MEMS Center, Harbin Institute of Technology, Harbin 150001, China.
Science and Technology on Analog Integrated Circuits Laboratory, Chongqing 400060, China.
ACS Appl Mater Interfaces. 2023 Jul 5;15(26):31812-31823. doi: 10.1021/acsami.3c05344. Epub 2023 Jun 22.
Energy recovery and reuse, industrial waste heat, and thermal energy recovery and conversion in emerging electronic devices are topics of widespread interest. Flexible composite thermoelectric (TE) films have become the key to TE conversion, and many studies and synthesis methods related to them have made great progress. However, little research has been performed on the corresponding composites of typical TE materials with low-dimensional nanotubular materials, particularly modulation of the overall TE properties using doped low-dimensional nanotubular materials. In this work, high-quality bismuth telluride (BiTe) nanowires and boron nitride nanotubes (BNNTs) were prepared using electrolytic deposition and high-temperature catalytic deposition, respectively. BiTe-BNNTs composite films were prepared using a solvent hot pressing method. The BiTe-BNNTs composite film conductivity reached 179.6 S/cm at room temperature (300 K), the corresponding Seebeck coefficient was 171.4 μV/K, and the power factor (PF) was 52.8 nW/mK. Carbon doping of BNNTs resulted in carbon-boron nitride nanotubes (BCNNTs), and BiTe-BNNTs composite films were prepared. The BiTe-BCNNTs composite films obtained a conductivity of 4629.6 S/cm, at room temperature (300 K), a corresponding Seebeck coefficient of 181.2 μV/K, and a PF of 1520.0 nW/mK. This study has important reference value for the application of TE conversion. Moreover, the electrical conductivity decreased by no more than 10% after 400 cycles of bending tests, and the electrical conductivity showed signs of recovery after repressing thermally, which undoubtedly proves that BiTe-BCNNTs composite films have good flexibility and thermal stability, and this has contributed to the application and promotion of flexible thermoelectric materials.
能量回收和再利用、工业余热以及新兴电子设备中的热能回收和转换是广泛关注的话题。柔性复合热电（TE）薄膜已成为 TE 转换的关键，许多与之相关的研究和合成方法已经取得了很大的进展。然而，对于典型 TE 材料与低维纳米管状材料的相应复合材料的研究却很少，特别是使用掺杂的低维纳米管状材料来调制整体 TE 性能。在这项工作中，使用电解沉积和高温催化沉积分别制备了高质量的碲化铋（BiTe）纳米线和氮化硼纳米管（BNNTs）。使用溶剂热压法制备了 BiTe-BNNTs 复合薄膜。室温（300 K）下，BiTe-BNNTs 复合薄膜的电导率达到 179.6 S/cm，相应的 Seebeck 系数为 171.4 μV/K，功率因子（PF）为 52.8 nW/mK。BNNTs 的碳掺杂导致了碳-氮化硼纳米管（BCNNTs）的形成，并制备了 BiTe-BNNTs 复合薄膜。所获得的 BiTe-BCNNTs 复合薄膜在室温（300 K）下的电导率为 4629.6 S/cm，相应的 Seebeck 系数为 181.2 μV/K，功率因子为 1520.0 nW/mK。这项研究对 TE 转换的应用具有重要的参考价值。此外，经过 400 次弯曲测试后，电导率下降不超过 10%，并且在热压后电导率显示出恢复的迹象，这无疑证明了 BiTe-BCNNTs 复合薄膜具有良好的柔韧性和热稳定性，这有助于推动柔性热电材料的应用和推广。
