A 3D luminescent Zn(ii) MOF for the detection of high explosives and the degradation of organic dyes: an experimental and computational study

Abstract

A new metal–organic framework, formulated as {[Zn₂(L)(DMF)₃]·2DMF·2H₂O} (1), has been synthesized using a symmetrical rigid carboxylate ligand terphenyl-3,3′′,5,5′′-tetracarboxylic acid (H₄L). Single-crystal X-ray diffraction analysis shows that 1 possesses a 3D uninodal 4-c lonsdaleite (lon) topology based on binuclear Zn clusters. 1 behaves as a fluorescent chemosensor for highly selective and sensitive detection of Fe³⁺/Fe²⁺ ions, 2,4-dinitrophenol (2,4-DNP), p-nitrophenol (PNP) and 2,4,6-trinitrophenol (TNP). Furthermore, the photocatalytic properties of 1 for degradation of methyl violet (MV) and Rhodamine B (RhB) have been explored. The possible emission quenching of 1 in the presence of aromatic compounds has been addressed by theoretical calculations and the photocatalytic activity of 1 against organic dyes has been addressed using density of states (DOS) calculations.