Metal–Organic Gel Leading to Customized Magnetic‑Coupling Engineering in Carbon Aerogels for Excellent Radar Stealth and Thermal Insulation Performances

Metal–organic gel(MOG)derived composites are promising multi-functional materials due to their alterable composition,identifiable chemical homogeneity,tunable shape,and porous structure.Herein,stable metal–organic hydrogels are prepared by regulating the complexation effect,solution polarity and curing speed.Meanwhile,collagen peptide is used to facilitate the fabrication of a porous aerogel with excellent physical properties as well as the homogeneous dispersion of magnetic particles during calcination.Subsequently,two kinds of heterometallic magnetic coupling systems are obtained through the application of Kirkendall effect.FeCo/nitrogen-doped carbon(NC)aerogel demonstrates an ultra-strong microwave absorption of−85 dB at an ultra-low loading of 5%.After reducing the time taken by atom shifting,a FeCo/Fe3O4/NC aerogel containing virus-shaped particles is obtained,which achieves an ultra-broad absorption of 7.44 GHz at an ultra-thin thickness of 1.59 mm due to the coupling effect offered by dual-soft-magnetic particles.Furthermore,both aerogels show excellent thermal insulation property,and their outstanding radar stealth performances in J-20 aircraft are confirmed by computer simulation technology.The formation mechanism of MOG is also discussed along with the thermal insulation and electromagnetic wave absorption mechanism of the aerogels,which will enable the development and application of novel and lightweight stealth coatings.

Metal-organic framework IRMOFs coated with a temperaturesensitive gel delivering norcantharidin to treat liver cancer

BACKGROUND Norcantharidin(NCTD)is suitable for the treatment of primary liver cancer,especially early and middle primary liver cancer.This compound can reduce tumors and improve immune function.However,the side effects of NCTD have limited its application.There is a marked need to reduce the side effects and increase the efficacy of NCTD.AIM To develop a nanomaterial carrier,NCTD-loaded metal-organic framework IRMOF-3 coated with a temperature-sensitive gel(NCTD-IRMOF-3-Gel),aiming to improve the anticancer activity of NCTD and reduce the drug dose.METHODS NCTD-IRMOF-3-Gel was obtained by a coordination reaction.The apparent characteristics and in vitro release of NCTD-IRMOF-3-Gel were investigated.Cell cytotoxicity assays,flow cytometry,and apoptosis experiments in mouse hepatoma(Hepa1-6)cells were used to determine the anti-liver cancer activity of NCTD-IRMOF-3-Gel in in vitro models.RESULTS The particle size of NCTD-IRMOF-3-Gel was 50-100 nm,and the particle size distribution was uniform.The release curve showed that NCTD-IRMOF-3-Gel had an obvious sustained-release effect.The cytotoxicity assays showed that the free drug NCTD and NCTD-IRMOF-3-Gel treatments markedly inhibited Hepa1-6 cell proliferation,and the inhibition rate increased with increasing drug concentration.By flow cytometry,NCTD-IRMOF-3-Gel was observed to block the Hepa1-6 cell cycle in the S and G2/M phases,and the thermosensitive gel nanoparticles may inhibit cell proliferation by inducing cell cycle arrest.Apoptosis experiments showed that NCTD-IRMOF-3-Gel induced the apoptosis of Hepa1-6 cells.CONCLUSION Our results indicated that the NCTD-IRMOF-3-Gel may be beneficial for liver cancer disease treatment.

Polyoxometalate-Based Porous Metal-Organic Gel for High-Efficiency Ultrasound-Assisted Oxidative Desulfurization of Model Fuel

A novel heterogeneous catalyst for ultrasound-assisted oxidative desulfurization(UAODS)was designed and synthesized by confining polyoxometalates(POMs)clusters within porous metal-organic gel.The catalyst microstructures were characterized by XRD,SEM-EDX,FT-IR,N_(2)adsorption-desorption,and XPS.Effects of POM loading,catalyst dosage,and ultrasonic power were also investigated.Results indicate that 60%-PMA@MOX(Al)exhibits optimal catalytic activity,with a sulfur removal rate of 98.61%and excellent reusability.Moreover,a kinetic study of different desulfurization approaches demonstrates that the unique thermal and cavitation effects of ultrasound can effectively improve the efficiency of oxidative desulfurization.

A gel polymer electrolyte with IL@UiO-66-NH_(2) as fillers for high-performance all-solid-state lithium metal batteries

All solid-state electrolytes have the advantages of good mechanical and thermal properties for safer energy storage,but their energy density has been limited by low ionic conductivity and large interfacial resistance caused by the poor Li~+transport kinetics due to the solid-solid contacts between the electrodes and the solid-state electrolytes.Herein,a novel gel polymer electrolyte(UPP-5)composed of ionic liquid incorporated metal-organic frameworks nanoparticles(IL@MOFs)is designed,it exhibits satisfying electrochemical performances,consisting of an excellent electrochemical stability window(5.5 V)and an improved Li^(+)transference number of 0.52.Moreover,the Li/UPP-5/LiFePO_(4) full cells present an ultra-stable cycling performance at 0.2C for over 100 cycles almost without any decay in capacities.This study might provide new insight to create an effective Li^(+)conductive network for the development of all-solid-state lithium-ion batteries.

