固体氧化物燃料电池阳极的制备及表征

本文介绍了固体氧化物燃料电池对阳极材料的基本要求以及各种阳极材料的优缺点及其研究进展(包括金属、金属陶瓷、混合导体氧化物等)。以Co2O3和钐掺杂氧化铈(SDC)为原料,通过粉末冶金工艺制备出用于燃料电池的Co2O3/SDC阳极烧结体和Co/SDC阳极材料,并用X射线衍射仪(XRD)对产物的微观结构进行了表征,证明在不同Co2O3含量的样品中晶体结构非常稳定,烧结后Co3O4均匀的分布在样品内。     

Ba掺杂SrTiO3SOFC阳极材料的制备与电性能分析

采用高温固相法合成BaxSr1-x TiO3-δ(x=1～0.3,摩尔分数)粉体,制备固体氧化物燃料电池(solid oxide fuel cell,SOFC)阳极材料,并对材料进行X射线衍射、扫描电子显微镜分析及相对致密度、高温电导的测量.Ba的掺入增大材料的晶胞参数,但是阻碍材料的致密化,材料的电子电导率和离子电导...     

固体氧化物燃料电池LnBaCo_2O_(5+δ)-La_(10)Si_6O_(27)复合阴极的制备

为探索适于中温条件下使用的固体氧化物燃料电池的阴极材料,利用溶液浸渍法,制备了具有阴极与电解质一体化离子传导路径的LnBaCo2O5+δ-La10Si6O27(Ln=Gd,Sm,Nd)复合阴极。通过X射线衍射仪和扫描电子显微镜研究了阴极相结构、微观形貌。利用交流阻抗谱对电极的性能进行了研究。结果表明,SmBaCo2O5+δ-La10Si6O27复合阴极在空气中的界面极化电阻最小,700℃为0.518Ω.cm2。     

硬币状氧化镍的制备及其电化学性能研究

通过均匀沉淀法,以氨水作为络合剂,制备了β-氢氧化镍,经450℃煅烧处理得到纳米氧化镍,通过充放电测试和循环伏安测试研究了该产物作为锂离子电池负极材料的电化学性能.XRD、IR表明,反应产物为纯相,SEM和TEM表明,产物形貌为硬币状的特殊形貌.在放电电位区间0.01～3.0 V vs Li/Li＋,0.2C倍率下充放电,初始容量1 050 mAh/g,第2次容量损失35.8％,50次循环后,质量比容量为355 mAh/g,硬币状纳米氧化镍其特殊的形貌具有较大的比表面积,增加了电化学活性点,降低了界面反应的极化,从而提高了NiO电极的电化学性能.     

固体氧化物燃料电池CuCoNi/SDC阳极微结构与电性能的研究

本论文采用溶胶-凝胶低温燃烧合成法制作CuxCo0.5-xNi0.5O1.75-0.5x固溶体阳极粉末,并将电解质粉末和阳极合金粉末按1:1的比例制作了CuCoNi/SDC阳极片。采用热重差热仪检测粉末的处理情况,采用x射线衍射仪(XRD)检测了粉末的成相情况。并且采用四端子法检测了不同组成阳极片的电导率值。分析了固体氧化物燃料电池CuCoNi/SDC阳极的显微结构。结果显示,用上述方法合成的粉体成相很好,阳极片的电导率和组成、温度有着极强的联系,氢气还原前后微结构有明显的变化。     

固体氧化物燃料电池LnBaCo2O5 δ-La10Si6O27复合阴极的制备与研究

利用溶液浸渍法,制备了具有阴极与电解质一体化离子传导路径的新型LnBaCo2O5 δ-La10Si6O27 (Ln=Gd, Sm, Nd) 复合阴极,在此基础上,通过X射线衍射仪和扫描电子显微镜研究了阴极相结构、微观形貌等,并利用交流阻抗谱研究其电化学性能。研究表明此复合阴极表现出比较优异的阴极性能,是一类很有应用前景的中低温固体氧化物燃料电池的阴极材料。     

