Cationic Covalent Organic Frameworks for Fabricating an Efficient Triboelectric Nanogenerator

Covalent organic frameworks (COFs) have developed as a precisely tailor-made platform for integrating different functionalities into the frameworks via reticular chemistry. In this work, two COFs with a similar topology and skeleton but different charge state over the skeleton are designed and applied to clarify the contributions of cationic groups to the output performance of a triboelectric nanogenerator (TENG). The cationic functional centers are distributed alternately over both sides of the pore channels. The cationic COF possesses unconventional electrostatic functions due to the ionic interface over the skeletons. The output performance of a cationic COF decorated with an electric-dipole-based TENG is improved by a 2-fold contrast to the neutral analogue. Moreover, a cationic COF-based TENG is further employed to charge commercial capacitors (0.1 F), light up light-emitting diodes (LEDs), and power a stopwatch. This work illustrates the facile construction of a cationic COF and its application in fabricating a TENG, generating an ecofriendly and excellent-performance energy harvesting and self-powered device.