共查询到20条相似文献,搜索用时 31 毫秒
1.
Neng‐Xiu Zhu Zhang‐Wen Wei Cheng‐Xia Chen Dawei Wang Chen‐Chen Cao Qian‐Feng Qiu Ji‐Jun Jiang Hai‐Ping Wang Cheng‐Yong Su 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(47):17189-17196
We transformed the hydrophilic metal–organic framework (MOF) UiO‐67 into hydrophobic UiO‐67‐R s (R=alkyl) by introducing alkyl chains into organic linkers, which not only protected hydrophilic Zr6O8 clusters to make the MOF interspace superoleophilic, but also led to a rough crystal surface beneficial for superhydrophobicity. The UiO‐67‐R s displayed high acid, base, and water stability, and long alkyl chains offered better hydrophobicity. Good hydrophobicity/oleophilicity were also possible with mixed‐ligand MOFs containing metal‐binding ligands. Thus, a (super)hydrophobic MOF catalyst loaded with Pd centers efficiently catalyzed Sonogashira reactions in water at ambient temperature. Studies of the hydrophobic effects of the coordination interspace and the outer surface suggest a simple de novo strategy for the synthesis of superhydrophobic MOFs that combine surface roughness and low surface energy. Such MOFs have potential for environmentally friendly catalysis and water purification. 相似文献
2.
《中国化学》2017,35(10):1501-1511
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. 相似文献
3.
Subhajit Laha Dr. Darsi Rambabu Dr. Sohini Bhattacharyya Prof. Tapas Kumar Maji 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(64):14671-14678
Various hierarchical micro/mesoporous MOFs based on {[Al(μ-OH)(1,4-NDC)]⋅H2O} ( MOF1 ) with tunable porosities (pore volume and surface area) have been synthesized by assembling AlIII and 1,4-NDC (1,4-naphthalenedicarboxylate) under microwave irradiation by varying water/ethanol solvent ratio. Water/ethanol mixture has played a crucial role in the mesopore generation in MOF1M25 , MOF1M50 , and MOF1M75 , which is achieved by in situ formation of water/ethanol clusters. By adjusting the ratio of water/ethanol, the particle size, surface area and micro/mesopore volume fraction of the MOFs are controlled. Furthermore, reaction time plays a critical role in mesopore formation as realized by varying reaction time for the MOF with 50 % ethanol ( MOF1M50 ). Additionally, hierarchical MOF ( MOF1M50 ) has been used as a template for the stabilization of MAPbBr3 (MA=methylammonium) perovskite quantum dots (PQDs). MAPbBr3 PQDs are grown inside MOF1M50 , where mesopores control the size of PQDs which leads to quantum confinement. 相似文献
4.
Chao Liu Jing Wang Jingjing Wan Yan Cheng Rong Huang Chaoqi Zhang Wenli Hu Guangfeng Wei Chengzhong Yu 《Angewandte Chemie (International ed. in English)》2020,59(9):3630-3637
Amorphous metal–organic frameworks (aMOFs) are an emerging family of attractive materials with great application potential, however aMOFs are usually prepared under harsh conditions and aMOFs with complex compositions and structures are rarely reported. In this work, an aMOF‐dominated nanocomposite (aMOF‐NC) with both structural and compositional complexity has been synthesized using a facile approach. A ligand‐competition amorphization mechanism is proposed based on experimental and density functional theory calculation results. The aMOF‐NC possesses a core–shell nanorod@nanosheet architecture, including a Fe‐rich Fe‐Co‐aMOF core and a Co‐rich Fe‐Co‐aMOF shell in the core–shell structured nanorod, and amorphous Co(OH)2 nanosheets as the outer layer. Benefiting from the structural and compositional heterogeneity, the aMOF‐NC demonstrates an excellent oxygen evolution reaction activity with a low overpotential of 249 mV at 10.0 mA cm?2 and Tafel slope of 39.5 mV dec?1. 相似文献
5.
