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1.
Thesolidelectrolyteisakeycomponentofsolidoxidefuelcell (SOFC) .Dopedceriaisoneofpromis inghigh conductingsolidelectrolyteinSOFC[1,2 ] .Butitiswell knownthatitisdifficulttosinterdopedceriabysolidstatereactioninair .TheCe0 .9RE0 .1O2 -δelectrolytematerialswerepreparedbythesol gelmethod .Thesinteringtemperatureofthesamplescandecreasetoabout 4 0 0K .Theionicconductivityandlinearthermalexpansionpropertiesofsol gelpreparedCe0 .9RE0 .1O2 -δinawidetemperaturerangewerein vestigated .Thepowder…  相似文献   

2.
In order to lower the raw materials cost and develop a novel cathode materials for intermediate temperature solid oxide fuel cell(ITSOFC), using mixed rare earth replacing the expensive pure La2O3 as the raw materials, the powders of Ln0.7Sr0.3-xCaxCo0.9Fe0.1O3-δ (Ln=the mixed rare earth, x=0.05, 0.10, 0.15) for the applications as the cathode materials were prepared by microwave sintering process. The crystal structure and the particles morphology of the obtained powders were characterized by XRD and SEM, the electrical conductivity of all samples sintered at 1200 ℃ for 3 h was also measured as the function of the temperature from 100 to 800 ℃ by DC four-probe method in air. The experimental results show that due to the influence of mixed rare earth the powders of Ln0.7Sr0.3-xCaxCo0.9Fe0.1O3-δ synthesized at 1200 ℃ for 0.5 h with the mean particle size of 1~20 μm was of perovskite and cubic fluorite phase as well a little SrO phase, the electrical conductivity of the samples decreases with the adding Ca2+ content, and are all higher than 100 S·cm-1 from 500 to 700 ℃ when x≤0.10. Ln0.7Sr0.3-xCaxCo0.9Fe0.1O3-δ. Can meet the demand of the electrical properties for the cathode materials in ITSOFC.  相似文献   

3.
Synthesis and Electrical Conductivities of Sm2O3-CeO2 Systems   总被引:1,自引:0,他引:1  
Solidoxidefuelcell(SOFC)hasattracteda greatattentionasapromisingtechniqueforelectrical powergeneration[1].Thecurrentstate of the art SOFCsusesyttriastabilizedzirconia(YSZ)electro lyte,operatesat800~1000℃duetothelowoxy genionicconductivityoftheYSZelect…  相似文献   

4.
采用液-液掺杂工艺制得稀土掺杂钼粉及钼(合金)坯,通过调整掺杂稀土的种类及含量考察了其对钼粉及钼(合金)坯组织及性能的影响,结果表明,掺杂稀土的种类和掺杂含量的变化对Mo - La -Y复合粉体的形貌及尺寸的影响不明显;钼(合金)坯基体颗粒总体上随掺杂含量的增加而变细,而在相同掺杂含量下,双元掺杂比单元掺杂的细化作用更...  相似文献   

5.
Mn0.1Ce0.9Ox and Mn0.1Ce0.6Zr0.30x samples synthesized by sol-gel method were tested for redox properties through the dynamic oxygen storage measurement and characterized using X-ray diffraction, BET, electron paramagnetic resonance, and X-ray photoelectron spectroscopy. The results showed that redox performances of ceria-based materials could be enhanced by synergetic effects between Mn-O and Ce-O. Fresh and aged samples were characterized with the fluorite-type cubic structure similar to CeO2, and furthermore, the thermal stability of Mn0.1Ce0.9Ox materials was improved by the introduction of some Zr atoms. From XPS, it could be concluded that Mn^2+/Mn^3+ redox couples existed on the surface of Mn0.1Ce0.9Ox and Mn0.1Ce0.6Zr0.3Ox samples. Electron paramagnetic resonance researches revealed that there were three types of Mn^2+ species: isolated Mn^2+ substituting for Ce^4+ ions in the lattice with a cubic symmetry, ones in defect with a noncubic symmetry, and at the surface of samples.  相似文献   

6.
稀土氧化物LnO1.5掺杂CeO2-δ固体电解质的缺陷与电导率   总被引:1,自引:1,他引:0  
利用缺陷化学的知识,对定量求解稀土氧化物LnO1.5掺杂CeO2-δ固体电解质中氧离子空位的浓度进行了初步探讨.在此基础上,推导出了该固体电解质的离子电导率和电子电导率的表达式.并且得出了计算CeO2基固体电解质临界氧分压P*O2的公式,利用该公式对两个问题进行了简单分析.  相似文献   