SOFC中低浓度干甲烷在Ni/YSZ阳极上的反应

固体氧化物燃料电池(SOFC)趋向于直接使用甲烷天然气为燃料,确定甲烷在固体氧化物燃料电池阳极发生的化学与电化学反应非常重要.以Ni/YSZ为阳极、YSZ板做电解质、LSM为阴极,用涂浆法制作电解质支撑的电池,研究低浓度干甲烷在固体氧化物燃料电池中的反应.改变甲烷浓度、电池工作温度、电解质厚度,用在线色谱测量不同电流密度下,阳极出口气体产生速率.根据阳极出口气体产生速率变化,分析干甲烷在阳极的反应变化.通过氧消耗计算和转移电子数的分析,说明甲烷在电池阳极发生不同类型的反应.电流密度小时,甲烷发生部分氧化反应.电流密度大时,发生氢氧化和CO氧化,部分甲烷发生总反应为完全氧化的反应.部分甲烷发生完全氧化反应的同时,部分甲烷仍发生部分氧化反应,但其反应速率随电流密度增加逐渐降低.甲烷浓度和试验温度增加,甲烷开始发生完全氧化的电流密度增加.     

直孔阳极支撑体及阳极功能层的制备方法及其单电池性能

采用海藻酸盐离子凝胶法制备直孔Ni–YSZ阳极支撑体,制备了一体化的Ni–YSZ阳极支撑体及阳极功能层(AFL).直孔Ni–YSZ阳极支撑体内分布着大量直通孔道,孔径约为80μm,采用浆料旋涂法在其上制备的Ni–YSZ阳极功能层厚度为130μm.而采用一体化法制备的阳极支撑体,其孔道呈发散状分布,孔径在20～60μm之...     

阳极支撑三层一体化结构电池的制备及性能

采用流延工艺制备了NiO-8％Y2O3/ZrO2(YSZ)阳极支撑三层一体化结构单电池,在此基础上采用浸渍工艺在多孔YSZ基体上低温制备了高活性阴极La0.6Sr0.4Co0.2Fe0.8O3-δ (LSCF).研究发现:降低电极制备温度可以得到微观形貌可控、分布均匀的纳米电极,并且避免了电极与基体间的反应:通过控制浸渍次数,制备了不同LSCF含量的电池;随着浸渍量的增加,电极的极化电阻显著下降;在800℃时,LSCF质量分数为45％的电池的功率密度高达1090 mW/cm2,同时电池稳定运行90h,表现出了很好的稳定性.     

Cu-Ce-Zr-O／YSZ阳极材料以甲烷为燃料时的抗积炭性能

为研究甲烷在固体氧化物燃料电池中操作稳定性,分别采用共沉淀法和柠檬酸溶胶.凝胶法制备了10%CuO-Ce0.15Zr0.85O2催化剂,并以此为阳极催化剂、LSM为阴极制成了YSZ电解质支撑的SOFC单电池.用XRD对材料进行表征;用SEM对阳极,阴极进行表征.以甲烷为燃料对单电池发电性能进行测试,研究了两种不同方法制备的Cu-Ce-Zr-O阳极催化剂的抗积炭性能.相对于共沉淀法,溶胶-凝胶法制备的阳极结构和发电性能都要优于前者.长期稳定性方面,共沉淀法和溶胶.凝胶法制备的Cu-Ce-Zr-O/YSZ阳极都较传统的Ni-YSZ阳极更能够长期稳定运行.     

