Jun-Cheng Jin

Luminescent sensing and photocatalytic degradation properties of an uncommon (4,5,5)-connected 3D MOF based on 3,5-di(3′,5′-dicarboxylphenyl)benzoic acid

An uncommon microporous metal–organic framework (MOF), {[Zn5(L)2(DMF)2(μ3-H2O)]·2DMF} (1), was successfully constructed using a less exploited symmetrical pentacarboxylate ligand, 3,5-di(3′,5′-dicarboxylphenyl)benzoic acid (H5L). The MOF 1 features a trinodal (4,5,5)-connected topology having a Schlafli symbol of (42·63·8)(45·65)2(46·64) and is stable in air as well as in acidic/basic aqueous media at room temperature. The MOF 1 behaves as a luminescent sensor for the highly selective and sensitive detection of Fe3+, Fe2+, Cu2+ and Ag+ ions and o-nitrophenol (MNP), p-nitrophenol (PNP), 2,4-dinitrophenol (DNP), 2,4,6-trinitrophenol (TNP) and 4-nitrotoluene (4-NT). Furthermore, the photocatalytic properties of 1 for the degradation of Methyl violet (MV) and Rhodamine B (RhB) have been explored. The possible quenching of the emissions of 1 in the presence of nitroaromatics has been addressed by theoretical calculations and the photocatalytic activity of 1 against organic dyes has been addressed using density of states (DOS) calculations.

A 3D luminescent Zn(II) MOF for the detection of high explosives and the degradation of organic dyes: an experimental and computational study

A new metal–organic framework, formulated as {[Zn2(L)(DMF)3]·2DMF·2H2O} (1), has been synthesized using a symmetrical rigid carboxylate ligand terphenyl-3,3′′,5,5′′-tetracarboxylic acid (H4L). Single-crystal X-ray diffraction analysis shows that 1 possesses a 3D uninodal 4-c lonsdaleite (lon) topology based on binuclear Zn clusters. 1 behaves as a fluorescent chemosensor for highly selective and sensitive detection of Fe3+/Fe2+ ions, 2,4-dinitrophenol (2,4-DNP), p-nitrophenol (PNP) and 2,4,6-trinitrophenol (TNP). Furthermore, the photocatalytic properties of 1 for degradation of methyl violet (MV) and Rhodamine B (RhB) have been explored. The possible emission quenching of 1 in the presence of aromatic compounds has been addressed by theoretical calculations and the photocatalytic activity of 1 against organic dyes has been addressed using density of states (DOS) calculations.

A new Zn(II) metal–organic framework having 3D CdSO4 topology as luminescent sensor and photocatalyst for degradation of organic dyes

A new Zn(II) metal–organic framework, formulated as {[Zn(L)]·2.7 DMF} (1), was synthesized using a multidentate ligand 1,4-bis(triazol-1-yl)terephthalic acid (H2L). The MOF 1 adopts 3D uninodal 4-c CdSO4 topology and behaves as a luminescent chemosensor for highly selective and sensitive detection of Fe3+ and nitro-aromatics, particularly 2,4,6-trinitrophenol (TNP). In addition, the thermal stability, UV/Vis diffuse-reflection spectra and photocatalytic behaviors of 1 against organic dyes have also been investigated. The possible mechanism associated with the alleviation in the emission intensity of 1 in the presence of nitro-aromatic compounds were addressed by theoretical calculations. In addition, the photocatalytic activity of 1 against organic dyes was addressed using density of states (DOS) calculations.

Combined experimental and theoretical insight into the drug delivery of nanoporous metal–organic frameworks

Two isostructural nanoporous MOFs with [Zn3(μ3-O)(BTC)2(H3O)]n (NTU-Z11) and {[Zn3(μ3-O)(BTC)2(DMF)]·2NH2(CH3)2·4H2O}n (GDMU) (BTC = 1,3,5-benzenetricarboxylate) have been used as drug carriers of 5-fluorouracil (5-FU). The incorporation of 5-FU into the desolvated NTU-Z11 and GDMU was around 0.38 g g−1 and 0.22 g g−1, respectively. NTU-Z11 presents pH-triggered controlled drug release properties in pH 6.0, 7.4 and 9.18 and water media. In addition, we performed GCMC simulations to investigate the loading of 5-FU into NTU-Z11 and GDMU at the molecular level. The results from simulations reproduce the experimental trend with respect to the drug loading capacity of each material. A comparison between the calculated drug loading values and some molecular level properties indicates the existence of a relationship between the void space of the material and the drug loading capacity.

