A roller-type triboelectric nanogenerator based on rotational friction between wool and stacked interface for omnidirectional wind energy harvesting

It is urgently desired to develop high-performance wind energy collectors to power numerous microelectronic devices along with the Internet of Things (IoT). A roller-type triboelectric nanogenerator (R-TENG) based on rotational friction between wool and stacked interfaces is proposed and efficiently used for harvesting wind energy. Wool, an electropositive and flexible material, is utilized in the design, effectively reducing abrasion on the contact surface and adjusting the output in response to varying compression levels. The conductive layer greatly enhances the output performance, which produces more induced charge by stacking different triboelectric materials in a particular order. By adding bottom power generation units, the internal space of the unit can be fully utilized to improve its energy conversion efficiency. At 900 rpm of the motor, the instantaneous open-circuit voltage (