The Experts below are selected from a list of 1578 Experts worldwide ranked by ideXlab platform
Lorenz Singheiser - One of the best experts on this subject based on the ideXlab platform.
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investigation of chromium vaporization from interconnector steels with spinel coatings
Journal of The Electrochemical Society, 2010Co-Authors: R Trebbels, Torsten Markus, Lorenz SingheiserAbstract:The vaporization of Cr-rich volatile species from interconnector materials for high temperature solid oxide fuel cells (SOFCs) is considered to be a major source of degradation that limits the lifetime of planar SOFC systems [Fujita, J. Power Sources, 131, 262 (2004); 160, 1104 (2006); Hilpert, J. Electrochem. Soc., 143, 3642 (1996); Kurukowa, Solid State Ionics, 178, 287 (2007); Quadakkers, SOFC Forum, p. 323 (1994); Quadakkers, European Oxide Fuel Cell Forum, p. 297 (1996)]. For a longer lifetime of these systems, the Cr vaporization of interconnector material is reduced [Collins, Surf. Coat. Technol., 201, 4467 (2006)]. The potential of reduction of Cr vaporization using coatings with spinel layers is the subject of the present work. In this study, the influence of processing parameters for Crofer22APU coated with a spinel based on (Mn,Co,Fe) 3 O 4 on the Cr vaporization rates was studied at 800°C in air using the transpiration method. The measured Cr release of the coated samples was compared to an uncoated Crofer22APU. The aim of this work was to find the optimum conditions to prepare the spinel coating with regard to Cr vaporization.
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chromium vaporization from high temperature alloys i chromia forming steels and the influence of outer oxide layers
Journal of The Electrochemical Society, 2007Co-Authors: Michael Stanislowski, Klaus Hilpert, Torsten Markus, E Wessel, Lorenz SingheiserAbstract:The vaporization of chromium species from chromia scales limits the applicability of chromia-forming steels at high temperatures and is one of the major reasons for degradation in the development of planar solid oxide fuel cells (SOFCs). Cr(VI) vaporized from the interconnector is reduced at the cathode and deposits in the form of solid Cr(III)-oxide, thereby inhibiting the electrochemical processes. This work presents the first systematic study on the Cr vaporization of Cr-, Fe-, Ni-, and Co-based alloys in air and in H 2 atmospheres at high temperatures. The influence of outer oxide layers of (Cr,Mn) 3 O 4 , (Fe, Cr) 3 O 4 , Co 3 O 4 , TiO 2 , and Al 2 O 3 on the Cr vaporization is investigated. It is shown that the Cr vaporization of chromia-forming steels can be reduced by more than 90% by alloying. An estimate of the expected degradation effects on planar SOFC designs for the use of uncoated interconnector materials is used to show that in order to achieve the desired lifetimes for SOFC systems, additional Cr-retention coatings are necessary. Additionally, equilibrium vaporization measurements are carried out for pure Cr 2 O 3 (s) in humid air in order to elucidate controversies in the literature concerning the thermodynamic data of CrO 2 (OH) 2 (g).
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Reduction of chromium vaporization from SOFC Interconnectors by highly effective coatings
Journal of Power Sources, 2007Co-Authors: Michael Stanislowski, Jan Froitzheim, Leszek Niewolak, Klaus Hilpert, Thorsten Markus, Willem J. Quadakkers, Lorenz SingheiserAbstract:The vaporization of Cr-rich volatile species from interconnector materials is a major source of degradation that limits the lifetime of planar SOFC systems with metallic interconnects. In this study, the vaporization of Cr species of a variety high chromium alloys was studied at 800 °C in air using the transpiration method. The measured release of Cr species of the different alloys was correlated with the formed outer oxide scales. A quantitative estimation showed that all the investigated alloys failed to meet the requirements concerning the Cr release from interconnector materials for SOFCs or formed oxide scales which possessed too high electrical resistances. Sputtered ceramic coatings of LSM and LSC and metallic coatings of Co, Ni and Cu were tested with regard to their suitability for Cr retention. The sputtered perovskite coatings turned out to be ineffective in reducing the Cr release to the desired levels. With metallic coatings of Co, Ni or Cu the Cr release could be reduced by more than 99%. The metallic coatings and their oxides effectively reduced the growth of the oxide scale on the steel substrate and showed negligible vaporization rates for Co, Cu and Ni, respectively. Therefore, Co, Ni or Cu were identified as promising and cheap coating materials for metallic Interconnectors.
