Biomimetic Strawberry-Structured Micro/Nano Fibers as Positive Friction Layers for High-Performance Triboelectric Nanogenerators

Electrospun triboelectric nanogenerators (TENGs) are favored in flexible, wearable devices. In this article, the positive friction layers of TENGs with biomimetic strawberry structures were efficiently prepared using free-surface electrospinning technology. The dielectric constant of multistrawberry-structured (MSS) micro/nano fibers with the highest specific surface area was increased by about 1.5 times, significantly enhancing the charge-trapping ability of positive friction layers. Subsequently, the effects of fiber microstructure, contact area, membrane thickness, external force, air gap, and frequency on the output properties of MSS-TENG were explored. The optimal device performed well at 25 N and 3 Hz, with an open-circuit voltage of 301.93 V, a short-circuit current of 7.34 μA, a transfer charge of 103.89 nC, and a power density of 0.617 W/m², lighting up 300 light-emitting diodes and driving portable electronic devices to operate normally. Moreover, MSS-TENG could maintain stable output after nearly 40 min of cycling.