Effect of phenyl-isocyanate functionalized graphene oxide on the crystalline phases, mechanical and piezoelectric properties of electrospun PVDF nanofibers

Abstract

Owing to their good flexibility, biocompatibility, and capability to convert mechanical energy to electrical energy, electrospun poly(vinylidene fluoride) nanofibers (PVDFNFs) have attracted considerable attention for energy harvesting as well as wearable and self-powered electronics. However, inadequate mechanical strength and low piezoelectric output are major concerns for their practical application. Herein, we report an effective method for fabricating mechanically robust PVDFNFs with enhanced piezoresponse by incorporating phenyl-isocyanate functionalized graphene oxide (IGO) as an efficient nanofiller. The presence of IGO endowed PVDFNFs with a rough surface morphology, enhanced crystallinity, and electroactive β phase. Excitingly, enhancements of 303% and 332% in the ultimate tensile strength and modulus, respectively, were achieved for the IGO-incorporated PVDFNFs. Furthermore, the acoustic sensitivity of the composites was 63.09% higher than that of the pristine PVDFNFs. The composites had a minimum sensing force of 0.012 N, which was 20% less than the minimum sensing force of the pristine PVDFNFs. The incorporation of IGO enhanced the power generation capability of the composites by 55.23% compared with that of the pristine PVDFNFs. Thus, the as-prepared composites hold great promise for the fabrication of mechanically robust, high-performance piezoelectric composites for mechanical energy conversion applications.