Ultra-sensitive All Organic PVDF-TrFE E-spun Nanofibers with Enhanced Β-Phase for Piezoelectric Response

The use of piezoelectric materials has been increased due to the growing demand for wearable devices. Herein, we report the development of new copolymer poly (vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE)-based reduced graphene oxide (rGO) and multiwalled carbon nanotubes (MCNTs) loaded electrospun (E-Spun) nanofibers. The rGO-MCNTs loaded PVDF-TrFE nanofibrous mat led to the fabrication of ultra-sensitive piezoelectric pressure sensors for potential wearable health monitoring applications. The doped PVDF-TrFE solution of different weight percentages of rGO-MCNTs as fillers was prepared and used to fabricate an e-spun nanofibrous mat. Complete characterization of resultant materials were carried through diverse instruments which reveals the successful integration of rGO-MCNTs (3.2%) as a dopant that improved the β-phase up to 92%. The DSC analysis further exposes the high thermal stability of the PVDF-TrFE nanofibers mat due to the enhanced crystallinity with the addition of nanofillers. The newly developed sensor’s overall output (based on sensitivity) was calculated under a variable applied pressure range of 0.25 ~ 300 cN at 50 HZ. Results show that the pressure sensor response has improved from 16.125 ~ 0.430 kPa−1, corresponding to a higher sensitivity under static and dynamic forces in the applied pressure range. These results are of a fundamental study and open new prospects for the hybrid nanofibrous mat as alternative electrode material in the piezoelectric pressure sensor.