材料基因组框架下碲化铋基纳米结构材料热电性能的实验研究

It is becoming the frontier research and has been attracting intense interest to apply nanotechnology in the development of bismuth telluride-based materials, which is expected to break the low efficiency bottleneck of thermoelectrics. The Materials Genome Initiative with new integrated computational, experimental, and data informatics tools is believed to effectively promote the study and development of high performance thermoelectric materials. The project aims at proposing comprehensive evaluation method for nanoscale thermoelectric materials, systematically studying the thermoelectric properties of bismuth telluride-based nanomaterials, preliminarily building the corresponding database, and exploring the influencing mechanisms of thermoelectric properties in the framework of Materials Genome Initiative. By overcoming the difficulties in comprehensively evaluating nanoscale thermoelectric materials, bismuth telluride-based nanowires and nanofilms with different elements match will be systematically prepared. And the thermoelectric properties will be studied by applying the T type method and femtosecond laser pump-probe method, including thermal conductivity, Seebeck coefficient, and electrical conductivity. Furthermore, the phonon thermal conductivity and electronic thermal conductivity will be extracted based on magnetic coupling. The influencing mechanisms of element match and preparing parameters on the thermoelectric properties will be studied. Finally, new high performance bismuth telluride-based nanomaterials will be developed based on the experimental study.

将纳米技术应用于室温下热电性能最好的碲化铋基材料开发被认为最有望突破热电转换效率瓶颈而成为国际研究的前沿和热点。采用集成的计算、实验和数据平台的“材料基因组计划”将有力的推动该研究进程。本项目旨在材料基因组框架下，形成纳米材料热电性能综合表征方法，系统研究碲化铋基纳米材料的热电性能，初步建立数据库并揭示影响其热电性能的微观物理机制，为开发新型高性能碲化铋基纳米热电材料提供实验依据和理论指导。项目拟攻克纳米样品极易破坏、个体差异大和热电性能难以综合表征等关键难题，系统制备出元素配比严格可控的碲化铋基纳米线和纳米薄膜；分别采用申请人开发的综合T形法和双波长飞秒激光泵浦-探测法测量其热导率、电导率和塞贝克系数；基于强磁场耦合区分电子和声子对材料热导率的不同贡献；揭示元素配比和工艺参数对热电性能影响的规律和物理机制；基于实验测试结果，通过理论计算开发制备高性能碲化铋基纳米热电材料。

将纳米技术应用于室温下热电性能最好的碲化铋基材料开发被认为最有望突破热电转 换效率瓶颈而成为国际研究的前沿和热点。本项目采用水热合成法、磁控溅射法等制备了碲化铋基纳米结构热电材料，采用综合T形法，飞秒激光泵浦-探测瞬态热反射法等研究了碲化铋基微米纤维，纳米线和纳米薄膜的热电性质，采用水热合成法制备了Sb2Se3纳米线并进行了结构表征，采用纳米操作探针实现了单根纳米线的转移和悬架搭接，采用综合T形法测量了其热电性质，研究了其中的物理机制和规律；采用第一性原理计算分析了影响碲化铋基纳米结构材料热电性能的微观物理机制和规律，揭示了样品尺寸及掺杂对其性能的影响机制。探索了对纳米复合材料热电性质调控的机理与手段。共获得国际传热传质中心2018年度Hartnett-Irvine奖，教育部2018年度自然科学一等奖，2019年亚洲热物性研究青年科学家奖，共发表SCI期刊论文24篇，在国际会议作特邀报告7次。