金属-有机骨架材料及其在催化反应中的应用

金属-有机骨架(metal-organic frameworks, MOFs)材料是由金属离子和有机配体通过自组装而成的具有多孔结构的特殊晶体材料。由于其种类的多样性、孔道的可调性和结构的易功能化,已在气体的吸附和分离、催化、磁学、生物医学等领域表现出了诱人的应用前景。本文介绍了MOFs材料的类型和常用的合成方法,综述了近年来MOFs材料在催化领域的应用,特别是以MOFs材料中骨架金属作为活性中心、骨架有机配体作为活性中心和负载催化活性组分的催化反应,并对MOFs材料的催化应用趋势做了展望,以期对MOFs材料的催化性能有比较全面的认识。     

磁性金属-有机骨架材料的合成及其应用

磁性金属-有机骨架(magnetic metal-organic frameworks,MMOFs)材料是近年来兴起的新型纳米功能材料,它由MOFs材料和磁性材料组合而成,具有高选择性、良好分散性和可多次重复利用等优点,在环境、医学和生物学研究领域应用广泛。本文介绍了MMOFs材料的四种合成方法,包括嵌入法、叠层法、封装法和混合法,其中嵌入法是指将磁性颗粒材料镶嵌在MOFs表面,叠层法是将MOFs层覆盖和叠加生长在官能化磁性颗粒材料表面,封装法是MOFs材料围绕磁性颗粒在其周围生长并将其包埋起来,混合法是将MOFs和磁性颗粒物通过物理或化学作用发生聚合合成。MOFs与磁性颗粒材料结合形成的MMOFs,既保留了MOFs材料的结构与性能,又增添了颗粒材料的磁性,从而大大拓展了MOFs的应用范围。鉴于MMOFs可携带特定的物质释放于指定位置,容易从复杂基质中分离,并可通过外部磁性进行定位与收集等优势与特点,其在生物医药、环境样品预处理和催化等领域得到了广泛的应用。     

金属-有机骨架及其功能材料在食品和水有害物质预处理中的应用

食品安全问题是关系人民生命健康和经济社会和谐发展的重大问题。食品类样品残存的痕量有毒有害物质对人体健康产生潜在危害。因此,需要高效的吸附材料用于食品类样品预处理及检测。金属-有机骨架材料(metal-organic frameworks, MOFs) 是一类新型的多孔功能材料,具有高孔隙度、高比表面积、结构可设计与调控、孔径可调及良好的化学和热稳定性等优点。MOFs的早期研究主要集中在结构及功能化设计方面,近年来MOFs及其功能材料在各领域的潜在应用逐渐成为新的研究热点。MOFs具有高度发达的孔隙结构,易通过功能化改变材料表面性质,不同的金属元素和配体种类,以及配位方式的多样化特性,极大地丰富固相萃取的固定相材料种类。尤其是在复杂基质样品预处理中,MOFs及其功能材料表现出强富集能力、强抗基质干扰能力、优异的选择性以及环境友好等优势。本文综述了近几年MOFs及其功能材料在食品和水样品中有害物质预处理方面的研究进展,并对这类材料应用在食品安全分析方面的发展进行了展望。     

金属-有机骨架材料用于废水处理

废水中的各种有害物质常常具有生物毒性或致癌性,因此如何高效、节能地处理水体污染是一个亟待解决的重要问题。金属-有机骨架材料(metal-organic frameworks, MOFs)是一种新型纳米多孔材料,具有种类多样性、结构可设计性与可调控性、高比表面积及良好的热稳定性等优点,已成为当前化学、材料学科的一个研究热点, 在多个领域显示出潜在的应用前景,尤其是在分离方面。与气相分离相比,MOFs用于液相分离的研究较少。本文综述了近年来MOFs用于含有染料、药物、醇、芳香族化合物、重金属离子及其他离子的废水处理的研究进展,重点剖析了MOFs的孔结构、骨架电荷及功能性对分离效果的影响,并结合本课题组的研究工作,对这种新型多功能材料在水处理方面的前景和今后的研究重点作了展望。     

多酸@金属-有机骨架材料的制备及其在废水处理中的应用

废水中的污染物由于其成分复杂、生物毒性大和难降解等特点,危害人体健康,因此,寻找开发一些能有效去除废水中的剧毒和难降解污染物的吸附剂成为亟待解决的问题.金属-有机骨架材料(MOFs)由于结构有序且多样、拓扑结构丰富、孔隙度超高、比表面积大、骨架结构稳定和易于掺杂其他组分等特点,使其在吸附领域得到了广泛的关注.多金属氧酸...     

