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1.
Cristina Mottillo Prof. Tomislav Friščić 《Angewandte Chemie (International ed. in English)》2014,53(29):7471-7474
Zeolitic imidazolate frameworks of zinc, cobalt, and cadmium, including the framework ZIF‐8 commercially sold as Basolite Z1200, exhibit surprising sensitivity to carbon dioxide under mild conditions. The frameworks chemically react with CO2 in the presence of moisture or liquid water to form carbonates. This effect, which has been previously not reported in metal–organic framework chemistry, provides an explanation for conflicting reports on ZIF‐8 stability to water and is of outstanding significance for evaluating the potential applications of metal–organic frameworks, especially for CO2 sequestration. 相似文献
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Selective Capture of Carbon Dioxide under Humid Conditions by Hydrophobic Chabazite‐Type Zeolitic Imidazolate Frameworks 下载免费PDF全文
Nhung T. T. Nguyen Dr. Hiroyasu Furukawa Dr. Felipe Gándara Dr. Hoang T. Nguyen Kyle E. Cordova Prof. Omar M. Yaghi 《Angewandte Chemie (International ed. in English)》2014,53(40):10645-10648
Hydrophobic zeolitic imidazolate frameworks (ZIFs) with the chabazite ( CHA ) topology are synthesized by incorporating two distinct imidazolate links. Zn(2‐mIm)0.86(bbIm)1.14 (ZIF‐300), Zn(2‐mIm)0.94(cbIm)1.06 (ZIF‐301), and Zn(2‐mIm)0.67(mbIm)1.33 (ZIF‐302), where 2‐mIm=2‐methylimidazolate, bbIm=5(6)‐bromobenzimidazolate, cbIm=5(6)‐chlorobenzimidazolate, and mbIm=5(6)‐methylbenzimidazolate, were prepared by reacting zinc nitrate tetrahydrate and 2‐mIm with the respective bIm link in a mixture of N,N‐dimethylformamide (DMF) and water. Their structures were determined by single‐crystal X‐ray diffraction and their permanent porosity shown. All of these structures are hydrophobic as confirmed by water adsorption isotherms. All three ZIFs are equally effective at the dynamic separation of CO2 from N2 under both dry and humid conditions without any loss of performance over three cycles and can be regenerated simply by using a N2 flow at ambient temperature. 相似文献
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Jian Zhang Dr. Tao Wu Cong Zhou Shumei Chen Dr. Pingyun Feng Prof. Dr. Xianhui Bu Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(14):2542-2545
B‐hive? A family of crystalline materials analogous to porous AlPO4 but based on boron imidazolate frameworks (BIFs) can be formed by the crosslinking of various presynthesized boron imidazolates with monovalent cations (Li+ and Cu+, see picture). This synthetic method is capable of generating a large variety of open frameworks, ranging from the four‐connected zeolitic sodalite type to the three‐connected chiral (10,3)‐a type.
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Photochemical Reduction of Low Concentrations of CO2 in a Porous Coordination Polymer with a Ruthenium(II)–CO Complex 下载免费PDF全文
Dr. Takashi Kajiwara Machiko Fujii Dr. Masahiko Tsujimoto Dr. Katsuaki Kobayashi Dr. Masakazu Higuchi Prof. Dr. Koji Tanaka Prof. Dr. Susumu Kitagawa 《Angewandte Chemie (International ed. in English)》2016,55(8):2697-2700
Direct use of low pressures of CO2 as a C1 source without concentration from gas mixtures is of great interest from an energy‐saving viewpoint. Porous heterogeneous catalysts containing both adsorption and catalytically active sites are promising candidates for such applications. Here, we report a porous coordination polymer (PCP)‐based catalyst, PCP‐RuII composite, bearing a RuII‐CO complex active for CO2 reduction. The PCP‐RuII composite showed improved CO2 adsorption behavior at ambient temperature. In the photochemical reduction of CO2 the PCP‐RuII composite produced CO, HCOOH, and H2. Catalytic activity was comparable with the corresponding homogeneous RuII catalyst and ranks among the highest of known PCP‐based catalysts. Furthermore, catalytic activity was maintained even under a 5 % CO2/Ar gas mixture, revealing a synergistic effect between the adsorption and catalytically active sites within the PCP‐RuII composite. 相似文献
