. [Copyright &y& Elsevier]

Abstract: Anode supported intermediate temperature micro-tubular solid oxide fuel cells (MT-SOFCs) with the cell configuration of Ni-Sc2O3 stabilized ZrO2 (ScSZ)/ScSZ/(La0.75Sr0.25)0.95MnO3 (LSM)-Sm0.2Ce0.8O1.9 (SDC)-ScSZ have been fabricated by a combination of phase-inversion, dip-coating, co-sintering and impregnation method. Cross-sectional SEM images of the fabricated MT-SOFC reveal that the dense ScSZ electrolyte and porous ScSZ backbone in the anode and cathode formed together, and the stability test demonstrates that the fabricated MT-SOFCs have robust resistance to thermal cycling. Maximum power densities of 0.29, 0.40 and 0.52Wcm−2 have been achieved at 550, 600 and 650°C, respectively. The results indicate that the fabricated MT-SOFC has potential applications for portable power needs. [Copyright &y& Elsevier]

Abstract: The future commercialization and application of solid oxide fuel cell (SOFC) technologies requires the development of novel anode materials with excellent performance and stability at intermediate-temperatures with various fuels including hydrogen, syngas and particularly hydrocarbons. Whether by modifying the state-of-the-art Ni based anodes, or through exploring alternative metal cermet or ceramic based materials, wet impregnation/infiltration is shown to be one of the most effective approaches for both cell fabrication and performance optimization. This paper reviews most of the progress reported in the literature committed to the fabrication and optimization of SOFC anodes by wet impregnation for low temperature and/or hydrocarbon operation. The optimization of traditional nickel based anodes by adding excellent catalyst, the replacement of nickel by other inert metal or ceramic species, and some metal supported designs with impregnated catalyst are all presented and discussed, mainly focusing on the cell performance, redox and thermal stability, long-term reliability, carbon and sulfur tolerance of the anodes. [Copyright &y& Elsevier]

Abstract: Anode-supported solid oxide fuel cells (SOFCs) based on complex-perovskite structured Ba3Ca1.18Nb1.82O9−δ (BCN18) proton-conducting electrolyte membranes have been successfully fabricated by a novel two-step co-sintering method. BCN18 has been reported to have excellent chemical stability against H2O and CO2, but is relatively difficult to densify. In this study, dense BCN18 electrolyte membranes with fine grain size have been obtained by a novel two-step co-sintering method at a relatively low sintering temperature of 1,300 °C, compared to the typical high sintering temperature of 1,550 °C. Furthermore, the Ni–BaZr0.1Ce0.7Y0.1Yb0.1O3−δ anode obtained by the novel two-step co-sintering method was composed of small particles with high porosity which is advantageous for electrode performance. Single fuel cells using BCN18 as the electrolyte, Ni–BaZr0.1Ce0.7Y0.1Yb0.1O3−δ as anode and Ba0.9Co0.7Fe0.2Nb0.1O3−δ as cathode demonstrated a power density of 106 mW cm−2 at 750 °C, the best fuel cell performance ever reported for the BCN18 electrolyte. These results suggest that the two-step co-sintering method is a promising method to optimize the microstructure, and combined with proper electrodes, enhanced performance of anode-supported SOFCs using BCN18 proton-conducting electrolyte can be obtained. [Copyright &y& Elsevier]

Abstract: Sr2Fe1.5Mo0.5O6−δ (SFM) was prepared using a microwave-assisted combustion synthesis method. Rietveld refinement of powder X-ray diffraction data reveals that SFM crystallizes in the simple cubic perovskite structure with iron and molybdenum disordered on the B-site. No structure transition was observed by variable temperature powder X-ray diffraction measurements in the temperature range of 25–800°C. XPS results show that the iron and molybdenum valences change with an increase in temperature, where the mixed oxidation states of both iron and molybdenum are believed to be responsible for the increase in the electrical conductivity with increasing temperature. SFM exhibits excellent redox stability and has been used as both anode and cathode for solid oxide fuel cells. Presence of sulfur species in the fuel or direct utilization of hydrocarbon fuel can result in loss of activity, however, as shown in this paper, the anode performance can be regenerated from sulfur poisoning or coking by treating the anode in an oxidizing atmosphere. Thus, SFM can be used as a regenerating anode for direct oxidation of sulfur-containing hydrocarbon fuels. [Copyright &y& Elsevier]

Abstract: Anode-supported micro-tubular solid oxide fuel cells (SOFCs) based on a proton and oxide ion mixed conductor electrolyte, BaZr0.1Ce0.7Y0.1Yb0.1O3−δ (BZCYYb), have been fabricated using phase inversion and dip-coating techniques with a co-firing process. The single cell is composed of NiO–BZCYYb anode, BZCYYb electrolyte and La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF)–BZCYYb cathode. Maximum power densities of 0.08, 0.15, and 0.26Wcm−2 have been obtained at 500, 550 and 600°C, respectively, using H2 as fuel and ambient air as oxidant. [Copyright &y& Elsevier]

