Flexible electrically conductive biomass-based aerogels for piezoresistive pressure/strain sensors

Flexible, compressible and conductive aerogels were fabricated by incorporating polyaniline (PANI) into bacterial cellulose/chitosan (BC/CH) composites through facile freeze-drying technique. The PANI/BC/CH aerogel fabricated with the BC:CH weight ratio of 1:1 displayed the highest resistance response and showed extremely high sensitivity (1.41 kPa−1), low pressure detection (32 Pa), wide range of pressure deformation and extraordinary stability as a piezoresistive sensor. Polydimethylsiloxane (PDMS) was embedded into PANI/BC/CH aerogels to form PANI/BC/CH PDMS composites that displayed good stability under large mechanical deformation. Furthermore, applications of PANI/BC/CH aerogels and PANI/BC/CH/PDMS composites in piezoresistive sensors for wearable devices were also reported, which could detect human motions, ranging from joint movement to speech recognition, thus suggesting feasibility in health monitoring systems.