磷灰石型La（9.33）（SiO4）6O2电解质的烧结及性能

在燃烧法制得的磷灰石型LSO电解质纳米粉体基础上,研究了预处理、成型压力、烧结温度和保温时间对LSO烧结体致密度的影响.烧结实验结果表明：球磨预处理和合适的成型压力,可以有效消除颗粒间的团聚、降低烧结温度和提高致密度;最佳成型压力为225 MPa;最佳烧结温度为1 400℃下保温3 h,烧结体的致密度高达96%.运用交流阻抗谱法研究了LSO烧结体的电性能,结果表明：烧结体随温度的升高,晶界电阻逐渐减小,晶粒电阻逐渐占据主导;烧结体电导率与温度的关系符合Arrhenius经验公式,700℃时离子电导率达到4.38×10^-3s/cm.     

中温氧化物燃料电池电解质材料制备和性能研究

中温固体氧化物燃料电池（SOFCs）的工作温度应低于800℃。本文重点对ZrO2基、CeO2基、Bi2O3基和ABO3型电解质材料的最新进展和发展趋势作了综述。以8%氧化钇稳定氧化锆（8YSZ）作为电解质的SOFCs,工作温度在1000℃左右。经较低价的碱土和稀土离子（Sr2＋,Ca2＋,Sc3＋和Y3＋）掺杂稳定ZrO2,在800℃,氧化钪掺杂氧化锆（Zr0.9Sc0.1O1.95,scandia doped zirconia,SSZ）的电导率（0.1S/cm）比Zr0.9Y0.1O1.95（10YSZ）的（0.03S/cm）高得多。薄膜化是改进氧化锆基电解质的电导性能的另一个途径。厚度小于10μm的YSZ基SOFCs,在800℃时功率密度最大可达2W/cm2。研究新的稳定的双掺杂电解质材料将会是CeO2基材料研究的重点。Y2O3和Sm2O3共掺杂（Y0.1Sm0.1Ce0.8O1.9,YSCO）在800℃时电导率可达到0.0549S/cm,电导活化能为0.77eV。Sr和Mg共掺杂LaGaO3（LSGM）阳离子导体已成为中低温SOFCs的重要候选电解质材料。钙钛矿型氧化物是除了Bi2O3以外氧离子电导率最高的陶瓷材料。寻求新的、优良的中温SOFCs电解质材料仍是目前推动中温SOFCs实用化的关键因素之一,薄膜化技术是研究的另一个重点。     

新型中温SOFC阴极Ba_(0.6)Sr_(0.4)Co_(0.9)Nb_(0.1)O_(3-δ)的制备与性能研究

采用固相反应法合成了中温固体氧化物燃料电池(IT-SOFCs)阴极材料Ba0.6Sr0.4Co0.9Nb0.1O3-δ(BSCN)。利用XRD对该材料的结构进行了表征。研究表明,室温下阴极材料BSCN成立方相结构(Pm-3m);将该阴极材料与电解质Ce0.9Gd0.1O1.95(GDC)混合,并在1 000℃煅烧10h后,它们之间无化学反应发生。在SOFCs的操作温度(600～800℃)下,BSCN阴极的电导率可达21～27S/cm。热膨胀测试表明,BSCN的热膨胀系数为17.0×10-6/K,明显低于SrCo0.9Nb0.1O3-δ(SCN)的热膨胀系数,这有利于提高阴极与电解质GDC间的热匹配性。以BSCN作电极,GDC作电解质,制备对称电池BSCN/GDC/BSCN,研究电极与电解质间的极化阻抗。750℃时,极化阻抗仅为0.026Ω.cm2。以BSCN作阴极,NiO-SDC(NiO-Ce0.8Sm0.2O1.9)作阳极,300μm厚的GDC作电解质,制备单电池BSCN/GDC/NiO-SDC。800℃时,单电池的最大功率密度可达782mW/cm2。以上结果表明,BSCN有望成为中温固体氧化物燃料电池阴极的候选材料。     

