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11.
Nickel oxide and chromium-doped nickel oxide (Ni0.95Cr0.03O1−δ
) were prepared by thermal decomposition of nitrates. The obtained NiO and Ni0.95Cr0.03O1−δ
samples were utilized as sensing electrodes (SEs) in yttria-stabilized zirconia (YSZ)-based sensors for detection of NO2 at 800 °C under wet condition (5 vol.% H2O). While the mixed-potential-type planar sensor attached with NiO-SE gave rather large NO2 sensitivity, the sensor attached with Ni0.95Cr0.03O1−δ
-SE exhibited fast recovery rate with an acceptable sensitivity. The Δemf (electromotive force) of the sensors varied linearly
with NO2 concentration in the examined range of 50–400 ppm on a logarithmic scale. Based on the results of measurements for polarization,
complex impedance and gas phase catalysis, the fast recovery was attributable to the high rate for the anodic reaction of
O2 at the Ni0.95Cr0.03O1−δ
/YSZ interface, and the lower NO2 sensitivity was caused by both the high rate for the anodic reaction of O2 and the high degree for the gas phase conversion of NO2 to NO. 相似文献
12.
为改善 8YSZ 材料的力学性能,利用呈板片状结构的 LaMgAl11O19 来强韧化 8YSZ 陶瓷,在 1600 ℃下保温 3 h制备了LaMgAl11O19 -8YSZ 复相陶瓷,研究了 LaMgAl11O19 的添加量对 8YSZ 基复相陶瓷的致密度、显微形貌和力学性能的影响.结果表明,添加板片状 LaMgAl11O19可较明显地改善8YSZ陶瓷的力学性能.当 LaMgAl11O19 的添加量为 20 wt;时,8YSZ基复相陶瓷的抗弯强度和断裂韧性分别为297.4 MPa和4.0 MPa·m1/2. 相似文献
13.
YSZ中温燃料电池的稳态模拟 总被引:1,自引:0,他引:1
依据同时考虑电化学及热平衡耦合的二维模拟软件 ,计算了薄膜钇稳氧化锆 (YSZ)中温燃料电池在不同工作条件下的稳态特性 .通过电流~电压关系参数进行自拟合实验 ,格点选取由平衡收敛性和计算效率而得 ,研究了不同连接体、气流流向设计等工作条件下的温度场 ,给出了不同工作温度下输出功率及电池效率与工作电压的关系 .对温度场的分析表明 :电池板内最高温度及最大温差以并流为最小 ,交叉流为最大 ,并流是最好的气流流向设计 .与以陶瓷材料作连接体相比 ,使用金属连接体能显著减小热应力和电池板内最高温度 ,受益最大的是交叉流 ,其最高温度及最大温差均小于陶瓷连接体的并流设计 .不同的气流流向对于输出功率及电池效率影响很小 ,对并流和金属连接体组合 ,给出了工程设计的燃料分布、电流密度、Nernst势及温度梯度在典型工作条件下的情形 相似文献
14.
真空注浆法制备YSZ电解质膜管及其在固体氧化物燃料电池中的应用 总被引:7,自引:0,他引:7
以吡啶为分散剂,采用真空注浆法制备出膜厚为0.2mm、长度为140mm的致密YSZ电解质膜管。研究了烧结温度对样品致密度和离子导电率的影响.用1650℃烧结2h制备的致密YSZ电解质膜管组装成固体氧化物燃料电池,以氢气和煤气为燃料,研究了电池在500~900℃的电化学性能.实验结果表明,用真空注浆法可制备出高质量和高密度的YSZ电解质膜管,在1600℃烧结后,其相对密度已达到理论密度的98.1%,接近理论密度.单电池的开路电压最大值为1.213V,最大输出功率为0.48W.以氢气为燃料的燃料电池性能明显高于以煤气为燃料的电池性能. 相似文献
15.
Jung-Hyun Kim Rak-Hyun Song Jong-Hee Kim Tak-Hyoung Lim Yang-Kook Sun Dong-Ryul Shin 《Journal of Solid State Electrochemistry》2007,11(10):1385-1390
Nano-sized LSM–YSZ composite was co-synthesized by a glycine–nitrate process (GNP). Transmission electron microscopy revealed
that the as-prepared LSM–YSZ particles consist of nano-sized powders with a dominant YSZ phase. Backscatter electron image
shows that LSM and YSZ phases were regularly dispersed within the composite. Alternating current impedance measurement revealed
that the co-synthesized LSM–YSZ electrode shows lower polarization resistance and activation energy than the physically mixed
LSM–YSZ electrode. This electrochemical improvement would be attributed to the increase in three-phase boundary and good dispersion
of LSM and YSZ phases within the composite.
This paper is dedicated to Professor Su-Il Pyun on the occasion of his 65th birthday. 相似文献
16.
