Showing papers by "Omar M. Yaghi published in 2012"
5,461 citations
TL;DR: Deconstructing the Crystal Structures of Metal Organic Frameworks and Related Materials into Their underlying Nets into Their Underlying Nets shows clear trends in how these materials are modified over time to form crystals.
Abstract: Deconstructing the Crystal Structures of Metal Organic Frameworks and Related Materials into Their Underlying Nets Michael O’Keeffe* and Omar M. Yaghi* Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287, United States Center for Reticular Chemistry, Center for Global Mentoring, Department of Chemistry and Biochemistry, University of California Los Angeles, 607 Charles E. Young Dr. East, Los Angeles, California 90095, United States Graduate School of EEWS, Korea Advanced Institute of Science and Technology, Daejeon, Korea
1,845 citations
TL;DR: A strategy to expand the pore aperture of metal-organic frameworks (MOFs) into a previously unattained size regime (>32 angstroms) is reported, as evidenced by their permanent porosity and high thermal stability (up to 300°C).
Abstract: We report a strategy to expand the pore aperture of metal-organic frameworks (MOFs) into a previously unattained size regime (>32 angstroms). Specifically, the systematic expansion of a well-known MOF structure, MOF-74, from its original link of one phenylene ring (I) to two, three, four, five, six, seven, nine, and eleven (II to XI, respectively), afforded an isoreticular series of MOF-74 structures (termed IRMOF-74-I to XI) with pore apertures ranging from 14 to 98 angstroms. All members of this series have noninterpenetrating structures and exhibit robust architectures, as evidenced by their permanent porosity and high thermal stability (up to 300°C). The pore apertures of an oligoethylene glycol–functionalized IRMOF-74-VII and IRMOF-74-IX are large enough for natural proteins to enter the pores.
1,637 citations
TL;DR: Two porphyrin-containing MOFs were metalated with iron(III) and copper(II) to yield the metalated analogues without losing their high surface area and chemical stability.
Abstract: Three new metal–organic frameworks [MOF-525, Zr6O4(OH)4(TCPP-H2)3; MOF-535, Zr6O4(OH)4(XF)3; MOF-545, Zr6O8(H2O)8(TCPP-H2)2, where porphyrin H4-TCPP-H2 = (C48H24O8N4) and cruciform H4-XF = (C42O8H22)] based on two new topologies, ftw and csq, have been synthesized and structurally characterized. MOF-525 and -535 are composed of Zr6O4(OH)4 cuboctahedral units linked by either porphyrin (MOF-525) or cruciform (MOF-535). Another zirconium-containing unit, Zr6O8(H2O)8, is linked by porphyrin to give the MOF-545 structure. The structure of MOF-525 was obtained by analysis of powder X-ray diffraction data. The structures of MOF-535 and -545 were resolved from synchrotron single-crystal data. MOF-525, -535, and -545 have Brunauer–Emmett–Teller surface areas of 2620, 1120, and 2260 m2/g, respectively. In addition to their large surface areas, both porphyrin-containing MOFs are exceptionally chemically stable, maintaining their structures under aqueous and organic conditions. MOF-525 and -545 were metalated with i...
705 citations
TL;DR: Mohamad Hmadeh et al. as discussed by the authors have proposed a method to improve the performance of nanotube research through mentoring, which has been shown to yield promising results in the field of Reticular Chemistry.
Abstract: Mohamad Hmadeh,†,‡ Zheng Lu,†,‡ Zheng Liu, Felipe Gandara,†,‡ Hiroyasu Furukawa,†,‡ Shun Wan,†,‡ Veronica Augustyn, Rui Chang, Lei Liao,‡ Fei Zhou, Emilie Perre, Vidvuds Ozolins, Kazu Suenaga, Xiangfeng Duan,‡ Bruce Dunn, Yasuaki Yamamto, Osamu Terasaki, and Omar M. Yaghi*,†,‡,#,¶ †Center for Reticular Chemistry, Center for Global Mentoring, ‡Department of Chemistry and Biochemistry, and Department of Materials Science and Engineering, University of California, Los Angeles, California 90095, United States Nanotube Research Center, AIST, Tsukuba 305-8565, Japan SMBU, JEOL Ltd., Akishima, Tokyo 196-8558, Japan Department of Materials and Environmental Chemistry and EXSELENT, Stockholm University, Stockholm, Sweden Graduate School of EEWS (WCU), Korea
512 citations
TL;DR: A new family of porous crystals was prepared by combining 1H-1,2,3-triazole and divalent metal ions to give six isostructural metal-Triazolates (termed MET-1 to 6), which have permanent porosity and display surface areas as high as some of the most porous zeolites, with one member of this family exhibiting significant electrical conductivity.
