A Viologen-Based MOF: Photoresponsive Discoloration Property and Selective Fluorescence Detection of Nitrofurans and Lysine

A metal–organic framework featuring a 3-fold interpenetrating diamondoid structure has been constructed utilizing a viologen derivative, 1,1′-bis(4-carboxyphenyl)-(4,4′-bipyridinium) dichloride. This compound demonstrates good performance as a multifunctional colorimetric and fluorescence sensor. The incorporation of viologen imparts the compound with a visible photoresponsive discoloration property. Furthermore, this compound exhibits the ability to detect nitrofurans and lysine through fluorescence turn-off and turn-on mechanisms, respectively.