【作者】 张小珍；

【导师】 刘杏芹； 周健儿；

【作者基本信息】 中国科学技术大学 ， 材料学， 2010， 博士

【摘要】 陶瓷膜与有机聚合物膜相比,具有耐高温、耐化学腐蚀、机械强度高、孔径均匀分布窄、微观结构可控、使用寿命长等独特优点,可以满足特别苛刻的使用要求,在石油化工、化学工业、冶金工业、食品工业、环境工程、新能源等领域有着广泛的应用前景,因而日益受到重视。陶瓷膜技术的应用对节能减排和实现绿色生产,促进社会经济可持续发展具有重要的作用。虽然陶瓷膜及其分离技术在过去的二十年得到迅速的发展,但传统的陶瓷膜一般为平板或多通道管式膜,仍存在许多制约其发展的关键瓶颈,主要有：(1)膜的装填密度低,单位体积有效过滤面积小,分离效率低；(2)制造周期长,工艺过程复杂,制造成本高；(3)膜品种和功能单一,商品化陶瓷膜主要为Al2O3膜,无法满足纷繁复杂的应用需求。近年来,新型中空纤维构型陶瓷膜(外径<2mm)受到广泛关注,中空纤维陶瓷膜除具有传统的陶瓷膜本身优点以外,还具有装填密度大、单位体积膜有效分离面积大、节省原料、设备小型化、结构简单化等特点。溶液相转化法在中空纤维陶瓷膜制备中的应用,可实现通过一步成型制造具有非对称结构和自支撑成膜的复合陶瓷膜,有望大大提高膜分离性能、简化膜制备工艺和显著降低制造成本。因此,研究开发各种新型中空纤维陶瓷膜具有解决长期以来制约陶瓷膜技术发展的瓶颈的巨大潜力。但目前,中空纤维陶瓷膜的研究尚处于起步阶段,仍缺乏相转化法中空纤维陶瓷膜制备与应用相关基础研究。为推动中空纤维陶瓷膜的产业化应用,本课题以Y2O3稳定ZrO2(YSZ)为膜材质,进行了相转化法中空纤维陶瓷膜制备技术研究,发展了相应的中空纤维膜结构与性能表征技术(第二章)；制备了具有梯度多孔结构的低成本堇青石中空纤维陶瓷微滤膜(第三章)和不同微观结构低成本、高渗透性的莫来石中空纤维陶瓷膜(第四章)；将相转化法应用于微管陶瓷膜燃料电池(CMFC)的NiO/YSZ中空纤维阳极制备,发展了以氧化还原稳定的(La0.75Sr0.25)Cr0.5Mn0.5O3 (LSCM)和具有良好化学稳定性的(Pr0.5Nd0.5)0.7Sr0.3MnO3-δ(PNSM)为阴极的微管CMFC,其中温性能可达到实用化水平(第五章)。本论文工作取得的主要成果和创新点归纳如下：1.非对称YSZ中空纤维陶瓷膜制备研究YSZ陶瓷具有机械强度高和优异的耐腐蚀性能等,是重要的陶瓷膜材料之一。但目前还未见商品化的全YSZ非对称(复合)陶瓷膜,其原因在于需采用粒径大于10μm的YSZ粉制备膜支撑体,烧结温度高(≥1600℃),将导致膜制造成本显著提高。因此一般采用YSZ微粉(<1.5μm)在Al2O3支撑体上制备分离膜层的方法获得YSZ/Al2O3复合陶瓷膜,但两者热膨胀系数差别大,且Al2O3的耐腐蚀性能(尤其是耐碱腐蚀性能)相对较差,将影响陶瓷膜的使用寿命和性能。本工作采用相转化法,通过干/湿法纺丝一步成型和一次高温烧成制备了非对称的YSZ中空纤维陶瓷膜。系统研究了铸膜浆料固含量、芯液和外凝固浴组成等对YSZ中空纤维陶瓷膜制备过程中相转化过程和相应的膜微观结构与性能的影响,以期为相转化法中空纤维陶瓷膜的微观结构与性能调控提供相关制备科学研究基础。研究表明,浆料YSZ含量、芯液和外凝固浴组成变化都可明显改变分相动力学条件,形成不同微观结构的中空纤维陶瓷膜。铸膜浆料中YSZ含量增大,导致粘度提高,将抑制分相过程。以水为芯液和外凝固浴,当浆料YSZ含量为50%时,中空纤维膜呈现典型的三明治结构,即中间为海绵状多孔层,而内外两侧为小指孔结构层；固含量为60%-65%时,形成具有外部海绵状层和内部大指孔结构的陶瓷膜。固含量的增大也明显提高了烧结后陶瓷膜海绵状层的致密度,使膜抗弯强度增大而纯水通量降低。芯液与聚合物的溶解度参数值差越大,芯液的胶凝能力越强,湿膜越容易通过瞬时分相形成指孔结构和致密的内皮层。芯液中加入溶剂N-甲基吡咯烷酮(NMP)后,其胶凝能力明显下降,湿膜内部分相过程受到抑制,倾向于形成多孔结构的内表面,且从外部产生的指孔将更易向内部扩展；芯液中NMP含量越高,膜孔隙率和外皮层平均孔径越大,膜的纯水渗透通量越高,尤其是NMP含量达到90vol%以上时,可形成高度非对称结构的YSZ中空纤维膜,大的指孔可贯穿至内表面开口,内表面呈高度多孔结构,从而显著降低了膜的渗透阻力。采用纯NMP为芯液制备的YSZ中空纤维膜,经1320℃保温5h烧结后,其外表分离层平均孔径为0.58μm,纯水通量高达16.34 m3/(m2-h-bar),为以纯水作芯液时的3.91倍。芯液中NMP含量增大时,YSZ中空纤维膜孔隙率的增大和大指孔的形成也相应明显降低了其抗弯强度。以弱胶凝剂一乙醇代替强胶凝剂一水作为外凝固浴,并以水为芯液,可成功制备高渗透性多孔YSZ中空纤维陶瓷膜。制备的YSZ膜呈现特殊的高度非对称结构,主要由外部薄的海绵状多孔分离层和大的指孔结构形成的支撑层构成,且其内表面比外表面更为多孔和具有更大的平均孔径。中空纤维陶瓷膜的微观结构对其渗透阻力具有极其重要的影响,与水相比,以乙醇为外凝固浴时制备的YSZ中空纤维膜,其纯水渗透通量显著提高,表现出更低的流体渗透阻力；在1350-1400℃保温4h烧烧结后,其外表分离层平均孔径为0.18-0.25μm,表现高的纯水渗透通量和抗弯强度,分别为2.27-4.30m3/(m-h-bar)和154.5-216.4 MPa,远高于管式陶瓷膜。本工作以90%-100%NMP溶液为芯液或以乙醇为外凝固浴制备的具有外分离层结构和高度非对称的YSZ中空纤维陶瓷膜特别适用于微滤分离过程及用作超滤或纳滤膜支撑体等。2.低成本堇青石中空纤维陶瓷微滤膜的制备研究堇青石陶瓷的低膨胀和优异抗热震性能使其可用于抗热冲击场合应用。堇青石原料主要以廉价而丰富的粘土等矿物原料合成,已实现大规模工业化生产,因而价格低廉。本实验室曾以堇青石为原料,成功开发出性能良好的多通道管式堇青石陶瓷膜微滤膜。由于堇青石原料价格和膜烧结温度都低于Al2O3和YSZ陶瓷膜,使得同类膜的整体制造成本显著降低,但其仍由传统工艺制备,过程复杂,周期长,需经多次高温烧成。为进一步降低堇青石膜制造成本和提高其渗透性能,本工作以工业级堇青石微粉为原料,通过溶液相转化法制备了非对称梯度多孔堇青石中空纤维陶瓷膜。研究表明,堇青石粉体粒径分布对相转化成膜过程动力学及膜微观结构有重要影响,粒径增大将阻碍指孔结构的形成。以d50为7.8μm的堇青石粉体为原料时,分相过程未发生明显的粘性指进现象,制备的堇青石中空纤维膜主要由内部不规则大孔层结构和外部海绵状细孔层结构构成。本工作重点研究了烧结温度对堇青石中空纤维陶瓷膜微观结构、孔隙率和孔径分布、纯净水和氮气渗透性、弯曲强度及热膨胀性能等的影响。实验结果表明,合适的烧结温度是制备高性能陶瓷膜的重要条件。在1360℃保温2h烧结制备的堇青石中空纤维微滤膜,其分离层最可几孔径约0.38μm,表现出高的纯水和氮气渗透性能,分别达到6.14m3·m-2·h-1·bar-1和782.4 m3·m-2·h-1·bar-1(透膜压差为1bar),远大于孔径相近的管式陶瓷微滤膜；弯曲强度和线性热膨胀系数分别为76.5MPa和2.39×10-6℃-1。本工作表明,通过溶液相转化法,可采用平均粒径大的工业级堇青石粉体为原料通过一步成型制备非对称的多孔堇青石中空纤维陶瓷微滤膜,从而显著降低陶瓷膜的制造成本,制备的堇青石中空纤维膜完全可用于高温废气处理和水处理。3.高渗透性低成本莫来石中空纤维陶瓷膜的制备研究莫来石陶瓷具有高温抗蠕变、高温强度和断裂韧性高、低热膨胀系数和耐腐蚀等性能,常用于高温抗热震多孔陶瓷(陶瓷膜)的制备。莫来石原料一般采用高温(≥1900℃)电熔法或软化学法合成,产量低和成本高。因此,采用先合成莫来石粉体,再进行陶瓷膜制备的工艺路线将不利于降低膜的制造成本。近年来,以天然矿物为主要原料的低成本新型陶瓷膜的制备与应用研究日益受到关注。采用粘土等矿物为主要原料通过原位反应烧结制备多孔莫来石陶瓷,不但可降低制造成本,还可形成针状晶体,有利于提高莫来石陶瓷的机械强度和抗热震性能。