A novel turn-on fluorescent sensor for highly selective detection of Al(III) in an aqueous solution based on simple electrochemically synthesized carbon dots

In this study, a simple and sensitive turn on fluorescent sensor for the detection of Al3+ ion in an aqueous solution was developed based on carbon dots (C-dots) obtained via one-step electrolysis of graphite in sodium hydroxide aqueous solution. The as-prepared C-dots exhibit excellent photoluminescence and up-conversion photoluminescence properties and have an average size of 5.0 nm. The as-prepared C-dots showed a light green luminescence emission under 365 nm ultraviolet excitation and could be used as a novel label-free turn on fluorescent probe for the selective detection of Al3+; this is quite different from the case of usual quenching effects of metal ions on fluorescent C-dots. The fluorescence enhancement effect of Al3+ ion on the as-prepared C-dots could be attributed to the chelation-enhanced fluorescence (CHEF) mechanism. Abundant oxygen functional groups on the surface of C-dots have chelation interaction with Al3+ and increase the rigidity of the C-dots, leading to fluorescence enhancement. Moreover, the as-prepared C-dots are highly selective for Al3+ over other metal ions, with a detection limit of 0.05 μM, and the linear relationship between fluorescence intensity and concentration of Al3+ is in the range of 0.1–7.2 μM. In addition, the as-prepared novel fluorescent probe was successfully applied for the direct analysis of Al3+ in a real environmental water sample.

Ferromagnetic Behavior of an Uncommon Trinuclearcopper(II) Coordination Polymer Based on Tartarate and 1,2-bis(4-Pyridyl)ethane Linker

A new Cu(II) based metal-organic framework (MOF) having formula [Cu3(H2Tar)(Tar)-(H2O)(Bpa)] · 3H2O (I) (H4Tar = tartaric acid, Bpa = 1,2-bis(4-pyridyl)ethane) has been characterized by elemental analysis, FT-IR spectra, thermal analysis, and single-crystal X-ray diffraction (CIF file CCDC no. 1575136). In I, the Cu(II) center are connected by four symmetry-related tartrate ligands into a 2D layer encapsulating trinuclear cluster, which are further bridged by Bpa molecules into a 3D framework. Complex I exhibits strong ferromagnetic behavior between metal centers.

Properties, Preparation and Applications of Low Dimensional Transition Metal Dichalcogenides

Low-dimensional layered transition metal dichalcogenides (TMDs) have recently emerged as an important fundamental research material because of their unique structural, physical and chemical properties. These novel properties make these TMDs a suitable candidate in numerous potential applications. In this review, we briefly summarize the properties of low-dimensional TMDs, and then focus on the various methods used in their preparation. The use of TMDs in electronic devices, optoelectronic devices, electrocatalysts, biosystems, and hydrogen storage is also explored. The cutting-edge future development probabilities of these materials and numerous research challenges are also outlined in this review.

An Unusual 3D Interdigitated Network Structure of Bridging Coligands With Appended Hydrogen Sites

A new coordination compound, namely, [(H3DDA)(H4DDA)0.5 (H2bpe)0.5(H2O)] (1) (H4DDA = 4,4′-diazenediyldiphthalic acid and bpe = -1,2-bis(4-pyridyl)ethene), has been synthesized and characterized by IR and single-crystal X-ray diffraction. The adduct 1 exhibits a new 1D+2D→3D interdigitated architecture that is obtained from the self-assembly of the 2D hydrogen bonding sheet network directed by H4DDA, free water molecule, and H3DDA. Further, each sheet is interdigitated by the 1D chain formed by N-protonated bpe and H3DDA.