Screw Pump‐Type Water Triboelectric Nanogenerator for Active Water Flow Control

Triboelectric nanogenerators (TENGs) have been spotlighted due to the high efficiency, low cost, and easy accessibility. Despite their advantage, TENGs exhibit certain limitations such as a low lifetime. To overcome the limitation, the use of water–solid contact TENGs has been suggested. Most of the studies about water–solid contact TENG are focused on optimizing the device to adjust to the stagnant water or natural water movement. However, in most actual fluid machinery applications, the flow of water can be changed by mechanical components. The development of the water–solid contact TENG that actively changes water movement can broaden the application of TENGs. Herein, a screw pump TENG (SP–TENG) that can generate electricity by pumping water is developed. By analyzing contact surface area between water and screw in different screw rotational velocity and electrical difference from different electrode area, the device is able to optimize. The developed SP–TENG can light four light‐emitting diodes (LEDs) and activate temperature sensor. In addition, because SP–TENG can function as an active water TENG, it can enable the circulation of water to improve the ecosystem. Thus, SP–TENG can be used as an ecofriendly device that can simultaneously harvest energy and induce self‐purification of water.