Self-boosted power generation of triboelectric nanogenerator with glass transition by friction heat

Inevitable frictional heat, generated by friction, degrades output performance of polymer-based triboelectric nanogenerators (TENGs). To address this issue, we propose to take advantage of using shape memory effect of polyurethane (PU) as a triboelectric layer to not only operate TENG sustainably, but also realize self-boosting power generation performance of TENG by frictional heat. We found that frictional heat sufficiently leads to the glass transition of PU and this transformed PU at elevated temperature contributes to change key parameters, serving to improve performance of TENG, including dielectric constant, work function, and charge trap density. In this work we verified PU harness heat generated by friction and demonstrated 300% increase of the powergenerating performance of PU-based TENG with experiencing the glass transition. In addition, we experimentally observed no further temperature elevation around 60 degrees C in TENG with a continuous rotating friction mode, which offers PU potential to be a promising triboelectric material for high performance TENGs.