Layer-structured lanthanide coordination polymers constructed from 3,5-bis(3,5-dicarboxylphenyl)-pyridine ligand as fluorescent probe for nitroaromatics and metal ions

S-Heptazine N-ligand based luminescent coordination materials: synthesis, structural and luminescent studies of lanthanide-cyamelurate networks

Various series of lanthanide metal-organic networks denoted Ln-Cy (Ln = La, Ce, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb), were synthesized under solvothermal conditions using potassium cyamelurate (K₃Cy) and lanthanide nitrate salts. All obtained materials were fully characterized, and their crystal structures were solved by single-crystal X-ray diffraction. Four types of coordination modes were elucidated for the Ln-Cy series with different Ln³⁺ coordination geometries. Structural studies were performed to compare the various coordination compounds of the Ln-Cy series. Moreover, the cyamelurate linkers of rich π-conjugated and uncoordinated Lewis basic sites were used as an absorbing chromophore to enhance the luminescence quantum efficiency, the band emission and the luminescence lifetime of the coordinated Ln metal centers. Solid-state UV-visible measurements combined with density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations were performed to further explore luminescent features of the Ln-Cy series and their origins.

Carbon dots-decorated hydroxyapatite nanowires–lanthanide metal–organic framework composites as fluorescent sensors for the detection of dopamine

A ratiometric composite fluorescent probe (HAPNWs-CDs-Tb/MOF) with hydroxyapatite carrier and the fluorescence ratio of carbon dots and lanthanide metal organic framework as the response signal was prepared for the detection of dopamine.

A novel 3D coordination polymer constructed by dual-ligand for highly sensitive detection of purine metabolite uric acid

Uric acid (UA), as the final product of purine metabolism, exists in urine and serum, which plays an important role in human metabolism, immunity and other functions. The sensitive, efficient, and rapid detection of UA has far-reaching significance in clinical diagnosis and disease prevention. Herein, a novel coordination polymer constructed by dual-ligand was successfully prepared, which exhibited excellent thermal and water stability. The polymer was interlaced by coordination bonds and hydrogen bonds to form an infinitely extended three-dimensional framework, which showed a rare and novel topological structure. The complex selectively recognized UA through significant fluorescence quenching response in the presence of various interferences. The excellent detection sensitivity (the limited detection of 1.2 μM), outstanding anti-interference ability and remarkable recyclability marked the complex to be a promising sensor material towards UA. In addition, the detection mechanism of UA by the complex was investigated in detail by combining density functional theory (DFT) and a variety of other analytical methods.

Synthesis, structure, photophysical properties, and energy transfer mechanism of an erbium–mercury compound

A hydrothermal reaction leads to the formation of a novel erbium–mercury compound [Er(IA)3(H3O)(H2O)] n(0.5 nHg2I6) (1) (HIA = isonicotinic acid). The compound has been characterized by single-crystal X-ray diffraction. It is characteristic of a one-dimensional chain-like structure and a two-dimensional supramolecular layer. A solid-state photoluminescence experiment reveals that this compound displays upconversion green photoluminescence. The photoluminescence emission peaks can be attributed to the 4 G11/2 → 4 I15/2, 4 F7/2 → 4 I15/2, and 2 H11/2 → 4 I15/2 of the Er3+ ions. The energy transfer mechanism is consistent with the energy-level diagrams of the erbium ions and isonicotinic acid ligand. This compound possesses Commission Internationale de I'Éclairage chromaticity coordinates of 0.1755 and 0.5213. A solid-state diffuse reflectance measurement reveals that this compound features a narrow optical band gap of 1.97 eV.

Conductive MOFs with Photophysical Properties: Applications and Thin-Film Fabrication

Metal-organic frameworks (MOFs) are a class of hybrid materials with many promising applications. In recent years, lots of investigations have been oriented toward applications of MOFs in electronic and photoelectronic devices. While many high-quality reviews have focused on synthesis and mechanisms of electrically conductive MOFs, few of them focus on their photophysical properties. Herein, we provide an in-depth review on photoconductive and photoluminescent properties of conductive MOFs together with their corresponding applications in solar cells, luminescent sensing, light emitting, and so forth. For integration of MOFs with practical devices, recent advances in fabrication of photoactive MOF thin films are also summarized.

Functional metal–organic frameworks as effective sensors of gases and volatile compounds

This review summarizes the recent advances of metal organic framework (MOF) based sensing of gases and volatile compounds.

Multiporous Terbium Phosphonate Coordination Polymer Microspheres as Fluorescent Probes for Trace Anthrax Biomarker Detection

Lanthanide coordination polymers have been recently regarded as attractive sensing materials because of their selectivity, high sensitivity, and rapid response ability. In this research, the multiporous terbium phosphonate coordination polymer microspheres (TbP-CPs) were prepared as a novel fluorescent probe, which showed a fluorescence turn-on response capability for the detection of the trace anthrax biomarker dipicolinate acid (DPA). The morphology and chemical composition of as-prepared TbP-CPs were characterized in detail. The TbP-CPs have the vegetable-flower-like structure and microporous surface. In addition, the as-prepared TbP-CPs not only possess the merits of convenience and simple preparation with high yield but also have the excellent characters as fluorescent probes, such as high stability, good selectivity, and rapid detection ability within 30 s. This proposed sensor could detect DPA with a linear relationship in concentrations ranging from 0 to 8.0 μM and a high detection sensitivity of 5.0 nM. Furthermore, the successful applications of DPA detection in urine and bovine serum were demonstrated. As a result, the recovery ranged from 93.93-101.6%, and the relative standard deviations (RSD) were less than 5%.

Near-infrared-emissive metal–organic frameworks

We describe the recent progress in near-infrared-emissive metal–organic frameworks, and especially highlight their appealing applications in bio-imaging, sensing and barcoding.