Effects of Thickness on the Electrical Conductivity of Sputtered YSZ Film with Nanocrystalline Columnar Microstructure

In order to investigate the effect of the thickness on the electrical conductivity of yttriastabilized zirconia(YSZ) film, the nanocrystalline columnar-structured YSZ film with thickness of 0.67-2.52 μm was prepared by magnetron sputtering through controlling the deposition time. All the sputtered films with different thicknesses consist of the main phase of cubic YSZ as well as a small amount of monoclinic YSZ. The thicker films exhibit a typical columnar grain structure based on the fractured cross-sectional SEM observations. The average diameters of columnar grains increase from about 40 nm to 100 nm with the film thickness from 0.67 μm to 2.52 μm according to TEM analysis. The thinnest YSZ film with 0.67 μm thickness shows the highest apparent electrical conductivity in the four films in 400-800 ℃ due to the contribution from the highly conductive film/substrate interfacial region. On the other hand, the real electrical conductivities of YSZ films increase with film thickness from 0.67 μm to 2.52 μm after eliminating the contribution of the film/substrate interface. The increasing film thickness leads to the grain growth as well as the decrement in the volumetric fraction of the resistive columnar grain boundary and a consequent higher real electrical conductivity.     

过渡元素掺杂固体电解质的制备及电性能

为了解决固体氧化物电解质在中温范围（500 ℃～800 ℃）工作电导效果不佳的问题,采用燃烧合成方法以氧化镧及过渡离子氧化物为原料,制备了过渡金属元素掺杂的硅酸镧体系电解质材料. 用X-射线衍射图谱、扫描电子显微镜以及红外光谱对所得电解质进行了物相和显微结构分析. 研究表明,掺杂离子对电解质的物相结构及形貌影响很小,但是通过引入适量过渡掺杂离子,能够有效提高电解质的电导率. 当掺杂量摩尔比x=1.0时,锌掺杂后硅酸镧电解质具有最高的离子电导率,在500 ℃时的电导率可达2.106×10-2 S/cm. 相比于未掺杂电解质在500 ℃电导率为1.71×10-3 S/cm有了显著提升. 元素铜的掺入对电解质的致密度有促进作用,压片和二次烧结后电解质的密度达94.1%. 同时通过交流阻抗测试分析证实镍在硅位掺杂会降低电解质的电导率.     

中温固体电解质Ce_(0.8)Gd_(0.2-x)Y_xO_(2-δ)(x=0,0.05,0.10)的制备与性能研究

用溶胶-凝胶法合成了固体电解质Ce0.8Gd0.2-xYxO2-δ(x=0,0.05,0.10).用X射线衍射谱、拉曼光谱分析了样品的微观结构,用交流复阻抗谱研究了样品的电学性能.结果表明:800℃焙烧的所有样品均为具有氧缺位的单相立方萤石结构,晶胞参数随钇(Y)掺杂量增加而减小.钇掺杂量x=0.05的样品Ce0.8Gd0.15Y0.05O2-δ的电导率最高,导电活化能最小,(σ700℃=5.58×10-3S·cm-1,Eα=0.92 eV),高于未掺杂Y的Ce0.8Gd0.2O2-δ样品的电导率(σ700℃=5.38×10-3S·cm-1Eα=1.09 eV).说明适量双掺杂Y提高了Ce0.8Gd0.2-xYxO2-δ的电导率并且降低了其活化能.     

电解质掺杂Na2SO4对固体氧化物燃料电池性能的影响

以不同含量的Na2SO4掺杂YSZ（Y2O3稳定的ZrO2,Y2O3的摩尔分数为8％）为复合电解质,Co3O4为阳极催化剂,La0.7Sr0.3MnO3为阴极催化剂,组装固体氧化物燃料电池,以二氧化硫气体为燃料气,测试复合电解质材料电池的电化学性能.结果表明：以质量分数为25％的Na2SO4＋YSZ为复合电解质的电池在700℃时,获得最大开路电压372mV,功率密度7.87mW·cm-2.以不同含量的Na2SO4掺杂YSZ作为复合电解质时,电池的电流密度和功率密度的高低顺序均为：质量分数25％的Na2SO4＋YSZ＞质量分数16％的Na2SO4＋YSZ＞质量分数8％的Na2SO4＋YSZ＞质量分数50％的Na2SO4＋YSZ＞YSZ.     