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Javier Pérez‐Pellitero Dr. Hedi Amrouche Flor R. Siperstein Dr. Gerhard Pirngruber Dr. Carlos Nieto‐Draghi Dr. Gérald Chaplais Dr. Angélique Simon‐Masseron Dr. Delphine Bazer‐Bachi Dr. David Peralta Nicolas Bats Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(5):1560-1571
Experimental measurements and molecular simulations were conducted for two zeolitic imidazolate frameworks, ZIF‐8 and ZIF‐76. The transferability of the force field was tested by comparing molecular simulation results of gas adsorption with experimental data available in the literature for other ZIF materials (ZIF‐69). Owing to the good agreement observed between simulation and experimental data, the simulation results can be used to identify preferential adsorption sites, which are located close to the organic linkers. Topological mapping of the potential‐energy surfaces makes it possible to relate the preferential adsorption sites, Henry constant, and isosteric heats of adsorption at zero coverage to the nature of the host–guest interactions and the chemical nature of the organic linker. The role played by the topology of the solid and the organic linkers, instead of the metal sites, upon gas adsorption on zeolite‐like metal–organic frameworks is discussed. 相似文献
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Dr. Yiyin Mao Danke Chen Pan Hu Dr. Yi Guo Dr. Yulong Ying Dr. Wen Ying Prof. Dr. Xinsheng Peng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(43):15127-15132
Hierarchical porous materials are promising for catalyst, separation and sorption applications. A ligand‐assisted etching process is developed for template‐free synthesis of hierarchical mesoporous MOFs as single crystals and well‐intergrown membranes at 40 °C. At 223 K, the hierarchical porous structures significantly improve the CO2 capture capacity of HKUST‐1 by more than 44 % at pressures up to 20 kPa and 13 % at 100 kPa. Even at 323 K, the enhancement of CO2 uptake is above 25 % at pressures up to 20 kPa and 7 % at 100 kPa. The mesoporous structures not only enhance the CO2 uptake capacity but also improve the diffusion and mass transportation of CO2. Similarly, well‐intergrown mesoporous HKUST‐1 membranes are synthesized, which hold the potential for film‐like porous devices. Mesoporous MOF‐5 crystals are also obtained by a similar ligand‐assisted etching process. This may provide a facile way to prepare hierarchical porous MOF single crystals and membranes for wide‐ranging applications. 相似文献
7.
Ionic Liquids Supported on Metal‐Organic Frameworks: Remarkable Adsorbents for Adsorptive Desulfurization 下载免费PDF全文
Dr. Nazmul Abedin Khan Zubair Hasan Prof. Dr. Sung Hwa Jhung 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(2):376-380
Acidic ionic‐liquids (IL) supported on metal–organic frameworks (MOFs) have been shown to be beneficial for adsorptive desulfurization. A remarkable improvement in the adsorption capacity (ca. 71%) was observed in for ILs supported on MIL‐101 compared with virgin MIL‐101. The improved adsorptive performance might be explained by the acid–base interactions between the acidic ionic liquid and basic benzothiophene (BT). Moreover, from this study, it can be suggested that porous MOFs, supported with ionic liquids, may introduce a new class of highly porous adsorbents for the efficient adsorption of various compounds. 相似文献
8.
Back Cover: Selective Capture of Carbon Dioxide under Humid Conditions by Hydrophobic Chabazite‐Type Zeolitic Imidazolate Frameworks (Angew. Chem. Int. Ed. 40/2014) 下载免费PDF全文
Nhung T. T. Nguyen Dr. Hiroyasu Furukawa Dr. Felipe Gándara Dr. Hoang T. Nguyen Kyle E. Cordova Prof. Omar M. Yaghi 《Angewandte Chemie (International ed. in English)》2014,53(40):10828-10828
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The electrochemical reduction of CO2 holds great promise for lowering the concentration of CO2 in the Earth′s atmosphere. However, several challenges have hindered the commercialization of this technology, including energy efficiency, the solubility of CO2 in the aqueous phase, and electrode stability. In this Minireview, we highlight and summarize the main advantages and limitations that metal–organic frameworks (MOFs) may offer in this field of research, either when used directly as electrocatalysts or when used as catalyst precursors. 相似文献
11.
