Thermoelectric generators, capable of directly converting heat into electricity, hold great promise for tackling the ever-increasing energy sustainability issue. The thermoelectric energy conversion efficiency is heavily dependent upon the materials’ performance that is quantified by the dimensionless figure-of-merit (ZT). Therefore, the central issue in the research of thermoelectric materials lies in continuously boosting the ZT value. Although thermoelectric effects were discovered in the nineteenth century, it was only until the 1950s when classic materials like Bi₂Te₃ and PbTe were developed and basic science of thermoelectrics was established. However, the research of thermoelectrics did not take a smooth path but a rather tortuous one with ups and downs. After hiatus in the 1970s and 1980s, relentless efforts starting from the 1990s were devoted to understanding the transport and coupling of electrons and phonons, identifying strategies for improving the thermoelectric performance of existing materials, and discovering new promising compounds. Rewardingly, substantial improvements in materials’ performance have been achieved that broke the ZT limit of unity. Meanwhile, advancements in fundamental understanding related to thermoelectrics have also been made. In this Review, recent advances in the research of thermoelectric materials are overviewed. Herein, strategies for improving and decoupling the individual thermoelectric parameters are first reviewed, together with a discussion on open questions and distinctly different opinions. Recent advancements on a number of good thermoelectric materials are highlighted and several newly discovered promising compounds are discussed. Existing challenges in the research of thermoelectric materials are outlined and an outlook for the future thermoelectrics research is presented. The paper concludes with a discussion of topics in other fields but related to thermoelectricity.

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热电学的进展

能够直接将热量转化为电能的热电发电机有望解决不断增长的能源可持续性问题。热电能量转换效率在很大程度上取决于材料的性能，该性能由无量纲的品质因数（ZT）量化。因此，热电材料研究的中心问题在于不断提高ZT值。尽管在19世纪发现了热电效应，但直到1950年代，经典材料Bi ₂ Te ₃才被发现。开发了PbTe和PbTe，并建立了热电学的基础科学。但是，热电学的研究并没有走一条平坦的路，而是曲折的坎with。在1970年代和1980年代中断之后，从1990年代开始不懈的努力致力于理解电子和声子的传输和耦合，确定改善现有材料热电性能的策略，并发现新的有前途的化合物。奖励性的是，材料性能得到了实质性的改善，从而打破了ZT团结的极限。同时，在与热电学有关的基本理解上也取得了进步。在这篇综述中，概述了热电材料研究的最新进展。这里，首先回顾了用于改善和解耦各个热电参数的策略，以及关于开放性问题和截然不同的观点的讨论。着重介绍了许多优质热电材料的最新进展，并讨论了几种新发现的有前途的化合物。概述了热电材料研究中存在的挑战，并提出了对未来热电研究的展望。本文最后讨论了其他领域中与热电有关的主题。