Ce_(1-x)Ho_xO_(2-δ)(x=0.05～0.3)固体电解质的性能研究

利用溶胶-凝胶法合成固体电解质Ce1-xHoxO2-δ(x=0.05～0.30),采用X-射线衍射仪(XRD)、拉曼光谱仪(Raman)、原子力显微镜(AFM)对样品的结构进行表征,利用交流阻抗谱测试掺杂稀土Ho对其电性能的影响.XRD结果表明:800℃焙烧的所有样品均为单相立方萤石结构,Raman光谱表明:Ce0.85Ho0.15O2-δ具有氧缺位的萤石结构,AFM照片显示Ce0.85Ho0.15O2-δ致密度较好,阻抗谱结果表明:掺入Ho3+提高了Ce1-xHoxO2-δ的电导率,Ce0.85Ho0.15O2-δ的电导率最高,活化能最小,600℃时的电导率为0.016 S·cm-1,活化能为0.92 eV,比未掺杂的CeO2的电导率提高了4个数量级.     

钐和锌双掺杂La9.33（SiO4）6O2电解质的制备及其电导率

为提高磷灰石型电解质（LSO）的电导率,以氧化镧（La₂O₃）、氧化锌（ZnO）和氧化钐（Sm₂O₃）为主要原料通过尿素-硝酸盐燃烧法在600 ℃的温度下合成了掺杂钐和锌的La_9.33Sm_xSi₅ZnO_{（25+1.5x）}固体电解质粉末。采用X射线衍射、扫描电子显微镜、变温介电测量系统对样品进行物质结构、表面形貌、电导率的表征。研究了不同温度和不同掺杂浓度下La_9.33Sm_xSi₅ZnO_{（25+1.5x）}的电导率。结果表明,Sm和Zn成功掺杂进入LSO的晶格中,样品具有典型的P6₃/m磷灰石结构且纯度高,LSO的形貌未改变。当Sm掺杂浓度为0.6,Zn掺杂浓度为1时,在温度为650 ℃下La_9.33Sm_xSi₅ZnO_{（25+1.5x）}的电导率达到1.50×10^-3 S/cm;确定了最佳烧结温度为1 400 ℃。La_9.33Sm_xSi₅ZnO_{（25+1.5x）}的电导率在同一温度下随着掺杂量的增加先提高后降低,掺杂样品的晶胞参数相比于未掺杂样品的晶胞参数增大,活化能随着掺杂量的增大先降低后升高。此外La_9.33Sm_xSi₅ZnO_{（25+1.5x）}的电导率在同一掺杂量下,随着温度的升高而提高。     

Comparison of effective parameters for copper powder production via electrorefining and electrowinning cells and improvement using DOE methods

The influences of cupric ion concentration (5-35 g/L),current density (500-2000 A/m2),circulation rate of the electrolyte solution (15-120 mL/min),and temperature (25-60℃) on the physical and chemical properties of copper powders obtained in electrolysis cells were investigated.Two industrial processes,electrorefining (ER) cells with a synthetic electrolyte and electrowinning (EW) cells with an original solution of coppermineral leaching,were utilized to produce copper powders.Finally,the statistical full f...     

