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热电材料是一种能将热能和电能直接转换的材料。本文综述了Ca3CO4O9系氧化物热电材料的晶体结构和研究现状,发现其具有进一步研究的价值。本文还对其研究方向进行了展望。 相似文献
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Ca3Co4O9陶瓷的制备和热电性能 总被引:12,自引:2,他引:12
氧化物半导体陶瓷材料是新型的中、高温热电材料。采用传统固相合成法和溶胶-凝胶法成功地制备了Ca3Co4O9陶瓷。对它们的显微结构和热电性能(Seebeck系数、电导率和热导率)进行了研究。实验结果表明,由两种方法制备得到的Ca3Co4O9陶瓷具有类似的热电性能。Ca3Co4O9陶瓷为取向无规则片状结构,属于p型半导体热电材料,其热电品质因子随温度升高而增大。Ca3Co4O9陶瓷具有大的Seebeck系数和低的热导率,但它的电导率仍然偏低,导致了它的热电品质因子比传统热电合金的热电品质因子低。 相似文献
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采用溶胶-凝胶化学法合成了Ca3Co4O9热电氧化物粉末,分别采用陶瓷烧结工艺方法和放电等离子烧结(Spark Plasma Sintering,SPS)的方法制备了Ca3Co4O9热电氧化物块体材料.利用X射线衍射XRD、扫描电子显微镜SEM和电输运参数测试仪分析了所得样品的物相、微观组织结构、晶粒取向度和电输运性能.结果表明,不同制备方法均可得到纯相的Ca3Co4O9热电氧化物块体材料;通过陶瓷烧结工艺方法制备的Ca3Co4O9热电氧化物块体晶粒取向度较低,但随着成型压力的增加而提高;SPS烧结的方法制备的Ca3Co4O9热电氧化物块体晶粒取向度最高;试样电性能随着晶粒取向度的提高逐渐提高,其中SPS烧结方法制备的块体材料电性能最高,在测试温度最高点700℃时功率因子达3.85 μWmK-2,远高于普通烧结试样. 相似文献
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氧化物热电材料是半导体热电材料中的一种,具有独特的优点和广阔的应用前景。本文介绍了与其研究相关的基础理论以及NaCo2O4热电材料的基本结构和制备方法;对NaCo2O4热电材料Na位和Co位的掺杂的研究现状进行了评述,并对未来发展前景进行了展望。 相似文献
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《现代技术陶瓷》2012,(2):71
主办单位:中国硅酸盐学会特种陶瓷分会清华大学新型陶瓷与精细工艺国家重点实验室协办单位:南京工业大学中国硅酸盐学会特种陶瓷分会定于2012年9月在南京市举办第十七届全国高技术陶瓷学术年会。会议组织委员会热忱欢迎国内从事先进陶瓷研究与开发工作的专家、学者、工程技术人员、学生踊跃参加本次会议。一.会议内容1.学术专题:1)信息功能陶瓷材料(压电、铁电与介电、微波、光电陶瓷材料,薄膜与厚膜制备技术与科学,敏感及传感材料,陶瓷微粉制备与表面处理);2)结构陶瓷材料(超高温、非氧化物、氧化物陶瓷材料,陶瓷基复合材料,耐磨、高温涂层材料,玻璃与非晶态材料,陶瓷微粉制备与表面处理);3)能源材料(固体电解质,固体氧化物燃料电池,光伏电池相关陶瓷材料,储氢材料); 相似文献
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以微米或纳米氧化锆粉体为主原料,钒锆蓝色料或Co3O4为着色剂,添加适量烧结助剂制备蓝色氧化锆陶瓷。研究了氧化锆、助剂、着色剂等对蓝色氧化锆陶瓷颜色及性能的影响。结果表明:用纳米级ZrO2粉体为原料,钒锆蓝色料为着色剂,添加少量烧结助剂,可制得性能优良、颜色亮丽的蓝色氧化锆陶瓷;用纳米级ZrO2为原料,Co3O4为着色剂,添加少量烧结助剂,可制得性能优良、颜色亮丽的钴蓝色氧化锆陶瓷。 相似文献
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本实验采用溶胶-凝胶法制备了Ca3Co4O9陶瓷,寻求了其合适的制备工艺,并对陶瓷的显微结构、物相组成、元素组成等进行了表征测试.实验结果表明:煅烧温度为800~900 ℃时均能得到纯相Ca3Co4O9;Ca3Co4O9为取向无规则层片状组织,颗粒尺寸均匀,为2 μm左右;样品的致密度不高,气孔率相对较大. 相似文献
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Sophie Bresch Björn Mieller Daniela Schönauer-Kamin Ralf Moos Timmy Reimann Fabien Giovannelli Torsten Rabe 《Journal of the American Ceramic Society》2021,104(2):917-927
Calcium cobaltite Ca3Co4O9, abbreviated Co349, is a promising thermoelectric material for high-temperature applications in air. Its anisotropic properties can be assigned to polycrystalline parts by texturing. Tape casting and pressure-assisted sintering (PAS) are a possible future way for a cost-effective mass-production of thermoelectric generators. This study examines the influence of pressure and dwell time during PAS at 900°C of tape-cast Co349 on texture and thermoelectric properties. Tape casting aligns lentoid Co349. PAS results in a textured Co349 microstructure with the thermoelectrically favorable ab-direction perpendicular to the pressing direction. By pressure variation during sintering, the microstructure of Co349 can be tailored either toward a maximum figure of merit as required for energy harvesting or toward a maximum power factor as required for energy harvesting. Moderate pressure of 2.5 MPa results in 25% porosity and a textured microstructure with a figure of merit of 0.13 at 700°C, two times higher than the dry-pressed, pressureless-sintered reference. A pressure of 7.5 MPa leads to 94% density and a high power factor of 326 µW/mK2 at 800°C, which is 11 times higher than the dry-pressed reference (30 MPa) from the same powder. 相似文献
