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Protonic ceramic ethane fuel cells fed by hydrocarbon fuels are demonstrated to be effective energy conversion devices. However, their practical application is impeded by a lack of anode materials combining excellent catalytic activity with good chemical stability and anti‐carbon deposition properties. In this work, in which Sr2Fe1.5Mo0.5O6‐δ (SFM) double perovskite oxide is used as the matrix framework, catalytic activity toward H2 and C2H6 oxidation is systematically investigated using Ba‐doping. It is found that the concentration of the oxygen vacancy is gradually improved with increased Ba content to significantly enhance catalytic activity toward H2 and C2H6 oxidation. From the series studied, Ba0.6Sr1.4Fe1.5Mo0.5O6‐δ exhibits the highest catalytic activity, while the power densities of the electrolyte‐supported Ba0.6SFM/BaCe0.7Zr0.1Y0.2O3‐δ (BCZY)/La0.58Sr0.4Co0.2Fe0.8O3‐δ (LSCF)‐Sm0.2Ce0.8O2‐δ (SDC) single cell reach 205 and 138 mW cm–2 at 750°C in H2 and C2H6, respectively. The ethane conversion rate of the experimental cell is shown to reach 38.4%, while simultaneously maintaining ethylene selectivity at 95%. Furthermore, the single cell exhibits no significant attenuation during stable operation for 20 h, as well as demonstrating excellent anti‐coking performance. The proposed results suggest that Ba0.6Sr1.4Fe1.5Mo0.5O6‐δ represents a promising anode material for efficient hydrocarbon‐related electrochemical conversion to realize the coproduction of ethylene and power in protonic ceramic ethane fuel cells. [ABSTRACT FROM AUTHOR]

A La 0.5 Sr 0.5 Fe 0.9 Mo 0.1 O 3-δ -CeO 2 (LSFM-CeO 2) composite was prepared by impregnating CeO 2 into porous La 0.5 Sr 0.5 Fe 0.9 Mo 0.1 O 3-δ perovskite and was used as an anode material for proton-conducting solid oxide fuel cells (SOFCs). The maximum power densities of the BaZr 0.1 Ce 0.7 Y 0.2 O 3-δ (BZCY) electrolyte-supported single cell with LSFM-CeO 2 as the anode reached 291 mW cm−2 and 190 mW cm−2 in hydrogen and ethane fuel at 750 °C, respectively, which are significantly higher than those of a single cell with only LSFM as the anode. Additionally, the ethylene selectivity and ethylene yield from ethane for the fuel cell at 750 °C were as high as 93.4% and 37.1%, respectively. The single cell also showed negligible degradation in performance and no carbon deposition during continuous operation for 22 h under an ethane fuel atmosphere. The improved electrochemical performance due to the impregnation of CeO 2 can be a result of enhanced electronic and ionic conductivity, abundant active sites, and a broad three-phase interface in the resultant composite anode. The LSFM-CeO 2 composite is believed to be a promising anode material for proton-conducting SOFCs for co-producing electricity and high-value chemicals from hydrocarbon fuels. [ABSTRACT FROM AUTHOR]

Developing low temperature solid oxide fuel cells has been a prerequisite for commercialization. In response to this issue, a novel strategy for the directional construction of Ni/SDC anodes via magnetic field to achieve better polarization than the traditional Ni/SDC anodes in low operating temperature range (≤600°C) is exploited. In the condition of Ni and SDC particles lining up end to end to construct Ni/SDC anodes (Ni/SDC-B T), the polarization resistance (R p) of the remodeled Ni/SDC-B T in humidified H 2 are 0.263, 0.088 and 0.037 Ω cm2 at 500, 550 and 600°C, respectively. Furthermore, the optimization mechanism is proposed via the microstructure model. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Symmetrical solid oxide fuel cell (SOFC) adopting the same material at both electrodes is potentially capable of promoting thermomechanical compatibility between near components and lowering stack costs. In this paper, MnCr 2 O 4 –Gd 0.1 Ce 0.9 O 2-δ (MCO-GDC) composite electrodes prepared by co-infiltration method for symmetrical electrolyte supported and anode supported solid oxide fuel cells are evaluated at a temperature range of 650–800 °C in wet (3% H 2 O) hydrogen and air atmospheres. Without any alkaline earth elements and cobalt, the co-infiltrated MCO-GDC composite electrode shows excellent activity for oxygen reduction reaction but mediocre activity for hydrogen oxidation reaction. With MCO-GDC as the cathode, the Ni-YSZ (Y 2 O 3 stabilized ZrO 2) anode supported asymmetrical cell demonstrates a peak power density of 665 mW cm−2 at 800 °C. The above results suggest MCO-GDC is a promising candidate cathode material for solid oxide fuel cells. • MnCr 2 O 4 is chemically stable at typical dual atmospheres of SOFC. • Co-infiltration promotes the performance of MnCr 2 O 4 -GDC composite electrode. • MnCr 2 O 4 -GDC exhibits reasonable activity as cathode. • Anode supported cell achieves a peak power density of 665 mW cm−2 at 800 °C. [ABSTRACT FROM AUTHOR]

