FlexiblePEDOT:PSS/polyimide aerogels with linearly responsive and stableproperties for piezoresistive sensor applications

XinZhao, Wenlong Wang, Zhe Wang, JiangnanWang, Tao Huang, Jie Dong*,Qinghua Zhang*

ChemicalEngineering Journal, 2020, 395: 125115

https://doi.org/10.1016/j.cej.2020.125115

Theconstruction of flexible all-polymer-based conductive aerogels forpiezoresistive pressure sensors is often hindered by a trade-offbetween robust mechanical properties and elastic-responsiveconductivity. Here, a highly flexible and compressible conductiveaerogel was fabricated by integratingpoly(3,4-thylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS)with polyimide (PI) through facile strategies of freeze-drying andthermal annealing. With a controlled ratio of the two components, thecomposite demonstrates a well-ordered and interconnected porousstructure composed of “layer-strut” skeletons with linkedfibrils. Benefiting from the unique structure and synergistic effectsbetween the two polymers, the PEDOT:PSS/PI aerogel exhibits excellentcompressibility, stable and linear piezoresistive responses atvarious compressive strains and good reproducibility over 200 cycles.Furthermore, the hybrid can retain good compression sensitivity anddurable stability in severe environments, such as at high and lowtemperatures and under acidic conditions, demonstrating its greatpotential for a wide range of pressure sensor applications in harshenvironments.