Boosting electrical properties of flexible PEDOT/cellulose fiber composites through the enhanced interface connection with novel combined small-sized anions

Rapid development of flexible electronics has raised the demand for renewable conductive materials. Biomass-derived cellulose fibers (CFs) are very promising candidates due to their outstanding advantages. In this paper, flexible, lightweight and freestanding biomaterial with high electrical conductivity was prepared via in situ chemical polymerization process using 3,4-ethylenedioxythiophene (EDOT) and CFs. In order to improve the performance of PEDOT/CFs, novel combined small-sized anion doping agents, sulphosalicylic acid (SSA) and sodium benzenesulfonate (SBS), were adopted to construct a well-organized conducting layer. The obtained PEDOT layer possessed good crystallinity and high doping level and was uniformly coated onto the surface of CFs through the dopant-dependent interface. The PEDOT:SSA-SBS/CFs exhibited electrical conductivity as high as 472 S/m and the mass loading was up to 1.92 mg/cm(2). Moreover, the flexible biomaterial displayed favorable electrochemical stability. Hence, the results presented here provide a new way to produce highly conducting and flexible biomaterial. Graphic abstract