YSZ包覆YDC纳米晶复合固体电解质的制备

研究了YSZ包覆YDC纳米晶复合固体电解质的制备工艺.首先,以分析纯的Ce(NO3)3·6H2O和Y(NO3)3·6H2O为原料,采用沉淀法制备了分散性较好的YDC纳米粉体,然后将其均匀分散于含有分析纯的ZrOCl2·8H2O、Y(NO3)3·6H2O的醇水溶液中,采用溶胶凝胶法制备了ZrO2(Y2O3)包覆CeO2(Y2O3)复合纳米粉体.XRD、TEM、IR分析结果表明经600℃焙烧后的CeO2-Y2O3复合纳米粉体为单一萤石相,晶粒尺寸为15nm左右且分散性良好;成功合成了的YSZ包覆YDC复合纳米粉体,其中反应温度在75℃时粉体的包覆性及其分散性较好.以合成的包覆型纳米粉体为原料,通过常压烧结制备了包覆型YSZ/YDC复合固体电解质.研究表明,在相同保温时间内(2h),随着烧结温度从800℃提高到1350℃,试样相对密度从52%迅速增加95%以上.当烧结条件为从室温升温到1300℃,迅速降温到1250℃保温2h后,烧结体的相对密度可达95%以上,平均晶粒度为100nm左右.     

流延法制备SOFC NiO/YSZ阳极的研究

流延法制备了SOFC NiO/YSZ阳极,比较了NiO(微米级)和NiO(纳米级)两种NiO,发现由NiO(纳米级)制备的电池在800℃最大放电功率密度257.1mW/cm2,而由NiO(微米级)制备的电池相同条件下仅为124.9mW/cm2,原因在于NiO(纳米级)粒径小,制备的阳极三相反应区大.NiO(纳米级)经700℃煅烧后制备的电池最大功率密度增加到369.0mW/cm2,而 800℃和900℃煅烧时减少到169.5和159.0mW/cm2,因为700℃煅烧增加了NiO的活性,而800和900℃煅烧的NiO粒径增大到1.35μm,制备的阳极减小了反应活性区.YSZ在1200℃煅烧后,粒径从0.2μm增加到34μm,由于YSZ粒径远大于NiO,导致NiO之间接触不良,制备的电池性能下降到120.0mW/cm2,继续球磨12h后,YSZ粒径减小到0.70μm,NiO和YSZ之间分布均匀,制备的电池放电功率密度提高到447.9mW/cm2.     

缓冲溶液法制备SOFC用Ni/YSZ负极材料

固体氧化物燃料电池（SOFC）用负极材料Ni/YSZ金属陶瓷的性能与其微观结构密切相关,采用缓冲溶液法制备了三种Ni/YSZ金属陶瓷,并对其相组成,显微结构及电性能进行了表征,分析表明,与机械混俣法相比,缓冲溶液法能够使Ni在YSZ基质中分布更均匀,相应地,在整个测试温度区间内（836－1188℃）,由缓冲溶液法制备了w(Ni)为43％的试样B－43的电导率均远高于由传统的机械混合法制备的同一组成的试样M－43,B－43试样在1000℃的电导率为709．73S．cm^-1,可望用作SOFC的负极材料。     

固体氧化物燃料电池阳极材料的流延制备和电池性能研究

利用流延法制备NiO-YSZ阳极，采用磁控溅射、多层流延法制备YSZ电解质薄膜，丝网印刷制备BSCF-YSZ阴极，制备出Ni-YSZ／YSZ／BSCF-YSZ单电池。阳极制备中探索了浆料配比对生坯性能的影响；研究了不同造孔剂得到的流延阳极的微结构形貌差异。考察了双层流延、磁控溅射制备YSZ薄膜的微观结构，并测试评价了电池性能。     

流延法制备高热导率定向石墨/高分子复合片层材料(英文)

