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1.
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.  相似文献   

2.
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La9.33SmxSi5ZnO(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La9.33SmxSi5ZnO(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La9.33SmxSi5ZnO(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 ℃。La9.33SmxSi5ZnO(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La9.33SmxSi5ZnO(25+1.5x)的电导率在同一掺杂量下,随着温度的升高而提高。  相似文献   

3.
Cu/(10NiO-NiFe2O4) cermets containing mass fractions of Cu of 5%, 10%, 15% and 20% were prepared, and their electrical conductivities were measured at different temperatures. The effects of temperature and content of metal Cu on the electrical conductivity were investigated especially. The results indicate that the metallic phase Cu distributes evenly in 10NiO-NiFe2O4 ceramic matrix. The mechanism of electrical conductivity of Cu/(10NiO-NiFe2O4) cermets obeys the rule of electrical mechanism of semiconductor, the electrical conductivity for cermet containing 5% Cu increases from 2.70 to 20.41 S/cm with temperature increasing from 200 to 900 ℃. The change trend of electrical conductivity with temperature is similar with each other and it increases with increasing temperature and content of metal Cu. At 960 ℃, the electrical conductivity of cermet increases from 2.88 to 82.65 S/cm with the content of metal Cu increasing from 0 to 20%.  相似文献   

4.
The effect of [S] on strength and toughness of low alloy steel plates in which sum of [P], [N], T[O] is less than 8x10 5 and the effect of T[O] on strength and toughness of the steel plates in which sum of [S], [P], [N] is less than 7x10~5 were investigated. It is found that the strength of the steel plates decreases with increasing [S] content when [S] is less than 4x10~5. When [S] varies within the range of 4×10~(-5)-1.2×10~(-4), [S] has no significant effect on strength of the steel. The strength of the steel plates increases with increasing T[O] content when T[O] is less than 30×10~(-6), but decreases with increasing T[O] when T[O] is more than 3×10~(-5). The difference between the LETT in plate length direction and LETT in width direction decreases with decreasing [S] content. However, even when [S] is decreased to 9×10~(-6), the difference of the LETT is still 16℃. When T[O] varies between 1.8×10~(-5) and 5.2×10~(-5), the low temperature impact toughness of the steel plates slowly decrease  相似文献   

5.
为了解决干旱荒漠区的深部找矿问题和探索地电化学法在干旱荒漠区寻找隐伏金属矿床的可行性,在甘肃白银银硐沟勘查区运用地电提取、土壤离子电导率等多种找矿方法来找寻隐伏的矿体。以9×10^-6、18×10^-6、36×10^-6三级浓度分带划分,圈出22个地电提取cu异常;以7.25×10^-6、14.5×10^-6、29×10^-6三级浓度分带划分,圈出32个地电提取Zn异常;以100、200、400uS/cm三级异常强度分带划分,圈出11个电导率异常。按照异常的规模、大小、强弱、变化、吻合程度、异常出现的地质部位等因素,将测区内的综合异常划分为两类5个综合异常靶区,其中1类靶区2个,Ⅱ类靶区3个。  相似文献   

6.
A series of bi A-SPAES(Ds=0.4)/phosphotungstic acid(PWA/bi A-SPAES)composite membranes with various contents of PWA were prepared and characterized by FT-IR.Scanning electron microscopy(SEM)images indicated the PWA were well dispersed within polymer matrix.These composite membranes were evaluated for proton exchange membranes(PEM)in direct methanol fuel cell(DMFC).These membranes showed good thermal stability.It was found that the water uptake of these membranes increased with the increase of the PWA content in the hybrid membranes.Meanwhile,the introduction of inorganic particles increased both the proton conductivity and the methanol permeability.The proton conductivities of composite membranes were increased from 0.017 S/cm to 0.045 S/cm at 20 ℃ and from 0.054 S/cm to 0.093 S/cm at 100 ℃ with the increase of PWA content from 0 to 50 %.Especially,all the methanol diffusion coefficients(4.20×10-8-1.05×10-7cm2/s)of bi A-SPAES/PWA hybrid membranes are much lower than that of Nafion 117 membrane(2.1×10-6 cm2/s).Bi A-SPAES/PWA hybrid membranes were therefore proposed as candidates of material for PEM in DMFC.  相似文献   