半导体器件金属化热电徙动的温度测试

在金属化布线电徙动试验中，采用金属薄膜电阻测温法精确测量了样品的局部温度，在环境温度为150℃，电流密度为3×106A／cm2和5×106A／cm2时，金属薄膜温度分别高于环境温度32．5℃和100℃；提出了扩散电阻测温法，在电徙动试验中精确测量并适时监控样品局部温度，从而实现了电流密度指数因子动态测试．     

退火温度对Al掺杂ZnO薄膜结构和性能的影响

采用直流磁控溅射技术,在玻璃衬底上制备了ZnO:Al(ZAO)薄膜样品。其他参数不变,在不同的温度下对样品进行了退火处理,研究了薄膜的结构性质、电学和光学性质随退火温度的变化关系。实验结果表明:在退火温度为200℃时,ZAO薄膜具有较优的光电性能,其电阻率为9.62×10-5.cm,可见光区平均透射率为89.2%。     

磁控溅射CdTe薄膜的光电学特性

采用射频磁控溅射方法在玻璃和Si(111)衬底上制备了碲化镉(CdTe)薄膜,并研究了溅射功率对薄膜的结构、光学和电学性能的影响.X射线衍射分析表明,所有样品均沿(111)面择优取向; 平均晶粒尺寸随溅射功率的增加而增加,即从73.0 nm(70 W)增加到123.6 nm(110 W).紫外 - 可见 - 近红外光谱分析表明, CdTe薄膜在可见光范围内具有较高的吸光度; 薄膜的带隙随着溅射功率的增加而减小,最小值为1.38 eV.CdTe薄膜的导电性随溅射功率的增加而明显增强,当溅射功率为110 W时电阻率仅为21.5 Ω?cm.该研究结果可为制备高导电性和高吸收率的半导体薄膜提供参考.     

Fabrication and characterization of composite YSZ-La9.33Si6O26 oxygen-ion conductor

To improve the conductivity of Y₂O₃-stabilized ZrO₂ (YSZ) based oxygen-ion conductor, Zr_0.85Y_0.15O_1.925-La_9.33Si₆O₂₆ (YSZ-LSO) composite ceramics with the mass fraction of La_9.33Si₆O₂₆ (LSO) of 15% were prepared by using a modified coprecipitation method. The phases, microstructures and conductivities of the YSZ, LSO and YSZ-LSO were investigated by X-ray diffraction, electron microscopy and complex impedance, respectively. The results show that the as-calcined powder of YSZ-LSO composite has the grain size less than 10 nm, and the as-sintered composite ceramics are composed of YSZ and LSO phases. The conductivity can be enhanced obviously by composite method. At 700 °C, the conductivity of the composite ceramic is 0.125 S/cm, which is one order in magnitude higher than that of the YSZ ceramic and two orders in magnitude higher than that of LSO ceramic. By analyzing the impedance spectra and modulus spectra, the interfacial effect on the conductivity improvement was proposed.     

梯度掺杂AZO薄膜的制备及其性能表征

采用Sol-Gel法,以不同铝离子浓度的溶胶梯度掺杂的方法制备了Al掺杂ZnO（AZO）薄膜,用XRD衍射仪和SEM扫描电镜对该薄膜进行了结构和形貌分析,并对其电学性能和光学性能进行了研究。结果表明,梯度掺杂的AZO薄膜比单一浓度掺杂5.0 at%（原子数百分比）的薄膜具有更明显的c轴择优取向,更强的本征紫外发光峰和近紫外发光峰。当薄膜的退火温度在500~650℃区间时,薄膜电阻率稳定在10-2Ω.cm,高于700℃时,薄膜电阻率明显升高。     

碱土金属双掺杂铁钴酸镧的制备和表征

柠檬酸法制备了La0.7Ba0.15E0.15Fe0.8Co0.2O3(LBEFC,E=Sr,Ca)系列阴极材料,利用XRD、SEM对LBEFC晶体结构、微观形貌进行分析,采用四探针法测试了LBEFC的电导率。实验结果表明,1 000℃煅烧2 h,LBEFC可以形成单一的畸变钙钛矿结构,LBEFC衍射峰较LaFeO3衍射峰向右偏移,晶胞参数a、b减小,c增大。La0.7Ba0.15Sr0.15Fe0.8Co0.2O3和La0.7Ba0.15Ca0.15Fe0.8Co0.2O3晶胞体积膨胀率分别为43.5%、42.7%,晶格畸变主要发生在(200)、(211)晶面方向。在300~800℃,LBEFC电导率均大于100 S/cm,满足中温固体氧化物燃料电池阴极材料的要求。LBEFC与新型电解质Ce0.8Sm0.2O2在1 200℃下烧结5 h,没有新相生成,具有良好的相容性。     

