Shengqun Su

A robust near infrared luminescent ytterbium metal-organic framework for sensing of small molecules

The first near-infrared luminescent ytterbium metal-organic framework has been realized for the highly selective and sensitive sensing of small molecules.

One-dimensional channel-structured Eu-MOF for sensing small organic molecules and Cu2+ ion

Two new lanthanide metal–organic frameworks Ln(FBPT)(H2O)(DMF) (FBPT = 2′-fluoro-biphenyl-3,4′,5-tricarboxylate, Ln = Eu and Tb) were prepared under solvothermal conditions. Single crystal X-ray diffraction analyses reveal that the two compounds are isostructurally related with the same one-dimensional channel structure on the basis of FBPT as an organic linker. Herein, the Eu(FBPT)(H2O)(DMF) (EuL) is selected as a representative sample for luminescent measurements. Study of the photoluminescence properties reveals that the EuL exhibits red emission, corresponding to the 5D0 → 7FJ (J = 1–4) transitions of the Eu3+ ion under UV light excitation. Most interestingly, when this compound was immersed in the different organic solvents and metal ion DMF solutions, it shows highly selective and sensitive sensing for small organic molecules and Cu2+ ions. In connection to this, a probable sensing mechanism was also discussed in this paper.

A ketone functionalized luminescent terbium metal–organic framework for sensing of small molecules

A ketone functionalized luminescent terbium metal-organic framework has been realized for the highly selective and sensitive sensing of aniline.

Porous Co3O4 microcubes: hydrothermal synthesis, catalytic and magnetic properties

Well-defined porous Co3O4 microcubes have been synthesized by a simple one-pot solvothermal method combined with subsequent calcination. The formation mechanism of the cube-like precursor was proposed based on the anisotropic intrinsic structure of CoCO3. Importantly, after thermal treatment, the cube-like morphology could be completely preserved. Moreover, the thermal decomposition of the corresponding precursor led to the formation of porous structure. The effects of calcination temperature on the catalytic properties of Co3O4 samples were investigated and the results demonstrated that 600 °C was superior among three samples with the highest catalytic properties. Additionally, as an antiferromagnetic material, the sample showed a certain degree of ferromagnetism under the external magnetic field.

Direct hydrothermal synthesis of single-crystalline triangular Fe3O4 nanoprisms

Single-crystalline Fe3O4 triangular nanoprisms (TNPs) were fabricated by a facile hydrothermal route in the presence of 1,3-propanediamine (PDA). It was found that the EG to PDA volume ratio played an important role in the formation of the TNP structures and greatly affected the morphology of the magnetites.

Interweaving of single-helical and equal double-helical chains with the same helical axis in a 3D metal–organic framework

A novel metal–organic framework with unprecedented interweaving of coaxial single-helical and equal double-helical chains of opposite chirality, which features a super-connective helix simultaneously tangling with eight helices, was reported.

Raisin-like rare earth doped gadolinium fluoride nanocrystals: microwave synthesis and magnetic and upconversion luminescent properties

Bifunctional lanthanide doped 3D raisin-like GdF3 nanocrystals were synthesized by a microwave method. The influences of synthesis parameters on the final morphology were investigated and the morphology can be tuned to snow-like microcrystals and nanocrystals. The as-prepared samples possess properties of multicolor upconversion (UC) photoluminescence (PL) and paramagnetism. To understand the magnetic mechanism, temperature dependence of zero-field cooling (ZFC) and field cooling (FC) magnetization of the raisin-like GdF3 nanocrystals were studied.

Five three/two-fold interpenetrating architectures from self-assembly of fluorene-2,7-dicarboxylic acid derivatives and d10 metals

Five new three/two-fold interpenetrated coordination polymers, namely, [Cd(mfda)(L1)] (1), [Cd(efda)(L1)] (2), [Zn2(mfda)2(L2)]·DMF·H2O (3), [Zn2(efda)2(L2)]·(DMF)0.25, (4) and [Cd2(mfda)2(L2)2]·DMF·H2O (5) (H2mfda = 9,9-dimethylfluorene-2,7-dicarboxylic acid, H2efda = 9,9-diethylfluorene-2,7-dicarboxylic acid, L1 = Methylene bis(3,5-dimethylpyrazole) and L2 = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene), have been synthesized under solvent-thermal conditions with mixed ligands. Compounds 1 and 2 are isostructural and possess two-dimensional (6, 3) layered structures containing two kinds of rings. Three equivalent (6, 3) net interpenetrate in a parallel fashion to form an unprecedented mat-like 2D sheet. Compounds 3 and 4 are almost identical in structure and display threefold interpenetrating α–Po net structures. Compound 5 displays a twofold interpenetrated 3D 6-connected net with α–Po topology. The luminescent properties of these compounds have been studied in the solid state at room temperature.

Hydrothermal synthesis and upconversion photoluminescence properties of lanthanide doped YF3 sub-microflowers

Yttrium fluoride sub-microflowers were synthesized by facile hydrothermal route without using any expensive or environmental unfriendly agents. The influences of various hydrothermal parameters on the final products were investigated. It was found that the concentration of NH3·H2O had a significant effect on the morphology change of YF3 sub-microcrystals. The growth mechanism of the as-obtained YF3 sub-microflowers was proposed. The multicolor upconversion (UC) photoluminescence (PL) was successfully realized in Yb3+/Tm3+, Yb3+/Ho3+ and Yb3+/Er3+ doped YF3 sub-microflowers when excited by 980 nm laser diode (LD). The pumping power dependence of the fluorescent intensity is investigated to understand the fundamental UC mechanism.

A series of POM/Ag-based hybrids: distinct forms and assembly of [AgxLy] complexes through combinational effects of POM and isomeric ligands

Five POM/Ag-based hybrids were obtained under hydrothermal conditions: (AgLa)2[Ag2La2(SiW12O40)] (1), [(AgLb)2-Ag2Lb2][(SiW12O40)] (2) Na2[AgLa(HLa)]2[Ag5La4(H2O)2][H(P2W18O62)2] ·21.6H2O (3), [Ag5Lb5][K2(OH)P2W18O62]·H2O (4) and [Ag2La2][HPW12O40]·7.5H2O (5) (La = 1,2-bis(imidazol-1-ylmethyl)benzene; Lb = 1,3-bis(imidazol-1-ylmethyl)benzene). It is likely that the forms and assembly of [AgxLy] complexes are crucial to the eventual structures, which are quite dependent on the POM and isomeric ligands in combination. Compound 1 shows a “S”-like chain structure with [(AgLa)2]n2n+ templates, while compound 2 features a unique 2D layer constructed by polypseudo-rotoxane motifs and infinite Ag chains. Compound 3 exhibits a 2D layer consisting of {Dawson-Ag5} double chain and [AgLa2] complexes. Compound 4 possesses a 3D poly-threading framework containing {POM-K} chains and interdigitated metal–organic layers. Compound 5 is a 1D chain, formed by Keggin anions and [Ag2La2] circles. Further, the luminescent and electrochemical properties of 1–5 are also investigated.