7.
采用扫描电镜(SEM)、X射线衍射仪(XRD)、电子能谱(EDS)分析Cu-Te-Cr合金时效析出相的形貌与组成,研究合金元素对Cu-Te-Cr合金时效组织与性能的影响。结果表明,时效过程中Te、Cr以多元化合物或细小的单质Cr析出,合金的硬度明显升高,随时效温度的升高,Cr粒子长大,共格度降低;同时基体晶粒内,部分析出相重溶,使合金硬度下降;由于Cr和Te两种元素互不相溶,其交互作用生成CrxTey化合物,随着Te含量的增加,铸造过程中生成这种化合物越多,减少Cr元素在铜基体的固溶度,从而合金硬度下降,而导电率有所提高。  相似文献   

8.
采用机械球磨加固相烧结法合成Mn3(Cu0.6Si0.15Ge0.25)N/Ag复合材料。在77K-300K温度范围内,分别研究了Mn3(Cu0.6Si0.15Ge0.25)N/Ag复合材料的热膨胀性能,电导性能和热导性能。当含Ag量分别为1,5,10和20 wt%时,所有样品在有效的温度区间205K-275K表现出负热膨胀。随着Ag含量的增加,有效温度区间向室温方向移动。另外,和Mn3(Cu0.6Si0.15Ge0.25)N材料相比,Mn3(Cu0.6Si0.15Ge0.25)N/Ag复合材料具有更高的电导率1?0-6(Ohm.m)-1和热导率10.5W/(mK)。  相似文献   

9.
A mathematical model for describing the relationship between electrical conductivity and the thickness of bilayer, ratio of sublayer thickness of a nano-scale multilayer material (MLM) is presented. Fe/Cu MLM was synthesized by electron beam physical vapor deposition (EB-PVD) technique, and the dependence of electrical conductivity of Fe/Cu MLM on the bilayer thickness and ratio of sublayer thickness were investigated. It is shown that the electrical conductivity of Fe/Cu MLM with fixed ratio of sublayer thickness decreases sharply when the thickness of bilayer becomes thinner than 30 nm. When the bilayer thickness is kept constant, the electrical conductivity linearly decreases with the increasing ratio of sublayer thickness. The values of parameters in the model were obtained by fitting the measured results of electrical conductivity of Fe/Cu MLM with fixed ratio of sublayer thickness. It is found that the calculated values agree well with measured ones.  相似文献   

10.
采用固相法制备Al/Y_2W_3O_(12)复合材料,研究了Al与Y_2W_3O_(12)以不同质量比合成样品的特性。X射线衍射表明:样品只含有Al和Y_2W_3O_(12),不存在Al对Y的取代。SEM和EDS分析表明:小颗粒Y_2W_3O_(12)嵌入在块状Al基底中,为嵌入式复合结构。热膨胀性能和电导率测试分析表明:当Al与Y_2W_3O_(12)的质量比7∶3时,Al/Y_2W_3O_(12)样品的线膨胀系数14.76×10-6/K(RT~600℃)约为Al的一半,呈现良好的导电性,其导电率为18.2 S/m可达Al的电导率的1/2,且Al/Y_2W_3O_(12)样品几乎不表现出吸水性。研究认为,该复合材料具有低膨胀和较高导电性是由于其特有的嵌入式结构所致。  相似文献   

11.
采用软膜板自组装方法,以甲基橙为软模版、过硫酸铵为氧化剂,在酸性条件下合成聚苯胺。探究了反应温度、加料顺序对聚苯胺的微观形貌与导电性能的影响。利用傅里叶变换红外光谱、扫描电子显微镜、X射线衍射表征所得到具有一维纳米结构聚苯胺的结构与微观形貌,并且对其进行了电导率测试。实验结果表明,在低温下,先加入过硫酸铵,再加入苯胺单体,可得到长度达到6 μm、电导率达到8.67×10-1 S/cm的一维纳米结构聚苯胺。  相似文献   

