Liu Ye, Villalva Diego Rosas, Sharma Anirudh, Haque Md Azimul, Baran Derya
Physical Science and Engineering Division, KAUST Solar Center (KSC), King Abdullah University of Science and Technology, Thuwal 23955-6900, Saudi Arabia.
ACS Appl Mater Interfaces. 2021 Jan 13;13(1):411-418. doi: 10.1021/acsami.0c16740. Epub 2020 Dec 29.
Molecular doping is a powerful tool to tune the thermoelectric (TE) properties of solution-processed semiconductors. In this work, we prepared a binary composite and effectively doped both of its constituents, that is, naphthalene diimide-bithiophene copolymers (PNDI2OD-T2) and single-walled carbon nanotubes (SWCNTs), by a 1-benzimidazole derivative (N-DMBI). The doped composites show an n-type character and an in-plane TE figure of merit (), exceeding the values obtained with the doped polymers. The use of SWCNTs consistently results in a higher σ with a maximum value above 10 S/cm, resulting in the highest power factor of 18.1 μW/mK for an SWCNT loading of 45.5 wt %. Furthermore, an SWCNT content up to 9 wt % does not compromise the low thermal conductivity of the polymer matrices, leading to a value of 0.0045. The n-type composites show good solution processability and relatively stable Seebeck coefficients upon air exposure for 8 months.
分子掺杂是调节溶液处理半导体热电（TE）性能的有力工具。在这项工作中，我们制备了一种二元复合材料，并通过1-苯并咪唑衍生物（N-DMBI）有效地对其两种成分进行了掺杂，即萘二亚胺-联噻吩共聚物（PNDI2OD-T2）和单壁碳纳米管（SWCNT）。掺杂后的复合材料呈现n型特性和面内热电优值（），超过了掺杂聚合物所获得的值。使用SWCNT始终会导致更高的电导率σ，最大值超过10 S/cm，对于45.5 wt%的SWCNT负载量，功率因数最高可达18.1 μW/mK。此外，高达9 wt%的SWCNT含量不会损害聚合物基体的低热导率，导致值为0.0045。n型复合材料表现出良好的溶液可加工性，并且在空气中暴露8个月后塞贝克系数相对稳定。