Modelling a Linker Mix‐and‐Match Approach for Controlling the Optical Excitation Gaps and Band Alignment of Zeolitic Imidazolate Frameworks 下载免费PDF全文
Dr. Ricardo Grau‐Crespo Alex Aziz Angus W. Collins Dr. Rachel Crespo‐Otero Dr. Norge C. Hernández Dr. L. Marleny Rodriguez‐Albelo Dr. A. Rabdel Ruiz‐Salvador Prof. Dr. Sofia Calero Dr. Said Hamad 《Angewandte Chemie (International ed. in English)》2016,55(52):16012-16016
Tuning the electronic structure of metal–organic frameworks is the key to extending their functionality to the photocatalytic conversion of absorbed gases. Herein we discuss how the band edge positions in zeolitic imidazolate frameworks (ZIFs) can be tuned by mixing different imidazole‐based linkers within the same structure. We present the band alignment for a number of known and hypothetical Zn‐based ZIFs with respect to the vacuum level. Structures with a single type of linker exhibit relatively wide band gaps; however, by mixing linkers of a low‐lying conduction edge with linkers of a high‐lying valence edge, we can predict materials with ideal band positions for visible‐light water splitting and CO2 reduction photocatalysis. By introducing copper in the tetrahedral position of the mixed‐linker ZIFs, it would be possible to increase both photo‐absorption and the electron–hole recombination times. 相似文献
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Yanqiang Zhang Dr. Suojiang Zhang Prof. Dr. Xingmei Lu Dr. Qing Zhou Dr. Wei Fan XiangPing Zhang Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(12):3003-3011
CO 2 is locked up : Dual amino‐functionalised phosphonium ionic liquids (ILs; see figure) have been prepared. The ILs have excellent thermal properties, such as low glass transition temperatures and high thermal decomposition temperatures. The supported CO2 absorption of four of the ILs on porous SiO2 was found to approach one mol CO2 per mol IL, a factor of two greater than that reported before.
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Frontispiece: Modelling a Linker Mix‐and‐Match Approach for Controlling the Optical Excitation Gaps and Band Alignment of Zeolitic Imidazolate Frameworks 下载免费PDF全文
Dr. Ricardo Grau‐Crespo Alex Aziz Angus W. Collins Dr. Rachel Crespo‐Otero Dr. Norge C. Hernández Dr. L. Marleny Rodriguez‐Albelo Dr. A. Rabdel Ruiz‐Salvador Prof. Dr. Sofia Calero Dr. Said Hamad 《Angewandte Chemie (International ed. in English)》2016,55(52)
14.
MoP Nanoparticles Supported on Indium‐Doped Porous Carbon: Outstanding Catalysts for Highly Efficient CO2 Electroreduction 下载免费PDF全文
Xiaofu Sun Lu Lu Dr. Qinggong Zhu Dr. Congyi Wu Dexin Yang Chunjun Chen Prof. Dr. Buxing Han 《Angewandte Chemie (International ed. in English)》2018,57(9):2427-2431
Electrochemical reduction of CO2 into value‐added product is an interesting area. MoP nanoparticles supported on porous carbon were synthesized using metal–organic frameworks as the carbon precursor, and initial work on CO2 electroreduction using the MoP‐based catalyst were carried out. It was discovered that MoP nanoparticles supported on In‐doped porous carbon had outstanding performance for CO2 reduction to formic acid. The Faradaic efficiency and current density could reach 96.5 % and 43.8 mA cm?2, respectively, when using ionic liquid 1‐butyl‐3‐methylimidazolium hexafluorophosphate as the supporting electrolyte. The current density is higher than those reported up to date with very high Faradaic efficiency. The MoP nanoparticles and the doped In2O3 cooperated very well in catalyzing the CO2 electroreduction. 相似文献
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Qing Zhang Zhengming Wu Yuan Lv Yali Li Yajing Zhao Rui Zhang Yushuang Xiao Xiaofei Shi Danrui Zhang Rui Hua Jianlin Yao Jun Guo Rong Huang Yi Cui Zhenhui Kang Subhadip Goswami Lee Robison Kepeng Song Xinghua Li Yu Han Lifeng Chi Omar K. Farha Guang Lu 《Angewandte Chemie (International ed. in English)》2019,58(4):1123-1128
Processing metal–organic frameworks (MOFs) as films with controllable thickness on a substrate is increasingly crucial for many applications to realize function integration and performance optimization. Herein, we report a facile cathodic deposition process that enables the large‐area preparation of uniform films of zeolitic imidazolate frameworks (ZIF‐8, ZIF‐71, and ZIF‐67) with highly tunable thickness ranging from approximately 24 nm to hundreds of nanometers. Importantly, this oxygen‐reduction‐triggered cathodic deposition does not lead to the plating of reduced metals (Zn and Co). It is also operable cost‐effectively in the absence of supporting electrolyte and facilitates the construction of well‐defined sub‐micrometer‐sized heterogeneous structures within ZIF films. 相似文献
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Dengrong Sun Dr. Yanghe Fu Wenjun Liu Lin Ye Dengke Wang Lin Yang Prof. Dr. Xianzhi Fu Prof. Dr. Zhaohui Li 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(42):14279-14285
Metal–organic framework (MOF) NH2‐Uio‐66(Zr) exhibits photocatalytic activity for CO2 reduction in the presence of triethanolamine as sacrificial agent under visible‐light irradiation. Photoinduced electron transfer from the excited 2‐aminoterephthalate (ATA) to Zr oxo clusters in NH2‐Uio‐66(Zr) was for the first time revealed by photoluminescence studies. Generation of ZrIII and its involvement in photocatalytic CO2 reduction was confirmed by ESR analysis. Moreover, NH2‐Uio‐66(Zr) with mixed ATA and 2,5‐diaminoterephthalate (DTA) ligands was prepared and shown to exhibit higher performance for photocatalytic CO2 reduction due to its enhanced light adsorption and increased adsorption of CO2. This study provides a better understanding of photocatalytic CO2 reduction over MOF‐based photocatalysts and also demonstrates the great potential of using MOFs as highly stable, molecularly tunable, and recyclable photocatalysts in CO2 reduction. 相似文献
18.
