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Abstract: Anode-supported electrolyte composite membranes were prepared by a multilayer tape casting and co-sintering procedure. Nickel/yttria-stabilized zirconia (Ni/YSZ), nickel/scandia-stabilized zirconia (Ni/ScSZ) cermets, ScSZ, and Ce0.9Gd0.1O1.9 (CGO) were used as materials of anode substrate, anode functional layer, electrolyte and interlayer. After tape casting and dryness, the green tapes were co-sintered at 1350, 1400, and 1450 °C for 4 h in air. Then the LSCF-CGO composite cathode was deposited on the CGO surface by screen-printing and sintered at 1100 °C for 3 h. The performance of the anode-supported planar single SOFC was investigated in detail. In order to measure the AC impedance spectra, the symmetrical anode-supported cell design was used and also prepared by tape casting and co-sintering techniques. [Copyright &y& Elsevier]

Abstract: A novel direct carbon fuel cell is designed and fabricated using cathode-supported tubular solid oxide fuel cell technology, which makes the research and optimization of fuel electrode much easier. The maximum power density of a SO-DCFC (solid oxide direct carbon fuel cell) single cell is 172.7 and 91.1mWcm−2 at 900 and 850°C, respectively, with carbon as the fuel humidified nitrogen to initiate reforming reactions. Results show that the cathode supported tubular design may have future promise. [Copyright &y& Elsevier]

Abstract: In this paper, we model and analyze thermal focusing effect in the microchip lasers pumped by vertical-cavity surface-emitting lasers (VCSELs) for a special pump scheme, in which the microchip is axially connected with the VCSEL pump source without a gap between them to form a sort of ultra-compact monolithic micro-lasers. Thus, the thermal effects are related to twofold heating processes in the microchip. One is the common pump beam heating. The other is the heat flux diffusion from VCSEL to microchip through the contact interface between both, the latter leads to different thermo-optic characteristics from that generated only by the pump beam heating in the microchip. The temperature-, the stress- and the expansion-related phase variations and thus the thermal focusing properties of the microchip regarding the twofold heating processes are calculated and discussed for various pump power densities and temperatures of the VCSEL using analytical models. The results show that both heating processes in such a pump configuration can produce comparable thermal effects to each other. The influence of the heat transfer from the VCSEL to the microchip laser performance is discussed as well. [Copyright &y& Elsevier]

Abstract: The electrochemical performance of ESB [(Bi2O3)1− x (Er2O3) x ]–Ag composite material for IT-SOFC cathode was studied on the SSZ [(ZrO2)0.89(Sc2O3)0.1(CeO2)0.01] electrolyte. The influence of different ESB/Ag ratio and erbium-doped content on the performance of the composite cathode was investigated using AC impedance spectroscopy analysis. The investigation showed that there was a low polarization resistance (0.16 Ω cm2 to 0.50 Ω cm2 at temperatures from 750 °C to 650 °C) when the content of 3ESB [(Bi2O3)0.7(Er2O3)0.3] and Ag was equal in composite cathode. [Copyright &y& Elsevier]

Abstract: A Ni/scandia-stabilized zirconia (ScSZ) cermet anode was modified by coating with nano-sized gadolinium-doped ceria (GDC, Gd0.2Ce0.8O2) prepared using a simple combustion process within the pores of the anode for a solid oxide fuel cell (SOFC) running on methane fuel. X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed in the anode characterizations. Then, the short-term stability for the cells with the Ni/ScSZ and 2.0wt.%GDC-coated Ni/ScSZ anodes in 97%CH4/3%H2O at 700°C was checked over a relative long period of operation. Open circuit voltages (OCVs) increased from 1.098 to 1.179V, and power densities increased from 224 to 848mWcm−2, as the operating temperature of an SOFC with 2.0wt.%GDC-coated Ni/ScSZ anode was increased from 700 to 850°C in humidified methane. The coating of nano-sized Gd0.2Ce0.8O2 particle within the pores of the porous Ni/ScSZ anode significantly improved the performance of anode supported cells. Electrochemical impedance spectra (EIS) illustrated that the cell with Ni/ScSZ anode exhibited far greater impedances than the cell with 2.0wt.%GDC-coated Ni/ScSZ anode. Introduction of nano-sized GDC particles into the pores of porous Ni/ScSZ anode will result in a substantial increase in the ionic conductivity of the anode and increase the triple phase boundary region expanding the number of sites available for electrochemical activity. No significant degradation in performance has been observed after 84h of cell testing when 2.0wt.%GDC-coated Ni/ScSZ anode was exposed to 97%CH4/3%H2O at 700°C. Very little carbon was detected on the anodes, suggesting that carbon deposition was limited during cell operation. Consequently, the GDC coating on the pores of anode made it possible to have good stability for long-term operation due to low carbon deposition. [Copyright &y& Elsevier]