Turn-on fluorescence detection of specific inorganic anions by Zr(Ⅳ)-MOF with amino-functional group

Inorganic anions such as phosphates and carbonates are essential in the natural system and it is important for the detec-tion of such species.In this work,the fluorescence sensing capacity of Zr(IV)framework with an amino-functional group,namely UiO-66-NH_(2),towards specific inorganic anions was investigated in aqueous media.The results revealed that the fluorescence emission intensity of UiO-66-NH2 could be strongly enhanced by phosphate and carbonate anions including HPO_(4)^(2-),H_(2)PO_(4)^(-),PO_(4)^(3-),P_(2)O_(7)^(4-),HCO_(3)^(-)and CO_(3)^(2-),implying its sensing capacity towards phosphate and carbonate anions.Furthermore,fluorescence titration experiments exhibit that the emission intensity enhancement ratio depends linearly on the concentration of anions,suggesting the possibility of quantitative detection of these anions.Further studies suggest that the sensing of UiO-66-NH,towards HPO_(4)^(2-)/PO_(4)^(3-)/P_(2)O_(4)^(-)/HCO_(3)^(-)/CO_(2)-could be ascribed to the collapse of the framework,while that for H_(2)PO_(4)-could be attributed to the adsorption of H,PO4-by UiO-66-NH2 with hydrogen bonding interactions between H,PO4-and the amino group of UiO-66-NH_(2) supported by the different fluorescence response of UiO-66 and UiO-66-NH,towards the anions.

Influence of temperature on metal-organic frameworks

Reaction temperature is one of the key parameters in the synthesis of metal-organic frameworks （MOFs）. Though there is no convergence with regard to the various experimental parameters, reaction temperature has been found to have remarkable influence on the formation and structure of MOFs, especially toward the control of topology and dimensionality of the MOF structures. Theoretically, the reaction temperature affects directly the reaction energy barrier in reaction thermodynamics and the reaction rate in the reaction kinetics. This review aims to show the influence of reaction temperature on crystal growth/assembly, structural modulation and transformation of MOFs, and to provide primary information and insights into the design and assernblv of desired MOFs.

Room temperature solution-phase synthesis of flower-like nanostructures of [Ni_3(BTC)_2·12H_2O] and their conversion to porous NiO

Hierarchical flower-like architectures of[Ni_3（BTC）_2·12H_2O]（BTC^3=benzene-1,3,5-tricarboxylate） were successfully prepared by a simple solution-phase method under mild conditions without any template or surfactant.Phase-pure porous NiO nanocrystals were obtained by annealing the Ni-BTC complex without significant alteration in morphology.The product was characterized by X-ray diffraction techniques,field-emission scanning electron microscopy（FESEM）.transmission electron microscopy（TEM） and high-resolution TEM（HRTEM）.The catalytic effect of the NiO product was investigated on the thermal decomposition of ammonium perchlorate（AP） and it was found that the annealed NiO product has higher catalytic activity than the commercial NiO.

Shape-controlled synthesis and photocatalytic activity of In_2O_3 nanostructures derived from coordination polymer precursors

In（BTC）（phen）（H_2O）nanocrystals with controllable morphology and size were successfully obtained by solvothermal method.Hierarchical straw-sheaf-like architectures,nanorods and elongated hexagons have been synthesized by varying the volume ratio of DMF：H_2O：C_2H_5OH.Phase-pure In_2O_3nanocrystals were obtained by the calcination of the precursors without significant alteration of the morphology.The products were characterized by PXRD,SEM,TEM,TGA,IR and gas adsorption measurements.The photocatalytic effect was investigated for the In_2O_3 nanocrystals with different morphology on the degradation of rhodamine B（Rh B）and it was found that the nanorods exhibited the best photocatalytic activity,which shows the degradation efficiency of 94%for 8 h.The results showed that the photocatalytic activity increased with the increase of BET surface area and pore volume.

Metal complex with terpyrindine derivative ligand as highly selective colorimetric sensor for iron(Ⅲ)

A new metal complex [MnL2]（NO3）2.CH3CN （1） was synthesized by reaction of 4＇-4-（],2,4-triazol-]-yl）- phenyl-2,2＇：6＇,2＂-terpyridine （L） with manganese nitrate. The structure of the complex was determined by X-ray crystallography. The results of UV-vis studies showed that the complex exhibits colorimetric sensing ability for Fe3~, which can be observed by naked eye.

Selective annulation of benzamides with internal alkynes catalyzed by an electron-deficient rhodium catalyst

An electron-deficient[CpERhCl2]2 catalyzed annulation of N-pentafluorophenylbenzamides with internal alkynes was successfully established under mild reaction conditions,with the assistance of Lewis acid silver salt.Particularly,electron-deficient benzamide substrates were smoothly transformed into the desired products in this catalytic system.The catalytic system showed a broad tolerance for different substituents on the aromatic rings or aryl,alkyl-substituted alkynes.