The Zintl phase Ca₁₄AlBi₁₁ has been synthesized and structurally characterized for the first time. Its crystal structure has been carefully determined by single-crystal X-ray diffraction methods, and shown to crystallize in the tetragonal space group I4₁/acd, No. 142 (Z = 8). Not surprisingly, Ca₁₄AlBi₁₁ adopts the Ca₁₄AlSb₁₁-structure type, although Ca₁₄AlBi₁₁ is the first alumo-bismuthide among the ‘14–1–11’ family whose structure is unequivocally established. In the respective Ca–Al–Bi ternary system, so far, Ca₁₄AlBi₁₁ is only the second identified phase. Electronic structure calculations for this new bismuthide indicate the opening of a small gap at the Fermi level, suggestive of intrinsic semiconducting behavior. Resistivity measurements on as-synthesized single crystalline sample show temperature dependence akin to those of heavily doped semiconductors or the bad metals. In addition to the moderately high electrical conductivity (ρ₃₀₀ = 1.05 mΩ cm), specimens of Ca₁₄AlBi₁₁ also exhibit excellent thermopower, with high-temperature (HT) values of the Seebeck coefficient approaching and possibly exceeding 200 μV/K. These metrics, coupled with preliminary HT conductivity estimates, are comparable with the best state-of-the-art p-type Zintl thermoelectric materials and are among the best within the known bismuthides with the same atomic arrangements. Therefore, Ca₁₄AlBi₁₁ represents a new platform for the development of a novel, low-cost thermoelectric materials family with first-class transport properties and enhanced thermal stability. Initial data suggest that Ca₁₄AlBi₁₁ is amenable to doping, which opens up many opportunities for tuning charge-carrier concentration and optimizing the transport properties in this new, HT thermoelectric material.

Zintl相Ca ₁₄ AlBi ₁₁首次合成并进行了结构表征。其晶体结构已通过单晶X-射线衍射法经过精心确定，并且所示的四方晶空间群结晶我4 ₁ / ACD，第142号（Ž  = 8）。毫不奇怪，Ca ₁₄ AlBi ₁₁采用Ca ₁₄ AlSb ₁₁结构类型，尽管Ca ₁₄ AlBi ₁₁是“ 14-1-11”族中第一个铝-铋族，其结构是明确确立的。到目前为止，在各自的Ca-Al-Bi三元体系中，Ca ₁₄AlBi ₁₁只是确定的第二阶段。这种新的铋的电子结构计算表明，在费米能级上有一个小缝隙的开放，这暗示了固有的半导体行为。合成后的单晶样品的电阻率测量结果显示出温度依赖性，类似于重掺杂半导体或有害金属。除了适度高的电导率（ρ ₃₀₀  = 1.05毫欧厘米），钙的试样₁₄阿尔比₁₁还表现出优异的热电动势，与塞贝克系数接近并可能超过200μV/ K的高温（HT）的值。这些指标加上初步的HT电导率估算值可与最佳的最新技术相媲美在已知的具有相同原子排列的铋中，p型Zintl热电材料是最好的。因此，Ca ₁₄ AlBi ₁₁代表了开发具有一流的传输性能和增强的热稳定性的新型低成本热电材料家族的新平台。初步数据表明，Ca ₁₄ AlBi ₁₁易于掺杂，这为调节载流子浓度和优化这种新型HT热电材料的传输提供了许多机会。