2D Boron Nitride Nanosheets in Polymer Nanofibers for Triboelectric Nanogenerators with Enhanced Performance and Flexibility

Poly(vinylidene fluoride) (PVDF)-based triboelectric nanogenerators (TENGs) have attracted much attention in recent years because of their high efficiency of energy conversion and high plasticity for structural shaping. Here, an electronegative layer is first fabricated by incorporating exfoliated 2D hexagonal boron nitride nanosheets (hBNNSs) into PVDF nanofibers (NFs) and then assembling them with an electropositive layer composed of nylon-11 NFs to obtain the PVDF-based TENG, which shows high flexibility owing to the all-fiber-structured layers. The effect of various concentrations of hBNNSs on the TENG's structure and properties is investigated. The results show that the performance of the TENG with 0.5 wt % hBNNSs is dramatically enhanced because of the incorporation of hBNNSs with superior piezoelectricity and large specific surface area in favor of the conversion of mechanical energy to electric energy. As a result, the open-circuit voltage (VOC) and short-circuit current (ISC) of the TENG reach as high as 500 V and 25.2 μA, respectively, resulting in a record-high power density of 3.13 W/m2, better than the previously reported values of PVDF-based TENGs. Finally, the TENG is used to drive electronics as a power source and to monitor human body motion in real time as a flexible wearable sensor, indicating its feasibility in sustainable and wearable electronics.