Wearing comfortable and high electrical output TENGs woven with PTFE core–shell nanofiber yarns

As an energy output device, triboelectric nanogenerators (TENGs) have greatly promoted the application of wearable electronics, particularly in energy harvesting and human motion monitoring. However, the TENGs applied in wearable electronics require not only high electrical output performance but also wearable comfort. This paper provided a polytetrafluoroethylene (PTFE) nanofiber yarn-based TENGs. The prepared nanofiber yarn featured a core–shell structure, with PTFE/graphene nanofibers forming the friction shell layer while a copper wire serving as the conductive core layer. When the graphene content reached 2 wt%, the resulting woven fabric (GW-TENG-2) showed the best comprehensive performance. The GW-TENG-2 exhibited high air permeability (air flux 1618.9 mm·s⁻¹ @ 10 kPa), outstanding self-cleaning properties, as well as stable washing resistance (no changes in voltage after five washes). Meanwhile, the GW-TENG-2′s open-circuit voltage (Voc), short-circuit current (Isc), and maximum instantaneous power density reached 206 V, 16.3 μA, and 1.04 W/m², respectively, demonstrating its excellent electrical output performance. Consequently, it successfully powered 180 light-emitting diodes (LEDs) and was capable of charging commercial capacitors and electronic watches. Furthermore, by attaching GW-TENG-2 to different human body parts (throat, fingers, elbow, etc.), the movement of these regions could be effectively monitored. For instance, in the case of the human finger, the resulting voltage signal varied from 0.4 V to 1 V as the fingertip bent from 30° to 90°. These results highlighted that GW-TENG-2 held significant potential for applications in wearable electronics, particularly for energy harvesting and motion monitoring.