Stretchable and Tailorable Triboelectric Nanogenerator Constructed by Nanofibrous Membrane for Energy Harvesting and Self-Powered Biomechanical Monitoring

Wearable triboelectric nanogenerators (TENGs) with both functionality and comfort have become an appealing field of research for portable electronic devices recently. Here, a breathable, stretchable, and tailorable TENG that enables both energy harvesting and biomechanical monitoring is designed. Two layers of nanofiber membranes, which consist of polyvinylidene fluoride supported by conducting fabric and thermoplastic polyurethanes (TPU) supported by Ag elastic fabric, are welded into arch structures through ultrasonic welding technique. As the bottom layer of the arch, the TPU/Ag layer with consistent stretchability guarantees the stretchable of the TENG. Therefore, the TENG can collect various types of irregular movements, such as stretching, pressing, and twisting motions, even the combination of the above all motions. Under twisting stretch, the open-circuit voltage and short-circuit current of one basic unit can reach up to 170 V and 4.5 mu A, respectively. Besides, the welded TENG is tailorable and it still maintains certain output even if it is partially cut or damaged. The continuous arch-structured TENGs can also be used as self-powered motion sensors to constantly monitor the intensity and frequency of human body movements. Thus, this work opens up a new idea for preparation of wearable TENG with both multifunction and better comfort.