Abstract: A new family of porous crys- tals was prepared by combining 1H- 1,2,3-triazole and divalent metal ions (Mg, Mn, Fe, Co, Cu, and Zn) to give six isostructural metal-triazolates (termed MET-1 to 6). These materials are prepared as microcrystalline pow- ders, which give intense X-ray diffrac- tion lines. Without previous knowledge of the expected structure, it was possi- ble to apply the newly developed charge-flipping method to solve the complex crystal structure of METs: all the metal ions are octahedrally coordi- nated to the nitrogen atoms of triazo- late such that five metal centers are joined through bridging triazolate ions to form super-tetrahedral units that lie at the vertexes of a diamond-type structure. The variation in the size of metal ions across the series provides for precise control of pore apertures to a fraction of an Angstrom in the range 4.5 to 6.1 �. MET frameworks have permanent porosity and display surface areas as high as some of the most porous zeolites, with one member of this family, MET-3, exhibiting signifi- cant electrical conductivity.
225 citations
TL;DR: In this paper, five metal-organic frameworks (MOFs, termed MOF-324, 325, 326 and IRMOF-61 and 62) were characterized by single-crystal X-ray diffraction, and their low-pressure and high-pressure hydrogen uptake properties were investigated.
Abstract: Five new metal–organic frameworks (MOFs, termed MOF-324, 325, 326 and IRMOF-61 and 62) of either short linkers (pyrazolecarboxylate and pyrazaboledicarboxylate) or long and thin alkyne functionalities (ethynyldibenzoate and butadiynedibenzoate) were prepared to examine their impact on hydrogen storage in MOFs. These compounds were characterized by single-crystal X-ray diffraction, and their low-pressure and high-pressure hydrogen uptake properties were investigated. In particular, volumetric excess H2 uptake by MOF-324 and IRMOF-62 outperforms MOF-177 up to 30 bar. Inelastic neutron-scattering studies for MOF-324 also revealed strong interactions between the organic links and hydrogen, in contrast to MOF-5 where the interactions between the Zn4O unit and hydrogen are the strongest. These data also show that smaller pores and polarized linkers in MOFs are indeed advantageous for hydrogen storage.
187 citations
TL;DR: In this article, the dominant nuclear spin-lattice relaxation (T1) mechanism for ZIF-8 in air arises from atmospheric paramagnetic molecular oxygen, which interacts primarily with the imidazolate ring rather than the methyl substituent.
Abstract: NMR relaxation studies and spectroscopic measurements of zeolitic imidazolate framework-8 (ZIF-8) are reported. The dominant nuclear spin–lattice relaxation (T1) mechanism for ZIF-8 in air arises from atmospheric paramagnetic molecular oxygen. The 13C T1 measurements indicate that the oxygen interacts primarily with the imidazolate ring rather than the methyl substituent. Similar relaxation behavior was also observed in a ZIF with an unsubstituted ring, ZIF-4. Single-crystal X-ray diffraction was used to provide data for the study of the thermal ellipsoids of ZIF-8 at variable temperatures from 100 to 298 K, which further confirmed the rigid nature of this ZIF framework. These results highlight a rigid ZIF framework and are in contrast with dynamic metal–organic frameworks based on benzenedicarboxylate linking groups, for which the relaxation reflects the dynamics of the benzenedicarboxylate moiety.
147 citations
TL;DR: In synthetic materials, specifically in metal–organic frameworks (MOFs), many advantageous properties also arise when MOFs are interpenetrated, such as selective guest capture, stepwise gas adsorption, enhanced framework robustness, photoluminescence control, and guest-responsive porosity.
Abstract: Interpenetration is known for the structures of many minerals and ice; most notably for ice, it exists in doubly interpenetrating (VI, VII, and VIII) and non-interpenetrating (Ih) forms with the latter being porous and having nearly half of the density of the former. In synthetic materials, specifically in metal–organic frameworks (MOFs), interpenetration is generally considered undesirable because it reduces porosity. However, on the contrary, many advantageous properties also arise when MOFs are interpenetrated, such as selective guest capture, stepwise gas adsorption, enhanced framework robustness, photoluminescence control, and guest-responsive porosity. Therefore, various strategies have been suggested to control interpenetration during synthesis. However, once these extended network materials are prepared as interpenetrating or non-interpenetrating structures, the degree of interpenetration generally remains unchanged, because numerous chemical bonds must be broken and subsequently reformed in a very concerted way during the process unlike some interlocked coordination compounds in solution (Figure 1a).
138 citations
TL;DR: In this article, the effect of topology on gas adsorption in ZIFs was studied and it was shown that the topologies with the smaller pores have larger adsorptions than their counterparts (ZIF-7 and 93, respectively) at low pressures.
