Highly-stable cobalt metal organic framework with sheet-like structure for ultra-efficient water oxidation at high current density

RhB-Embedded Mn-MOF with Cyclotriphosphazene Skeleton as Dual-Emission Sensor for Putrescine as well as Smart Fluorescent Response of Aromatic Diamines and Nitrophenol

Luminescent metal-organic framework composites with multiple luminescence emissions have been efficient sensing platforms. Herein, a fluorescent sensor (RhB@1-0.4) with dual-emission fluorescence properties was prepared by introducing rhodamine B (RhB) into the framework of complex 1, [Mn2.5(HCPCP)(H2O)4]·(CH3CN)0.5 [HCPCP = hexa-(4-carboxyl-phenoxy)-cyclotriphosphazene and CH3CN = acetonitrile), which is a novel crystalline two-dimensional (2D) coordinated organic framework material. It is a highly desirable material, realizing a ratiometric fluorescence response to putrescine with a high signal-to-noise ratio, and the detection limit can be as low as 6.8 μM. In addition, RhB@1-0.4 exhibited a better fluorescent sensing performance for aromatic diamines and nitrophenols compared with that of complex 1. It is a potential functionalized MOF material for the application of multichannel fluorescence sensing.

Design of five two-dimensional Co-metal-organic frameworks for oxygen evolution reaction and dye degradation properties

Two-dimensional (2D) metal-organic frameworks (MOFs) have been extensively investigated as oxygen evolution reaction (OER) materials because of their numerous advantages such as large specific surface areas, ultrathin thicknesses, well-defined active metal centers, and adjustable pore structures. Five Co-metal-organic frameworks, namely, [Co(L) (4.4′-bbidpe)H2O]n [YMUN 1 (YMUN for Youjiang Medical University for Nationalities)], {[Co2(L)2 (4.4′-bbibp)2]·[Co3(L) (4.4′-bbibp)]·DMAC}n (YMUN 2), [Co(L) (3,5-bip)]n (YMUN 3), [Co(L) (1,4-bimb)]n (YMUN 4), and [Co(L) (4.4′-bidpe)H2O]n (YMUN 5), were designed and fabricated from flexible dicarboxylic acid 1,3-bis(4′-carboxylphenoxy)benzene (H2L) and rigid/flexible imidazole ligands. Their frameworks consist of two-dimensional lamellar networks with a number of differences in their details. Their frameworks are discussed and compared, and their oxygen evolution reaction electrochemical activities and photocatalysis dye degradation properties are investigated.

The detection of multiple analytes by using visual colorimetric and fluorometric multimodal chemosensor based on the azo dye

In recent decades, researchers have conducted in-depth studies of the design and synthesis of colorimetric/fluorometric probes and the application of such probes to biological and practical samples. The multifunctional colorimetric and fluorescent azo benzene-based probe (4′-hydroxyl-2,4-diaminoazobenzene, MP) was designed to detect Al³⁺, Fe³⁺, Cu²⁺ and F¯. Based on the distinct redshift of the absorption band and a significant color change (yellow → purple), MP was utilized for both naked-eyed and quantitative detection of Al³⁺ and Fe³⁺ after formation of the 1:1 complex. Test paper coated with MP and used in conjunction with a cell phone was used for colorimetric detection of Al³⁺ and Fe³⁺ ions (20 μM–2.0 mM) in water samples through naked-eye and digital image colorimetry. The “MP-Fe³⁺” coordination shift that occurs in the presence of the competitive ligand F¯ was used in the colorimetric measurement of F¯ in toothpaste. In the presence of Cu²⁺ ion, the non-emissive MP has transformed into fluorescent benzotriazole product PMP (Φ = 0.53) through the bimolecular rate-limiting step, and the second-order rate constant k is calculated as 31 ± 2 M⁻¹ s⁻¹. MP exhibits a “turn-on” fluorescence response in the presence of Cu²⁺ that is greater than its response in the presence of competitive species such as Fe³⁺, Al³⁺, Co²⁺, Fe²⁺, Zn²⁺, Cd²⁺, Mg²⁺, Mn²⁺, Ni²⁺ and Ag⁺. MP was shown to have low toxicity to living HeLa cells and to present good imaging characteristics for tracking of Cu²⁺ in vivo.

Two Co(II) and Zn(II)-Related Coordination Polymers: The Diversity of Structure and Treatment Activity on Orthodontic Root Resorption Repair

Co(II)- and Zn(II)-related coordination polymers (CPs): [Co(OPBT)(GA)]n (1) and {[Zn2TTPA(GA)2] · 2H2O}n (2), where TTPA represents tris(4-(1H-1,2,4-triazol-1-yl)phenyl)amine) and OPBT represents 1.1′-(oxybis(1,4-phenylene))bis(1H-1,2,4-triazole), were prepared through mixed-ligand synthesis. The raw materials were flexible glutaric acid (H2GA) with Co(II)/Zn(II) nitrate salts, TTPA, and bi- and tritopic 1,2,4-disparate triazole derivatives. The application value of the CPs in orthodontic root resorption repair was evaluated, and their relevant mechanisms were explored. ELISA assay was used in determining the content of tumor necrosis factor-α released in the gingiva groove. Then, real time RT-PCR was utilized in assessing whether the nuclear factor kappa-B inflammatory activity was activated. Additionally, the CCK-8 method was used in investigating positive effects on osteoblast proliferation. Finally, the expression of the wnt protein in osteoblasts was detected with Western blotting assay.

An excellent multifunctional photocatalyst cooperated by polyoxometalate-viologen framework for CEES oxidation, Cr(VI) reduction and dyes decolorization under different light regimes

Photocatalytic detoxification of highly toxic agents is a promising approach to protect ecological environment and human health, and the key problem lies in the development of novel efficient photocatalysts. Herein,...

A layered Mn-based coordination polymer as an efficient heterogeneous catalyst for CO2 cycloaddition under mild conditions

A layered coordination polymer has been constructed by using a semi-rigid ligand, exhibiting a robust catalytic activity toward the cycloaddition of CO2 with epoxides.

Recent advances on bimetallic metal-organic frameworks (BMOFs): Syntheses, applications and challenges

Bimetallic metal-organic frameworks (MOFs) possess two different metal ions as nodes in their molecular frameworks. They are prepared by either using one-pot syntheses wherein different metals are mixed with suitable...

Efficient photodegradation of dyes by a new 3D Cd(II) MOF with rare fsh topology

Metal–organic frameworks (MOFs) can be regarded as 3D coordination polymers that adopt ordered porous structures and possess abundant active sites, which make them promising photocatalysts for the degradation of organic...

Impact of N-donor auxiliary ligands on two new Co(II)-based MOFs with N-heterocyclic ligands and magnetism study

Two new cobalt(II) MOFs, namely [Co2(L)2(4,4′-bipy)]n (1) and {[Co(L)(dib)0.5(H2O)2]·H2O}n (2) were obtained by the self-assembly of Co(NO3)2·6H2O with V-shaped 2,4-[6-(4-carboxyphenyl)pyrazin-2-yl]benzoic acid (H2L) in the presence of two bridging auxiliary N-donor...