Pengyuan Wang Dr. Jia Liu Chuanfang Liu Bin Zheng Prof. Dr. Xiaoqin Zou Prof. Dr. Mingjun Jia Prof. Dr. Guangshan Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(46):16613-16620
It is very interesting and also a big challenge to encapsulate metal clusters within microporous solids to expand their application diversity. For this target, herein, we present an electrochemical synthesis strategy for the encapsulation of noble metals (Au, Pd, Pt) within ZIF‐8 cavities. In this method, metal precursors of AuCl42?, PtCl62?, and PdCl42? are introduced into ZIF‐8 crystals during the concurrent crystallization of ZIF‐8 at the anode. As a consequence, very small metal clusters with sizes around 1.2 nm are obtained within ZIF‐8 crystals after hydrogen reduction; these clusters exhibit high thermal stability, as evident from the good maintenance of their original sizes after a high‐temperature test. The catalytic properties of the encapsulated metal clusters within ZIF‐8 are evaluated for CO oxidations. Because of the small pore window of ZIF‐8 (0.34 nm) and the confinement effect of small pores, about 80 % of the metal clusters (fractions of 0.74, 0.77, and 0.75 for Au, Pt, and Pd in ZIF‐8, respectively) retain their catalytic activity after exposure to the organosulfur poison thiophene (0.46 nm), which is in contrast to their counterparts (fractions of 0.22, 0.25, and 0.20 for Au, Pt, and Pd on the SiO2 support). The excellent performances of metal clusters encapsulated within ZIF‐8 crystals give new opportunities for catalytic reactions. 相似文献
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Dr. Suvendu Sekhar Mondal Dr. Asamanjoy Bhunia Ahmed G. Attallah Dr. Philipp R. Matthes Alexandra Kelling Prof. Uwe Schilde Prof. Klaus Müller‐Buschbaum Prof. Reinhard Krause‐Rehberg Prof. Christoph Janiak Prof. Hans‐Jürgen Holdt 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(20):6905-6913
An extended member of the isoreticular family of metal–imidazolate framework structures, IFP‐6 (IFP=imidazolate framework Potsdam), based on cadmium metal and an in situ functionalized 2‐methylimidazolate‐4‐amide‐5‐imidate linker is reported. A porous 3D framework with 1D hexagonal channels with accessible pore windows of 0.52 nm has been synthesized by using an ionic liquid (IL) linker precursor. IFP‐6 shows significant gas uptake capacity only for CO2 and CH4 at elevated pressure, whereas it does not adsorb N2, H2, and CH4 under atmospheric conditions. IFP‐6 is assumed to deteriorate at the outside of the material during the activation process. This closing of the metal–organic framework (MOF) pores is proven by positron annihilation lifetime spectroscopy (PALS), which revealed inherent crystal defects. PALS results support the conservation of the inner pores of IFP‐6. IFP‐6 has also been successfully loaded with luminescent trivalent lanthanide ions (LnIII=Tb, Eu, and Sm) in a bottom‐up one‐pot reaction through the in situ generation of the linker ligand and in situ incorporation of photoluminescent Ln ions into the constituting network. The results of photoluminescence investigations and powder XRD provide evidence that the Ln ions are not doped as connectivity centers into the frameworks, but are instead located within the pores of the MOFs. Under UV light irradiation, Tb@IFP‐6 and Eu@IFP‐6 (λexc=365 nm) exhibit observable emission changes to a greenish and reddish color, respectively, as a result of strong Ln 4 f emissions. 相似文献
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