以天然鳞片石墨为原料,PVB为黏结剂,PEG和DBP混合物为增塑剂,通过流延工艺在室温下制备了定向排列的石墨/聚合物片层复合材料。系统分析了不同黏结剂用量和流延刀口高度下复合片层材料的定向排列状况,并探讨了定向排列程度对其热导率的影响。XRD和SEM的结果表明,石墨/聚合物复合片层材料显示了不同程度的定向排列。热导率测试结果表明,片层复合材料的热导率随着定向排列程度的提高而增大。通过优化黏结剂的用量和流延刀口高度制备了具有较高热导率的片层复合材料,其热导率最高可达490 W/(m.K)。     

Properties of Ni/YSZ porous cermets prepared by electroless coating technique for SOFC anode application

A conceptual nickel–yttria stabilized zirconia (Ni/YSZ) cermet has been prepared by coating YSZ particles with metallic nickel using electroless coating technique. Concentration of nickel was varied between 5 and 60 vol%. Bulk samples were prepared by uniaxial pressing followed by sintering in the temperature range 1,200–1,350 °C with a soaking time of 2–6 h. Thorough investigation on the electrical characteristics, thermal expansion behavior of the samples have been performed as a function of Ni-content in the cermet. Thermal expansion behavior and conductivity measurement results suggest that the samples prepared by this technique are suitable for solid oxide fuel cell (SOFC) anode application at Ni concentration as low as 20 vol%.     

Pechini溶胶-凝胶法制备SiO2/TiO2复合微粒

采用超声St(o)ber法制备了单分散性的纳米载体SiO2,再采用Pechini溶胶-凝胶制备法制备出SiO2/TiO2复合微球.通过X射线衍射仪、场发射扫描电子显微镜(FESEM)对粉体的晶型和显微形貌进行测试分析.结果表明:纳米载体SiO2球形颗粒为无定形态,Ti02粉体为形貌多样的块状颗粒,大颗粒粒径大于10μm...     

Sol-Gel法制备钛酸铅涂层碳纤维工艺研究

用三种不同方案制备了钛酸铅（PT）溶胶,并在碳纤维表面制备了PT溶胶涂层。测试了溶胶黏度和稳定性,对纤维涂层的物相进行了XRD分析。实验表明,加入乙酰丙酮能有效地螯合Ti^4＋和控制水解的程度,合成的溶胶宜于长期放置;增加[Ti]^4＋／[Pb]^2＋比值会使溶胶的稳定性降低;溶胶黏度与浓度有相同的增大趋势,但高浓度的溶胶不宜于涂层制备;将溶胶涂于碳纤维表面,在氮气保护下经热处理,XRD检测结果有PbTiO3相存在,可成功制得连续的阿涂层碳纤维。     

YSZ纳米粉料流延成型电解质薄膜性能研究

探索了以YSZ纳米粉体为原料,采用流延成型的方法制备YSZ电解质薄膜的工艺过程,具体探讨了不同粒度粉体流延后坯体的性能,结果表明,纳米范围内颗粒粒度粗可以获得致密度较高的坯体。但在烧结过程中,细粒度粉料表现出更好的性能,实验制备的YSZ电解质薄膜的面积比电阻在1123K,比德国D样品大幅度下降。573～1023K的阻抗谱显示出实验制备的YSZ电解质试样的晶粒、晶界和电极处的阻抗都明显降低,综合性能明显优于国外同类产品。流延成型工艺可以获得尺寸为100mm×100mm×0.125mm的8YSZ电解质薄片,这为平板式SOFC在中国的快速发展做好了材料上的准备。     

GNP法制备固体氧化物燃料电池复合阳极材料CuxCo1-x-SDC的研究

采用甘氨酸-硝酸盐法制备了CuxCo1-xO-SDC复合阳极材料。利用电化学工作站测试了其电化学性能,使用SEM、电导率、红外、差热-热重分析仪对CuxCo1-xO-SDC进行表征。研究结果表明,在Cu基阳极中加入一种具有高催化活性的金属钴,阳极表现出很好的催化活性,提高了电池的电化学性能。     

Preparation of 3YSZ/Cu composite by in-situ chemical route

To improve electrical and mechanical properties of electrodes for contact welding, a 3 mol% yttria stabilized zirconia (3YSZ) to reinforced copper matrix composite was developed by an in-situ chemical process. The microstructure and properties of the in-situ composite were investigated. The results showed that in-situ nano-scale particles were uniformly dispersed in the copper matrix by dispersed nano-particle and its cluster. Due to their reinforcement, the hardness of the in-situ 3YSZ/Cu composite significantly increased. Moreover, the electrical conductivity of the in-situ composite decreased with the increase of 3YSZ content.     

