High-Performance MoS<sub>2</sub>/SWCNT Composite Films for a Flexible Thermoelectric Power Generator
Duo Jiang, Yi Li, Zan Li, Zhaohua Yang, Zhixiang Xia, Ping Fu, Yunfei Zhang, Feipeng Du
Abstract
Single-walled carbon nanotube (SWCNT)-based thermoelectric materials have been extensively studied in the field of flexible wearable devices due to their high flexibility and excellent electrical conductivity (σ). However, poor Seebeck coefficient ( S ) and high thermal conductivity limit their thermoelectric application. In this work, free-standing MoS 2 /SWCNT composite films with improved thermoelectric performance were fabricated by doping SWCNTs with MoS 2 nanosheets. The results demonstrated that the energy filtering effect at the MoS 2 /SWCNT interface increased the S of composites. In addition, the σ of composites was also improved due to the reason that S –π interaction between MoS 2 and SWCNTs made good contact between MoS 2 and SWCNTs and improved carrier transport. Finally, the obtained MoS 2 /SWCNT showed a maximum power factor of 131.9 ± 4.5 μW m –1 K –2 at room temperature with a σ of 680 ± 6.7 S cm –1 and an S of 44.0 ± 1.7 μV K –1 at a MoS 2 /SWCNT mass ratio of 15:100. As a demonstration, a thermoelectric device composed of three pairs of p–n junctions was prepared, which exhibited a maximum output power of 0.43 μW at a temperature gradient of 50 K. Therefore, this work offers a simple method of enhancing the thermoelectric properties of SWCNT-based materials.