Durable flexible direct current generation through the tribovoltaic effect in contact-separation mode†
Abstract
The tribovoltaic effect at dynamic semiconductor interfaces has been an emerging hot topic due to its potential impact in energy harvesting and smart electronics. Previously, this effect was mainly studied based on the sliding mode and is undesirably accompanied by abrasion issues. Herein, we demonstrate the tribovoltaic effect based on the contact-separation motion of a dynamic Schottky interface, and achieve durable, flexible and high-performance direct-current electricity generation. The generator is designed based on a flexible organic semiconductor, achieving a high current density of 16.00 A m−2, a charge density of 98.72 mC m−2, and a peak power density of up to 5.40 W m−2 in contact-separation mode. Most importantly, long-term durability is demonstrated without performance degradation in 20 000 cycles, as the undesirable abrasion in the sliding mode is avoided. Furthermore, investigation of the tribovoltaic effect in contact-separation mode helps achieve better mechanistic understanding, that the contact-induced “bindington” is more likely to provide the energy for electron excitation. Therefore, this study presents both practical and fundamental insights for tribovoltaic devices.