Direct Fabrication of Free‐Standing MOF Superstructures with Desired Shapes by Micro‐Confined Interfacial Synthesis 下载免费PDF全文
Jin‐Oh Kim Dr. Kyoung‐Ik Min Hyunwoo Noh Dong‐Hwi Kim Prof. Dr. Soo‐Young Park Prof. Dr. Dong‐Pyo Kim 《Angewandte Chemie (International ed. in English)》2016,55(25):7116-7120
Recently, metal–organic frameworks (MOFs) with multifunctional pore chemistry have been intensively investigated for positioning the desired morphology at specific locations onto substrates for manufacturing devices. Herein, we develop a micro‐confined interfacial synthesis (MIS) approach for fabrication of a variety of free‐standing MOF superstructures with desired shapes. This approach for engineering MOFs provides three key features: 1) in situ synthesis of various free‐standing MOF superstructures with controlled compositions, shape, and thickness using a mold membrane; 2) adding magnetic functionality into MOF superstructures by loading with Fe3O4 nanoparticles; 3) transferring the synthesized MOF superstructural array on to flat or curved surface of various substrates. The MIS route with versatile potential opens the door for a number of new perspectives in various applications. 相似文献
6.
Lingyun Chen Yongming Shen Junfeng Bai Chunzhao Wang 《Journal of solid state chemistry》2009,182(8):2298-2306
We describe here a one-step solid-state process for the synthesis of metal three-dimensional (3D) superstructures from a metal-organic framework (MOF). Novel symmetrical coralloid Cu 3D superstructures with surface interspersed with clusters of Cu nanoparticles were successfully synthesized by thermolysis of the [Cu3(btc)2] (btc=benzene-1,3,5-tricarboxylato) MOF in a one-end closed horizontal tube furnace (OCTF). The obtained products were characterized by TGA, FT-IR, XRD, EDX, SEM, TEM, HRTEM and SAED. Different reaction conditions were discussed. Furthermore, the synthesized Cu samples were converted into CuO microstructures by in-situ calcination in the air. In addition, the possible formation mechanism was also proposed. This method is a simple and facile route, which builds a direct linkage between metal-carboxylate MOF crystals and metal nano- or microstructures and also opens a new application field of MOFs. 相似文献
7.
Mark Kalaj Prof. Dr. Seth M. Cohen 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(33):14088-14093
A UiO-66-NCS MOF was formed by postsynthetic modification of UiO-66-NH2. The UiO-66-NCS MOFs displays a circa 20-fold increase in activity against the chemical warfare agent simulant dimethyl-4-nitrophenyl phosphate (DMNP) compared to UiO-66-NH2, making it the most active MOF materials using a validated high-throughput screening. The −NCS functional groups provide reactive handles for postsynthetic polymerization of the MOFs into functional materials. These MOFs can be tethered to amine-terminated polypropylene polymers (Jeffamines) through a facile room-temperature synthesis with no byproducts. The MOFs are then crosslinked into a MOF–polythiourea (MOF–PTU) composite material, maintaining the catalytic properties of the MOF and the flexibility of the polymer. This MOF–PTU hybrid material was spray-coated onto Nyco textile fibers, displaying excellent adhesion to the fiber surface. The spray-coated fibers were screened for the degradation of DMNP and showed durable catalytic reactivity. 相似文献
8.
Behnam Ghalei Kazuki Wakimoto Chih Yi Wu Ali Pournaghshband Isfahani Takuma Yamamoto Kento Sakurai Masakazu Higuchi Bor Kae Chang Susumu Kitagawa Easan Sivaniah 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(52):19210-19216
The effect of organic ligands on the separation performance of Zr based metal–organic framework (Zr‐MOF) membranes was investigated. A series of Zr‐MOF membranes with different ligand chemistry and functionality were synthesized by an in situ solvothermal method and a coordination modulation technique. The thin supported MOF layers (ca. 1 μm) showed the crystallographic orientation and pore structure of original MOF structures. The MOF membranes show excellent selectivity towards hydrogen owing to the molecular sieving effect when the bulkier linkers were used. The molecular simulation confirmed that the constricted pore apertures of the Zr‐MOFs which were formed by the additional benzene rings lead to the decrease in the diffusivity of larger penetrants while hydrogen was not remarkably affected. The gas mixture separation factors of the MOF membranes reached to H2/CO2=26, H2/N2=13, H2/CH4=11. 相似文献
9.