Abstract: We report CO2 adsorption data for four zeolitic imidazolate frameworks (ZIFs) to 55 bar, namely ZIF-7, ZIF-11, ZIF-93, and ZIF-94. Modification of synthetic conditions allows access to different topologies with the same metal ion and organic link: ZIF-7 (ZIF-94) having sod topology and ZIF-11 (ZIF-93) having the rho topology. The varying topology, with fixed metal ion and imidazolate functionality, makes these systems ideal for studying the effect of topology on gas adsorption in ZIFs. The experiments show that the topologies with the smaller pores (ZIF-7 and 94) have larger adsorptions than their counterparts (ZIF-11 and 93, respectively) at low pressures (<1 bar); however, the reverse is true at higher pressures where the larger-pore structures have significantly higher adsorption. Molecular modeling and heat of adsorption measurements indicate that while the binding potential wells for the smaller-pore structures are deeper than those of the larger-pore structures, they are relatively narrow and cannot...
123 citations
TL;DR: A copper-coordinatedpseudorotaxanate which reacts with zinc nitrate to form threefold interpenetrated networks retains most of its solution-state chemistry, including its ability to undergo electronic switching of some of the copper(I) ions under redox control.
Abstract: MOFs on the move: A copper-coordinated [2]pseudorotaxanate which reacts with zinc nitrate to form threefold interpenetrated networks retains most of its solution-state chemistry, including its ability to undergo electronic switching of some of the copper(I) ions under redox control.
TL;DR: This work studies the H2 binding energy to 48 compounds based on various metalated analogues of five common linkers for covalent organic frameworks (COFs) and finds that the new COF-301-PdCl2 reaches 60 g total H2/L at 100 bar, which is 1.5 times the DOE 2015 target and close to the ultimate target of 70 g/L.
Abstract: Physisorption in porous materials is a promising approach for meeting H2 storage requirements for the transportation industry, because it is both fully reversible and fast at mild conditions. However, most current candidates lead to H2 binding energies that are too weak (leading to volumetric capacity at 298 K of <10 g/L compared to the DOE 2015 Target of 40 g/L). Using accurate quantum mechanical (QM) methods, we studied the H2 binding energy to 48 compounds based on various metalated analogues of five common linkers for covalent organic frameworks (COFs). Considering the first transition row metals (Sc though Cu) plus Pd and Pt, we find that the new COF-301-PdCl2 reaches 60 g total H2/L at 100 bar, which is 1.5 times the DOE 2015 target of 40 g/L and close to the ultimate (2050) target of 70 g/L. The best current materials, MOF-200 and MOF-177, are predicted to store 7.6 g/L (0.54 wt % excess) and 9.6 g/L (0.87 wt % excess), respectively, at 298 K and 100 bar compared with 60 g/L (4.2 wt % excess) for C...
TL;DR: Three metal-organic complex arrays with a specific sequence of metal centers as well as that of amino acid units were synthesized, exhibiting a gelation capability dependent on the location of the metal complexes in the arrays.
Abstract: Three metal–organic complex arrays (MOCAs) with a specific sequence of metal centers as well as that of amino acid units were synthesized. These MOCAs are also isomers exhibiting a gelation capability dependent on the location of the metal complexes in the arrays.
Patent•
12 Oct 2012TL;DR: In this article, the disclosure relates to metal organic frameworks or isoreticular metal organic framework, methods of production thereof, and methods of use thereof, as well as their applications.
Abstract: The disclosure relates to metal organic frameworks or isoreticular metal organic frameworks, methods of production thereof, and methods of use thereof.
Patent•
20 Jan 2012TL;DR: In this article, the metal-triazolate frameworks, methods of use thereof, and devices comprising the frameworks thereof are described, as well as a discussion of their application in the context of medical applications.
Abstract: The disclosure provides for novel metal-triazolate frameworks, methods of use thereof, and devices comprising the frameworks thereof.
Patent•
01 Feb 2012TL;DR: In this paper, metal catecholate frameworks, and methods of use thereof, including gas separation, gas storage, catalysis, tunable conductors, supercapacitors, and sensors, are discussed.
Abstract: The disclosure provides for metal catecholate frameworks, and methods of use thereof, including gas separation, gas storage, catalysis, tunable conductors, supercapacitors, and sensors.
Patent•
12 Oct 2012
TL;DR: Invention concerne des reseaux metal-organiques ou des reaux metalorganiques isoreticulaires, des procedes permettant de les fabriquer et des procedures permettent de les utiliser as discussed by the authors.
Abstract: L'invention concerne des reseaux metal-organiques ou des reseaux metal-organiques isoreticulaires, des procedes permettant de les fabriquer et des procedes permettant de les utiliser.
Patent•
01 Feb 2012
TL;DR: The presente invention concerne des structures en catecholate metallique and leurs procedes d'utilisation, notamment la separation des gaz, le stockage de gaz and la catalyse, des conducteurs accordables, des supercondensateurs and des capteurs.
Abstract: La presente invention concerne des structures en catecholate metallique et leurs procedes d'utilisation, notamment la separation des gaz, le stockage de gaz, la catalyse, des conducteurs accordables, des supercondensateurs et des capteurs