造孔剂含量对固体氧化物燃料电池阳极的结构与电性能的影响

通过向阳极添加造孔剂（PMMA）改善阳极的微观结构,研究不同含量的造孔剂（PMMA）对阳极的显微结构、电性能的影响。利用SEM、电化学1二作站等测试手段对单电池的结构和电性能进行了表征。研究结果表明,添加7wt．％的PMMA造孔剂制备的单电池,阳极的孔隙率高,阳极中的气孔分布均匀,结构规整,降低了燃料气的传输阻力,提高了三相反应界面,获得了良好的电性能。以H2＋3％H：0为燃料气,在750℃下单电池的开路电压（OCV）为1．08V、最大功率密度为0．82W／cm2、欧姆阻抗为0．20Ω·cm2、两极阻抗为0．53Ω·cm2。     

Synthesis of Highly Porous Yttria-Stabilized Zirconia by Tape-Casting Methods

Porous ceramics of Y₂O₃-stabilized ZrO₂ (YSZ) were prepared by tape-casting methods using both pyrolyzable pore formers and NiO followed by acid leaching. The porosity of YSZ wafers increased in a regular manner with the mass of graphite or polymethyl methacrylate (PMMA) to between 60% and 75% porosity. SEM indicated that the shape of the pores in the final ceramic was related to the shape of the pore formers, so that the pore size and microstructure of YSZ wafers could be controlled by the choice of pore former. Dilatometry measurements showed that measurable shrinkage started at 1300 K, and a total shrinkage of 26% was observed, independent of the amount or type of pore former used. Temperature-programmed oxidation (TPO) measurements on the green tapes demonstrated that the binders and dispersants were combusted between 550 and 750 K, that PMMA decomposed to methyl methacrylate between 500 and 700 K, and that graphite combusted above 900 K. The porosity of YSZ ceramics prepared by acid leaching of nickel from NiO–YSZ, with 50 wt% NiO, was studied as a function of NiO and YSZ particle size. Significant changes in pore dimension were found when NiO particle size was changed.     

高强度钪铝共掺杂氧化锆电解质材料制备与性能

采用柠檬酸络合法制备了(Sc2O3)0.06(Al2O3)x(ZrO2)0.94–x(x=0,0.005,0.01,0.02)系列电解质材料。通过X射线衍射、扫描电子显微镜、电化学交流阻抗谱和力学性能测试等方法对试样进行了分析,并研究了Al2O3掺杂量对电解质材料性能的影响。结果表明:Al2O3掺杂能很好的促进电解质的烧结,有效的降低晶界电阻并提高其抗弯强度。当Sc2O3和Al2O3掺杂量分别为6%和1%摩尔分数时,800℃时氧离子电导率为0.050 S/cm,室温抗弯强度达912 MPa。采用厚度为120μm该电解质片做支撑的电池在800℃最高功率密度为0.43 W/cm2,且在0.625 A/cm2恒流放电200 h后该电池性能没有衰减。     

沉淀法制备草酸镍对SOFC阳极电性能的影响

以Ni(NO3)2·6H2O为主要原料,氨水为沉淀剂,采用沉淀法制备草酸镍.以草酸镍作为SOFC阳极材料.通过XRD、DTA-TG、SEM和电化学工作站等测试手段分别对粉体物相、热综合分析及电池的结构与电性能进行了表征.研究结果表明,利用沉淀法制备的粉体为单斜晶系的Ni2C2O4·2H2O,以NiC2O4· 2H2O作为阳极材料,具有很高的催化活性,使得单电池在H2燃料气下750℃的开路电压为1.05V,最高功率密度为1.32W/cm2.     

固体氧化物燃料电池阳极研究

作为固体氧化物燃料电池(SOFC)的关键部件之一,阳极性能对SOFC性能有着十分重要的影响.本文主要对阳极研究进展进行综述,重点对阳极组织和性能方面的研究情况进行了阐述,合理选择阳极材料和制备工艺条件,优化阳极微观组织结构是获得高性能阳极的重要方面.对阳极材料选择和制备方法进行了简单的介绍.     

