A Dye@MOF composite as luminescent sensory material for selective and sensitive recognition of Fe(III) ions in water

Abstract

Dye encapsulated metal-organic framework (MOF) composites have emerged as one of the promising platforms toward chemical recognition. Herein, a highly potent hydrolytically stable luminescent sensory probe was crafted exhibiting selective fluorescence response for Fe3+ ions in water medium. Encapsulation of a cationic dye inside a porous anionic MOF was successfully achieved via an ion-exchange process. Confinement of dye molecules inside the MOF serving as a crystalline flask prohibits the aggregation-induced quenching of dye molecules thereby manifesting a Dye@MOF luminescent composite material. The Dye@MOF composite shows selective response toward Fe3+ ions with remarkable luminescence quenching even in presence of other metal ions. Additionally, a high K-sv (quenching coefficient) value of 5.5 x 10(4) M-1 and low limit of detection (LOD) of 1.1 ppm was observed for Fe3+ ions.