7.
利用中止还原的方法,研究了稀土元素对掺杂钨粉还原过程及其性能的影响。结果表明,在同样的还原工艺条件下,稀土元素能使掺杂钨粉的还原速率减小,分裂时间更晚,但最终的钨粉粒度更细小,可获得几百纳米的超细钨粉。还原后,粉末的形貌由准球形转变为规则的立方体形。稀土元素还促进钨粉中钾含量的提高。  相似文献   

8.
利用低温燃烧合成法制备了Al2O3掺杂浓度为0.5%~10%(摩尔分数,以下同)的Al2O3/Ce0.8Y0.2O1.9固体电解质复合材料。研究了Al2O3掺杂浓度对Ce0.8Y0.2O1.9固体电解质烧结及电性能的影响。试验结果表明,添加少量的Al2O3可以改善Ce0.8Y0.2O1.9固体电解质的烧结性能,当Al2O3的添加量为0.5%时,电解质粉体具有最佳的烧结性能,1350℃时的相对密度达到99%以上。当Al2O3的掺杂浓度超过其在Ce0.8Y0.2O1.9中的溶解极限时,随Al2O3掺杂量的继续增加,烧结体的相对密度开始下降。阻抗谱结果表明,在溶解极限范围内,Al2O3使Ce0.8Y0.2O1.9的电导率减小,电导活化能增加。Al2O3的掺杂浓度超过溶解极限时,Ce0.8Y0.2O1.9的晶粒电阻不变,由于Al2O3对晶界的"清洁"作用,晶界电阻减小;当Al2O3的掺杂浓度超过5%时,由于Al2O3颗粒对晶界的"阻塞"作用,晶界电阻增加。  相似文献   

9.
Animportantgoalinthedevelopmentofsolidox idefuelcells (SOFCs)istoreducetheoperatingtem peratureofthefuelcellstackfrom 10 0 0℃tobelow85 0℃soastogetanoptimumtrade offbetweenper formanceandlifetimeofthestackandtoreducetheoverallsystemcost[1] .Toachievethisdestinat…  相似文献   

10.
稀土元素的特殊性质及其应用   总被引:5,自引:0,他引:5  
本文从稀土元素微观结构角度,揭示了稀土元素的某些特殊性质,并指出这种特性与应用机理有必然的联系。从而启迪稀土使用者,掌握和了解稀土的基本特性,才能自由地驾驭稀土的应用。  相似文献   

11.
The highly phase-pure electrolyte materials with compositionLa1.9Ba0.1MO1.9Mn0.1O9(LBMMO) was prepared by the sol-gel auto-combustion method for intermediate-temperature solid oxide fuel cells (IT-SOFCs). The details ofgel's auto-combustion, phase evolution, sintering, thermal expansion and electrochemical performance of LBMMO were investigated by means of thermo-gravimetry (TG), X-ray diffxaction (XRD), scanning electron microscopy (SEM), transmission electron spectroscopy (TEM), thermal expansion curve (TEC) and complex impedance spectra. The results showed that the highly phase-pure electrolyte LBMMO could be obtained after calcining at 600 ℃. The sample sintered at 900 ℃ for 4 h in air exhibited a better sinterability, and the relative density of LBMMO was higher than 96%. The electrical conductivities of the sample were 6.7x 10-3 and 25.9× 10-3 S/cm at 700 and 800 ℃ in air, respectively. Results also showed that LBMMO had moderate thermal expansion (a=16.3×10-6 K-l, between room temperature and 800 ℃) and an electrical activation energy equal to 1.32 eV).  相似文献   

12.
The effect of rare earth element Ce on microstructure, electrical conductivity and mechanical properties was studied.Using optical microscope, scanning electron microscope, transmission electron microscope and X-ray diffractometer, the microstructure and phase composition of aluminum rod for electrical purpose were measured and analyzed.The results indicate that rare earth element Ce can considerably refine grain size of aluminum rod for electrical purpose,improve the regular distribution pattern of the impurity, such as silicon and iron which present in the aluminum matrix,form stable metal compound with pernicious impurity.This metal compound precipitates on the crystal boundary.As a result, the solid solubility of impurity in aluminum reduce, and the electrical conductivity of aluminum rod for electrical purpose is improved.It is found that the mechanical properties of aluminum rod for electrical purpose are improved by rare earth element in certain range of RE addition.  相似文献   