本工作基于工业领域对低成本、高性能和功能多样化陶瓷膜的应用需求,以廉价的天然矿物高岭土和Al(OH)3为主要原料,AlF3和V2O5为添加剂,通过相转化法和原位固相反应烧结相结合制备不同微观结构的高渗透性非对称莫来石中空纤维陶瓷膜,并探讨了特殊的针状莫来石结构的形成机理与过程。研究表明,在坩埚密闭条件下于1400℃保温2.5h烧结,可获得接近纯的莫来石相,莫来石中空纤维膜为两层非对称结构,外层为薄的柱状莫来石多孔层,而厚的内层则由均匀分布的针状莫来石晶体交错织构而成,呈现高度多孔性结构,针状莫来石晶体长径比可达到25以上；未密闭烧结时,除形成莫来石主晶相外,还存少量的刚玉相,形成的莫来石晶体为不规则形状,未有针状莫来石晶体形成,制备的莫来石中空纤维膜为梯度多孔结构。EDS组成分析表明制备的针状莫来石表现出明显的化学组成非均匀分布现象,针状莫来石边缘部分富Al(Al/Si=3.47),中心部分富硅(Al/Si=2.38),对应的Al2O3含量范围为66wt%-74wt%。交错连结的高长径比针状莫来石晶体的形成,可显著提高陶瓷膜孔隙率和渗透性。1400℃保温2.5h烧结时,密闭和末密闭条件于制备的针状莫来石中空纤维陶瓷膜的孔隙率分别可达到68.4%和53.6%,氮气渗透通量分别可达到1.82×104m3·m-2·h-1和1.75×103m3·m-2·h-1(操作压力为1.0bar),远高于常用的管式陶瓷膜。研究表明,密闭条件下制备的莫来石中空纤维膜非常适用于高温烟尘废气的处理和用作膜接触反应器等,而未密闭条件下制备的莫来石膜可用于大规模的水处理应用和用作复合陶瓷膜支撑体等。4.中温中空纤维CMFC的制备研究中空纤维(微管)CMFC同时具有管式和板式电池的优点,强度高,启动和稳定时间快,单位体积有效电极面积大,体积电流密度高,热稳定性好,易于实现高温密封和连接等,代表了固体氧化物燃料电池(SOFC)的一种新的发展方向。为实现阳极支撑的微管陶瓷膜燃料电池(CMFC)的产业化应用,开发高性能微管阳极制造技术和探寻化学稳定性好及中温下具有良好的电化学性能的阴极材料是极其重要的工作。文献报道的微管阳极通常采用传统的塑性坯料挤压成型工艺制备,所获得的阳极管一般为对称结构,管壁厚,阳极阻力大。本工作将相转化法应用于NiO/YSZ中空纤维阳极的制备,并在采用真空辅助的浸渍涂覆技术制备致密的YSZ电解质薄膜(10μm)的基础上,分别发展了基于氧化还原稳定的LSCM和具有良好化学稳定性的PNSM为阴极的微管CMFC,其中前者单电池在850℃、800℃和750℃时的最高功率密度分别可达到513 mW/cm2、408 mW/cm2和278 mW/cm2,后者单电池在800℃、700℃和600℃时的最高功率密度分别为459 mW/cm2、325 mW/cm2和172 mW/cm2。考虑到本工作制备的微管电池外径≤1.30 mm,成堆后电池将具有极高的电极面积/体积比值和高的功率输出,因此,以LSCM和PNSM基阴极制备的微管CMFC中温性能已接近实用化水平,可用于高功率输出的小型电池堆制造,用作小型可移动电源,如汽车辅助电源、无线通讯设备电源等。更多还原

【Abstract】 Ceramic membranes are known to be superior to polymeric counterparts due to some special advantages, such as better thermal, chemical and mechanical resistances, narrow pore size distribution, controllable microstructure, long service life and little pollution to the environment, and could be used in very harsh environments. Actually, increasing attention has been paid to ceramic membranes in the past twenty years, and ceramic membranes are nowadays widely used in various fields, including petrochemical industry, chemical industry, metallurgical industry, food industry, environmental engineering, new energy resources and etc. Therefore, ceramic membranes and related separation technologies could play an important role in promoting energy saving, emission reduction and green production, and are very propitious to sustainable development of social economy. However, there are still many obstacles for the further development of traditional planar and tubular ceramic membranes, such as following:(1) low packing density, small active area/volume ratio and thus low separation efficiency; (2) long manufacturing time and complex process, leading to high cost; (3) single product and function. The existing porous ceramic membranes for separation are mainly made of Al2O3 material, and could not meet the requirements for some special applications. Ceramic hollow fiber membranes have recently attracted considerable attention, due to the high active area/volume ratio provided by its high packing density and less material consumption. With the application of ceramic membranes in hollow fiber configuration, the separation equipments can be miniaturized and simplified. Ceramic hollow fiber membranes are commonly fabricated by the phase inversion method in one step, and exhibit self-supported asymmetric structure and high permeability. The application of phase inversion method simplifies the fabrication process of ceramic membranes and could greatly reduce the production cost. Therefore, the development of hollow fiber ceramic membranes