《先进技术聚合物》2018,29(2):867-873
The push to advance efficient, renewable, and clean energy sources has brought with it an effort to generate materials that are capable of storing hydrogen. Metal–organic framework materials (MOFs) have been the focus of many such studies as they are categorized for their large internal surface areas. We have addressed one of the major shortcomings of MOFs (their processibility) by creating and 3D printing a composite of acrylonitrile butadiene styrene (ABS) and MOF‐5, a prototypical MOF, which is often used to benchmark H2 uptake capacity of other MOFs. The ABS‐MOF‐5 composites can be printed at MOF‐5 compositions of 10% and below. Other physical and mechanical properties of the polymer (glass transition temperature, stress and strain at the breaking point, and Young's modulus) either remain unchanged or show some degree of hardening due to the interaction between the polymer and the MOF. We do observe some MOF‐5 degradation through the blending process, likely due to the ambient humidity through the purification and solvent casting steps. Even with this degradation, the MOF still retains some of its ability to uptake H2, seen in the ability of the composite to uptake more H2 than the pure polymer. The experiments and results described here represent a significant first step toward 3D printing MOF‐5‐based materials for H2 storage. 相似文献
10.
《中国化学快报》2021,32(12):3817-3820
Developing metal-organic framework (MOF)-based materials with good cyclic stability is the key to their practical application. Fluorinated organic compounds are usually highly chemically stability due to the high electronegativity of fluorine. Also, the pillared-layer structures based on coordination bonds have better structure and thermal stability than those based on hydrogen bonds. Herein, the fluorinated pillared-layer [Ni(2,3,4,5-tetrafluorobenzoic acid)(4,4′-bipyridine)]n MOF ([Ni(TFBA)(Bpy)]n) materials were constructed through a facile room-temperature solution reaction and used as electrode materials for supercapacitors. Surprisingly, the size/morphology of Ni(TFBA)(Bpy)]n MOFs could be adjusted by varying the synthesis time. Benefting from the short ion diffusion length, unique pillar-layer structure, and strong intercomponent synergy of organic ligands, the Ni(TFBA)(Bpy)]n MOF microrods showed a higher electrochemical energy storage capability than bulk MOFs. At the same time, compared to the non-fluorinated [Ni(benzoic acid)(Bpy)]n MOFs (31.5% capacitance decay), the fluorinated Ni(TFBA)(Bpy)]n MOFs have a higher cycle stability with only 2.6% capacitance loss after 5000 cycles at 3 mA/cm2. 相似文献
11.
A UiO‐66‐NCS MOF was formed by postsynthetic modification of UiO‐66‐NH2. The UiO‐66‐NCS MOFs displays a circa 20‐fold increase in activity against the chemical warfare agent simulant dimethyl‐4‐nitrophenyl phosphate (DMNP) compared to UiO‐66‐NH2, making it the most active MOF materials using a validated high‐throughput screening. The ?NCS functional groups provide reactive handles for postsynthetic polymerization of the MOFs into functional materials. These MOFs can be tethered to amine‐terminated polypropylene polymers (Jeffamines) through a facile room‐temperature synthesis with no byproducts. The MOFs are then crosslinked into a MOF–polythiourea (MOF–PTU) composite material, maintaining the catalytic properties of the MOF and the flexibility of the polymer. This MOF–PTU hybrid material was spray‐coated onto Nyco textile fibers, displaying excellent adhesion to the fiber surface. The spray‐coated fibers were screened for the degradation of DMNP and showed durable catalytic reactivity. 相似文献
12.
