金属有机骨架化合物（MOFs）作为储氢材料的研究进展*

氢的储存对于21世纪氢经济时代的发展至关重要。金属有机骨架化合物（MOFs）因具有纯度高、结晶度高、成本低、能够大批量生产和结构可控等优点,在气体存储尤其是氢的存储方面展示出广阔的应用前景。本文详细综述了近年来MOFs类化合物（MOF-5、IRMOFs和MMOMs）作为储氢材料的研究进展,介绍了各种用于改善MOFs材料储氢性能的结构改性方法,总结了MOFs储氢材料在理论模拟计算方面的研究进展,并指出了MOFs储氢材料目前存在的不足和发展方向。     

Promotion of Proton Conductivity by Encapsulation of Metal-Organic Polyhedra in Metal-Organic Frameworks

A Zr-based metal-organic polyhedron (MOP) was self-assembled in a porous MOF host, DUT-68, successfully to synthesize MOP-1@DUT-68. The MOP guest (MOP-1) has a diameter of about 20 Å, larger than that of the square windows (pore sizes of ∼14 Å) of DUT-68 but smaller than that of the rhombicuboctahedral cage (27.7 Å), which means that the migration and leaching of MOP-1 could be effectively prohibited if MOP-1 is encapsulated in the MOF′s cavities. The proton conductivity of MOP-1@DUT-68 is 1.14×10⁻³ S cm⁻¹ (at 80 °C under 98 % relative humidity), which is three orders of magnitude higher than that of DUT-68. Compared with MOP-1⊂DUT-68, which was synthesized by impregnation, MOP-1@DUT-68 is more prone to form faster proton-conduction pathways and thus provides higher proton conductivity.     

二维导电金属有机骨架材料

金属有机骨架(MOFs)是由金属离子或簇与有机配体以配位键组装而成的晶态多孔材料,其高的孔隙率及功能可设计性使其广泛应用于各种领域.然而,传统MOFs多数电导率非常低,这严重制约了其在电学相关领域的发展.近年来,导电金属有机骨架尤其是二维导电金属有机骨架(2D ECMOFs)材料因其结构中独特的π-π堆积及π-d共轭作...     

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。     

Advances of Metal‐Organic Frameworks in Energy and Environmental Applications

Nowadays, energy shortage and environmental pollution issues are increasingly severe and urgent to be solved. The effective storage and use of environmentally friendly fuels and removal of harmful gases from the environment are great challenges and of great importance both for the environment protection and for human health. Porous metal‐organic frameworks (MOFs) are highly ordered crystalline materials formed by the self‐assembly process of metal ions and organic ligands. Their good features such as ultrahigh porosity, large surface area, structural diversity and functionalities make them promising candidates for applications in energy and environmental fields. MOF thin films and MOF composites have also been investigated to further enhance the properties and introduce new functionalities. This review provides an overview of the synthesis methods of pristine MOFs, MOF thin films and MOF composites, and significant advances of MOFs in energy and environment applications such as energy storage (H₂, CH₄), CO₂ capture and separation, adsorption removal and sensing of harmful gases in the environment.     

Incorporating Transition-Metal Phosphides Into Metal-Organic Frameworks for Enhanced Photocatalysis

Metal-organic frameworks (MOFs) have been shown to be an excellent platform in photocatalysis. However, to suppress electron–hole recombination, a Pt cocatalyst is usually inevitable, especially in photocatalytic H₂ production, which greatly limits practical application. Herein, for the first time, monodisperse, small-size, and noble-metal-free transitional-metal phosphides (TMPs; for example, Ni₂P, Ni₁₂P₅), are incorporated into a representative MOF, UiO-66-NH₂, for photocatalytic H₂ production. Compared with the parent MOF and their physical mixture, both TMPs@MOF composites display significantly improved H₂ production rates. Thermodynamic and kinetic studies reveal that TMPs, behaving similar ability to Pt, greatly accelerate the linker-to-cluster charge transfer, promote charge separation, and reduce the activation energy of H₂ production. Significantly, the results indicate that Pt is thermodynamically favorable, yet Ni₂P is kinetically preferred for H₂ production, accounting for the higher activity of Ni₂P@UiO-66-NH₂ than Pt@UiO-66-NH₂.     