12.
Graphene(Gr)has unique properties including high electrical conductivity;Thus,graphene/copper(Gr/Cu)composites have attracted increasing attention to replace traditional Cu for electrical applications. However,the problem of how to control graphene to form desired Gr/Cu composite is not well solved. This paper aims at exploring the best parameters for preparing graphene with different layers on Cu foil by chemical vapor deposition(CVD)method and studying the effects of different layers graphene ...  相似文献   

13.
通过固相法制备了1.5Li2O-P2O5-xTiO2(x=0.1、0.2…0.9)玻璃以及微晶玻璃快离子导体。对制备的玻璃以及微晶玻璃分别进行了交流阻抗和充放电电化学性能等测试。结果表明,1.5Li2O-P2O5-xTiO2微晶玻璃导电率比对应的玻璃导电率要高,最高为1.77×10^-6S/cm,二者的导电率都随TiO2含量的增加而增加,而且1.5Li2O-P2O5-xTiO2微晶玻璃作为锂离子电池负极充放电性能比对应的玻璃充放电性能要好,但是二者总体充放电性能不佳,最高首次放电比容量为283 mAh g^-1。  相似文献   

14.
为了研究Mn替代Ni对AB3.5型储氢合金结构及电化学性能的影响,采用电弧炉熔炼制备LaNi3.15-xMnxCo0.25Al0.1合金。采用XRD、SEM等材料分析方法以及恒电流充放电等电化学测试技术,研究LaNi3.15-xMnxCo0.25Al0.1(0≤x≤0.3)合金的结构和电化学储氢性能。结果表明:LaNi3.15-xMnxCo0.25Al0.1(0≤x≤0.3)合金由多相组合形成,合金的主相为LaNi5和La2Ni7;随着Mn替代Ni含量的增加,LaNi5相中a轴和c轴以及晶胞体积增加;合金电极的最大放电容量有所升高,由x=0的238mA·h/g逐渐增加到x=0.3的277.1mA·h/g;高倍率性能随着Mn含量的增加先升高后降低,在x=0.2时合金的高倍率性能最佳。  相似文献   

15.
合成了两性离子修饰的氧化石墨烯(ZC-GO),以聚苯并咪唑(PBI)为基体,ZC-GO为质子载体制备了PBI/ZC-GO复合质子交换膜,由于对氧化石墨烯(GO)表面进行了修饰,使得改性石墨烯形成了疏水-亲水结构.测试了复合膜的FT-IR、SEM、吸水率、离子交换容量和质子电导率等性能.结果表明:该质子交换膜具有良好的热稳定性和较高的电导率,在100%相对湿度,80℃时,复合膜(ZC-GO含量为10%)的电导率达到2.2×10-2 S/cm.与纯的PBI膜相比,PBI/ZC-GO复合膜的吸水能力显著提高;其甲醇渗透率为(3.16~7.23)×10-7 cm2/s,虽然与纯PBI膜相比稍有增加,但仍大大低于Nafion膜的甲醇渗透率,有望应用于直接甲醇燃料电池中.  相似文献   

16.
为了满足铝合金架空输电导线的使用需求,以热挤压法制备的Al-Mg-Si合金电工铝杆为研究对象,通过调节Cu元素的添加量,研究了Cu对Al-Mg-Si合金的力学性能及导电率的影响.结果表明,向Al-0.35Si-0.45Mg-0.13Fe合金中添入微量Cu元素后,Mg2Si析出相得到细化且时效强度提高.随着Cu元素含量的增加,峰时效时间缩短,合金抗拉强度不断提高,但伸长率逐渐降低.当Cu含量为0.06%时,合金抗拉强度达到最大值145.7 MPa.合金导电率随着Cu元素含量的增加先升后降,当Cu含量为0.03%时达到最大值60.18%IACS.  相似文献   

