Self-poled and transparent polyvinylidene fluoride- co-hexafluoropropylene-based piezoelectric devices for printable and flexible electronics

Nanoscale. 2023 Mar 2;15(9):4581-4590. doi: 10.1039/d2nr05986j.

Abstract

Transparent and flexible energy supply devices are becoming increasingly important for human interfaces as the Internet of Things (IoT) continues to grow. In this study, self-poled and transparent piezoelectric nanogenerators (ST-PENGs) based on 1H,1H,2H,2H-perfluorodecyltriethoxysilane (PFOES) and polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) composite films were prepared via extrusion printing, where PFOES induces the transformation of PVDF-HFP chains, exhibiting a higher β-phase content and remarkable piezoelectric properties. The hydrogen bonding interaction between the PVDF-HFP matrix and the PFOES agents causes a clear transition from phase to phase, as evidenced by Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) results. Moreover, the PFOES content influences the β-phase content, with 10 wt% of PFOES enabling the induction of the β-phase content up to 82.7%. The proposed ST-PENGs generate an excellent output voltage, power, and sensitivity of ∼6.2 V, ∼6.9 μW cm-2, and ∼131.3 mV N-1, respectively, exhibiting a record-high improvement compared with previously reported PENGs. These ST-PENGs also offer significant promise in tracking human activity and recovering biomechanical energy. This study may provide insight into the development of transparent and flexible piezoelectric devices to achieve high-performance self-powered electronics.