Covalent Organic Frameworks with Tailored Functionalities for Modulating Surface Potentials in Triboelectric Nanogenerators

Angew Chem Int Ed Engl. 2022 Oct 17;61(42):e202211601. doi: 10.1002/anie.202211601. Epub 2022 Sep 19.

Abstract

Designing materials with high triboelectric is an efficient way of improving output performance of triboelectric nanogenerators (TENGs). Herein, we synthesized a series of covalent organic frameworks (COFs) with similar skeletons but various functional groups ranging between electron-donating and electron-withdrawing. These COFs form an ideal platform for clarifying the contribution of each group to TENG performance because the pore wall is perturbed in a predesigned manner. Kelvin probe force microscopy and computational data suggest that surface potentials and electron affinities of COFs can be improved by introducing electron-donating or withdrawing groups, with the highest values observed for fluorinated COF. The TENG with fluorinated COF delivered an output voltage and current of 420 V and 64 μA, respectively, which are comparable to other reported materials. This strategy can be used to efficiently screen suitable frameworks as TENG materials with excellent output performance.

Keywords: Built-in Functionalities; Covalent Organic Frameworks; Self-Powered Anticorrosion; Surface Potential; Triboelectric Nanogenerators.