Turn-on Solid-State Fluorescent Determination of Zinc Ion by Quinoline-based Covalent Organic Framework.

A new quinoline-based COF (Covalent Organic Framework), obtained by Povarov reaction, containing 2,6-diisopropylphenyl moieties as substituents over the heterocyclic ring is described for detecting Zn 2+ in aqueous solution. The introduction of the mentioned bulky phenyl rings into the network favors an increase of the distance between the reticular sheets and their arrangement, obtaining a new material with an alternating AB type stacking. The new material exhibits good selectivity to detect Zn 2+ by fluorescence emission in aqueous solutions up to a concentration of 1.2 × 10 ꟷ4  M of the metal ion. In order to have a deeper insight into the interaction between the COF and the zinc cation, a thorough spectroscopical, microscopical and theoretical study is also presented and discussed in this communication. This article is protected by copyright. All rights reserved.