Ru(N^N)3-docked cationic covalent organic frameworks for enhanced sulfide and amine photooxidation

Abstract

Covalent organic frameworks (COFs) have emerged as significant candidates for visible-light photocatalysis due to their ability to regulate performance which is achieved through the careful selection of building modules, framework conjugation, and post-modification. This report focused on the efficient transformation of an imine-linked I-COF into a π-conjugated quinoline-based Q-COF, which enhanced both the chemical stability and conjugation of the network. By methylating the pyridyl groups in the Q-COF, an N⁺-COF was obtained. Subsequently, the Ru(N^N)₃-photosensitizer ([Ru(dcbpy)₃]⁴⁻) was incorporated into the channels of the cationic N⁺-COF through electrostatic interactions, resulting in the formation of [Ru(dcbpy)₃]⁴⁻⊂N⁺-COF. This composite exhibited exceptional photocatalytic activity, demonstrating high yields and selectivity in the oxidation of sulfides or amines to their respective products.