Tuning the Luminescence of Metal–Organic Frameworks for Detection of Energetic Heterocyclic Compounds

Abstract

Herein we report three metal-organic frameworks (MOFs), TABD-MOF-1, -2, and -3, constructed from Mg(2+), Ni(2+), and Co(2+), respectively, and deprotonated 4,4'-((Z,Z)-1,4-diphenylbuta-1,3-diene-1,4-diyl)dibenzoic acid (TABD-COOH). The fluorescence of these three MOFs is tuned from highly emissive to completely nonemissive via ligand-to-metal charge transfer by rational alteration of the metal ion. Through competitive coordination substitution, the organic linkers in the TABD-MOFs are released and subsequently reassemble to form emissive aggregates due to aggregation-induced emission. This enables highly sensitive and selective detection of explosives such as five-membered-ring energetic heterocyclic compounds in a few seconds with low detection limits through emission shift and/or turn-on. Remarkably, the cobalt-based MOF can selectively sense the powerful explosive 5-nitro-2,4-dihydro-3H-1,2,4-triazole-3-one with high sensitivity discernible by the naked eye (detection limit = 6.5 ng on a 1 cm(2) testing strip) and parts per billion-scale sensitivity by spectroscopy via pronounced fluorescence emission.

A Cooperative Copper Metal–Organic Framework‐Hydrogel System Improves Wound Healing in Diabetes

“…[13] They have been synthesized using a variety of organic ligands including ditopic, tritopic, tetratopic, hexatopic, octatopic, mixed, desymmetrized, metallo, and N-heterocyclic linkers. [14] MOFs have typically been used for gas adsorption and separation, [15] catalysis, [16] luminescence, [17] sensing, [18] proton conduction [19] and their properties could potentially be useful for biomedical applications. [20] Although potentially interesting for biomedical applications, MOFs tend to be not stable in physiological protein-containing solution.…”

Facile synthesis of size-controlled MIL-100(Fe) with excellent adsorption capacity for methylene blue

“…[3][4][5][6][7][8][9][10]. These porous materials are always composed of organic bridging ligands and metal ions to form three-dimensional extended networks with uniform pore diameter [11][12][13].…”

Zn2+‐Triggered Drug Release from Biocompatible Zirconium MOFs Equipped with Supramolecular Gates

“…On the other hand, metal-organic frameworks (MOFs) [13][14][15][16] are gaining momentum recently, in particular from drug delivery and storage, attributing to their enormous porosity, high surface area, good biodegradability and biocompatibility, versatile functionality, and a wide array of potentials in cell imaging. [17][18][19] UiO-66-NH 2 , a typical type of zirconium (Zr) based MOFs, contains linear 2-amino-1,4-benzenedicarboxylate (BDC-NH 2 ) ligands and Zr 6 O 4 (OH) 4 clusters as 12-connected nodes, and has garnered increasing attention due to the excellent stable structure and successful post-synthetic modifi cation (PSM).…”