A triboelectric nanogenerator based on TPU/PVDF electrospinning for mechanical energy harvesting and monitoring running step rate

Wearable fiber flexible sensors for sports motion monitoring have recently received attention. However, wearable flexible sensors still face limitations in material and device design. Here, we proposed a thermoplastic polyurethane (TPU)/polyvinylidene fluoride (PVDF) film as triboelectric material to manufacture triboelectric nanogenerator (TP-TENG) for harvesting mechanical energy and athlete step rate monitoring. The TPU/PVDF fiber film can be fabricated by using electrospinning technology. In addition, the role of negative triboelectric materials is played by TPU/PVDF film, and the nylon film acts as a positive triboelectric material. The TP-TENG device follows a single-electrode working mode, and it is easy to integrate into human clothing. The TP-TENG electrical output can achieve the maximum output when the content of PVDF in TPU/PVDF film reaches 15%. The TP-TENG can acquire the maximum output power of 699 µW under a 7 MΩ load. Also, the TP-TENG can be used as an electronic skin to achieve self-powered pressure sensing, and the sensitivity of the pressure sensor based on TP-TENG can reach 14.08 V N−1. By integrating it inside the shoes, TP-TENG can obtain the pace rate of runners for sports motion monitoring. This research reports an effective method for monitoring step rate in running and has potential application value.