Kim Yeongjun, Wu Xinwei, Oh Je Hoon
Department of Mechanical Engineering, Hanyang University, Ansan, Gyeonggi-do, 15588, Republic of Korea.
Sci Rep. 2020 Feb 17;10(1):2742. doi: 10.1038/s41598-020-59546-7.
Surface modification of polyimides (PIs) using electrospinning would significantly improve the performance of TENGs because of the larger surface area of the electrospun friction layer. However, PIs generally have high solvent resistance, so it is complicated to convert them into nanofibers using electrospinning process. This study aims to fabricate PI nanofibers via simple, one-step electrospinning and utilize them as a friction layer of TENGs for better performance. PI nanofibers were directly electrospun from PI ink made of polyimide powder without any additional process. The effect of PI concentration on spinnability was investigated. Uniform and continuous nanofibrous structures were successfully produced at concentrations of 15 wt% and 20 wt%. Electrospun PI nanofibers were then utilized as a friction layer for TENGs. A TENG with 20 wt% produced an open circuit voltage of 753 V and a short circuit current of 10.79 μA and showed a power density of 2.61 W m at a 100 MΩ load resistance. During tapping experiment of 10,000 cycles, the TENG could stably harvest electrical energy. The harvested energy from the proposed TENG is sufficient to illuminate more than 55 LEDs and drive small electronic devices, and the TENGs exhibit excellent performance as a wearable energy harvester.
由于静电纺丝摩擦层具有更大的表面积，利用静电纺丝对聚酰亚胺（PI）进行表面改性将显著提高摩擦电纳米发电机（TENG）的性能。然而，PI通常具有高耐溶剂性，因此使用静电纺丝工艺将其转化为纳米纤维很复杂。本研究旨在通过简单的一步静电纺丝制备PI纳米纤维，并将其用作TENG的摩擦层以获得更好的性能。PI纳米纤维是直接从由聚酰亚胺粉末制成的PI油墨中静电纺丝得到的，无需任何额外工艺。研究了PI浓度对可纺性的影响。在15 wt%和20 wt%的浓度下成功制备出均匀连续的纳米纤维结构。然后将静电纺丝的PI纳米纤维用作TENG的摩擦层。含20 wt%的TENG产生的开路电压为753 V，短路电流为10.79 μA，在100 MΩ负载电阻下的功率密度为2.61 W m 。在10000次循环的敲击实验中，该TENG能够稳定地收集电能。从所提出的TENG收集的能量足以点亮55个以上的发光二极管（LED）并驱动小型电子设备，并且该TENG作为可穿戴能量收集器表现出优异的性能。