Jiangsha Che - One of the best experts on this subject based on the ideXlab platform.
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Interconnectors in tandem organic light emitting diodes and their influence on device performance
IEEE Journal of Selected Topics in Quantum Electronics, 2016Co-Authors: Yonghua Che, Jiangsha CheAbstract:In this paper, we present a comprehensive review on recent progress of Interconnectors in tandem organic light emitting diodes, from structure design to performance and their working principles. We will introduce the most commonly used Interconnectors, discuss in detail the main features of them, as well as the advantages and disadvantages of each type. Especially, organic heterojunction type Interconnectors are highlighted.
Shaorong Wang - One of the best experts on this subject based on the ideXlab platform.
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performance of an anode supported tubular solid oxide fuel cells stack with two single cells connected by a co sintered ceramic interconnector
International Journal of Hydrogen Energy, 2011Co-Authors: Yanjie Xu, Shaorong Wang, Le ShaoAbstract:Abstract Two anode-supported tubular solid oxide fuel cells (SOFCs) have been connected by a co-sintered ceramic interconnector to form a stack. This novel bilayered ceramic interconnector consists of La-doped SrTiO 3 (La 0.4 Sr 0.6 TiO 3 ) and Sr-doped lanthanum manganite (La 0.8 Sr 0.2 MnO 3 ), which is fabricated by co-sintering with green anode at 1380 °C for 3 h. La 0.4 Sr 0.6 TiO 3 (LST) acts as a barrier avoiding the outward diffusion of H 2 to the cathode; while La 0.8 Sr 0.2 MnO 3 (LSM) prevents O 2 from diffusing inward to the anode. The compatibility of LST and LSM, as well as their microstructure which co-sintered with anode are both studied. The resistances between anode and LST/LSM interconnector at different temperatures are determined by AC impedance spectra. The results have showed that the bilayered LST/LSM is adequate for SOFC interconnector application. The active area is 2 cm 2 for interconnector and 16 cm 2 for the total cathode of the stack. When operating at 900 °C, 850 °C, 800 °C with H 2 as fuel and O 2 as oxidant, the maximum power density of the stack are 353 mW cm −2 , 285 mW cm −2 and 237.5 mW cm −2 , respectively, i.e., approximately 80% power output efficiency can be achieved compared with the total of the two single cells.
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a novel bilayered sr0 6la0 4tio3 la0 8sr0 2mno3 interconnector for anode supported tubular solid oxide fuel cell via slurry brushing and co sintering process
Journal of Power Sources, 2011Co-Authors: Yanjie Xu, Shaorong WangAbstract:Abstract Considering that conventional lanthanum chromate (LaCrO 3 ) interconnector is hard to be co-sintered with green anode, we have fabricated a novel bilayered interconnector which consists of La-doped SrTiO 3 (Sr 0.6 La 0.4 TiO 3 ) and Sr-doped lanthanum manganite (La 0.8 Sr 0.2 MnO 3 ). Sr 0.6 La 0.4 TiO 3 is conductive and stable in reducing atmosphere, locating on the anode side; while La 0.8 Sr 0.2 MnO 3 is on the cathode side. A slurry-brushing and co-sintering method is applied: the Sr 0.6 La 0.4 TiO 3 and La 0.8 Sr 0.2 MnO 3 slurries are successively brushed onto green anode specimen, followed by co-firing course to form a dense bilayered Sr 0.6 La 0.4 TiO 3 /La 0.8 Sr 0.2 MnO 3 interconnector. For operating with humidified hydrogen and oxygen at 900 °C, the ohmic resistances between anode and cathode/interconnector are 0.33 Ω cm 2 and 0.186 Ω cm 2 , respectively. The maximum power density is 290 mW cm −2 for a cell with interconnector, and 420 mW cm −2 for a cell without it, which demonstrates that nearly 70% of the power output can be achieved using this bilayered Sr 0.6 La 0.4 TiO 3 /La 0.8 Sr 0.2 MnO 3 interconnector.
