Rational synthesis of a pyridyl-imidazoquinazoline based multifunctional 3D Zn(ii)-MOF: structure, luminescence, selective and sensitive detection of Al3+ and TNP, and its semiconducting device application. Issue 36 (26th August 2022)

• Record Type: Journal Article
• Authors: Bairy, Gurupada; Dey, Arka; Dutta, Basudeb; Maity, Suvendu; Sinha, Chittaranjan
• Is Part Of: Dalton transactions. Volume 51:Issue 36(2022)
• Page Start: 13749
• Page End: 13761
• Publication Date: 2022-08-26
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d2dt01790c
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : A novel luminescent multifunctional 3D Zn(ii )-pyridylimidazoquinazoline MOF was synthesised and used as a selective sensor for the detection of Al 3+ and trinitrophenol and to fabricate a Schottky diode with improved photo-conductivity. Abstract : In the age of sustainable development, the exploration of multifunctional materials is of high priority due to their economic benefits and environmental suitability. A stable luminescent coordination polymer, [Zn2 (tdc)4 (pdiq)3 ] (1 ), (pdiq = pyridyl-imidazoquinazoline; H2 tdc = 2, 5-thiophenedicarboxylic acid) has been prepared and structurally confirmed by single-crystal X-ray diffraction analysis. The 3D framework consists of a distorted octahedral geometry with a ZnO4 N2 coordination sphere where four carboxylato-O donations come from two tdc 2− as bridging ligands and two pyridyl-Ns come from two pdiq. The π⋯π interactions between the imidazolium and phenyl groups bestow robustness on the architecture. The compound is chemically stable to water, shows tolerance to acid/base aqueous solutions (pH = 2–12), and is stable to the impact of organic solvents. The high dispersibility of Zn-MOF (1 ) in acetonitrile may enhance the fluorescence intensity compared to that in water, which prompted fluorescence measurements in the former solvent and it is used for the efficient and selective turn-off ratiometric sensing of Al 3+ ions (LOD, 1.39 × 10 −7 M). In addition, the fluorescence emission of 1 is instantly quenched by trinitrophenol (TNP) and the LOD is 1.54 × 10 −7 M. The Tauc's plot is used to measure the semiconducting band gap (3.33 eV) and the electrical conductivity is significantly increased upon illumination ( Λ : 1.14 × 10 −3 S m −1 (dark), 5.35 × 10 −3 S m −1 (light)) and the energy barrier declines marginally (FB: 0.57 (dark), 0.49 (light)). Transit time ( τ ) and diffusion length ( L D ) at the quasi-Fermi level were analyzed to offer information on the charge transport mechanism of the compound. The better performance on photo-irradiation signifies the enhanced charge transfer kinetics of a Zn-MOF coated thin-film device (TFD 1), which encourages its application in semiconductor devices.