疏水金属-有机骨架的合成及应用进展

金属-有机骨架（MOFs）作为一类新颖的多孔材料在诸多领域备受关注。然而,大多数MOFs因结构特性在水中易分解,限制了其应用。制备疏水MOFs可改善其水稳定性,并可拓展其在水体系中的应用。本文综述了疏水MOFs的合成及在催化、油水分离、污染物去除和气体吸附等方面的应用进展,并对其发展方向进行了展望。     

金属-有机骨架材料在色谱分离中的应用

金属-有机骨架材料（Metal-organic frameworks,MOFs）,因其具有较好的热稳定性、化学稳定性、可设计性等特点,广泛应用于气体吸附、物质分离、提纯、催化等领域,同时也作为模板制备各种功能材料.MOFs作为色谱分离的材料已得到了较多的研究与应用.按照被分离物质的类别,综述和总结了不同MOFs材料作为色谱固定相的分离效果,重点介绍了MOFs材料的色谱分离机理.MOFs材料的孔径、功能基团和不饱和金属位点在分离中起到重要的作用,最后对MOFs在色谱分离应用中的问题和前景进行了分析和展望.     

金属-有机框架材料的荧光探测应用进展

金属-有机框架材料(metal-organic frameworks,MOFs)是一类由金属离子或金属离子簇与有机配体自组装而成的杂化多孔材料。 极高的比表面积和孔隙率,组成和结构可调节等特点赋予该材料灵活的设计性和丰富的功能性。 金属-有机框架材料的金属离子、有机配体和装载的客体分子等皆可作为发光中心,并能对离子或小分子产生特异性荧光响应,因此在荧光探测方面有广泛应用。 本文主要综述了近年来金属-有机框架材料在荧光探测方向的研究进展以及应用前景。     

荧光金属-有机框架材料在金属离子检测中的研究进展

金属-有机框架材料(metal-organic frameworks, MOFs)作为一种新型的多孔材料,具有大的比表面积、可设计的框架结构、开放的金属活性位点以及易于化学修饰等优点,被广泛应用于识别、催化、吸附和分离等各个领域,已成为化学与材料研究领域的热点之一.在荧光传感领域, MOFs可以通过配体、金属中心的调控,以及配体与配体、配体和金属之间发生的能量转移或电荷转移,表现出丰富的荧光发射性能.本文根据荧光响应信号的变化(荧光淬灭型“turn-off”、荧光增强型“turn-on”和比率荧光型“ratiometric”)以及荧光传感的机理(竞争吸收、框架裂解、离子交换和配位作用),介绍了近年来荧光MOFs在金属离子检测领域的研究与应用现状,并进一步讨论了MOFs材料在该领域面临的挑战和发展趋势.     

Size- and Emission-Controlled Synthesis of Full-Color Luminescent Metal-Organic Frameworks for Tryptophan Detection

The development of nanoscaled luminescent metal–organic frameworks (nano-LMOFs) with organic linker-based emission to explore their applications in sensing, bioimaging and photocatalysis is of great interest as material size and emission wavelength both have remarkable influence on their performances. However, there is lack of platforms that can systematically tune the emission and size of nano-LMOFs with customized linker design. Herein two series of fcu - and csq -type nano-LMOFs, with precise size control in a broad range and emission colors from blue to near-infrared, were prepared using 2,1,3-benzothiadiazole and its derivative based ditopic- and tetratopic carboxylic acids as the emission sources. The modification of tetratopic carboxylic acids using OH and NH₂ as the substituent groups not only induces significant emission bathochromic shift of the resultant MOFs, but also endows interesting features for their potential applications. As one example, we show that the non-substituted and NH₂-substituted nano-LMOFs exhibit turn-off and turn-on responses for highly selective and sensitive detection of tryptophan over other nineteen natural amino acids. This work sheds light on the rational construction of nano-LMOFs with specific emission behaviours and sizes, which will undoubtedly facilitate their applications in related areas.     