采用脉冲激光沉积技术(PLD), 在MgO单晶基底上, 依次沉积氧化钐掺杂的氧化铈(Ce0.8Sm0.2O2-δ, SDC)和钇稳定氧化锆(8 mol%Y2O3:ZrO2, YSZ)制备了五种(SDC/YSZ)N (N=3, 5, 10, 20, 30) 超晶格电解质薄膜. 利用X射线衍射(XRD)、高分辨透射电子显微镜(HR-TEM)和交流阻抗对其形貌、相结构和电学性能进行了表征. 结果显示, (SDC/YSZ)N超晶格电解质薄膜之间形成了明显的界面和较好的超晶格结构; 薄膜表面颗粒生长均匀、致密、平滑, 在薄膜的界面处没有元素相互扩散也未出现裂纹, 外延生长良好; 电导率随着(SDC/YSZ)N超晶格电解质界面数的增加而增加, 而活化能则随之减少, 是较为理想的低温固体氧化物燃料电池电解质. 相似文献
17.
Xiong Yin Catherine Choong Liang Hong Zhaolin Liu 《Journal of Solid State Electrochemistry》2006,10(8):643-650
This work reports a new design of asymmetric tubular oxygen-permeable ceramic membrane (OPCM) consisting of a porous Y2O3 stabilized ZrO2 (YSZ) tube (with ∼1 μm of pore diameters and 31% porosity) as the support and a gas-tight mixed conductive membrane. The
membrane has an interlocking structure composed of a host matrix, Ag(Pd) alloy (9:1 by wt) doped perovskite-type (LSM80, 90wt%), and the embedded constituent, pristine LSM80. The Ag(Pd) alloy component promotes not only electronic conductivity
and mechanical strength but also reduction of both porosity and pore sizes in the layer (∼10-μm-thick) where it dopes. The
porous structure in this layer could then be closed through a solution coating procedure by which ingress of an aqueous solution
containing stoichiometric nitrate salts of La3+, Mn3+, and Sr2+ to the pore channels takes place first and the mixture of nitrate salts left after drying is subjected to pyrolysis to generate
tri-metal oxides in situ. This is followed by calcinations at l,300 °C to consolidate the embedded trioxide and to cohere
them with the Ag(Pd)-LSM80 host matrix. The structure formed is dubbed LSM80(S)-Ag(Pd)-LSM80, which was confirmed gas-tight
by electron micrograph and N2 permeation test. Finally, we assess the chemical compatibility between LSM80 and YSZ at the sintering temperature by X-ray
diffraction and electrochemical impedance analysis. The oxygen permeation of the fabricated LSM80(S)-Ag(Pd)-LSM80-YSZ membrane
is within the temperature range of 600 to 900 °C. The tests reveal good compatibility between the LSM80 and YSZ and a reasonably
high oxygen permeation flux in association with this OPCM assembly. 相似文献
18.
研究了Y2O3稳定的ZrO2(YSZ)氧离子传导膜H2S固体氧化物燃料电池性能。掺杂NiS、电解质、Ag粉和淀粉制备了双金属复合MoS2阳极催化剂,掺杂电解质、Ag粉和淀粉制备了复合NiO阴极催化剂,用扫描电镜对YSZ和膜电极组装(MEA)进行了表征,比较了不同电极催化剂的性能和极化过程,考察了不同温度对电池性能的影响。结果表明,双金属复合MoS2/NiS阳极催化剂在H2S环境下比Pt和单金属MoS2催化剂稳定,复合NiO阴极催化剂比Pt性能好,在电极催化剂中加入Ag可显著提高电极的导电性;与Pt电极相比,复合MoS2阳极和复合NiO阴极催化剂的过电位较小,阳极的极化比阴极侧小;温度升高,电池的电流密度与功率密度增加,电化学性能变好。在750℃、800℃、850℃和900℃及101.13 kPa时,结构为H2S、(复合MoS2阳极催化剂)/YSZ氧离子传导膜/(复合NiO阴极催化剂)、空气的燃料电池最大功率密度分别为30 mW/cm2、70 mW/cm2、155 mW/cm2及295 mW/cm2、最大电流密度分别为120 mA/cm2、240 mA/cm2、560 mA/cm2和890 mA/cm2。 相似文献
19.
Pt/YSZ固体电解质界面氧的电荷传递过程研究 总被引:7,自引:0,他引:7
用极化法研究了不同温度和氧分压下Pt/YSZ界面氧的电荷传递过程.研究发现氧电荷传递过程的阴、阳极电荷传递系数为1,不随温度和氧分压而变.从实验和反应机理推导得到,Pt/YSZ界面的交换电流密度和氧分压之间存在,i0=2FKr(KO2PO2)1/4(1+KO2PO2)1/2的关系.通过数学分析还获电化学反应速度常数,氧在Pt表面上吸附平衡常数等重要参数 相似文献
20.
200keV Xe+离子辐照使单晶YSZ由无色透明变成紫色透明,结果表明,能量为200keV,注量为1×1017cm-22的Xe+离子辐照YSZ单晶产生的损伤高达350dpa,在损伤区产生高密度的缺陷,但仍然没有发生非晶化转变。吸收光谱测试结果表明,产生吸收带的注量阈值大约为1016cm-2。注量为1×1016cm-2和1×1017cm-2的样品,吸收带峰值分别位于522nm和497nm。光吸收带可能与Zr阳离子最近邻的氧空位捕获电子形成的F型色心和Y阳离子近邻的氧离子捕获空穴形成的V型色心有关。 相似文献