17.
The microstructure and the electrical, thermal, friction, and mechanical properties of Cu/Ti2AlC fabricated by hot-pressing at 900 °C for 1 h were investigated in the present work. Microstructural observations have shown that the plate-like Ti2AlC grains distribute irregularly in the network of Cu grains, and well-structured, crack-free bonds between the layers. With the increase in the content of Ti2AlC from layer A to layer D, the electrical resistivity increases from 1.381×10-7 Ω·m to 1.918 ×10-7 Ω·m, the hardness increases from about 980.27 MPa to about 2196.01 MPa, and the friction coefficient from above 0.20 reduces to about 0.15. Oxidation rate increases with the increases of temperature. Exfoliation was obviously observed on the surface of oxidation layer A. The surface of layer D was still intact and the spalling and other defects were not found. The mass decreases in the acid solution, and increases in the alkaline solution. The largest corrosion rate is found in 6.5% HNO3 or 4% NaOH solution.  相似文献   

18.
针对LiTi2(PO4)3基固态电解质电导率低的问题,采用浙江三门高岭土矿作为主要原料,以高温固相法制备铝、镁、硅共掺杂钠超离子导体(NASICON)型快离子导体Li1+2x+2yAlxMgyTi2-x-ySixP3-xO12.研究掺杂比例、温度对固态电解质离子电导率的影响.结果表明,组成为Li1.8Al0.1Mg0.3Ti1.6Si0.1P2.9O12固体电解质在423 K时有最高离子电导率7.86×10-4 S·cm-1.以该组成固态电解质为基片,喷雾热解原位制备Al/ Li1+xV3O8/ Li1.8Al0.1Mg0.3Ti1.6Si0.1 P2.9O12 /C全固态电池并在1.8~3.9 V电压区间进行50次充放电测试.该电池具有较好的稳定性及循环容量保持能力.30次循环以后放电容量基本稳定在190~205 mAh·g-1之间,充放电效率大于90%.  相似文献   

19.
BN/聚砜导热绝缘复合材料的制备及性能   总被引:1,自引:0,他引:1  
采用粉末混合法制备了BN/聚砜导热绝缘复合材料,用扫描电子显微镜(SEM)、导热系数测试仪和超高电阻微电流测试仪对复合材料的微观形貌、导热性能和电绝缘性能进行了表征。结果表明:硅烷偶联剂改性处理后的BN粉体与聚砜基体之间的相容性较好;BN/聚砜复合材料的导热系数随BN含量的增加而增大,最大可达2.08(W·m^-1·K^-1);表面电阻率和体积电阻率随BN含量的增加而减小,最低值分别为0.82×10^15Ω和1.78×10^15(Ω·cm),具有电绝缘性。  相似文献   

20.
Bi0.5Sb1.5Te3/Cu core/shell powders were prepared by electroless plating and hydrogen reduction, and then sintered into bulk by spark plasma sintering. After electroless plating, with increasing the Cu content, the electrical conductivity keeps enhancing significantly. The highest electrical conductivity reaches 3341S/cm at room temperature in Bi0.5Sb1.5Te3 with 0.67wt% Cu bulk sample. Moreover, the lowest lattice thermal conductivity reaches 0.32 W/m·K at 572.2 K in Bi0.5Sb1.5Te3 with 0.67wt% Cu bulk sample, which is caused by the scattering of the rich-copper particles with different dimensions and massive grain boundaries. According to the results, the ZT values of all Bi0.5Sb1.5Te3/Cu bulk samples have improved in a high temperature range. In Bi0.5Sb1.5Te3 with 0.15wt% Cu bulk sample, the highest ZT value at 573.4 K is 0.81. When the Cu content increases to 0.67wt%, the highest ZT value reaches 0.85 at 622.2 K. Meanwhile, the microhardness increases with increasing the Cu content.  相似文献   

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