Temperature‐dependent thermal properties of phase‐pure polycrystalline ternary chalcogenides Cu₄Bi₄S₉ and Cu₄Bi₄Se₉ are reported. The structure and bonding in these materials result in very low thermal conductivity values (<0.8 W m⁻¹ K⁻¹ at room temperature) for both materials. The lattice contribution, Debye temperatures, and Sommerfeld coefficient are obtained from low‐temperature heat capacity data that also indicate very small electronic contributions to the heat capacity for these materials. This study aids in the identification of new nontoxic, earth‐abundant resistive ternary chalcogenide materials with low thermal conductivity for potential thermal barrier coating and rewriteable storage applications.

中文翻译：

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三元硫属元素化物Cu4Bi4M9（M = S，Se）的极低导热率的热学性质

据报道，相纯多晶三元硫属元素化物Cu ₄ Bi ₄ S ₉和Cu ₄ Bi ₄ Se _9的温度相关热性能。这些材料的结构和键合导致非常低的热导率值（<0.8 W m ^-1  K ^-1在室温下）。晶格贡献，德拜温度和Sommerfeld系数是从低温热容数据获得的，这些数据也表明这些材料对热容的电子贡献很小。这项研究有助于识别具有低热导率的新型无毒，富含地球的电阻性三元硫族化物材料，用于潜在的热障涂层和可重写存储应用。