A Zn(II)-Metal-Organic Framework Based on 4-(4-Carboxy phenoxy) Phthalate Acid as Luminescent Sensor for Detection of Acetone and Tetracycline

As hazardous environmental pollutants, residual tetracycline (TC) and acetone are harmful to the ecosystem. Therefore, it is necessary to detect the presence of these pollutants in the environment. In this work, using Zn (II) salt, 4-(4-carboxy phenoxy) phthalic acid (H₃L), and 3,5-bis(1-imidazolyl) pyridine (BMP), a new metal-organic framework (Zn-MOF) known as [Zn₃(BMP)₂L₂(H₂O)₄]·2H₂O was synthesized using a one-pot hydrothermal method. The Zn-MOF has a three-dimensional framework based on the [Zn1N₂O₂] and [Zn2N₂O₄] nodes linked by a tridentate bridge BMP ligand and an L ligand with the μ₁:η¹η⁰/μ₁:η¹η⁰/μ₀:η⁰η⁰ coordination mode. There were two kinds of left- and right-handed helix chains, Zn1-BMP and Zn1-BMP-Zn1-L. The complex was stable in aqueous solutions with pH values of 4-10. The Zn-MOF exhibited a strong emission band centered at 385 nm owing to the π*→π electron transition of the ligand. It showed high luminescence in some common organic solvents as well as in the aqueous solutions of pH 4-10. Interestingly, TC and acetone effectively quenched the luminescence of the Zn-MOF in aqueous solution and enabled the Zn-MOF to be used as a sensor to detect TC and acetone. The detection limits of TC and acetone were observed to be 3.34 µM and 0.1597%, respectively. Even in acidic (pH = 4) and alkaline (pH = 10) conditions, the Zn-MOF showed a stable luminescence sensing capability to detect TC. Luminescence sensing of the Zn-MOF for TC in urine and aquaculture wastewater systems was not affected by the interfering agent. Furthermore, the mechanism of sensing TC was investigated in this study. Fluorescence resonance energy transfer and photoinduced electron transfer were found to be the possible quenching mechanisms via UV-Vis absorption spectra/the excitation spectra measurements and DFT calculations.

Two New 3D Supramolecular Complexes: Photocatalytic Properties and Treatment Activity for Gastric Cancer

Two new coordination polymers, [Cu₂(5-MeO-Hip)₄(py)₄]_n (1) and [Co(5-EtO-ip)(4,4'-bipy)]_n·n(MeOH) (2) (5-MeO-H₂ip is 5-methoxyisophthalic acid, 5-EtO-H₂ip is 5-ethoxyisophthalic acid, py is pyridine, and 4,4'-bipy is 4,4'-bipyridine), were created via solvothermal self-assembly. The thermal steadiness and photocatalytic functions of 1 and 2 were detected, and their application values in gastric cancer and the related mechanism were discussed. CCK-8 assay was used to determine the inhibitory activity toward gastric cancer cells' viability, and real-time RT-PCR was employed to examine the gastric cancer cells' Notch signaling pathway activity.

Crystal structure of catena-poly[bis(µ2-3,5-bis(1-imidazolyl)pyridine-κ2 N:N′)-(µ2-3-nitrophthalato-k3 O,O′:O″)cadmium(II)] dihydrate, C30H25N11O8Cd

C30H25N11O8Cd, orthorhombic, Pnma (no. 62), a = 17.9344(3) Å, b = 18.2722(3) Å, c = 9.5619(2) Å, V = 3133.44(10) Å3, Z = 4, R gt (F) = 0.0345, wR ref (F 2) = 0.0707, T = 293.28(10) K.

Four structural diversity MOF-photocatalysts readily prepared for the degradation of the methyl violet dye under UV-visible light

The photocatalytic results demonstrated that all of them displayed efficient photocatalytic performances towards the degradation of methyl violet. The mechanism has been proposed.

Syntheses of a series of lanthanide metal–organic frameworks for efficient UV-light-driven dye degradation: experiment and simulation

Three Ln-MOFs show unique 3,8-connected 3D networks and have been used as photocatalysts for the degradation of organic dye methyl violet under UV light.

Efficient photocatalytic degradation of methyl violet using two new 3D MOFs directed by different carboxylate spacers

Both the MOFs proved to be good candidates for the photocatalytic degradation of methyl violet. The mechanism of these photocatalytic degradations is discussed.

New Cd(ii) coordination polymers bearing Y-shaped tricarboxylate ligands as photocatalysts for dye degradation

Two Cd(ii) coordination polymers derived from a Y-shaped tricarboxylate ligand were synthesized and their photocatalytic properties against decomposition of methylene blue were investigated experimentally and computationally.

Structures and photocatalytic properties of two new Zn(ii) coordination polymers based on semi-rigid V-shaped multicarboxylate ligands

Two new metal-organic coordination polymers (CPs), aqua-2,2'-bipyridine-5-(4'-carboxylphenoxy)isophthalatezinc(ii) polymer [Zn(HL)(2,2'-bipy)(H₂O)] _n (1) and tris-4,4'-bipyridine-bis-5-(4'-carboxylphenoxy)isophthalatetrizinc(ii) polymer [Zn₃(L)2(4,4'-bipy)₃] _n (2) (H₃L = 5-(4'-carboxylphenoxy)isophthalic acid, 4,4'-bipy = 4,4'-bipyridine and 2,2'-bipy = 2,2'-bipyridine), were obtained under hydrothermal conditions and characterized by microanalysis, FTIR spectroscopy and single crystal X-ray diffraction. The single crystal X-ray diffraction indicated that in both the CPs the coordination networks exhibited varied topologies and coordination modes around the Zn(ii) centers. CP 1 exhibits a one-dimensional (1D) chain structure, which further forms a 3D supramolecular architecture via intermolecular π⋯π and hydrogen bonding interactions, while 2 possesses a 3D framework generated from a 2D layered motif comprising zinc and tripodal carboxylate subunits pillared by 4,4'-bpy ligands. Apart from the structural investigation, the photocatalytic performances of both the coordination polymers to photodecompose an aqueous solution of methyl violet (MV) were examined. The results indicated that both the CPs displayed the potential to photodecompose aromatic dyes and in particular 2 showed good photocatalytic activity for dye degradation under light irradiation. The photocatalytic mechanism through which these CPs executed degradation of dyes has been explained with the assistance of band gap calculations using density of states (DOS) and its decomposed partial DOS calculations.

Synthesis, structure and photocatalytic properties of coordination polymers based on pyrazole carboxylic acid ligands

The photocatalytic activities of two novel different 2-D coordination polymers constructed from 5-hydroxy-1H-pyrazole-3-carboxylic acid ligand have been explored.

Formamide-assisted one-step synthesis of BiOCOOH and Bi/BiOCOOH micro-/nanostructures with tunable morphologies and composition and their photocatalytic activities

A series of BiOCOOH and Bi/BiOCOOH heterojunction photocatalysts have been facilely synthesized by a one-step reaction with the assistance of formamide.