13.
掺杂复合稀土氧化物的钼的组织与性能   总被引:5,自引:0,他引:5  
对掺杂一种(以下简称:单元)或一种以上(以下简称:复合)稀土氧化物的钼粉、坯条及不同温度退火丝材的性能及组织结构进行了系统研究。结果表明:复合稀土同单元稀土一样,都能提高钼丝的再结晶温度,复合稀土钼丝表现出优异的高温退火强度,并具有比同含量的单元稀土钼丝更高的延伸率,具有更好的成型性和加工性。  相似文献   

14.
复合稀土钨电极研究   总被引:3,自引:1,他引:3  
测试了几种稀土钨电极的焊接性能,并对其组织结构进行了分析,深入探讨了稀土在不同电极中的作用机理。发现高温下稀土相形状将发生改变,毛细管现象只在电极开始工作时存在。由于传输速率和蒸发速率不同,铈钨电极头部出现贫稀土,侧面形成环状富集;1:2:1镧铈钇电极侧表面富稀土;1:1:3镧铈钇电极表面出现融熔;稀土通过融熔的钨传输到表面;从而保持电极的形状不变和电弧的稳定。  相似文献   

15.
Solidoxidefuelcells (SOFCs)haveseveraldis tinctadvantages ,e .g .,highenergyconversioneffi ciency ,wideadaptabilitytofuels ,theusageofnon preciousmaterials ,noliquids ,nocorrosions ,modularconstructionandmuchlowerproductionofNOx,SOxandnoise .Therefore ,theyreceiveincreasingatten tion[1,2 ] .AtypicalSOFCwhichutilizesyttria stabi lizedzirconia (YSZ)astheelectrolyterequireshighoperationtemperaturesuchas 10 0 0℃togainhighe noughionicconductivity .Loweringtheoperationtem peratureto 80 0℃wou…  相似文献   

16.
张天林 《山西冶金》2013,36(2):55-57
从理论和实际应用两个方面具体阐述了钙-钙双碱法的应用及取得的效果。详细论述了XP型脱硫除尘塔板的运行工艺。以大量的数据显示了钙-钙双碱法的实际应用情况,在同样条件下将XP型塔板与旋流塔板从脱硫效率和除尘效率两方面分别进行了比较。  相似文献   

17.
A novel catalytic material Lao.9Sr0.1MnO3 and tourmaline compound catalytic material was synthesized in the base of traditional catalytic material La0.9Sr0.1MnO3 which exhibited excellent catalytic activity for methane combustion. Different contents of toumaaline were added to give a series ofLa0.9Sr0.1MnO3 and tourmaline catalytic material through a sol-gel method. Samples above were characterized and analyzed by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller method (BET), temperaalre programmed reduction (TPR), catalytic activity test and contact angle test. The as-prepared sample with 2% (m/m) tourmaline showed good homogeneity surface morphology and displayed the optimal catalytic activity. The light-off temperature reduced by 10 ℃ and the T90 decreased by 15 ℃. In addition, the mechanism of the reinforcement of catalytic activity was explored.  相似文献   

18.
采用溶胶.凝胶法制备了一系列的BaTiO3:xTb4O7,BaTi0.09Zr0.1O3;:xTb4O7粉体。测试表明所获得陶瓷在室温具有高介电常数。通过XRD衍射和SEM扫描电镜分别对粉体的结构和陶瓷的形貌进行了表征。此外,采用溶胶.凝胶法合成BaTi0.09Zr0.1O3后,再用固相法掺杂了Tb4O7介-温测试表明固相掺杂Tb4O7使陶瓷的居里温度向低温方向移动,陶瓷的室温介电常数显著提高。  相似文献   

19.
The forming-regions and properties were studied on phosphate system glasses Sm2O3 doped by two step melting method. It shows that with the increasing of rare earth content, the forming-regions would shrink and the content of Sm2O3 should be controlled in 15 mol %. The structure and absorption spectrum were tested by infra-red spectrum and spectrophotometer. The experimental results provide that with the. increasing of Sm2O3 content, the characteristic absorption peak of 1280 cm- 1 would move to the low wave numbers and vibration weakening, in the absorption spectrum,the intensity of characteristic absorption peak was enhanced and broadened at 1075 nm, and the transmittance of 1060 nm is lessthan 1% .  相似文献   

20.
Amonglanthanideions ,Eu3 + ionposs esesgoodluminescentcharacteristics ,highcolorpurityandhighquantumefficiency .Eu3 + isoneofthecentralionsfirstselectedforthepreparationofrareearthionsdopedlumi nescentmaterials .Dafinovaetal .[1] producedEu3 + andSO2 -4 dopedtungsta…  相似文献   

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