Metal-Organic Gels Based on Carboxyl-Functionalized Benzimidazole and Their Stimuli Responsivenesses

Three multi-responsiveness supramolecular metal-organic gels(MOGs)have been prepared upon Ba(OAc)_(2),CdSO_(4)•8H_(2)O and Pb(NO_(3))_(2) with a simple ligand(G17)based on a carboxyl-functionalized benzimidazole derivative in alcoholic-water solutions.The MOGs display the formation of well-developed nanofibrillar networks composed of intertwined fibers which provide stability to gels structures through coordination,hydrogen bonding and π-π interactions characterized by using field emission scanning electron microscopy(FESEM),the fourier transform infrared(FT-IR)spectroscopy and powder X-ray diffraction(XRD)techniques.MOG-1 shows good stimuli responsiveness toward the changes in K_(2)CrO_(4),both MOG-2 and MOG-3 do good job toward the changes in Na_(2)S.Moreover,because these MOGs were formed easily by gelator with some heavy metal ion,such as Cd(Ⅱ)and Pb(Ⅱ),it might provide the basis for heavy metal ion capture and removal.

新型金属有机凝胶及其复合物的制备

金属-有机凝胶(Metal-organic gels MOG)通常是用有机溶液制备的,因其独特的性质引起了人们的广泛关注。近年来,金属有机凝胶作为一类新型多孔材料的出现,由于其较大的比表面积、高孔隙率、丰富的孔道结构和功能基团等特点,在水处理、医疗、储存、环境修复和催化等方面具有潜在的应用前景。MOG材料是制备其他复合金属有机凝胶的前提,与其他复合材料相比,MOG具有优异的性能,因此合成了一种新型的金属有机凝胶(MOGS)。本综述旨在简要介绍金属有机凝胶及其复合物Zr-MOG、Al-MOG、Fe-MOG的最常用制造方法。从可持续发展的角度出发,为吸附水中污染物的有效利用提供了一条可持续发展的途径。最后,还总结了MOG及其复合物开发相关的挑战、未来趋势和前景。

Mild metal-organic-gel route for synthesis of stable sub-5-nm metal-organic framework nanocrystals

Nanoscale metal-organic frameworks （NMOFs） have attracted increased attention in recent years for miniaturized and/or biological applications.However,the synthesis of ultrasmall NMOFs with good stability is a great challenge.In this study,sub-5-nm nano-HKUST-1 was prepared for the first time via a mild metalorganic gel route without surfactants or capping agents.Controlling the gelation process via anion-ligand self-assembly is the key to the formation of NMOFs.The Tyndall effect,zeta potential,and liquid adsorption indicated strong stability of the obtained nano-HKUST-1,even in water.Adsorption experiments were performed using different dyes （crystal violet and methylene blue） to demonstrate the size-dependent adsorption thermodynamics and kinetics of this famous MOF.The results of this study provide new insights regarding the synthesis of NMOFs and their efficient applications.

Multi-stimuli responsive metal-organic gel of benzimidazol-based ligands with lead nitrate and their use in removal of dyes from waste-water

A novel smart metal-organic gel（MOG） formed from biscarboxyl-functionalized benzimidazole derivative（D11） in the presence of lead nitrate has been investigated.The critical gel concentration for the formation of MOG was just 0.36 wt%,which exhibits a super gelation capability of D11.The coordination of the metal to the ligand D11 was found to play a vital role in the construction of the supramolecular MOG.Microstructures determined by SEM observation demonstrated that the MOG was formed by intertwined fibrils.Interestingly,the MOG exhibits pH-induced,thermo-induced,and chemical-induced reversible gel-sol transition.Meanwhile,this supramolecular MOG shows desirable absorption ability of methyl orange dye molecules in aqueous solution.

Coordination-Driven Terpyridyl Phosphine Pd(Ⅱ) Gels

Incorporation of phosphine-Pd catalytic centers in gel network is an important strategy to develop highly active catalysts.In this contribution we show that catalytically active phosphine-Pd(II)gels can be readily obtained via re-action of rigid bridging terpyridyl phosphines and Pd(II).The terpyridyl phosphines,Py2P2 and Py2P,contain one 4,2':6',4"-terpyridyl group and two/one diphenylphosphino groups.Reactions of Py2P2/Py2P and Pd(II)in CHCl_(3)-MeOH afforded the corresponding phosphine-Pd(II)gels at room temperature or at elevated temperature(40℃).The gelation is driven by formation of metal-organic coordination.Mild heating is important in triggering the formation of Py2P-Pd(II)gel.The gels have a coherent,rigid spongy porous network of continuous nanome-ter-sized particles.The phosphine-Pd(II)gels showed high activity in the Suzuki-Miyaura reactions of aryl bro-mides under ambient conditions and could be recycled and reused.