Ultrasonic-Assisted Synthesis of a Zn(II) Coordination Polymer in Aqueous Media and Its High-Performance Luminescent Sensing for 2,4,6-Trinitrophenol

Abstract

A novel Zn(II) coordination polymer based on 5-(3pyridyl)-1,3,4-oxadiazole-2-thiol (Hpzt), namely [Zn(pzt) 2 ] n or Zn-CP, was synthesized by two different synthetic methods. The bulk polycrystals and single crystals of Zn-CP were obtained by a conventional solvothermal method at 90 °C. Zn-CP exhibits a two-dimensional (2D) coordination network that contains the uncoordinated Lewis basic sites within each layer. Interestingly, a simple and environmentally friendly sonochemical synthesis of the Zn-CP in an aqueous media could be performed at room temperature. The optimal synthetic conditions were studied. The uniform microplates of Zn-CP were obtained within 30 min with the addition of pyridine, acting as a size modulator and a deprotonating reagent. The influence of the amount of the modulator and the sonication time on the crystal size was investigated. Moreover, a Zn-CP suspension in an ethanolic media has been used as a luminescence sensor for the detection of nitroaromatic compounds. It shows highly selective and sensitive sensing of 2,4,6-trinitrophenol (TNP) through a quenching (turn-off) process under UV light. Also, the Zn-CP microplates show higher dispersibility and a more stable suspension in comparison to those of bulk products, causing an increase of the luminescent sensing performance for TNP.

Highly selective and sensitive fluorescent zeolitic imidazole frameworks sensor for nitroaromatic explosive detection

“…Upon excitation at 365 nm, the ZnQ@ZIF-8 in ethanolic solution has shown an emission maximum at 510 nm which is attributed to a π* to n or a π* to π transition [30]. ZnQ encapsulation process greatly enhances the fluorescence emission spectrum of ZIF-8.…”

Coordination Polymers as a Functional Material for the Selective Molecular Recognition of Nitroaromatics and ipso‐Hydroxylation of Arylboronic Acids

“…[59] Usually, the conduction band of a CP is higher in energy than the valence band of a nitroaromatic analyte, which makes easy electron transfer from electron-rich CP to the electron-deficient NAC in their excited state, thus, assisting in the quenching process. [60,61] To corroborate the electron transfer mechanism, HOMO-LUMO energies of all the investigated nitroaromatics along with ligand L (Ref. 5) were calculated using density functional theory (DFT) at B3LYP level.…”

Metal-organic Framework-based Materials: Synthesis, Stability and Applications in Food Safety and Preservation

“…[167] Tunsrichon et al employed ultrasoundassisted method to synthesize a novel Zn 2+ coordination aggregate with 5-(3-pyridyl)-1,3,4-oxadiazole-2-thiol in an aqueous medium at room temperature within only 30 min, and utilized as a luminescence sensor for the detection of nitroaromatic compounds. [168] Briefly, microwave-and ultrasound-assisted MOF syntheses have shown great potential primarily caused by their quick synthesis rate, high yield, and controlled size and shape of the resulting particles.…”