Preparation and properties of W-SiC/Cu composites by tape casting and hot-pressing sintering

In this study, W-SiC/Cu composites were prepared by tape casting and vacuum hot-pressing sintering. The microstructures and properties of the composites were studied by means of X-ray diffraction, X-ray photoelectron spectroscopy, field emission scanning electron microscopy, Vickers hardness test, bending strength test and coefficient of thermal expansion (CTE) test. The results showed that W₂C, WC and WSi₂ formed in the composites. The effects of SiC particle size on the relative densities, Vickers hardness, bending strength and CTE of composites were investigated. Vickers hardness, bending strength and CTE of the composite with SiC particle size of 6?µm reached the optimal values, which were 445.2?HV, 726.1?MPa, 9.24?ppm?K^?1.     

气相溶胶-凝胶法制备TiO_2-硅藻土复合光催化材料

以硅藻土和钛酸四丁酯(TBOT)为原料,氨气气氛中,利用TBOT在硅藻土表面及内部的原位水解-缩合反应制备TiO_2-硅藻土复合光催化材料;采用SEM、XRD、EDS、紫外分光光度计等对该复合材料的表面形貌、晶型、催化性能等进行表征;使用该复合材料对甲基橙进行催化降解。结果表明:TBOT在硅藻土表面及内部生成纳米TiO_2微粒,具有硅藻土的孔道结构和纳米TiO_2微球2级结构,具有光催化性能。     

Powder dispersion and aqueous tape casting of YSZ-NiO composite

Powders of YSZ and NiO were prepared by precipitation of hydroxides, calcination and wet grinding. The dispersion conditions were optimized from zeta-potential and viscosity studies. Aqueous suspensions of both the powders exhibited maximum zeta-potential values in two ranges of pH, 3 to 4 (positive) and 9 to 11 (negative), establishing the feasibility of a dispersion of both oxides together. Viscosity measurements indicated presence of effective dispersion of a 1:1.5 mixture of YSZ:NiO below a solid concentration of 25 volume percent. Aqueous tape cast slurries were formulated using PVA solution as binder and glycerol as plasticizer. The rheological behavior of these slurries (viscosity and visco-elastic parameters) was strongly influenced by slight variation in the solid content. Visco-elastic measurements revealed all the slurries to be predominantly viscous and become more elastic with increasing solid content. Defect free flat tapes could be obtained by casting the slurry with optimum flow characteristics (i.e., pseudoplastic but non-thixotropic) that could be sintered to flat sheets with 80% T.D. (theoretical density) and 20% O.P. (open porosity) at 1450°C. Upon reduction in hydrogen at 1000°C, it formed in to YSZ-Ni composite that retained the same micro structural features of YSZ-NiO.     

钛合金表面电泳沉积法制备YSZ/HAp纳米复合涂层

采用电泳沉积法在钛合金基体上制备了YSZ/HAp纳米复合涂层,用场发射扫描电镜、X射线衍射和能量散射谱对复合涂层HAp外层的表面形貌和晶相、复合涂层的断面形貌及元素组成分布进行分析研究,通过粘结-拉伸实验测定了涂层与基体的结合强度.结果表明YSZ/HAp纳米复合涂层与钛合金基体的结合强度明显高于HAp单一涂层与钛合金基体的结合强度,说明YSZ/HAp的复合缓和了HAp涂层与钛合金基体之间的热膨胀系数失配现象,改善了涂层与基体之间的结合.     

