A Sensitive Fluorescence Probe for the Trace Detection of Fe(III) Based on a Post‐Synthesis‐Modified Copper‐Based Metal‐Organic Framework

Abstract

This work presents the generation of a post‐synthetically modified Metal‐Organic Framework (MOF), denoted as Cu‐BDC‐NH2‐DHB, achieved through a Schiff‐base reaction by converting the pendant amino group in pristine Cu‐BDC‐NH2 MOF to an imine group using 3,4‐dihydroxybenzaldehyde (DHB). The resulting material exhibited exceptional luminescence and fluorescence stability in water, prompting investigation into its potential as a metal sensor. Fluorescence tests revealed that Cu‐BDC‐NH2‐DHB could be transformed into a highly selective and sensitive sensor for detecting Fe3+ ions amid co‐interfering metal ions, with a remarkable detection limit of 3.08 μM. Furthermore, the results demonstrated that Fe3+ induced a rapid and strong quenching effect, with a reaction time measured in seconds. This research provides a promising technique for the facile and immediate detection of Fe3+ ions in practical applications.