PEI-PEO基全固态电解质的性能

聚氧乙烯(PEO)基全固态复合电解质可作为高能全固态锂电池的电解质膜材料.采用溶液浇铸法,以PEO为基质,LiC1O4为锂盐,聚乙烯亚胺(PEI)和柠檬酸(CA)及无机纳米粉体(NCA)做性能改进剂,制备PEI-PEO-LiC1O4-CA-NCA全固态复合聚合物电解质(SCPE)膜,对其进行X射线衍射(XRD)表征和交...     

Preparation,crystallization,and wetting of ZnO-Al_2O_3-B_2O_3-SiO_2 glass-ceramics for sealing to Kovar

A novel type of ZnO-Al2O3-B2O3-SiO2 glass-ceramics sealing to Kovar in electronic packaging was developed,whose thermal expansion coefficient and electrical resistance are 5.2×10-6/oC and over 1×1013 Ω·cm,respectively.The major crystalline phases in the glass-ceramic seals were ZnAl2O4,ZnB2O4,and NaSiAl2O4.The dielectric resistance of the glass-ceramic could be remarkably enhanced through the control of alkali metal ions into crystal lattices.It was found that crystallization happened first on the surface o...     

The Properties of YSZ Electrolyte Sintering at 1300 ℃

The properties of yttria stabilized zirconia（YSZ） related to the sintering process were discussed.YSZ nano-powders about 40-100 nm as raw material,the sub-micrometer grain sizes such as 0.4-3 μm in YSZ were gotten by sintering process at 1300 ℃,which was performed at 1000 ℃ for 2 h,then raised the temperature at the rate of 50 ℃ / h to 1400 ℃,then decreased directly to 1300 ℃ in 30 minutes,finally at 1300 ℃ for 5-20 hours.The ratio of bigger grain size becomes larger as the holding time increasing at 1300 ℃.The grains less than 1 μm are about 50%,eg,43.2%,52.2% and 51.1% related to 1300 ℃ holding 5 hours,8 hours and 10 hours,respectively.As YSZ grain size became small,the electrical conductivities did not decrease,even increased,about 0.20 s/cm at 1000 ℃.The reduced sintering temperature and time were benefited to co-fire with the electrodes in electrode-supported SOFCs.     

矿化剂对莫来石质偏转磁芯承烧座性能的影响

以电熔莫来石颗粒、莫来石细粉以及生粘土为主要原料,α-A l2O3微粉和矿化剂Mg-CO3、CaCO3、BaCO3为添加剂,经配料、混练、成型后,在1 460℃保温3 h条件下烧成,合成出莫来石质偏转磁芯承烧座,并检测试样吸水率、显气孔率、体积密度及烧后线变化率,同时进行显微结构分析。研究了单独添加MgCO3、CaCO3、BaCO3以及三种矿化剂两两复合对莫来石质偏转磁芯承烧座性能的影响,结果表明：使用MgCO3、CaCO3、BaCO3三种矿化剂均能起到矿化作用,改善制品的烧结性能,从单种加入来看,以添加3%BaCO3的矿化效果最好,其体积密度2.20 g/cm3为最高、显气孔率28.7%为最低,明显提高了试样的烧结性能。复合加入以添加3%BaCO3和3%CaCO3的7#试样效果更为明显,其显气孔率最低,体积密度最大,烧结程度最好,这有利于提高承烧座的抗热震性和使用寿命.