Clothing comfort sensing system based on triboelectric and tribological behavior of fabrics

Static electricity accumulated on fabrics often causes discharged discomfort, fire, explosion, and cardiovascular
diseases. Meanwhile, the electricity can be harvested and used for self-powered wearable devices. Therefore, it is
essential to regulate fabric triboelectricity through studying the relationship between friction coefficients and
triboelectric charges. In this paper, a reciprocating tribometer coupled with triboelectric testing instruments is
designed to collect in-situ tribological and triboelectric properties for laterally sliding fabric based triboelectric
nanogenerators (F-TENGs). In this case, the regulation factors involve motion conditions (including load, fre
quency, friction angle, etc.), surface components and environments. The results show that faster sliding speed
and lower humidity produce higher triboelectric outputs of F-TENGs. Especially, amino groups modified silk
shows an extremely strong electron-donating ability and achieves a high triboelectric current of 382.2 nA when
paired with polyimide, which is enhanced by 1.67 times compared with silk. Most importantly, the friction
coefficient values of F-TENGs show almost the same trend as the triboelectric outputs. Based on this, a sensing
system for monitoring comfort level of fabrics is successfully designed through rubbing tested fabrics and
observing indicator lamps. This work proposes a tribological approach with valuable insights of the underlying
mechanism of triboelectric charging and extended applications.