羧酸类金属有机框架材料的合成及应用

金属-有机框架材料(Metal-Organic?Frameworks,简称MOFs)是由金属离子（簇）与有机桥接配体通过配位共价键或弱相互作用自组装形成的一类具有分子内孔隙的有机-无机杂化材料。羧酸类MOFs材料中金属中心和有机羧酸配体的可变性导致了其结构和功能的多样性,在气体的吸附与分离、荧光、传感、药物传输以及电催化等多个领域展现了独特的应用前景,并被认为是当今科学上最有前途的材料之一。对于有机配体的选择,从早期易坍塌的含氮杂环类配体过渡到了如今稳定性好的羧酸类配体,解决了不少以前出现的MOFs材料结构单一易坍塌问题。     

Fiber Integrated Metal-Organic Frameworks as Functional Components in Smart Textiles

Owing to high modularity and synthetic tunability, metal–organic frameworks (MOFs) on textiles are poised to contribute to the development of state-of-the-art wearable systems with multifunctional performance. While these composite materials have demonstrated promising functions in sensing, filtration, detoxification, and biomedicine, their applicability in multifunctional systems is only beginning to materialize. This review highlights the multifunctionality and versatility of MOF-integrated textile systems. It summarizes the operational goals of MOF@textile composites, encompassing sensing, filtration, detoxification, drug delivery, UV protection, and photocatalysis. Building upon these recent advances, this review concludes with an outlook on emerging opportunities for the diverse applications of MOF@textile systems in the realm of smart wearables.     

Reticular Synthesis of Metal-Organic Frameworks by 8-Connected Quadrangular Prism Ligands for Water Harvesting

Utilization of rigid, highly connected organic linkers is critical for the reticular synthesis of functional metal–organic frameworks (MOFs). However, highly-stable MOFs (e.g. Al/Cr/Zr-based MOFs) based on rigid ligands with more than 6 coordinating functions have been rarely achieved thus far. Herein, we describe the construction of two bcu Zr-based MOFs (named ZrMOF-1 and ZrMOF-2) from peripherally extended pentiptycene ligands (H₈PEP-1 and H₈PEP-2) with rigid quadrangular prism shape possessing 8 carboxylic groups at the prism vertices. Particularly, ZrMOF-1 exhibits microporous structure with large Bruno-Emmett-Teller surface area and high water stability, endowing it a promising water harvesting material with a high water uptake capacity of 0.83 g_H2O g_MOF⁻¹ at P/P₀=0.90 and 25 °C, a steep uptake at a low P/P₀ of 0.30, and excellent durability over 500 water adsorption-desorption cycles. Moreover, self-consistent charge density functional tight-binding calculations were carried out, rationalizing the water adsorbing process and amount in ZrMOF-1.     

Metal-Organic Frameworks for Photocatalytic Water Splitting and CO2 Reduction

Photocatalytic water splitting and carbon dioxide (CO₂) reduction provide promising solutions to global energy and environmental issues. In recent years, metal-organic frameworks (MOFs), a class of crystalline porous solids featuring well-defined and tailorable structures as well as high surface areas, have captured great interest toward photocatalytic water splitting and CO₂ reduction. In this review, the semiconductor-like behavior of MOFs is first discussed. We then summarize the recent advances in photocatalytic water splitting and CO₂ reduction over MOF-based materials and focus on the unique advantage of MOFs for clarifying the structure-property relationship in photocatalysis. In addition, some representative characterization techniques have been presented to unveil the photocatalytic kinetics and reaction intermediates in MOF-based systems. Finally, the challenges, and perspectives for future directions are proposed.     

Turning on Asymmetric Catalysis of Achiral Metal-Organic Frameworks by Imparting Chiral Microenvironment

The development of heterogeneous asymmetric catalysts has attracted increasing interest in synthetic chemistry but mostly relies on the immobilization of homogeneous chiral catalysts. Herein, a series of chiral metal–organic frameworks (MOFs) have been fabricated by anchoring similar chiral hydroxylated molecules (catalytically inactive) with different lengths onto Zr-oxo clusters in achiral PCN-222(Cu). The resulting chiral MOFs exhibit regulated enantioselectivity up to 83 % ee in the asymmetric ring-opening of cyclohexene oxide. The chiral molecules furnished onto the catalytic Lewis sites in the MOF create multilevel microenvironment, including the hydrogen interaction between the substrate and the chiral −OH group, the steric hindrance endowed by the benzene ring on the chiral molecules, and the proximity between the catalytic sites and chiral molecules confined in the MOF pores, which play crucial roles and synergistically promote chiral catalysis. This work nicely achieves heterogeneous enantioselective catalysis by chiral microenvironment modulation around Lewis acid sites.     