Dr. Wei-Ling Jiang Bin Huang Meng-Xiang Wu Ye-Kai Zhu Dr. Xiao-Li Zhao Prof. Dr. Xueliang Shi Prof. Dr. Hai-Bo Yang 《化学:亚洲杂志》2021,16(23):3985-3992
Metal-organic frameworks (MOFs) consisting of organic radicals are of great interest because they have exhibited unique and intriguing optical, electronic, magnetic, and chemo-catalytic properties, and thus have demonstrated great potential applications in optical, electronic, and magnetic devices, and as catalysts. However, the preparation of MOFs bearing stable organic radicals is very challenging because most organic radicals are highly reactive and difficult to incorporate into the framework of MOFs. Herein we reported a post-synthetic modification strategy to prepare a novel MOF containing phenazine radical cations, which was used as heterogeneous catalyst for aza-Diels-Alder reaction. The zinc-based metal-organic framework Zn2(PHZ)2(dabco) ( N ) was successfully synthesized from 5,10-di(4-benzoic acid)-5,10-dihydrophenazine (PHZ), triethylene diamine (dabco) with Zn(NO3)2 ⋅ 6H2O by solvothermal method. The as-synthesized MOF N was partially oxidized by AgSbF6 to form MOF R containing ∼10% phenazine radical cation species. The resultant MOF R was found to keep the original crystal type of N and very persistent under ambient conditions. Consequently, MOF R was successfully employed in radical cation-catalyzed aza-Diels-Alder reactions with various imine substrates at room temperature with high reaction conversion. Moreover, heterogeneous catalyst MOF R was reusable up to five times without much loss of catalytic activity, demonstrating its excellent stability and recyclability. Therefore, the post-synthetic modification developed in this work is expected to become a versatile strategy to prepare radical-based MOFs for the application of heterogeneous catalysts in organic synthesis. 相似文献
13.
Fen Qiu John R. Edison Zdenek Preisler Yan‐Fang Zhang Guo Li Aizhao Pan Chih‐Hao Hsu Tracy M. Mattox Peter Ercius Chengyu Song Karen Bustillo Michael A. Brady Edmond W. Zaia Sohee Jeong Jeffrey B. Neaton Shixuan Du Stephen Whitelam Jeffrey J. Urban 《Angewandte Chemie (International ed. in English)》2018,57(40):13172-13176
We demonstrate the guiding principles behind simple two dimensional self‐assembly of MOF nanoparticles (NPs) and oleic acid capped iron oxide (Fe3O4) NCs into a uniform two‐dimensional bi‐layered superstructure. This self‐assembly process can be controlled by the energy of ligand–ligand interactions between surface ligands on Fe3O4 NCs and Zr6O4(OH)4(fumarate)6 MOF NPs. Scanning transmission electron microscopy (TEM)/energy‐dispersive X‐ray spectroscopy and TEM tomography confirm the hierarchical co‐assembly of Fe3O4 NCs with MOF NPs as ligand energies are manipulated to promote facile diffusion of the smaller NCs. First‐principles calculations and event‐driven molecular dynamics simulations indicate that the observed patterns are dictated by combination of ligand–surface and ligand–ligand interactions. This study opens a new avenue for design and self‐assembly of MOFs and NCs into high surface area assemblies, mimicking the structure of supported catalyst architectures, and provides a thorough fundamental understanding of the self‐assembly process, which could be a guide for designing functional materials with desired structure. 相似文献
14.
Dr. Chao Liu Dr. Jing Wang Prof. Jingjing Wan Dr. Yan Cheng Prof. Rong Huang Chaoqi Zhang Wenli Hu Dr. Guangfeng Wei Prof. Chengzhong Yu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(9):3659-3666
Amorphous metal–organic frameworks (aMOFs) are an emerging family of attractive materials with great application potential, however aMOFs are usually prepared under harsh conditions and aMOFs with complex compositions and structures are rarely reported. In this work, an aMOF-dominated nanocomposite (aMOF-NC) with both structural and compositional complexity has been synthesized using a facile approach. A ligand-competition amorphization mechanism is proposed based on experimental and density functional theory calculation results. The aMOF-NC possesses a core–shell nanorod@nanosheet architecture, including a Fe-rich Fe-Co-aMOF core and a Co-rich Fe-Co-aMOF shell in the core–shell structured nanorod, and amorphous Co(OH)2 nanosheets as the outer layer. Benefiting from the structural and compositional heterogeneity, the aMOF-NC demonstrates an excellent oxygen evolution reaction activity with a low overpotential of 249 mV at 10.0 mA cm−2 and Tafel slope of 39.5 mV dec−1. 相似文献
15.