has the potential to eliminate the bottleneck problems, which has hindered the development of ceramic membrane technology for a long time.In order to advance the industrial applications of ceramic hollow fiber membranes, the research on the preparative technology of yttria-stabilized zirconia (YSZ) hollow fiber membranes by phase inversion was conducted in our work, and characterization technologies for the prepared membranes have also been developed (Chapter two). The cost-effective cordierite hollow fiber membrane with graded porous structure was fabricated successfully by phase inversion method and using coarse industrial cordierite powder as raw material (Chapter three). The low-cost mullite hollow fiber membrane with high porosity and high permeability was also developed by the combination of phase inversion method and in-situ reaction sintering technique (Chapter four) so as to obtain preferred microstructures for special applications. In the end, we have developed the micro-tubular ceramic membrane fuel cell (CMFC) with redox stable (La0.75Sr0.25)Cr0.5Mn0.5O3 (LSCM) and chemical stable (Pr0.5Nd0.5)0.7Sr0.3MnO3-δ(PNSM) as cathode, respectively, and the phase inversion technique was applied to fabricate the NiO-YSZ hollow fiber anode (Chapter five). The main achievements and innovations in this dissertation are summarized as follows:1. Research on the preparative technology of asymmetric YSZ hollow fiber membranesYSZ is one of the widely used materials for ceramic membranes because of its high mechanical strength, favorable chemical stability and competitive price, and can be used in liquid filtration with much better alkali durability than other ceramic membranes, e.g. Al2O3 membrane. However, pure YSZ composite membrane is rare at the market. This is mainly because of very high sintering temperature (≥1600℃) of YSZ membrane supports made of YSZ powders with an average particle size more than 10μm, and consequent high fabrication cost.Asymmetric YSZ hollow fiber membranes were prepared by the phase inversion method in one step in this work, based on the dry/wet spinning process. The influences of process parameters, including solid content of suspension, composition of internal and external coagulants, on the microstructure and properties of YSZ hollow fiber membranes were investigated systematically in order to effectively control the microstructure and properties for various applications. Results show that all these process parameters have significant influence on the kinetics conditions of phase inversion and thus the microstructure of the YSZ hollow fiber membranes.The increase of YSZ content in suspensions would increment the viscosity, and inhibits the phase inversion behavior. The prepared YSZ hollow fiber membrane shows a typical sandwich structure, i.e. sponge-like structure layer in the middle, and finger-like structure layer at the inner and outer regions, when the suspension has a solid content of 50 wt% and using water as the internal and external coagulants. As the solid content is increased up to 60%-65%, the membranes are composed of thick sponge-like structure at the outer side and finger-like structure at the inner side. Also, the increase of solid content obviously enhances the density of the sponge-like structure layer, and consequently results in higher bending strength but lower pure water permeability.The coagulation power