Fei Ke

Thiol-functionalization of metal-organic framework by a facile coordination-based postsynthetic strategy and enhanced removal of Hg2+ from water

The presence of coordinatively unsaturated metal centers in metal-organic frameworks (MOFs) provides an accessible way to selectively functionalize MOFs through coordination bonds. In this work, we describe thiol-functionalization of MOFs by choosing a well known three-dimensional (3D) Cu-based MOF, i.e. [Cu(3)(BTC)(2)(H(2)O)(3)](n) (HKUST-1, BTC=benzene-1,3,5-tricarboxylate), by a facile coordination-based postsynthetic strategy, and demonstrate their application for removal of heavy metal ion from water. A series of [Cu(3)(BTC)(2)](n) samples stoichiometrically decorated with thiol groups has been prepared through coordination bonding of coordinatively unsaturated metal centers in HKUST-1 with -SH group in dithioglycol. The obtained thiol-functionalized samples were characterized by powder X-ray diffraction, scanning electron microscope, energy dispersive X-ray spectroscopy, infrared spectroscopy, and N(2) sorption-desorption isothermal. Significantly, the thiol-functionalized [Cu(3)(BTC)(2)](n) exhibited remarkably high adsorption affinity (K(d)=4.73 × 10(5)mL g(-1)) and high adsorption capacity (714.29 mg g(-1)) for Hg(2+) adsorption from water, while the unfunctionalized HKUST-1 showed no adsorption of Hg(2+) under the same condition.

Fe3O4@MOF core–shell magnetic microspheres with a designable metal–organic framework shell

A novel kind of porous microsphere with a magnetic core and a tunable metal–organic framework (MOF) shell has been successfully fabricated utilizing a versatile step-by-step assembly strategy. The structure, composition, and function of the microspheres can be judiciously tailored by choosing various metal ions and polyfunctional organic ligands or tuning the assembly processes. Our results provide a valuable methodology for rationally designing novel core–shell architectures and MOF-based porous magnetic platforms.

Facile fabrication of magnetic metal–organic framework nanocomposites for potential targeted drug delivery

In this paper, we describe a facile, efficient, and environmentally friendly fabrication of a novel type of magnetic porous metal–organic-framework (MOF)-based nanocomposites that can be potentially used for targeted drug delivery. The magnetic MOF nanocomposites were fabricated by incorporation of Fe3O4 nanorods with nanocrystals of Cu3(BTC)2 (HKUST-1), a three dimensional (3D) MOF with a 3D channel system. The as-synthesized materials exhibited both magnetic characteristics and high porosity, making them excellent candidates for targeted drug delivery systems. An anti-cancer drug acting as a selective cyclooxygenase-2 (COX-2) inhibitor for pancreatic cancer treatment, Nimesulide, was laden into pores of the nanocomposites. These MOF-based magnetic nanocomposites could adsorb up to 0.2 g of Nimesulide per gram of composite, and it took as long as 11 days to complete the drug release in physiological saline at 37 °C.

A novel magnetic recyclable photocatalyst based on a core–shell metal–organic framework Fe3O4@MIL-100(Fe) for the decolorization of methylene blue dye

We describe a novel type of magnetic recyclable Fe3O4@MIL-100(Fe) photocatalyst on the basis of a porous metal–organic framework (MOF) and its photocatalytic activities in the photodegradation of methylene blue (MB) dye. It was found that Fe3O4@MIL-100(Fe) exhibited photocatalytic activity for MB dye degradation under both UV-vis and visible light irradiation, and the MB decolorization over the Fe3O4@MIL-100(Fe) photocatalyst followed first-order kinetics. Moreover, it can be easily separated and recycled without significant loss of photocatalytic activity after being used many times. Therefore, compared to the conventional photocatalysts of TiO2 and C3N4 used in the photocatalytic degradation of dye, this magnetic core–shell photocatalyst is green, cheap and more suitable for large scale industrial applications.

Rapid synthesis of nanoscale terbium-based metal–organic frameworks by a combined ultrasound-vapour phase diffusion method for highly selective sensing of picric acid

A combined ultrasound-vapour phase diffusion technique was used for the rapid synthesis of a terbium-based metal–organic framework (MOF), [Tb(1,3,5-BTC)]n. Compared with conventional solvothermal and ultrasound-assisted methods, such a kind of combined ultrasound-vapour phase diffusion technique is highly sufficient for synthesizing nanoscale MOF crystals in remarkably high yields. Significantly, the as-prepared [Tb(1,3,5-BTC)]n nanocrystals exhibited highly selective sensing of picric acid (PA) without the interference of other nitroaromatic compounds such as nitrobenzene, 2-nitrotoluene, 4-nitrotoluene, 2,4-dinitrotoluene, and 2,6-dinitrotoluene. This makes them a potential candidate for developing novel luminescence sensors for the highly selective sensing of PA.

Facile fabrication of CdS-metal-organic framework nanocomposites with enhanced visible-light photocatalytic activity for organic transformation

Visible-light-initiated organic transformations have received much attention because of low cost, relative safety, and environmental friendliness. In this work, we report on a novel type of visible-light-driven photocatalysts, namely, porous nanocomposites of CdS-nanoparticle-decorated metal-organic frameworks (MOF), prepared by a simple solvothermal method in which porous MIL-100(Fe) served as the support and cadmium acetate (Cd(Ac)2) as the CdS precursor. When the selective oxidation of benzyl alcohol to benzaldehyde is used as the probe reaction, the results show that the combination of MIL-100(Fe) and CdS semiconductor can remarkably enhance the photocatalytic efficiency at room temperature, as compared to that of pure CdS. The enhanced photocatalytic performance can be attributed to the combined effects of enhanced light absorption, more efficient separation of photogenerated electron-hole pairs, and increased surface area of CdS due to the presence of MIL-100(Fe). This work demonstrates that MOF-based composite materials hold great promise for applications in the field of solar-energy conversion into chemical energy.

Controllable synthesis of metal–organic framework hollow nanospheres by a versatile step-by-step assembly strategy

Highly monodisperse metal–organic framework (MOF) hollow nanospheres have been rationally synthesized using monodisperse polystyrene (PS) nanoparticles as templates through a versatile step-by-step self-assembly strategy. The structure and composition of the hollow MOF-based nanostructures could be facilely tuned by choosing different framework building blocks (i.e. metal ions and polyfunctional organic ligands) and the hollow MOF shell thickness could also be easily controlled by tuning the number of growth cycles of the PS@MOF core–shell structures.