Two new metal‐organic frameworks (MOF), [(CuCN)2 · (6‐mquin)2] ( 1 ) and [Me3SnCu(CN)2 · (quina)2(H2O)2] ( 2 ) (6‐mquin = 6‐methyl quinolone, quina = quinaldic acid) were synthesized and characterized. Single crystals of MOF 1 were characterized by IR and NMR spectroscopy, as well as X‐ray single crystal analysis. The structure of MOF 2 was studied by IR and NMR spectroscopy as well as computational studies. The structure of MOF 1 consists of 1D (CuCN)n chains, whereas the 6‐mquin ligands alternate on both sides of the chain. Hydrogen bonds play an essential role for the construction of the 3D network structure. On the other hand, the theoretical structural analysis of MOF 2 indicated that the Cu(CN)2 fragments represent the main building blocks of the structure, which are bridged by the Me3Sn+ cations to construct 1D infinite parallel zigzag chains. MOFs 1 and 2 were used as heterogeneous catalysts for the oxidative discoloration of methylene blue dye (MB) by H2O2. 相似文献
16.
Modification of Extended Open Frameworks with Fluorescent Tags for Sensing Explosives: Competition between Size Selectivity and Electron Deficiency 下载免费PDF全文
Bappaditya Gole Dr. Arun Kumar Bar Prof. Partha Sarathi Mukherjee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(8):2276-2291
Three new electron‐rich metal–organic frameworks ( MOF‐1 – MOF‐3 ) have been synthesized by employing ligands bearing aromatic tags. The key role of the chosen aromatic tags is to enhance the π‐electron density of the luminescent MOFs. Single‐crystal X‐ray structures have revealed that these MOFs form three‐dimensional porous networks with the aromatic tags projecting inwardly into the pores. These highly luminescent electron‐rich MOFs have been successfully utilized for the detection of explosive nitroaromatic compounds (NACs) on the basis of fluorescence quenching. Although all of the prepared MOFs can serve as sensors for NACs, MOF‐1 and MOF‐2 exhibit superior sensitivity towards 4‐nitrotoluene (4‐NT) and 2,4‐dinitrotoluene (DNT) compared to 2,4,6‐trinitrotoluene (TNT) and 1,3,5‐trinitrobenzene (TNB). MOF‐3 , on the other hand, shows an order of sensitivity in accordance with the electron deficiencies of the substrates. To understand such anomalous behavior, we have thoroughly analyzed both the steady‐state and time‐resolved fluorescence quenching associated with these interactions. Determination of static Stern–Volmer constants (KS) as well as collisional constants (KC) has revealed that MOF‐1 and MOF‐2 have higher KS values with 4‐NT than with TNT, whereas for MOF‐3 the reverse order is observed. This apparently anomalous phenomenon was well corroborated by theoretical calculations. Moreover, recyclability and sensitivity studies have revealed that these MOFs can be reused several times and that their sensitivities towards TNT solution are at the parts per billion (ppb) level. 相似文献
17.