Modular Functionalization of Metal-Organic Frameworks for Nitrogen Recovery from Fresh Urine**

Nitrogen recovery from wastewater represents a sustainable route to recycle reactive nitrogen (Nr). It can reduce the demand of producing Nr from the energy-extensive Haber-Bosch process and lower the risk of causing eutrophication simultaneously. In this aspect, source-separated fresh urine is an ideal source for nitrogen recovery given its ubiquity and high nitrogen contents. However, current techniques for nitrogen recovery from fresh urine require high energy input and are of low efficiencies because the recovery target, urea, is a challenge to separate. In this work, we developed a novel fresh urine nitrogen recovery treatment process based on modular functionalized metal–organic frameworks (MOFs). Specifically, we employed three distinct modification methods to MOF-808 and developed robust functional materials for urea hydrolysis, ammonium adsorption, and ammonia monitoring. By integrating these functional materials into our newly developed nitrogen recovery treatment process, we achieved an average of 75 % total nitrogen reduction and 45 % nitrogen recovery with a 30-minute treatment of synthetic fresh urine. The nitrogen recovery process developed in this work can serve as a sustainable and efficient nutrient management that is suitable for decentralized wastewater treatment. This work also provides a new perspective of implementing versatile advanced materials for water and wastewater treatment.     

Integration of Metal-Organic Frameworks with Bi-Nanoprobes as Dual-Emissive Ratiometric Sensors for Fast and Highly Sensitive Determination of Food Hazards

Functional nanoprobes which detect specific food hazards quickly and simply are still in high demand in the field of food-safety inspection research. In the present work, a dual-emission metal-organic framework-based ratiometric fluorescence probe was integrated to detect Cu²⁺ and Pb²⁺ with rapidness and ease. Specifically, quantum dots (QDs) and carbon quantum dots (CQDs) were successfully embedded into zeolitic imidazolate framework-67 (ZIF-67) to function as a novel ratiometric fluorescent sensing composite. The ratiometric fluorescence signal of CQDs/QDs@ZIF-67 was significantly aligned with the concentration of metal ions to give an extremely low detection limit of 0.3324 nM. The highly sensitive and selective CQDs/QDs@ZIF-67 composite showed potential for the rapid and cost-effective detection of two metal ions.     

Decoupling Redox Hopping and Catalysis in Metal-Organic Frameworks -based Electrocatalytic CO2 Reduction

Traditional MOF e-CRR, constructed from catalytic linkers, manifest a kinetic bottleneck during their multi-electron activation. Decoupling catalysis and charge transport can address such issues. Here, we build two MOF/e-CRR systems, CoPc@NU-1000 and TPP(Co)@NU-1000, by installing cobalt metalated phthalocyanine and tetraphenylporphyrin electrocatalysts within the redox active NU-1000 MOF. For CoPc@NU-1000, the e-CRR responsive Co^I/0 potential is close to that of NU-1000 reduction compared to the TPP(Co)@NU-1000. Efficient charge delivery, defined by a higher diffusion (D_hop=4.1×10⁻¹² cm² s⁻¹) and low charge-transport resistance ( =59.5 Ω) in CoPC@NU-1000 led FE_CO=80 %. In contrast, TPP(Co)@NU-1000 fared a poor FE_CO=24 % (D_hop=1.4×10⁻¹² cm² s⁻¹ and =91.4 Ω). For such a decoupling strategy, careful choice of the host framework is critical in pairing up with the underlying electrochemical properties of the catalysts to facilitate the charge delivery for its activation.     

Spatial Distribution of Nitrogen Binding Sites in Metal-Organic Frameworks for Selective Ethane Adsorption and One-Step Ethylene Purification

The one-step purification of ethylene (C₂H₄) from mixtures containing ethane (C₂H₆) and acetylene (C₂H₂) is an industrially important yet challenging process. In this work, we present a site-engineering strategy aimed at manipulating the spatial distribution of binding sites within a confined pore space. We realized successfully by incorporating nitrogen-containing heterocycles, such as indole-5-carboxylic acid (Ind), benzimidazole-5-carboxylic acid (Bzz), and indazole-5-carboxylic acid (Izo), into the robust MOF-808 platform via post-synthetic modification. The resulting functionalized materials, namely MOF-808-Ind, MOF-808-Bzz, and MOF-808-Izo, demonstrated significantly improved selectivity for C₂H₂ and C₂H₆ over C₂H₄. MOF-808-Bzz with two uniformly distributed nitrogen binding sites gave the optimal geometry for selective ethane trapping through multiple strong C−H⋅⋅⋅N hydrogen bonds, leading to the highest C₂H₂/C₂H₄ and C₂H₆/C₂H₄ combined selectivities among known MOFs. Column breakthrough experiments validated its ability to purify C₂H₄ from ternary C₂H₂/C₂H₄/C₂H₆ mixtures in a single step.