Thermoelectric materials have long been proven to be effective in converting heat energy into electricity and vice versa. Since semiconductors have been used in the thermoelectric field, much work has been done to improve their efficiency. The interrelation between their thermoelectric physical parameters (Seebeck coefficient, electrical conductivity, and thermal conductivity) required special tailoring in order to get the maximum improvement in their performance. Various approaches have been reported in the research for developing thermoelectric performance, including doping and alloying, nanostructuring, and nanocompositing. Among different types of thermoelectric materials, layered chalcogenide materials are unique materials with distinctive properties. They have low self-thermal conductivity, and their layered structure allows them to be modified easily to improve their thermoelectric performance. In this review, basic knowledge of thermoelectric concepts and challenges for enhancing the figure of merit is provided. It discusses briefly different groups of layered chalcogenide thermoelectric materials with their structure and thermoelectric properties. It also reports different approaches in the literature for improving their performance and the recent progress done in this field. It highlights graphene as a promising nano additive to layered chalcogenide materials’ matrix and shows its effect on enhancing their figure of merit.

中文翻译：

---

层状硫族化物材料的热电性能增强

长期以来，热电材料已被证明可有效地将热能转化为电能，反之亦然。由于半导体已被用于热电领域，因此已经做了很多工作来提高其效率。它们的热电物理参数（塞贝克系数，电导率和热导率）之间的相互关系需要进行特殊调整，以最大程度地提高其性能。在研究中已经报道了各种用于开发热电性能的方法，包括掺杂和合金化，纳米结构和纳米复合。在不同类型的热电材料中，硫族化物层状材料是具有独特性能的独特材料。它们的自导热率低，它们的分层结构使它们易于修改，以改善其热电性能。在这篇综述中，提供了热电概念的基本知识以及提高品质因数的挑战。它简要讨论了不同种类的层状硫族化物热电材料及其结构和热电性能。它还报告了文献中改进其性能的不同方法以及该领域最近的进展。它突出了石墨烯作为层状硫族化物材料基质的有前途的纳米添加剂，并显示了其在提高其品质因数方面的作用。它简要讨论了不同种类的层状硫族化物热电材料及其结构和热电性能。它还报告了文献中改进其性能的不同方法以及该领域最近的进展。它突出了石墨烯作为层状硫族化物材料基质的有前途的纳米添加剂，并显示了其在提高其品质因数方面的作用。它简要讨论了不同种类的层状硫族化物热电材料及其结构和热电性能。它还报告了文献中改进其性能的不同方法以及该领域最近的进展。它突出了石墨烯作为层状硫族化物材料基质的有前途的纳米添加剂，并显示了其在提高其品质因数方面的作用。