Flexible Bi_0.5Sb_1.5Te₃-based thermoelectric thin films are promising p-type candidates for applications in flexible and wearable electronics. Here, we use thermal evaporation deposition and subsequent post-annealing treatment to prepare Bi_0.5Sb_1.5Te₃ crystal-amorphous hybrid thin films. Tuning the annealing temperature can achieve an optimized hybrid level between amorphous and crystalline Bi_0.5Sb_1.5Te₃, leading to an optimized figure of merit as high as ∼1.5 at room temperature, which is an ultrahigh value in the p-type Bi_0.5Sb_1.5Te₃ thin films. Our single parabolic band model and Density-Functional Theory calculation results indicate that such a high value should be attributed to the high effective mass induced by the proper crystal-amorphous hybrid structure. Our study indicates that a crystal-amorphous compositing can be used as a new methodology to achieve ultrahigh performance in thermoelectric materials.

基于柔性Bi _0.5 Sb _1.5 Te ₃的热电薄膜是有希望用于柔性和可穿戴电子产品的p型候选材料。在这里，我们使用热蒸发沉积和随后的后退火处理来制备Bi _0.5 Sb _1.5 Te ₃晶体-非晶杂化薄膜。调节退火温度可以实现非晶和结晶Bi _0.5 Sb _1.5 Te ₃之间的最佳混合水平，从而导致在室温下的最佳品质因数高达〜1.5，这是p型Bi _0.5 Sb的超高值_1.5 Te ₃薄膜。我们的单抛物线能带模型和密度泛函理论计算结果表明，如此高的值应归因于适当的晶体-非晶杂化结构引起的高有效质量。我们的研究表明，晶体-非晶复合材料可以用作在热电材料中实现超高性能的新方法。