热电材料是一类能够实现热能和电能之间直接相互转化的半导体功能材料,在热电制冷和温差发电等领域具有广阔的应用前景。目前,转换效率低是制约热电材料应用的主要原因,因此,如何提高和优化影响转换效率的热电优值是当前研究的主要问题。Cu_2Se基“声子液体”类热电材料是一种利用特殊晶体结构获得极低热导率的新型高性能热电材料,Cu_2Se在高温时会发生结构性相变,Cu原子变成可自由迁移的类液态Cu离子,通过强烈散射声子来降低材料的晶格热导率,对Cu_2Se的研究大大推动了热电领域的发展。本文围绕“声子液体”类热电材料,分析概括了Cu_2Se的性质、晶体结构与应用领域,重点阐述了国内外有关Cu_2Se基“声子液体”类热电材料的研究成果、制备方法以及性能优化手段,结合目前的研究状况分析并展望了今后“声子液体”类热电材料的发展方向以及提高性能的策略。 Thermoelectric materials are a kind of semiconductor functional materials that can realize direct mutual conversion between thermal energy and electric energy and have broad application prospects in the fields of thermoelectric cooling and thermoelectric power generation. At present, the low conversion efficiency is the main reason that restricts the application of thermoelectric materials. Therefore, how to improve and optimize the thermoelectric figure of merit which affects the conversion efficiency is the main problem in current research. Cu_2Se-based phonon liquid thermoelectric material is a new type of high-performance thermoelectric material with very low thermal conductivity with special crystal structure. Cu_2Se undergoes structural phase transition at high temperature and Cu atom becomes free-migrating Of liquid Cu ions, which can reduce the lattice thermal conductivity of the material by strongly scattering phonons. The research on Cu_2Se greatly promoted the development of thermoelectric field. This article focuses on the “phonon liquid” type thermoelectric materials, analyzes and summarizes the properties of Cu_2Se, crystal structure and application areas, focusing on the domestic and international research on Cu_2Se-based “phononic liquid” thermoelectric materials research methods, preparation methods Combined with the current research situation, the development direction of “phononic liquid” thermoelectric materials and the strategy of improving performance are analyzed and prospected in the future.