Thin Yttrium-Stabilized Zirconia Electrolyte Solid Oxide Fuel Cells by Centrifugal Casting

A centrifugal casting technique was developed for depositing thin 8-mol%-yttrium-stabilized zirconia (YSZ) electrolyte layers on porous NiO-YSZ anode substrates. After the bilayers were cosintered at 1400°C, dense pinhole-free YSZ coatings with thicknesses of ∼25 μm were obtained, while the Ni-YSZ retained porosity. After La_0.6Sr_0.4Co_0.2Fe_0.8O₃ (LSCF)-Ce_0.9Gd_0.1O_1.95 (GDC) or La_0.8Sr_0.2MnO₃ (LSM)-YSZ cathodes were deposited, single SOFCs produced near-theoretical open-circuit voltages and power densities of ∼1 W/cm² at 800°C. Impedance spectra measured during cell tests showed that polarization resistances accounted for ∼70%–80% of the total cell resistance.     

钙钛矿阳极固体氧化物燃料电池在CO–CO2燃料下的性能和稳定性

以原位析出纳米Co–Fe颗粒的La_0.4Sr_0.6Co_0.2Fe_0.7Nb_0.1O_3–δ(LSCFN)钙钛矿为阳极,考察了直接使用CO–CO₂燃料时的阳极结构演变、单电池电化学性能和稳定性。结果表明:在CO燃料中,ABO₃钙钛矿结构LSCFN转变为A₂BO₄层状钙钛矿结构;在CO中引入少量CO₂后,LSCFN则以单钙钛矿结构为主,并有效抑制了碳沉积。单电池在CO燃料下的最大功率密度可达0.6 W/cm²(850℃),并在n(CO):n(CO₂)=5:1(摩尔比)燃料下运行超过100 h。     

Fabrication of Dense Zirconia Electrolyte Films for Tubular Solid Oxide Fuel Cells by Electrophoretic Deposition

Electrophoretic deposition (EPD) is used to produce zirconia electrolyte films for tubular solid oxide fuel cells. A simple suspension chemistry (8-mol%-yttria-stabilized zirconia particles in acetic acid) yields films of similar quality to those from conventional approaches (such as electrochemical vapor deposition), but at potentially much less expense. A key factor in obtaining high-density, adherent films via the EPD approach is the application of a thin fugitive phase (carbon in this study) on the porous, doped lanthanum manganite cathode tubes prior to zirconia deposition.     

Elastic Properties of Nickel-Based Anodes for Solid Oxide Fuel Cells as a Function of the Fraction of Reduced NiO

The changes in porosity and elastic moduli of YSZ-containing nickel-based anode materials for solid oxide fuel cells were studied as a function of the fraction of reduced NiO. Anode samples were reduced in a gas mixture of 4% hydrogen and 96% argon for different periods of time at 800°C and their Young's and shear moduli were determined afterward at room temperature using resonant ultrasound spectroscopy and impulse excitation. It was found that the magnitude of Young's and shear moduli decreased significantly with increasing fraction of reduced NiO and that the magnitude of the elastic moduli of a fully reduced Ni–YSZ anode was ∼45% lower than that of unreduced NiO–YSZ. Because the elastic moduli of NiO are close to those of Ni, the observed decrease in the magnitude of the elastic moduli was found to be caused mainly by the significant increase in the porosity of the sample as a result of NiO reduction. Expressions are presented for the amount of porosity and the magnitude of the elastic moduli as a function of the fraction of reduced NiO.     

氧化镍薄膜的制备与分析

以硝酸镍为起始原料,采用溶胶-凝胶法制得高稳定性的溶胶体系,用浸镀法在玻璃表面镀膜,研究了不同物质配比对溶胶稳定性和成膜性的影响,利用DTA、IR、XRD分析了凝胶和薄膜的结构,确定了氧化镍薄膜的制备条件;溶胶制备温度为60～80℃,pH=4,镀膜热处理温度为300～350℃,时间2h。