Covalent organic frameworks (COFs) are a new class of porous organic materials, which are prepared with organic building units via strong covalent bonds. Their well-defined crystalline porous structures together with special functionalities have endowed COF materials with important potential in wide applications, such as gas storage, adsorption, optoelectricity, catalysis and chemical sensing. Particularly, the fluorescence properties and the sensing applications of COF materials have attracted wide attention of analysts. This critical review presents the important development in the design, synthesis and analytical application of fluorescent COF materials as well as the investigation of luminescence characteristics.

Sensitive turn-off mode fluorescence sensing for Fe³⁺based polyimide bond linked COFs.