A layered Mo doped Pr 0.5 Ba 0.5 MnO 3−δ (Mo-PBMO) double perovskite oxide was prepared by a modified sol–gel method and the properties of the fabricated material are characterized by various technologies. The results of X-ray diffraction (XRD), H 2 -temperature programmed reduction (H 2 -TPR), NH 3 -temperature programmed desorption (NH 3 -TPD), and thermogravimetric analysis (TGA) demonstrate that the treatment in reducing atmosphere at high temperature lead to a significant phase transformation of the material to a single cubic phase as well as with the Mo in multiple oxidized states. Such character leads to the production of large amount of oxygen deficiency with facilitated oxygen diffusion. The electrochemical performance tests of half-cell and single cell SOFCs exhibit the promoted effect of Mo on catalytic activity for the oxidation of H 2 and CH 4 , indicating that Mo-PBMO could serve as an anode material candidate for SOFCs. [ABSTRACT FROM AUTHOR]

Active anodes were fabricated via wet chemical impregnation of optimized amount of La 0.4 Sr 0.6 TiO 3 (L4ST) into La 0.4 Ce 0.6 O 1.8 (LDC) pre-infiltrated porous yttria-stabilized zirconia (YSZ) matrix. Impregnations of 10 wt% LDC with 16 wt% L4ST significantly improved the performance of the fuel cell from 48 mW cm −2 for pure L4ST to 161 mW cm −2 for LDC–L4ST at 900 °C in H 2 . The contribution of the pre-loaded LDC to this improvement was investigated using electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM) as well as transmission electron microscopy (TEM). The measurement results indicated that pre-infiltrated LDC increased the activity of the anode more effectively by decreasing the total polarization resistance of the cell from 3.3 Ω cm 2 to 1.0 Ω cm 2 in humidified H 2 at 900 °C. More importantly, the LDC nano-deposits (<20 nm) behaved as an effective “adhesive” that substantially enhanced the wettability of L4ST on YSZ matrix, resulting in finer and more uniform structure of L4ST infiltrates. The LDC–L4ST cells also demonstrated significantly improved performances in 0.5% H 2 S–H 2 and 0.5% H 2 S–CH 4 with higher stability than cells with pure L4ST anode. [ABSTRACT FROM AUTHOR]

Ethane can be electrochemically dehydrogenated and converted into electric energy via protonic ceramic fuel cells to obtain highly selective chemical ethylene without producing carbon oxides. This novel conversion path relies on a highly catalytically active anode for promote the cracking of ethane. In responding to this requirement, a previously characterized anode material (La 0.6 Sr 0.4) 0.95 Fe 0.9 Mo 0.1 O 3-δ (LSFM) is modified by doping with active metals (Ni and Co) at the B-site of a perovskite structure. The (La 0.6 Sr 0.4) 0.95 Fe 0.7 Ni 0.2 Mo 0.1 O 3-δ (LSFNM), (La 0.6 Sr 0.4) 0.95 Fe 0.7 Co 0.2 Mo 0.1 O 3-δ (LSFCM) and (La 0.6 Sr 0.4) 0.95 Fe 0.7 Co 0.1 Ni 0.1 Mo 0.1 O 3-δ (LSFCNM) electrode materials are synthesized by the combustion method. The subsequent in situ exsolution of the FeNi, CoFe and NiCoFe alloy nanoparticles in a reducing atmosphere improves the catalytic performance of the resultant electrodes. The obtained data show that the maximum power densities of single cells constructed using LSFCNM as an anode material at 750 °C reach 328 mW cm−2 and 258 mW cm−2 in H 2 and C 2 H 6 , respectively. Meanwhile, the ethane conversion process yields ∼44% under a constant current. The significantly higher performance of these cells than that achieved with single cells using LSFNM and LSFCM as anode materials, respectively, indicate that the NiCoFe ternary alloy offers better synergistic catalytic activity than that of the CoFe and FeNi binary alloys. [Display omitted] •In situ precipitation ternary alloys by doping active metals Ni and Co elements. •The segregation of nanoparticles obtains abundant active oxygen vacancies. •The thermal catalytic and electrochemical properties are significantly improved. •Ethylene and electricity can be coproduced in ethane-fueled protonic ceramic fuel cells. [ABSTRACT FROM AUTHOR]

Anode materials with excellent catalytic activity, good stability, and enhanced tolerance to carbon deposition are highly desired for solid oxide fuel cells (SOFCs). Herein, CoFe (CF) nanoalloy catalysts are homogeneously in-situ embedded on Sr 3 FeMoO 7 (RP-SFM) efficient electrically conductive perovskite matrix through reduction of Sr 2 FeMo 2/3 Co 1/3 O 6−δ precursor. The particle size of CoFe alloy is in the range of 10–50 nm, and the electrical conductivity enhances from about 8 to 17 S cm−1 to 49-63 S cm−1 after Sr 2 FeMo 2/3 Co 1/3 O 6−δ reduction. The maximum power density of SOFCs with the RP-SFM@CF-SDC(Sm 0.2 Ce 0 · 8 O 1.9) composite anode in H 2 fuel reaches to 2.12 W cm−2 at 850 °C, which is about 1.4 times than that of the SOFCs with traditional Ni-SDC anode. Moreover, the RP-SFM@CF-SDC anodes also demonstrate excellent resistance to carbon deposition and high power density when C 3 H 8 hydrocarbon is used as fuel. The improved catalytic activity results from the efficient electronic/ion conductive paths, abundant CoFe active sites, together with the enlarged trip phase boundaries (TPBs). Image 1 • CoFe(CF) nanoalloy are homogeneously embedded on the layered perovskite RP-SFM. • RP-SFM@CF anode exhibits excellent catalytic activity and good structural stability. • RP-SFM@CF-SDC anode exhibits higher electrochemical performance than Ni-SDC. • The improved performance results from the abundant CoFe active sites and TPBs. [ABSTRACT FROM AUTHOR]