A luminescent sensor based on a Zn(ii) coordination polymer for selective and sensitive detection of NACs and Fe3+ ions

Abstract

To design an effective fluorescence probe for sensing nitroaromatic compounds (NACs) and metal ions, a novel two-dimensional (2D) coordination polymer, {Zn₂(NO₃)₂(4,4′-bpy)₂(TBA)} (1) {H₂TBA = 4-(1H-tetrazol-5-yl)-benzoic acid, 4,4′-bpy = 4,4′-bipyridine} was synthesized via a hydrothermal method. As expected, 1 presented varying degrees of fluorescence intensity changes for detecting and recognizing trace NACs with high selectivity and sensitivity in water solution. Moreover, 1 not only exhibited a highly selective fluorescence quenching effect on Fe³⁺ ions in aqueous solution, but could also resist the interference of various other metal ions. In addition, it has been found that the fluorescence quenching mechanisms among NACs and Fe³⁺ ions are mainly related to the interactions between the host group and guest molecules by energy and electron transfer.