Roll to roll triboelectric fiber manufacturing for smart-textile self-powered sensor and harvester

Abstract

The integration of a multifunctional electronic textile-based triboelectric nanogenerator (TENG) with miniaturized devices has opened up a new horizon in the field of wearable electronics. Unfortunately, the development of textile based TENG has enormous shortcomings, including shortcomings in durability, stability, washability, and compatibility with mass production. Thus, this work reports a cost-effective, simple fabrication, and industrially scalable production method of producing fiber TENG using silver conductor fiber encapsulated by polydimethylsiloxane (PDMS). To produce continuous PDMS-coated silver fiber, a home-made coating technology was used, in which silver fiber was fed up through a nozzle filled with PDMS gel solution using a roll-to-roll continuous fabrication process. The feasibilities of TENG fiber production were demonstrated by the manufacturing of over 300-meter-long fibers and therefrom a half-meter-long TENG woven fabric of 20 cm width including the integration technique into wearable garments for self-powered sensors and harvesters. The maximum output open circuit voltage and short circuit current of the PDMS-coated silver triboelectric nanogenerator (PS-TENG) were ∼50 V and ∼8.0 μA from 50.0 cm-long and 0.55 mm diameter fiber. A PS-TENG coil harvester out of this fiber can easily light up 160 LEDs with simple hand tapping. We also demonstrated the PS-TENG integration on the heel of a shoe insole, which was also able to light up 25 LEDs in serial connection during walking. Furthermore, since the PS-TENG provides flexibility and excellent durability against washing, repeatable uses, rubbing, and stability in harsh chemical environments, we have also integrated the self-powered sensor fiber into various healthcare objects and wearable sports items, including hand gloves for cardiopulmonary resuscitation sensing (CPRS), a belt for respiration sensing, and a belt for football shoes and boxing gloves to evaluate the impact of kicking and boxing. All these advantages of PS-TENG not only enable small wearable electronics to be powered but also accelerate the development of industrially scalable energy harvesting through engineering design.