Discovering new materials and developing novel synthesis techniques are like two wheels of a cart in materials-based science and technology. As is often the case, innovative synthesis recipe can rejuvenate the research landscape of a material that is otherwise thought to be matured. A good example of such is the narrow band gap semiconductor/semimetal family of A 2 Q (A = Cu, Ag; Q = S, Se, Te). Here we briefly review the recent development of synthesis recipes and the impact on the thermoelectric study of A 2 Q. While the mixed ionic electronic conduction in A 2 Q promises advantages in thermoelectricity, it poses challenges in material synthesis and applications. The concepts, approaches, and strategies embodied in these novel synthesis recipes of A 2 Q can be extended to other materials in diverse regimes of fundamental research and technical applications beyond thermoelectrics.

中文翻译：

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新颖的合成配方促进了A 2 Q的热电研究（A = Cu，Ag； Q = S，Se，Te）

发现新材料并开发新颖的合成技术就像基于材料的科学技术中的两个手推车一样。通常情况下，创新的合成配方可以使原本被认为已经成熟的材料的研究前景焕发活力。一个很好的例子是A 2 Q的窄带隙半导体/半金属族（A = Cu，Ag； Q = S，Se，Te）。在这里，我们简要回顾一下合成配方的最新发展以及对A 2 Q的热电研究的影响。虽然A 2 Q中的混合离子电子传导有望在热电方面取得优势，但它在材料合成和应用方面也带来了挑战。概念，方法，