Fully Transparent Flexible Piezoelectric Sensing Materials Based on Electrospun PVDF and Their Device Applications

Abstract

Advanced transducer materials have become increasingly important with the rapid development of the internet of things and flexible electronics. Herein, fully transparent flexible polyvinylidene fluoride/polydimethylsiloxane (PVDF/PDMS) composite piezoelectric films are fabricated using scrape coating techniques based on electrospun PVDF nanofiber films. Compared to the electrospun PVDF, the PVDF/PDMS not only owns high transparency and a more uniform and stable structure but also has superior piezoelectric properties. Based on the electrospun PVDF and the PVDF/PDMS films, flexible piezoelectric sensors are developed, which can effectively detect weak mechanical signals including finger tapping and bending signals, radial artery pulses, and environmental sound signals. The PVDF/PDMS sensor performs better than the electrospun PVDF sensor and presents great potential for applications in flexible sensors and transducers. Especially, thanks to their high transparency, the PVDF/PDMS composite piezoelectric films lend themselves easily to application fields requiring transparent sensors such as imperceptible sensors and human‐machine interfaces, display devices, electronic skins, intelligent windows, etc.

Piezoelectric Enhancement in P(VDF-TrFE) Copolymer Films via Controlled and Template-Induced Epitaxy

“…Scattering of visible light at both crystalline/amorphous interface and film/air interface results in the attenuation of light transmittance . In fact, transparency attenuation due to interface scattering has been reported in electrospun PVDF nanofibers where numerous fiber/air interfaces result in opaque nanofiber membranes …”

“…30 In fact, transparency attenuation due to interface scattering has been reported in electrospun PVDF nanofibers where numerous fiber/air interfaces result in opaque nanofiber membranes. 31 The piezoelectric performance of those epitaxial films is further quantified using a homemade longitudinal piezoelectric measurement system (Figure 4a). Piezoelectric polymer capacitors are securely positioned between a commercial quartz force sensor and a vibration stage.…”