State Key Laboratory of Material Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan430074, P. R. China.
ACS Appl Mater Interfaces. 2022 Dec 14;14(49):54803-54811. doi: 10.1021/acsami.2c17801. Epub 2022 Dec 2.
Bismuth telluride-based (BiTe) alloys have long been considered the best thermoelectric (TE) materials at room temperature. However, the n-type BiTe alloys always exhibit poor thermoelectric performance than their p-type counterpart, which severely limits the energy conversion efficiency of thermoelectric devices. Here, we demonstrate that incorporating AgBiSe can concurrently regulate the electrical and thermal transport properties as well as improve the mechanical performance of n-type BiTeSeCl for high thermoelectric performance. Among these, AgBiSe effectively enhanced the Seebeck coefficients of n-type BiTeSeCl due to the reduced carrier concentration and reduced the thermal conductivity of n-type BiTeSeCl owing to the enhanced phonon scattering by AgBiSe as well as its low thermal conductivity nature. Consequently, the simultaneous optimization of electrical and thermal transport properties enables us to achieve a maximum of ∼1.21 (at ∼353 K) and an average of ∼1.07 (300-433 K) for 3.5 wt % AgBiSe-incorporated BiTeSeCl, which are ∼25.62 and ∼23.36% larger than those of BiTeSeCl, respectively. This work proves that the incorporation of AgBiSe is an efficient way to improve the thermoelectric performance of bismuth telluride-based materials.
碲化铋基（BiTe）合金长期以来一直被认为是室温下最好的热电（TE）材料。然而，n 型 BiTe 合金的热电性能总是比它们的 p 型对应物差，这严重限制了热电器件的能量转换效率。在这里，我们证明了掺入 AgBiSe 可以同时调节 n 型 BiTeSeCl 的电学和热输运性能，并提高其机械性能，以获得优异的热电性能。其中，AgBiSe 通过降低载流子浓度有效提高了 n 型 BiTeSeCl 的 Seebeck 系数，并通过增强 AgBiSe 的声子散射及其低热导率特性降低了 n 型 BiTeSeCl 的热导率，从而同时优化了电学和热输运性能。因此，掺入 3.5wt%AgBiSe 的 n 型 BiTeSeCl 的最大 约为 1.21（在约 353 K 时），平均 约为 1.07（在 300-433 K 时），分别比 BiTeSeCl 提高了约 25.62%和 23.36%。这项工作证明了掺入 AgBiSe 是提高碲化铋基材料热电性能的有效方法。