金属有机骨架材料在吸附分离研究中的应用进展

作为一种新型的纳米多孔材料,金属有机骨架材料（Metal-Organic Frameworks,MOFs）在近二十余年中得到了飞速的发展.MOFs材料由无机金属离子和有机配体通过自组装形成,具有许多优于传统多孔材料的特性.超高的比表面积、较高的孔隙率、可调的孔道尺寸、良好的热稳定性和化学稳定性使得MOFs材料在多个领域中展现出了广阔的应用前景.随着研究的不断深入,MOFs材料被广泛应用于催化反应、吸附分离、生物医学等领域中,并表现出了优异的效果.本文着力于近年来MOFs材料在吸附分离研究中的进展,重点介绍了这类材料在能源气体贮存、碳捕获、膜分离、液相吸附、色谱的分离净化方面的应用,并对其今后的发展进行了展望.     

Amino-Functionalized Titanium Based Metal-Organic Framework for Photocatalytic Hydrogen Production

Photocatalytic hydrogen production using stable metal-organic frameworks (MOFs), especially the titanium-based MOFs (Ti-MOFs) as photocatalysts is one of the most promising solutions to solve the energy crisis. However, due to the high reactivity and harsh synthetic conditions, only a limited number of Ti-MOFs have been reported so far. Herein, we synthesized a new amino-functionalized Ti-MOFs, named NH₂-ZSTU-2 (ZSTU stands for Zhejiang Sci-Tech University), for photocatalytic hydrogen production under visible light irradiation. The NH₂-ZSTU-2 was synthesized by a facile solvothermal method, composed of 2,4,6-tri(4-carboxyphenylphenyl)-aniline (NH₂-BTB) triangular linker and infinite Ti-oxo chains. The structure and photoelectrochemical properties of NH₂-ZSTU-2 were fully studied by powder X-ray diffraction, scanning electron microscope, nitro sorption isotherms, solid-state diffuse reflectance absorption spectra, and Mott–Schottky measurements, etc., which conclude that NH₂-ZSTU-2 was favorable for photocatalytic hydrogen production. Benefitting from those structural features, NH₂-ZSTU-2 showed steady hydrogen production rate under visible light irradiation with average photocatalytic H₂ yields of 431.45 μmol·g⁻¹·h⁻¹ with triethanolamine and Pt as sacrificial agent and cocatalyst, respectively, which is almost 2.5 times higher than that of its counterpart ZSTU-2. The stability and proposed photocatalysis mechanism were also discussed. This work paves the way to design Ti-MOFs for photocatalysis.     

Metal-Organic Frameworks for Efficient Electrochemical Reduction of Carbon Dioxide

The large concentration of carbon dioxide (CO₂) in the atmosphere can be utilized in industrial production using effective electrocatalysts such as metal-organic frameworks (MOFs). Due to good properties such as high surface area, designable functionality, and uniform constitution, MOFs are regarded as promising electrocatalysts for the carbon dioxide electrochemical reduction reaction (eCO₂RR). This review covers the importance, challenges, and mechanism of eCO₂RR, and simply discusses the progress in the synthesis methods and characterization of MOFs. The review also thoroughly discusses the advances of single metal-based MOFs, mixed metal-based MOFs, and MOF derivatives as electrocatalysts for efficient eCO₂RR.     

二氧化碳在金属-有机骨架材料中吸附的阶梯现象

采用巨正则系综蒙特卡罗(GCMC)模拟方法, 对二氧化碳在5种具有相同拓扑结构的金属-有机骨架材料(IRMOFs), 即IRMOF-1, -8, -10, -14, -16中吸附产生的阶梯现象进行了详细的研究. 结果表明: 低温条件下, 孔径越大的IRMOFs越容易发生阶梯现象; 发生阶梯现象的转变压力与能够发生阶梯现象的转变温度都与孔径呈线性关系. 此外, 模拟结果进一步验证了二氧化碳分子之间的静电作用力是阶梯现象发生的关键因素. 这些规律将为金属-有机骨架材料(MOFs)的设计和改性以及二氧化碳在混合气体中的吸附分离提供有用的信息.     