Abstract: Sr2Fe4/3Mo2/3O6 has been synthesized by a combustion method in air. It shows a single cubic perovskite structure after being reduced in wet H2 at 800°C and demonstrates a metallic conducting behavior in reducing atmospheres at mediate temperatures. Its conductivity value at 800°C in wet H2 (3% H2O) is about 16Scm−1. This material exhibits remarkable electrochemical activity and stability in H2. Without a ceria interlayer, maximum power density (P max) of 547mWcm−2 is achieved at 800°C with wet H2 (3% H2O) as fuel and ambient air as oxidant in the single cell with the configuration of Sr2Fe4/3Mo2/3O6|La0.8Sr0.2Ga0.83Mg0.17O3 (LSGM)| La0.6Sr0.4Co0.2Fe0.8O3 (LSCF). The P max even increases to 595mWcm−2 when the cell is operated at a constant current load at 800°C for additional 15h. This anode material also shows carbon resistance and sulfur tolerance. The P max is about 130mWcm−2 in wet CH4 (3% H2O) and 472mWcm−2 in H2 with 100ppm H2S. The cell performance can be effectively recovered after changing the fuel gas back to H2. [ABSTRACT FROM AUTHOR]

Abstract: Perovskite Sr2Fe1.5Mo0.5O6−δ (SFM) has been successfully prepared by a microwave-assisted combustion method in air and employed as both anode and cathode in symmetrical solid oxide electrolysis cells (SOECs) for hydrogen production for the first time in this work. Influence of cell operating temperature, absolute humidity (AH) as well as applied direct current (DC) on the impedance of single cells with the configuration of SFM|La0.9Sr0.1Ga0.8Mg0.2O3 (LSGM)|SFM has been evaluated. Under open circuit conditions and 60 vol.% AH, the cell polarization resistance, R P is as low as 0.26 Ω cm2 at 900 °C. An electrolysis current of 0.88 A cm−2 and a hydrogen production rate as high as 380 mL cm−2 h have been achieved at 900 °C with an electrolysis voltage of 1.3 V and 60 vol.% AH. Further, the cell has demonstrated good stability in the long-term steam electrolysis test. The results showed that the cell electrolysis performance was even better than that of the reported strontium doped lanthanum manganite (LSM) – yttria stabilized zirconia (YSZ)|YSZ|Ni–YSZ cell, indicating that SFM could be a very promising electrode material for the practical application of SOEC technology. [ABSTRACT FROM AUTHOR]

In symmetrical solid oxide fuel cells, comprehensively understanding the elementary reaction processes and the polarization behaviors of redox-stable electrode materials is critical for further optimization of the electrode performance. In this work, a systematical and practical approach, based on electrochemical impedance spectroscopy technology, is applied to identify the rate-limiting elementary reactions of the redox-stable electrodes. The feasibility of this proposed method is demonstrated in symmetrical solid oxide fuel cells with Sr 2 Fe 1.5 Mo 0.5 O 6-σ -Ce 0.9 Gd 0.1 O 1.95 as electrodes. Based on the characteristic frequency ranges and the experimental results tested under various fuel gas components, operating temperatures, and discharge current densities, the rate-limiting steps of the cathode are associated with the formation of adsorbed oxygen ions and the combination of oxygen ions and oxygen vacancies, while the rate-limiting steps of the anode are ascribed to the hydrogen dissociated adsorption and the steam desorption processes. This experimental and analysis framework can be straightforwardly extended to other electrode materials to unravel their electrochemical performance in detail. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract: La0.6Sr1.4MnO4 (LSMO4) layered perovskite with K2NiF4 structure was prepared and evaluated as anode material for La0.8Sr0.2Ga0.83Mg0.17O3− δ (LSGM) electrolyte supported intermediate temperature solid oxide fuel cells (IT-SOFCs). X-ray diffraction results show that LSMO4 is redox stability. Thermal expansion coefficient of LSMO4 is close to that of LSGM electrolyte. By adopting LSMO4 as anode and La0.6Sr0.4Co0.8Fe0.2O3 (LSCF) as cathode, maxium power densities of 146.6, 110.9mWcm−2 with H2 fuel at 850, 800°C and 47.3mWcm−2 with CH4 fuel at 800°C were obtained, respectively. Further, the cell demonstrated a reasonably stable performance under 180mAcm−2 for over 40h with H2 fuel at 800°C. [Copyright &y& Elsevier]

Abstract: Cermet anodes composed of Ni and Dy2O3 have been applied as anode for intermediate-temperature solid oxide fuel cells. Although the oxide ion conductivity of Dy2O3 is negligible compared to that of doped ceria (DCO), Ni–Dy2O3 cermet anodes have displayed very high performance comparable to that of the commonly used Ni–SDC cermet anode. Temperature programmed reduction study suggests that the catalytic activity of the Ni–Dy2O3 cermet might be originated from the hydrogen adsorption ability on the Dy2O3 surface, promoting hydrogen spillover process, and consequently enhancing the electrochemical oxidation of the fuel. Further, the electrochemical catalytic activity of Au-based cermet anode confirms that hydrogen adsorption capability is as important as oxygen-ion conductivity for the ceramic component in a cermet anode. [Copyright &y& Elsevier]

Abstract: Cu1.3Mn1.7O4 spinel oxide has been synthesized and characterized as anode internal reforming layer for Ni–SDC anode-supported solid oxide fuel cells (SOFCs) directly operating on methane fuel. XRD and Cu mapping image results of Cu1.3Mn1.7O4 oxide after in-situ reduction by methane show that a highly dispersed nano-Cu metal network has been obtained. By adopting Cu1.3Mn1.7O4 as an internal reforming layer, the cell demonstrated maximum power densities of 242 and 311mWcm−2 at 650 and 700°C, respectively using methane as fuel and ambient air as oxidant. More importantly, Cu1.3Mn1.7O4 internal reforming layer has significantly improved the cell performance stability. The cell with the Cu1.3Mn1.7O4 internal reforming layer has demonstrated reasonably stable performance while the cell without it degraded very rapidly. [ABSTRACT FROM AUTHOR]