气－固反应制备IyCo4Sb12/SnO2 纳米复合材料及其热电性能研究

项目名称： 气－固反应制备IyCo4Sb12/SnO2 纳米复合材料及其热电性能研究

项目编号： No.50802109

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 电工技术

项目作者： 陈喜红

作者单位： 中国科学院上海硅酸盐研究所

项目金额： 20万元

中文摘要： 本项目针对填充CoSb3基热电材料，系统研究了异相混合(ex-situ) 与原位生长（in-situ）纳米复合材料的制备方法与微结构控制及其与性能的关系。我们制备的纳米复合热电材料通过引入的纳米颗粒散射中长波声子降低材料的晶格热导率，显示了不同程度(10-30%)晶格热导率降低及由此而引起的材料热电优值提高。我们率先提出利用原位生长纳米相，即利用Ga元素的亚稳填充制备YbyCo4Sb12/GaSb纳米复合材料，由于纳米颗粒所产生的界面势垒能有效过滤低能量载流子，从而增大赛贝克系数，复合材料的热电优值突破1.45，为单填充方钴矿材料的最高值。同时，通过设计调控制备工艺，控制GaSb的尺寸，部分实现了CoSb3基热电材料微结构的可控制备与性能调控。在本项目资助下，在Acta Mater.、Scripta Materialia、Appl. Phys. Lett.等期刊发表填充CoSb3基热电材料相关SCI 论文8篇，申请中国专利和美国专利各2项。2009年，项目负责人获教育部科研启动基金的资助，2010年入选 "上海市青年科技启明星计划"，2011年入选"中国科学院青年创新促进会"会员。

中文关键词： 填充方钴矿；纳米复合材料；热电；声子散射；

英文摘要： This program focuses on developing novel methods for synthesizing bulk nanocomposites and investigating the effect of multi-scale microstructures on thermoelectric performance. Ex-situ synthesis methods, such as sol-gel and vapor-solid, were used to introduce local phonon scattering centers such as nanodispersions, the lattice thermal conductivity of the host material was reduced and then the ZT values was improved. A new synthesis method for filled skutterudite-based nanocomposites was developed. Utilizing the metastable void filling characteristic of Ga in the icosahydron cages of CoSb3, the homogenously dispersed GaSb nanoinclusions was successfully introduced into Yb0.26Co4Sb12. The Seebeck of nanocomposite is obviously enhanced by 15% compared with that of single-phase Yb-filled CoSb3. As a result, ZT value was improved significantly in a wide working temperature range and the highest ZT value 1.45 was achieved at 850 K. Also, the influence of cooling technique on the synthesis of nano composites and the relationship of microstructure and TE performance are studied systematically. Project director was sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (2009), Shanghai Rising-Star Program (2010).

英文关键词： filled skutterudite；nanocomposites；thermoelectric；phonon scattering；