of coagulant can be characterized by the difference of solubility parameters between coagulant and polymer. Larger difference means stronger coagulation power of coagulant. Strong coagulant would lead to rapid precipitation to form finger-like structure and dense skin layer. The addition of solvent NMP into the internal coagulant decreases its coagulation power and thus the precipitation rate in the inner region. This would lead to porous inner surface and facilitate the finger-like pores originated from the outer side to extend to the inner side. Moreover, higher content of NMP in internal coagulant contributes to higher porosity of the membrane and larger pore size of the outer skin layer, which accordingly increases the pure water permeability of the YSZ hollow fiber membrane. When the internal coagulant contains more than 90% NMP, a highly asymmetric structure can be obtained with large finger-like pores extending to the inner surface and the formation of highly porous inner surface. This special microstructure is beneficial for reducing the fluid resistance and increasing the permeability of porous hollow fiber ceramic membranes. The YSZ hollow fiber membrane shows an average pore size of 0.58μm when prepared with pure NMP as internal coagulant and sintered at 1320℃for 5h. The corresponding pure water flux could reach up to 16.34 m3/(m2·h·bar), which is about 2.91 times higher than that prepared using water as internal coagulant. The increase in porosity and the formation of large finger-like pores at higher NMP content would reduce the bending strength of the membranes.Highly permeable porous yttria-stabilized zirconia (YSZ) hollow fiber membranes can be successfully prepared as ethanol instead of water was used as the external coagulant. The prepared YSZ hollow fiber membranes show a special asymmetric structure with an outer-skinned separation layer, highly porous inner surface and sub-layer composed of long and large finger-like pores, and the inner surface shows higher porosity and larger mean pore size. The microstructure has significant effect on the fluid resistance and permeability of the prepared membranes. The YSZ hollow fiber membrane prepared with ethanol as the external coagulant shows much lower fluid resistance, compared with the one using water as the external coagulant. Results show that YSZ hollow fiber membranes with high permeability and high bending strength can be obtained using ethanol as the external coagulant and by controlling the sintering temperature. The outer-skinned YSZ hollow fiber membranes show a pure water flux of 2.27 to 4.30 m3·m-2·h-1·bar-1 and a bending strength of 154.5 to 201.7 MPa when sintered between 1350 and 1400℃, both of which are much higher than the tubular membrane.The present work shows that porous YSZ hollow fiber membranes with highly asymmetric microstructure and outer active layer could be obtained with 90-100vol% NMP as internal coagulant or ethanol as external coagulant. The prepared membranes are suitable to be used for microfiltration and as supports for composite membranes.2. Elaboration of asymmetric porous cordierite hollow fiber membrane for microfiltrationCordierite is one of the most popular ceramic materials for its interesting properties such as good thermal and chemical durability, low thermal expansion coefficient. This makes it particularly suitable to be applied at high temperature