排序方式: 共有63条查询结果,搜索用时 62 毫秒
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Tim Van Gestel Feng Han Doris Sebold Hans Peter Buchkremer Detlev St?ver 《Microsystem Technologies》2011,17(2):233-242
A solid oxide fuel cell (SOFC) with a thin-film yttria-stabilized zirconia (YSZ) electrolyte was developed and tested. This
novel SOFC shows a similar multilayer set-up as other current anode-supported SOFCs and is composed of a Ni/8YSZ anode, a
gas-tight 8YSZ electrolyte layer, a dense Sr-diffusion barrier layer and a LSCF cathode. To increase the power density and
lower the SOFC operating temperature, the thickness of the electrolyte layer was reduced from around 10 μm in current cells
to 1 μm, using a nanoparticle deposition method. By using the novel 1 μm electrolyte layer, the current density of our SOFC
progressed to 2.7, 2.1 and 1.6 A/cm2 at operation temperatures of 800, 700 and 650°C, respectively, and out-performs all similar cells reported to date in the
literature. An important consideration is also that cost-effective dip-coating and spin-coating methods are applied for the
fabrication of the thin-film electrolyte. Processing of 1 μm layers on the very porous anode substrate material was initially
experienced as very difficult and therefore 8YSZ nanoparticle coatings were developed and optimized on porous 8YSZ model substrates
and transferred afterwards to regular anode substrates. In this paper, the preparation of the novel SOFC is shown and its
morphology is illustrated with high resolution SEM pictures. Further, the performance in a standard SOFC test is demonstrated. 相似文献
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Co, Co–Mn (67:33 at.%) and Co–Cu (67:33 at.%) coatings were fabricated using magnetron sputtering on two kinds of ferritic stainless steels (Crofer22APU and F17TNb) in order to form spinel protective coatings on metallic interconnects for solid oxide fuel cells. Despite the thickness unevenness at different regions, dense metallic coatings were successfully applied onto all necessary surfaces of the channelled interconnect substrates. Upon oxidation, spinel oxide coatings with very low Cr content were formed, reducing effectively the Cr release. Among the three protective coatings, Co–Cu coating showed the lowest area specific resistance (<15 mΩ cm2 at 800 °C). 相似文献
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Wolfgang Schafbauer Norbert H. Menzler Hans P. Buchkremer 《International Journal of Applied Ceramic Technology》2014,11(1):125-135
This contribution describes the development of tape casting for solid oxide fuel cells (SOFCs) anode supports starting with the characterization of the powders and ending with manufacturing of cells for stack testing. After casting the support, full cells were prepared by screen printing and sintering of the functional layers. The results of single‐cell and stack tests of the novel SOFC will be discussed. The new cell showed excellent electrochemical performance in single‐cell tests with more than 1.5 A/cm2 (800°C, 0.7 V). Furthermore, stack tests showed no significant difference from earlier standard cells when operated at 800°C with a current density of 0.5 A/cm2. 相似文献
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Robert Mücke Norbert H. Menzler Hans Peter Buchkremer Detlev Stöver 《Journal of the American Ceramic Society》2009,92(S1):S95-S102
High-performance solid oxide fuel cells require a thin and gas-tight electrolyte membrane that must be coated on a porous and relatively rough support. A pretreatment of the delivered submicronmeter electrolyte powder of 8 mol%-yttria-stabilized zirconia (8YSZ) yielded a reduced sintering mismatch between the anode substrate made from NiO/8YSZ and the electrolyte coating. Furthermore, it also enhanced the powder packing inside the green film. Constrained sintering usually leads to inadequate film density and an unfavorable pore deformation and orientation. It was demonstrated that these limitations can be resolved by using a coshrinking substrate in a planar cell design. Relative densities of >97% were achieved, which are higher than those for free-standing layers. Additionally, the camber behavior was investigated in dependence of the temperature program with and without gravity effects, giving an overall suggestion for the cofiring parameters of the electrolyte. 相似文献
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R. Wilkenhoener H. P. Buchkremer D. Stoever D. Stolten A. Koch 《Journal of Materials Science》2001,36(7):1775-1782
Furnace brazing to attach metallic plates to LaCrO3 end plates in solid oxide fuel cell (SOFC) was investigated. The metallic plates act as a current collector to which a few conducting wires made of conventional heat-resisting alloys can be attached. The alloy CrFe5Y2O31 was found to be a suitable material for the current collector because its thermal expansion coefficient matches that of LaCrO3 better than heat-resisting nickel- or iron-based alloys. Among various filler alloys tested, SCP6 (Cu with 18 wt% Pd) enables the best wetting of LaCrO3 and CrFe5Y2O31 plates, leading to good adhesion between them. Several approaches were successfully pursued to reduce the bending of brazed LaCrO3/SCP6/CrFe5Y2O31 joints. The area specific resistance of some LaCrO3/SCP6/CrFe5Y2O31 joints increased slightly during annealing (1000°C in air for 2400 h) due to oxidation in the filler alloy. Nevertheless, it remained below the target limit of 0.2 · cm2. 相似文献
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E. Sominski A. Gedanken N. Perkas H. P. Buchkremer N. H. Menzler L. Z. Zhang J. C. Yu 《Microporous and mesoporous materials》2003,60(1-3):91-97
A sonochemical process for the fabrication of the mesoporous composite NiO/yttria stabilized zirconia (YSZ) is described. Its surface area after the extraction of the surfactant is 193 m2/g for a sample containing 40 atom-% Ni. The main advantages of the sonochemical method, as compared with previous works, are the short reaction time (6 h) and that there is no requirement for the glycolation of the nickel, yttrium, and zirconium ions. The reduction of NiO/YSZ to the corresponding Ni/YSZ is also reported. 相似文献
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M. Bram C. Stiller H. P. Buchkremer D. Stver H. Baur 《Advanced Engineering Materials》2000,2(4):196-199
The production of highly porous parts from titanium, stainless steel, and nickel‐based superalloys is of increasing interest in lightweight constructions. A new space‐holder method uses carbamide (urea) and ammonium hydrogen carbonate to produce samples with porosities between 60 and 80 %. Depending on the shape and size distribution of the space holder, spherical and angular pores in the range of 0.1–2.5 mm were obtained. 相似文献
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Gutrath BS Beckmann MF Buchkremer A Eckert T Timper J Leifert A Richtering W Schmitz G Simon U 《Nanotechnology》2012,23(22):225707
Photoacoustic (PA) imaging attracts a great deal of attention as an innovative modality for longitudinal, non-invasive, functional and molecular imaging in oncology. Gold nanoparticles (AuNPs) are identified as superior, NIR-absorbing PA contrast agents for biomedical applications. Until now, no systematic comparison of the optical extinction and PA efficiency of water-soluble AuNPs of various geometries and small sizes has been performed.Here spherical AuNPs with core diameters of 1.0, 1.4 and 11.2?nm, nanorods with longitudinal/transversal elongation of 38/9 and 44/12?nm and hollow nanospheres with outer/inner diameters of 33/19, 57/30, 68/45 and 85/56?nm were synthesized. The diode laser set-up with excitations at 650, 808, 850 and 905?nm allowed us to correlate the molar PA signal intensity with the molar extinction of the respective AuNPs. Deviations were explained by differences in heat transfer from the particle to the medium and, for larger particles, by the scattering of light. The molar PA intensity of 1.0?nm AuNPs was comparable to the commonly used organic dye methylene blue, and rapidly increased with the lateral size of AuNPs. 相似文献