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Qiang Liu Sha Su Zewang Hu Xiaopu Chen Tengfei Xie Zhaoxiang Yang Hongming Pan Xin Liu Jiang Li 《Journal of the American Ceramic Society》2019,102(6):3097-3102
The 0.05 at.% Co:MgAl2O4 precursor was synthesized by the coprecipitation method from a mixed solution of magnesium, aluminum, and cobalt nitrates using ammonium carbonate as the precipitant. 0.05 at.% Co:MgAl2O4 transparent ceramics were successfully obtained via vacuum sintering and hot isostatic pressing (HIP) of 0.05 at.% Co:MgAl2O4 nanopowder calcined at 1100°C for 4 hours. The properties of powder and ceramics were comprehensively investigated. X-ray diffraction (XRD) results showed that Co:MgAl2O4 nanopowder had a pure spinel phase. Also, the in-line transmittances of the HIP posttreated Co:MgAl2O4 ceramics with the thickness of 1.2 mm were 82% at 400 nm and 84.7% at 900 nm. The average grain sizes of 0.05 at.% Co:MgAl2O4 ceramics before and after the HIP posttreatment were 11 and 28 μm, respectively. The calculated ground state absorption cross section of 0.05 at.% Co:MgAl2O4 ceramics was 2.9 × 10−19 cm2, indicating that this ceramics is a promising material applied as a saturable absorber for passive laser Q-switches in the 1.3-1.7 μm domain. 相似文献
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Co2O3的理化性能对ZnO压敏陶瓷电性能的影响 总被引:1,自引:0,他引:1
本文详细研究了氧化钴的理化性能对ZnO压敏陶瓷性能的影响。论述了Co2O3的热特性对压敏陶瓷烧成工艺产生的影响及控制措施,从理论上探讨了氧化 中所含杂质Fe、Cu,Na等对ZnO压敏陶瓷电性能的不利作用。提出了控制的上限,并试制出一种用于氧化锌压敏陶瓷的性能优良的Co2O3粉体。 相似文献
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Chul-Hoon Pai Yasuhiro Sasaki Kunihito Koumoto Hiroaki Yanagida 《Journal of the American Ceramic Society》1991,74(11):2922-2924
Porous SiC ceramics fabricated from hollow particles and polycarbosilane (PSC) are promising materials for high-temperature thermoelectric energy conversion. Reaction sintering of PCS-impregnated compacts of SiC hollow particles gave rise to porous microstructures with the hollow shape remaining. The repetition of the PCS-impregnation and sintering process resulted in only a slight increase in density but in a great improvement in thermoelectric properties. 相似文献
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Shuichi Funahashi Hanzheng Guo Jing Guo Amanda L. Baker Ke Wang Kosuke Shiratsuyu Clive A. Randall 《Journal of the American Ceramic Society》2017,100(8):3488-3496
Cold‐sintered ZnO and Ca3Co4O9 polycrystalline materials were shown to have thermoelectric properties comparable to those of conventionally sintered ceramics. Extending these processing conditions into a cold sintering co‐fired ceramic (CSCC) technology, we integrated n‐type and p‐type thermoelectric oxides and a separating insulating layer to demonstrate functional multilayer thermoelectric generator devices. A co‐fired structure with an insulating 8 mol% yttria‐stabilized zirconia (8YSZ) layer enabled multilayer thermoelectric generators (TEG) to be fabricated with a 5 n‐p junction device (20 layers). A transmission electron microscopy analysis of the interfaces between the various materials under the co‐firing cold sintering showed some interdiffusion of chemical constitutes in a 2.0 μm interface region between the respective ceramic phases. The co‐firing of multilayer ceramic and polymer structures were also shown to be possible using insulation layers of polytetrafluoroethylene (PTFE) thermoplastic layers. This demonstrated the feasibility of a single‐step process for new structures with both ceramics and polymers, opening up new directions for many new device designs. 相似文献