Thermodynamics of the oxygen evolution electrocatalysis in a functionalized UiO‐66 metal‐organic frameworks 下载免费PDF全文
Terence Musho Jiangtian Li Nianqiang Wu 《International journal of quantum chemistry》2016,116(15):1153-1159
A density functional theory (DFT) approach was used to predict the thermodynamic energy barriers of the oxygen evolution reaction (OER) for three functionalized Metal‐organic Frameworks (MOFs). A UiO‐66(Zr) MOF design was selected for this study that incorporates three linker designs, a 1,4‐benzenedicarboxylate (BDC), BDC functionalized with an amino group (BDC + NH2), and BDC functionalized with nitro group (BDC + NO2). The study found several key differences between homogeneous planar catalyst thermodynamics and MOF‐based thermodynamics, the most significant being the non‐unique or heterogeneity of reaction sites. Additionally, the functionalization of the MOF was found to significantly influence the hydroperoxyl binding energy, which proves to be the largest hurdle for both oxide and MOF‐based catalyst. Both of these findings provide evidence that many of the limitations precluding planar homogeneous catalysts can be surpassed with a MOF‐based catalyst. The BDC + NH2 proved to be the best performing catalyst with a predicted over‐potential for spontaneous OER evolution to be 3.03eV. © 2016 Wiley Periodicals, Inc. 相似文献
18.
Souvik Pal Dr. Asamanjoy Bhunia Dr. Partha P. Jana Subarna Dey Dr. Jens Möllmer Prof. Dr. Christoph Janiak Dr. Hari Pada Nayek 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(7):2789-2792
A microporous La–metal‐organic framework (MOF) has been synthesized by the reaction of La(NO3)3 ? 6 H2O with a ligand 4,4′,4′′‐s‐triazine‐1,3,5‐triyltri‐p‐aminobenzoate (TATAB) featuring three carboxylate groups. Crystal structure analysis confirms the formation of 3D MOF with hexagonal micropores, a Brunauer–Emmett—Teller (BET) surface area of 1074 m2 g?1 and high thermal and chemical stability. The CO2 adsorption capacities are 76.8 cm3 g?1 at 273 K and 34.6 cm3 g?1 at 293 K, a highest measured CO2 uptake for a Ln–MOFs. 相似文献
19.
Cu3(hexaiminotriphenylene)2: An Electrically Conductive 2D Metal–Organic Framework for Chemiresistive Sensing 下载免费PDF全文
Dr. Michael G. Campbell Dr. Dennis Sheberla Sophie F. Liu Prof. Timothy M. Swager Prof. Mircea Dincă 《Angewandte Chemie (International ed. in English)》2015,54(14):4349-4352
The utility of metal–organic frameworks (MOFs) as functional materials in electronic devices has been limited to date by a lack of MOFs that display high electrical conductivity. Here, we report the synthesis of a new electrically conductive 2D MOF, Cu3(HITP)2 (HITP=2,3,6,7,10,11‐hexaiminotriphenylene), which displays a bulk conductivity of 0.2 S cm?1 (pellet, two‐point‐probe). Devices synthesized by simple drop casting of Cu3(HITP)2 dispersions function as reversible chemiresistive sensors, capable of detecting sub‐ppm levels of ammonia vapor. Comparison with the isostructural 2D MOF Ni3(HITP)2 shows that the copper sites are critical for ammonia sensing, indicating that rational design/synthesis can be used to tune the functional properties of conductive MOFs. 相似文献
20.
Zhicheng Zhang Yifeng Chen Xiaobin Xu Jingchao Zhang Guolei Xiang Wei He Prof. Xun Wang 《Angewandte Chemie (International ed. in English)》2014,53(2):429-433
Metal–organic frameworks (MOFs) have demonstrated great potentials in a variety of important applications. To enhance the inherent properties and endow materials with multifunctionality, the rational design and synthesis of MOFs with nanoscale porosity and hollow feature is highly desired and remains a great challenge. In this work, the formation of a series of well‐defined MOF (MOF‐5, FeII‐MOF‐5, FeIII‐MOF‐5) hollow nanocages by a facile solvothermal method, without any additional supporting template is reported. A surface‐energy‐driven mechanism may be responsible for the formation of hollow nanocages. The addition of pre‐synthesized poly(vinylpyrrolidone)‐ (PVP) capped noble‐metal nanoparticles into the synthetic system of MOF hollow nanocages yields the yolk–shell noble metal@MOF nanostructures. The present strategy to fabricate hollow and yolk–shell nanostructures is expected to open up exciting opportunities for developing a novel class of inorganic–organic hybrid functional nanomaterials. 相似文献