金属-有机骨架材料中吸附气体的扩散速率

采用分子动力学方法,以甲烷为探针分子研究了不同压力条件下气体在具有不同孔道结构的金属-有机骨架材料(MOFs)中的扩散速率.通过计算气体在八种材料中的自扩散系数,并结合气体分子在材料中的质心分布图等,讨论了气体扩散速率与孔道结构之间的关系.研究结果表明:对于同时含有孔笼(pocket)和三维正交孔道(channel)结构的MOF材料(P-C材料),低压时甲烷气体吸附在孔笼结构中,随着压力的升高,气体分子开始进入正交孔道,同时其自扩散系数增加;而对于只含有三维立方孔道结构的IRMOF(isoreticular MOF)系列材料,在中低压范围内,气体分子在其中的自扩散系数随压力变化较小.当压力进一步升高时,气体分子在材料孔道中的吸附逐渐接近饱和,其自扩散系数均降低.因此,在不同MOF材料中气体分子扩散速率的差异主要取决于孔道结构的不同.对P-C材料,中低压下通过控制压力可以控制气体在其中的扩散速率,从而为MOF材料在气体存储、分离等方面的实际应用提供参考信息.     

金属-有机框架材料在催化炔烃半氢化反应中的应用

炔烃的半氢化反应在有机合成和精细化工领域具有重要地位,如何同时兼顾反应活性和选择性仍存在很大挑战。目前已有多种材料被应用于相关催化,其中金属-有机骨架(MOFs)及其复合材料受到越来越多关注。MOFs的多孔性、结构可修饰性、空间限域效应、协同催化等优点,使其在炔烃的半氢化反应中表现出独特的应用前景。本文综述了MOFs及其复合材料在炔烃的半氢化反应生成烯烃过程中的应用,主要根据活性催化位点的类别展开介绍,重点阐述了不同体系中催化效果和结构之间的关系。     

金属-有机框架作为异相催化剂的表征方法概述

作为一类具有大的比表面积、高孔隙率、合成方便、骨架规模可变、化学可修饰以及结构组成多样等优点的新型多孔材料,金属-有机框架（MOFs）在光电材料、药物传输、气体吸附分离及催化等领域有着广阔的应用前景,成为近年来研究的热点。异相催化是MOFs最具发展潜力的应用领域之一,各种表征方法和研究手段是开展MOFs异相催化研究的工作基础。本文主要围绕表征MOFs作为异相催化剂的常用技术手段进行介绍,包括X-射线单晶衍射、X-射线粉末衍射、热重分析、红外光谱/拉曼光谱分析、透射/扫描电镜等,旨在为开展相关MOFs催化研究提供一定参考。     

Design Rules for Metal-Organic Framework Stability in High-Pressure Hydrogen Environments

Stability of metal-organic frameworks (MOFs) under hydrogen is of particular importance for a diverse range of applications, including catalysis, gas separations, and hydrogen storage. Hydrogen in gaseous form is known to be a strong reducing agent and can potentially react with the secondary building units of a MOF and decompose the porous framework structure. Moreover, rapid pressure swings expected in vehicular hydrogen storage could create significant mechanical stresses within MOF crystals that cause partial or complete pore collapse. In this work, we examined the stability of a structurally representative suite of MOFs by testing them under both static (70 MPa) and dynamic hydrogen exposure (0.5 to 10 MPa, 1000 pressure cycles) at room temperature. We aim to provide stability information for development of near room-temperature hydrogen storage media based on MOFs and suggest framework design rules to avoid materials unstable for hydrogen storage under relevant technical conditions.     

Failure-Experiment-Supported Optimization of Poorly Reproducible Synthetic Conditions for Novel Lanthanide Metal-Organic Frameworks with Two-Dimensional Secondary Building Units**

Novel metal–organic frameworks containing lanthanide double-layer-based secondary building units (KGF-3) were synthesized by using machine learning (ML). Isolating pure KGF-3 was challenging, and the synthesis was not reproducible because impurity phases were frequently obtained under the same synthetic conditions. Thus, dominant factors for the synthesis of KGF-3 were identified, and its synthetic conditions were optimized by using two ML techniques. Cluster analysis was used to classify the obtained powder X-ray diffractometry patterns of the products and thus automatically determine whether the experiments were successful. Decision-tree analysis was used to visualize the experimental results, after extracting factors that mainly affected the synthetic reproducibility. Water-adsorption isotherms revealed that KGF-3 possesses unique hydrophilic pores. Impedance measurements demonstrated good proton conductivities (σ=5.2×10⁻⁴ S cm⁻¹ for KGF-3(Y)) at a high temperature (363 K) and relative humidity of 95 % RH.     

