Self-Template Hydrothermal Synthesis of Vinylene-Linked Covalent Organic Framework Nanosheets Confined at the Molecule/Water Interface for an Organic Memristor

Vinylene-linked covalent organic frameworks (COFs) are traditionally synthesized through solvothermal methods using organic solvents. However, the laborious process of optimizing solvent ratios and the environmental harm caused by organic solvents constrain the facile and large-scale synthesis of COFs. Consequently, employing water as an environmentally benign reaction medium is highly desirable for synthesizing chemically stable vinylene-linked COF materials. In this study, we report a novel self-template hydrothermal approach for preparing vinylene-linked COF nanosheets via the molecule/water interfacial Knoevenagel condensation. These nanosheets exhibit substantial resistance to both acids and alkalis. The vinylene-linked COF-based memristor demonstrated characteristic nonvolatile rewritable memory effects, featuring a small switch-on voltage of -0.65 V and an ultrafast switching speed of 120 ns. Benefiting from the chemical durability of the COF nanosheets, the memristor maintained excellent stability in switching and retention performance after the acid and base treatments. Moreover, the vinylene-linked COF-based memristors successfully performed "AND" and "OR" logic operations, demonstrating their potential for advanced computing applications.