SiO2-PMMA无机-有机复合材料的制备与结构研究

应用溶胶－凝胶技术,采用预掺杂的方法,制备了SiO2-PMMA无机－有机复合材料（ORMOSILS）。应用红外光谱分析、广角X射线衍射、扫描电子显微镜分析、差示扫描分析和热失重分析,对SiO2-PMMA无机－有机复合材料（ORMOSILS）的显微结构进行了研究。结果表明：这种方法制备的SiO2-PMMA无机－有机复合材料（ORMOSILS）,有机物均匀分布在无机物基体中,非晶基体SiO2短程有序畴的大小与一般非晶玻璃短程有序畴的大小基本一致等结论。     

Fabrication and mechanical properties of oriented SiC short-fiber-reinforced SiC composite by tape casting

SiC fiber-reinforced SiC composites with nearly unidirectionally and randomly aligned SiC short fiber were prepared by tape-casting and hot-pressing (HP). Volume fractions of fibers were 10 and 20 vol.%. Three-point bending test was carried out at room temperature. The SiC short-fiber-reinforced SiC composites showed completely brittle fracture for any fiber volume fraction and orientation. The maximum strength increased with increasing sintering temperature regardless of orientation of short fiber. In the unidirectionally and randomly aligned composites sintered at 1700 °C containing 20 vol.% fiber, the maximum bending strength was about 390 and 280 MPa, respectively.     

溶胶-凝胶法制备SiO_2/脂肪酸复合相变材料

采用溶胶-凝胶法制备了SiO2作为载体的脂肪酸复合有机相变材料,脂肪酸在SiO2网络空间内发生相变,在宏观上始终呈现固体粉末状.采用差示扫描量热方法、热重和红外光谱对样品进行了热力学、微相结构分析.实验结果显示出了明显的储放热行为.     

Preparation of inorganic composite materials with an adjustable thermal expansion coefficient by the sol-gel method

Abstracts are not published in this journal This revised version was published online in November 2006 with corrections to the Cover Date.     

Preparation of alumina films by the sol-gel method

This review describes our study on preparation of alumina films by a sol-gel process and their several applications that have been investigated since 1986. Alumina films were prepared from alkoxide or inorganic salt. Both as-prepared alumina films were transparent in ultraviolet, visible and near infrared regions. The alumina from inorganic salt (inorganic alumina) was structureless even after annealed at 300–700°C in air, while the alumina from alkoxide (alkoxide alumina) was in pseudo-boehmite at an annealing temperature lower than 400°C and was in - or -type at 400–700°C. Both alumina films became opaque after annealed at temperatures above 1000°C. The inorganic alumina film annealed at 800°C showed a gas permeability that was influenced by physico-chemical properties of penetrant and alumina. Composite films of alumina and poly(vinyl alcohol) (PVA) were hydrophilic but insoluble in water, and removal of PVA from the composite films by annealing at 600°C led to formation of transparent alumina films. Such properties enabled us to use a counter diffusion method for fabricating -Fe₂O₃-doped alumina films. Alumina films doped with organic dyes such as laser dyes, hole-burning dyes and non-linear optical dyes, which were fabricated by gelation of dye-added alumina sol, exhibited laser emission, hole-spectra and second- or third-harmonic generation properties, respectively. Hydrogenation of alkene was catalyzed by Ni nanoparticles doped alumina films that were prepared by gelation of Ni²⁺ solution-added alumina sol and annealing the Ni²⁺-doped alumina gel in hydrogen gas. Nonlinear optical properties were observed for alumina films doped with CdS, Au and Ag nanoparticles, which were fabricated by gelation of Cd²⁺, HAuCl₄ and AgNO₃ solution-added alumina sols and annealing the Cd²⁺-doped alumina gel in H₂S gas and the Ag⁺- and Au³⁺-doped alumina gels in H₂ gas. Rare earth metal ion-doped alumina films, which were prepared by gelation of rare earth metal ion solution-added alumina sol and annealed the ion-doped alumina gel, exhibited not only normal luminescence but also up-conversion emission, energy transfer type luminescence and long lasting luminescence.