Scalable wet-spinning multilevel anisotropic structured PVDF fibers enhanced with cellulose nanocrystals-exfoliated MoS2 for high-performance piezoelectric textiles

The high-performance fabric-based piezoelectric nanogenerators (PENGs) is the ideal choice for the next generation of wearable electronics. However, large-scale fabrication of high-performance fabric-based PENGs remains a great challenge. In this study, cellulose nanocrystals (CNCs) exfoliated MoS2 (C@M) are integrated into the poly (vinylidene fluoride) (PVDF) matrix, which are successfully fabricated PVDF/C@M fibers (PCF) by wet-spinning and post-drawing processes. Accompanied by the stress-induced anisotropic alignment of C@M and PVDF molecular chains during post-drawing, the interfacial interactions between C@M and PVDF dipoles greatly promote the formation of the electroactive beta-phase of PVDF as well as the orientation of the dipoles. The PCF demonstrate excellent mechanical performance with a tensile strength of 301 MPa and toughness of 68.5 MJ center dot m(-3). Subsequently, the PCF are woven into fabrics and subsequently assembled into a flexible PENG (PCF-PENG), exhibiting excellent piezoelectric coefficient (d(33) = 40.3 pC center dot N-1), power density of 56.25 mu W center dot cm(-2). Furthermore, scenarios such as energy harvesting, motion detection, and posture recognition of the PCF-PENG are demonstrated, providing a feasible proposal for the large-scale fabrication of electronic textiles.