Flexible Thermoelectric Fabrics Based on Layered Topological Insulator Bi$_{2}$Se$_{3}$ Nanoplates/Polyvinylidene Fluoride Composite

We report a highly-flexible and ultrathin thermoelectric fabrics based on topological insulator (TI) Bi$_{2}$Se$_{3}$ Nanoplates/PVDF Composite, which show a room temperature Seebeck coefficient, electrical conductivity, and figure of merit ZT -8 $\mu$V/K, 5000 S/m, 0.02, respectively. This results demonstrate that Bi$_{2}$Se$_{3}$ Nanoplates/PVDF composite exhibit favorable thermoelectric characteristics, which opens a new avenue to fabricate highly-flexible and lightweight sustainable energy sources that could be compatible with portable/wearable electronic devices. The low thermal conductivity of the composites ($\sim$ 0.42 W/(mK)) suggests the nonconducting host polymer matrix PVDF serves to bind the conducting topological insulator (TI) Bi$_{2}$Se$_{3}$ while still maintaining an adequate power factor and figure of merit. The flexible thermoelectric fabrics based on layered topological insulator Bi$_{2}$Se$_{3}$ Nanoplates/PVDF composite that with comparable thermoelectrical efficiency is only a typical example that showing the promising of the present method for further applications of 2D topological insulator like Bi$_{2}$Se$_{3}$, Bi$_{2}$Te$_{3}$ and Sb$_{2}$Te$_{3}$ At their current performance, if enough thermal energy is available, the composites could be used to provide sufficient thermoelectric power for low powered personal and portable electronics.