where a good thermal shock resistance is required.In our previous work, tubular cordierite membranes have been developed. The cordierite membranes were confirmed to be cost-effective since the material cost and the sintering temperature of cordierite ceramics are much lower than those of A12O3 and YSZ. However, to the best of our knowledge, little work has been done to develop cordierite hollow fiber membrane for microfiltration.Asymmetrical porous cordierite hollow fiber membranes have been successfully prepared by a combined phase inversion and sintering method, using industrial grade cordierite powders as raw material. The particle size of cordierite powders has significant influence on the microstructure of the hollow fiber membranes. Cordierite hollow fiber membranes with the inner macro-void structure and the outer thin sponge-like structure can be obtained when cordierite powder with larger particle size (d50=7.8μm) was used. This special structure is ideal for the actual application of cordierite hollow fiber membranes. But the hollow fiber derived from cordierite powder with smaller particle size (d50=1.6μm) shows large finger-like structure. The sintering temperature has significant effect on the microstructure, porosity and pore size distribution, gas permeability, bending strength and thermal expansion of the hollow fiber membranes prepared with cordierite powder of d50=7.8μm. The porous cordierite hollow fiber membrane shows a nitrogen flux of 745 m3/(m2-h-bar), bending strength of 76.5 MPa, and LTEC of 2.39×10-6℃-1 sintered at 1360℃for 2h, and the probable pore size of its outer separation layer is about 0.38μm. This work demonstrates that the graded porous ceramic hollow fiber membrane for micro-filtration can be prepared using industrial grade cordierite powder with large particle size. The prepared cordierite hollow fiber membrane will be particularly ideal for the treatment of hot waste gas at high temperatures and the treatment of waste water, etc.3. Research on the formation of highly permeable mullite hollow fiber membraneMullite is an important material for thermal shock resistant porous ceramic at elevated temperatures, because of its favorable properties, such as high creep resistance, high strength and fracture toughness at high temperature, low thermal expansion and excellent corrosion resistance. In particular, the formation of acicular mullite grains could increase the porosity, mechanical strength and thermal shock resistance of porous mullite ceramic. Therefore, in this work, highly permeable asymmetric mullite hollow fiber membranes with different microstructure were prepared by the combination of phase inversion and in-situ reaction sintering technique. The natural mineral kaolin and Al(OH)3 were used as the main raw materials, and AIF3 and V2O5 as additives. The mechanism and reaction process for the formation of the special acicular mullite structure were investigated in detail. The hollow fiber membranes sintered at 1400℃for 2.5h in closed crucible shows a nearly pure mullite phase, and consists of two different layers:the outer thin layer composed of prismatic mullite grains, and the inner thick and highly porous layer composed of inter-connected acicular mullite grains with aspect ratio more than 25. For the membrane sintered at the same temperature without closed crucible, the main crystalline phase is mullite