纳米孔洞金属-有机骨架催化氧化苯甲醇动力学研究

具有纳米孔洞的金属-有机骨架材料Cu3（BTC）2（H2O）3为催化剂,过氧化氢为氧化剂,利用紫外可见光谱研究其催化氧化苯甲醇生成苯甲醛的催化反应动力学行为,系统地讨论了纳米孔洞金属-有机骨架材料的催化动力学。研究结果表明,随着反应介质的pH、催化剂与反应底物的摩尔比和反应温度的升高,准一级反应速率常数kobsd也会随...     

金属有机框架质子导体及其质子交换膜的研究进展

质子交换膜是新型燃料电池的关键组件之一.以Nafion为代表的商用全氟磺酸质子交换膜成本较高、操作温度较低,限制了宽温度范围下的大规模应用.金属有机框架材料(Metal Organic Framework, MOFs)因其比表面积大、结构规整、可设计性强等优点,在质子交换领域备受关注.作者从三方面综述了MOFs质子导体的相关研究.第一部分主要介绍了MOFs传导质子的作用机理;第二部分从有水/无水条件下工作的两种不同MOFs出发综述了MOFs质子导体的相关发展;第三部分系统回顾了MOFs质子交换膜的相关研究,包括MOFs薄膜与MOFs混合基质膜结构.最后指出了MOFs质子导体及其质子交换膜研究中尚未解决的问题,并展望该领域的未来研究方向.     

功能化金属有机骨架材料在放射性离子检测中的应用

With the shortage of fossil energy and increasing environmental pollution, nuclear energy has received extensive attention by its virtue of high energy density and low emission of greenhouse gases. However, radioactive nuclear waste remains a serious task for its safe and effective disposal due to their harmful effects on human health and the environment. As a new type of multifunctional nanomaterial, metal-organic frameworks (MOFs) are synthesized via the self-assembling combination of inorganic metals and organic ligands. Compared with traditional porous materials, MOFs have broad application prospects in the adsorption and detection of radioactive ions. In this paper, we reviewed the functional modification strategies of MOFs and summarized the progress in the applications of functionalized MOFs in removal and fluorescence sensing of contaminated ions in recent years. Besides, the future development trends are also discussed.     

Conductive Metal-Organic Frameworks: Electronic Structure and Electrochemical Applications

Smarter and minimization of devices are consistently substantial to shape the energy landscape. Significant amounts of endeavours have come forward as promising steps to surmount this formidable challenge. It is undeniable that material scientists were contemplating smarter material beyond purely inorganic or organic materials. To our delight, metal-organic frameworks (MOFs), an inorganic-organic hybrid scaffold with unprecedented tunability and smart functionalities, have recently started their journey as an alternative. In this review, we focus on such propitious potential of MOFs that was untapped over a long time. We cover the synthetic strategies and (or) post-synthetic modifications towards the formation of conductive MOFs and their underlying concepts of charge transfer with structural aspects. We addressed theoretical calculations with the experimental outcomes and spectroelectrochemistry, which will trigger vigorous impetus about intrinsic electronic behaviour of the conductive frameworks. Finally, we discussed electrocatalysts and energy storage devices stemming from conductive MOFs to meet energy demand in the near future.     

稀土金属-有机框架在同分异构体传感材料中的应用

基于稀土金属离子独特的电子结构,稀土金属-有机框架的光致发光具有发射峰尖锐、量子产率高和发光寿命长等特点,可应用于针对特定功能化学物种的光学传感材料.稀土金属离子高的配位数和丰富的配位模式,使得稀土金属-有机框架具有结构多样性和可调性,可与不同的化学物种在结构和能级两个方面相匹配,是其具有传感功能的基础.关于同分异构体...