Yanjie Xu - One of the best experts on this subject based on the ideXlab platform.
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performance of an anode supported tubular solid oxide fuel cells stack with two single cells connected by a co sintered ceramic interconnector
International Journal of Hydrogen Energy, 2011Co-Authors: Yanjie Xu, Shaorong Wang, Le ShaoAbstract:Abstract Two anode-supported tubular solid oxide fuel cells (SOFCs) have been connected by a co-sintered ceramic interconnector to form a stack. This novel bilayered ceramic interconnector consists of La-doped SrTiO 3 (La 0.4 Sr 0.6 TiO 3 ) and Sr-doped lanthanum manganite (La 0.8 Sr 0.2 MnO 3 ), which is fabricated by co-sintering with green anode at 1380 °C for 3 h. La 0.4 Sr 0.6 TiO 3 (LST) acts as a barrier avoiding the outward diffusion of H 2 to the cathode; while La 0.8 Sr 0.2 MnO 3 (LSM) prevents O 2 from diffusing inward to the anode. The compatibility of LST and LSM, as well as their microstructure which co-sintered with anode are both studied. The resistances between anode and LST/LSM interconnector at different temperatures are determined by AC impedance spectra. The results have showed that the bilayered LST/LSM is adequate for SOFC interconnector application. The active area is 2 cm 2 for interconnector and 16 cm 2 for the total cathode of the stack. When operating at 900 °C, 850 °C, 800 °C with H 2 as fuel and O 2 as oxidant, the maximum power density of the stack are 353 mW cm −2 , 285 mW cm −2 and 237.5 mW cm −2 , respectively, i.e., approximately 80% power output efficiency can be achieved compared with the total of the two single cells.
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a novel bilayered sr0 6la0 4tio3 la0 8sr0 2mno3 interconnector for anode supported tubular solid oxide fuel cell via slurry brushing and co sintering process
Journal of Power Sources, 2011Co-Authors: Yanjie Xu, Shaorong WangAbstract:Abstract Considering that conventional lanthanum chromate (LaCrO 3 ) interconnector is hard to be co-sintered with green anode, we have fabricated a novel bilayered interconnector which consists of La-doped SrTiO 3 (Sr 0.6 La 0.4 TiO 3 ) and Sr-doped lanthanum manganite (La 0.8 Sr 0.2 MnO 3 ). Sr 0.6 La 0.4 TiO 3 is conductive and stable in reducing atmosphere, locating on the anode side; while La 0.8 Sr 0.2 MnO 3 is on the cathode side. A slurry-brushing and co-sintering method is applied: the Sr 0.6 La 0.4 TiO 3 and La 0.8 Sr 0.2 MnO 3 slurries are successively brushed onto green anode specimen, followed by co-firing course to form a dense bilayered Sr 0.6 La 0.4 TiO 3 /La 0.8 Sr 0.2 MnO 3 interconnector. For operating with humidified hydrogen and oxygen at 900 °C, the ohmic resistances between anode and cathode/interconnector are 0.33 Ω cm 2 and 0.186 Ω cm 2 , respectively. The maximum power density is 290 mW cm −2 for a cell with interconnector, and 420 mW cm −2 for a cell without it, which demonstrates that nearly 70% of the power output can be achieved using this bilayered Sr 0.6 La 0.4 TiO 3 /La 0.8 Sr 0.2 MnO 3 interconnector.
Yonghua Che - One of the best experts on this subject based on the ideXlab platform.
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Interconnectors in tandem organic light emitting diodes and their influence on device performance
IEEE Journal of Selected Topics in Quantum Electronics, 2016Co-Authors: Yonghua Che, Jiangsha CheAbstract:In this paper, we present a comprehensive review on recent progress of Interconnectors in tandem organic light emitting diodes, from structure design to performance and their working principles. We will introduce the most commonly used Interconnectors, discuss in detail the main features of them, as well as the advantages and disadvantages of each type. Especially, organic heterojunction type Interconnectors are highlighted.