A Luminescent Zinc(II) Metal–Organic Framework for Selective Detection of Nitroaromatics, Fe³⁺ and CrO₄²⁻: A Versatile Threefold Fluorescent Sensor

Abstract

A new ZnII metal–organic framework, [Zn6(L)3(DMA)4]⋅5 DMA (H4L=[1,1′:3′,1′′‐terphenyl]‐3,3′′,5,5′′‐tetracarboxylic acid, DMA=dimethylacetamide), has been synthesized and characterized. The structure contains a three‐dimensional 3,4,4,6‐connected net with (4.62)2(66)(66)(42.610.83) topology and displays selective detection of nitrobenzene, CrO42− and Fe3+ ions. The present work thus indicates that this metal–organic framework could be a prospective candidate for developing novel luminescence sensors for the selective sensing of nitrobenzene, which can be used as a precursor for explosives. Furthermore, the photoluminescent properties of this material in different solvents and with various analytes were investigated and corroborated by theoretical calculations. The results were in good agreement with the experimental solvent‐dependent luminescence behavior.

A 2D cadmium metal–organic framework: Synthesis, structure and luminescence sensing for chromate, permanganate, cupric, silver and ferric

“…The sensing abilities of 1•4H 2 O•DMAC for Cu 2+ , Ag + and Fe 3+ are comparable with these of the documented MOFs. [ 9–11,13–15,21–23,25,28,31,32 ] For example, {[Zn 5 (L) 2 (DMF) 2 (H 2 O) 2 ]·2DMF} (H 5 L = 3,5‐di(3′,5′‐dicarboxylphenyl)benzoic acid) exhibited the K sv of 1.10 × 10 3 M −1 , 2.24 × 10 3 M −1 and 4.49 × 10 4 M −1 for Cu 2+ , Ag + and Fe 3+ , and the detection limit of 1.01 ppm, 0.64 ppm and 1.30 ppm for Cu 2+ , Ag + and Fe 3+ . [ 9 ] {[Eu(2,7‐NDS)(IP)(OH)(H 2 O)]·mH 2 O} n (2,7‐NDS = 2,7‐naphthalenedisulfonate, IP = 1H‐imidazo[4,5‐f][1,10]‐phenanthroline) showed the high K sv of 1.19 × 10 5 M −1 and 1.18 × 10 5 M −1 for Fe 3+ and Ag + , and the detection limit of 0.277 μM and 0.272 μM for Fe 3+ and Ag + .…”

“…Therefore, the quenching mechanism of 1•4H 2 O•DMAC for Cr 2 O 7 2− , CrO 4 2− , MnO 4 − and Fe 3+ can be assumed to the energy‐transfer. [ 9–15,21–30 ] However, no overlap between the UV–visible absorption spectra of Cu 2+ , Ag + and other ions with the excitation and emission spectra of 1•4H 2 O•DMAC . N1s X‐ray photoelectron spectroscopy (XPS) studies showed that the N1s peaks from triazole nitrogen atoms in 1•4H 2 O•DMAC were at 399.8, 401.8 and 405.2 eV (Figure 13).…”

“…In the past decade, the luminescence sensors based on metal–organic frameworks have been developed for the detection of metal ions such as Fe 3+ and Ag + , inorganic anions, volatile organic molecules, and explosives. [ 9–20 ]…”

A microporous metal–organic framework with open metal sites for selective sensing Fe3+, CrO42- and nitrobenzene

“…A few of examples of porous MOFs with Lewis basic sites have been reported, including [Eu(btpca)(H 2 O)]·2DMF·3H 2 O [H 3 btpca = 1,1′,1″-(benzene-1,3,5-triyl)tripiperidine-4-carboxylic acid] with multiple Lewis basic triazinyl nitrogen atoms for the sensing of Fe 3+ ions [6], and [Eu 3 (bpydb) 3 (HCOO)(μ 3 -OH) 2 (DMF)]·(DMF) 3 (H 2 O) 2 [bpydbH 2 = 4,4′-(4,4′-bipyridine-2,6-diyl)dibenzoic acid] exhibits multi-responsive luminescence sensing of small organic molecules and inorganic ions [7]. These results highlight the significance of such Lewis basic sites within porous MOFs for their functional properties [8][9][10][11][12][13].…”

Effect of synthesized temperature on the assembly and properties of four lanthanide supramolecular frameworks

“…The luminescent intensity of 4 decreased to 98% at 160 ppm (Figure 6c). Following the 3δ/slope, the TNP detection limit is calculated to be 1.99 ppm [18][19][20]. The quenching constant and limit of detection for TNP by 4 were found to be comparable with the reported LMOF detection of TNP at the ppb level using MOFs [21][22][23], excluding the lowest detection limit so far reported, by Ghosh et al (LOD = 2.9 ppb (12.9 nM, K SV 4.6 × 104 M −1 ) using bio-MOF) [23].…”