accompanied by a small quantity of corundum. The synthesized mullite is in irregular form and no acicular crystal was observed. In this case, the prepared mullite hollow fiber membrane shows a three-layered graded porous structure with decreasing pore size towards the outer side, which is resulted from different precipitation rate. EDS analysis show that large acicular mullite grains exhibit a non-uniform composition across the grain with Si-rich core(Al/Si=2.38) and Al-rich rims (Al/Si=3.47), which corresponds to 66-74 wt% Al2O3.The formation of inter-connected acicular mullite with high aspect ratio could significantly increase the porosity and gas permeability of the hollow fiber membrane. The membranes sintered at 1400℃for 2.5h with and without closed crucible exhibit a high porosity of 68.4% and 53.6%, and high nitrogen flux 1.82×104 m3·m-2·h-1 and 1.75×103 m3·m-2·h-1, respectively, which are much higher than those for commonly- used tubular ceramic membranes. Results show that the acicular mullite hollow fiber membrane sintered in closed crucible is ideal to be applied in the treatment of dust-containing waste gas at elevated temperature and used as membrane contactor for chemical reactions, etc., and that the mullite membrane sintered without crucible can be used for the treatment of waste water and gas in large scale and as support for composite hollow fiber membranes. The preparation method developed in this work could reduce the manufacturing cost of ceramic membrane drastically, and facilitate the formation of mullite hollow fiber membranes with different microstructure to meet requirements for various applications.4. Research on the hollow fiber CMFCHollow fiber (micro-tubular) CMFC possesses many desirable advantages over conventional planar and tubular systems, including high mechanical strength, high electrode area per unit volume and high volume current density, a superior tolerance for thermal stress, more facile sealing, high feasibility for rapid start-up and shut-down operations, as well as rapid response to load variation, and becomes a new development tendency of SOFC. The micro-tubular anodes were often prepared by a traditional plastic extrusion process. The anode derived from this method usually has symmetric structure with large wall thickness which results in a large resistance in the anode side during cell operations.In this research, the phase inversion method was applied to prepare the NiO/YSZ hollow fiber anode, and thin YSZ electrolyte membrane (10μm) was then deposited on the pre-sintered anode by a vacuum-assisted dip-coating technique. Based on this, we developed the micro-tubular CMFCs based on the redox stabe LSCM cathode and chemical stable PNSM cathode, respectively. The former shows peak power densities of 513,408 and 278 mW/cm2 at 850,800 and 750℃, respectively, while the latter exhibits peak power densities of 459,325 and 172 mW/cm2 at 800,700 and 600℃, respectively. In view of the small diameter of the prepared single cells (≤1.30 mm), the resultant hollow fiber CMFC stacks would have high electrode/volume ratio and thus high power output, and could meet the practical requirements of IT-CMFC based on YSZ electrolyte. The anode-supported hollow fiber CMFC is an excellent candidate for smaller scale applications such as auxiliary power units for automobile and power sources for portable wireless devices, etc.更多还原