Electric field-induced intramolecular charge transfer of two-dimensional covalent organic frameworks with D–A systems for organic memristors

Abstract

Covalent organic frameworks (COFs) containing D–A systems, which showed excellent performance in various fields and have high designability, are considered one of the most promising functional layer materials for high-performance organic memristors. Herein, two two-dimensional COF films containing D–A systems, namely, TT-COF and BT-COF, were rapidly synthesized at room temperature through a reversible Schiff-base reaction. The rewritable memristor based on a 51 nm TT-COF exhibited high stability (550 cycles and 10⁴ s) and low driving voltage (0.8 V), and its good non-volatile resistance switching behavior was attributed to the electric field-induced intramolecular charge transfer within the D–A system. By comparing with memristive devices using the same COF as the functional layer, our speculation on the conductivity mechanism was further confirmed.