空位填充型Heusler合金的室温热电性能研究与开发

近年来新兴科技领域的快速发展对室温区高性能热电材料的开发提出了迫切需求，比如芯片制冷等。但是目前适用的热电材料体系非常有限，而且现有室温区热电材料还都存在机械性能差的缺点，不利于热电器件的加工。half-Heusler合金机械性能和热稳定性好、室温热电功率因子大，如果能克服晶格热导率高的缺点，将是非常理想的室温热电材料体系。然而，目前国内外对half-Heusler热电材料的研究大多集中在高温区，没有开发室温区热电性能的报道。申请人拟利用所发现的空位填充型Heusler合金具有极低的室温晶格热导率这一特质，以室温具有高功率因子的half-Heusler热电材料为基体，结合理论预测和实验分析，选取合适原子对half-Heusler晶格中天然空缺的4d晶位进行适量填充，制备得到一系列室温热电性能优异和机械性能较好的新型空位填充型Heusler热电材料，推动这类材料作为室温热电材料的研究和开发。

The rapid development of emerging science and technology in recent years has created an urgent need for the development of high-performance thermoelectric materials around room temperature, such as self-powered wearable electronics, chip cooling and so on. However, there are currently very few applicable thermoelectric material systems, and the existing room-temperature thermoelectric materials have the disadvantage of poor mechanical properties, which is bad for the mechanical processing of thermoelectric devices. Half-Heusler alloys exhibit good mechanical properties and thermal stability as well as large room-temperature thermoelectric power factor. If the high lattice thermal conductivity can be effectively reduced, half-Heusler alloys could be ideal room-temperature thermoelectric materials. At present, most of the research on half-Heusler thermoelectric materials is focused on the high-temperature thermoelectric properties, and, to our knowledge, there is no report on the development of room-temperature thermoelectric properties. In this project, the applicant proposes to prepare a series of novel vacancy-filled Heusler alloys with excellent room-temperature thermoelectric properties and good mechanical properties on the basis that the discovered vacancy-filled Heusler alloys have extremely low lattice thermal conductivities at room temperature. In combination of theoretical prediction and experimental results, appropriate atoms will be selected to fill the naturally vacant 4d crystal sites of the half-Heusler matrix with high thermoelectric power factor at room temperature, and thus the room-temperature thermoelectric alloys are synthesized, which will promote the research and development of these vacancy-filled Heusler alloys as room-temperature thermoelectric materials.