Cotton-assisted dual rotor-stator triboelectric nanogenerator for real-time monitoring of crop growth environment

Employing clean and sustainable wind energy to build a sensor system is of critical importance for the currently thriving smart agriculture and the goals of carbon peaking and carbon neutrality, as an essential driving force for rural revitalization. Triboelectric nanogenerators (TENGs) exhibit broad applications in sensor networks as power sources owing to the advantages of irregular and distributed energy harvesting. However, TENGs suffer from the problems of limited average power density and durability, which motivate us to design the soft-contact flower-bud array cotton-based TENG (SFC-TENG) with the rotation of a double rotor-stator structure for harvesting wind energy. The adopted cellulose-rich cotton-assisted soft-contact and double rotor-stator structure with multiple contact areas endow SFC-TENG with excellent performance in triboelectrification, which is beneficial for reducing frictional resistance and prolonging the lifetime. The assembled TENG device reveals excellent output performances with high open-circuit voltage of 2500 V, short circuit current of 85 μA, and maximum output power of 80 mW. Especially, high durability is achieved with no significant degradation of output performance after 320,000 cycles. The prominent properties confirm that the SFC-TENG is feasible for powering smart farming in night lighting, pH detection, and temperature/humidity monitoring. This work provides an effective strategy combining design of the double rotor-stator structure with the flexible contact of cotton, which is of great inspiration for the exploitation of high-performance TENGs for smart agriculture application.