Crystal Design & MOF Synthesis

While there are many serendipitous discoveries in MOF chemistry, rational top-down design and assembly with molecular-level precision is crucial for the efficient preparation of novel, targeted MOF materials. The expansion of topology-directed crystal engineering, referred to as reticular chemistry, permits the geometry-guided architectural arrangement of crystalline frameworks (e.g. MOFs) by linking pre-selected molecular building blocks (MBBs). The applications of topology-directed crystal engineering can be divided into two parts: the discovery of novel materials and the execution of isoreticular chemistry. The former generally aims to design a blueprint net as a target, and then assemble pre-selected organic and inorganic MBBs to achieve the desired topology. The latter, on the other hand, aims to fine tune and functionalize the MBBs of a preexisting MOF to achieve structural analogues with unique and desirable properties. While their modular nature allows for designing functional MOFs using de novo synthesis, there are conditions where desired functionality is very challenging to introduce using direct synthetic methods. In these cases, we have developed post-synthesis crystal engineering methods to access preferred functionalities. These techniques include methods for functionalizing MOF nodes, i.e., solvent-assisted ligand incorporation (SALI) and atomic layer deposition in MOFs (AIM) as well as solvent-assisted linker exchange (SALE), a method to replace structural linkers. We continue to pioneer novel synthetic methodologies which allow us to access atomically precise MOFs with novel topological properties.

Selected Reviews

  • “Reticular Chemistry in the Rational Synthesis of Functional Zirconium Cluster-Based MOFs” Chen, Z.; Hanna, S. L.; Redfern, L. R.; Alezi, D.; Islamoglu, T.; Farha, O. K. Coord. Chem. Rev. 2019, 386, 32-49.

Selected Research Articles

  • “Ligand-Directed Reticular Synthesis of Catalytically Active Missing Zirconium-Based Metal–Organic Frameworks” Chen, Z.; Li, P.; Wang, X.; Otake, K.-i.; Zhang, X.; Robison, L.; Atilgan, A.; Islamoglu, T.; Hall, M. G.; Peterson, G. W.; Stoddart, J. F.; Farha, O. K. Am. Chem. Soc. 2019, 141, 12229-12235.
  • “Topology and Porosity Control of Metal-Organic Frameworks through Linker Functionalization” Lyu, J. F.; Zhang, X.; Otake, K.; Wang, X. J.; Li, P.; Li, Z. Y.; Chen, Z. J.; Zhang, Y. Y.; Wasson, M. C.; Yang, Y.; Bai, P.; Guo, X. H.; Islamoglu, T.; Farha, O. K. Sci. 2019, 10, 1186-1192. DOI:10.1039/C8SC04220A
  • “Bottom-up construction of a superstructure in a porous uranium-organic crystal” Li, P.; Vermeulen, N. A.; Malliakas, C. D.; Gómez-Gualdrón, D. A.; Howarth, A. J.; Mehdi, B. L.; Dohnalkova, A.; Browning, N. D.; O’Keeffe, M.; Farha, O. K., Science 2017,356, 624-627. org/10.1126/science.aam7851
  • “Solvent-assisted linker exchange enabled preparation of cerium-based metal-organic frameworks constructed from redox active linkers” Son, F.; Atilgan, A.; Idrees, K.; Islamoglu, T.; Farha, O. K.; under review

    Detoxification of Chemical Warfare Agents

         Organophosphonate-based Nerve Agents

    Chemical warfare agents containing phosphonate ester bonds are among the most toxic chemicals ever created. Solutions are needed for immediate personal protection (for example, the filtration and catalytic destruction of airborne versions of agents), bulk destruction of chemical weapon stockpiles, protection (via coating) of clothing, equipment and buildings, and containment of agent spills. The selective, hydrolytic cleavage of the P—F bond of organophosphonate based nerve agents is effective for chemical detoxification of these agents. P—F bond cleavage with cationic Lewis acids is particularly promising as phosphonate ester hydrolysis can be accelerated by polarizing the P═O bond.

    In the Farha group, we design/identify metal-organic frameworks (MOFs) that can effectively catalyze the important reactions shown above. We fine tune chemical (i.e. metal, functional groups etc.) and/or physical properties (node connectivity, topology, pore size, particle size etc.) of the MOFs and monitor the reactivity towards a nerve agent simulant, DMNP, in our lab, and towards actual nerve agents such as VX and GD in collaboration with US. Army Research labs. We have developed materials that show almost instantaneous hydrolysis of these toxic chemicals using catalytic amounts of MOFs.

    Selected Reviews

    • “Metal-Organic Frameworks against Toxic Chemicals” Islamoglu, T.; Chen, Z.; Wasson, M.C.; Cassandra, T.B.; Kirlikovali, K.; Afrin, U.; Mian, M. R.; Farha. O. K.; under review
    • “Zirconium-Based Metal–Organic Frameworks for the Catalytic Hydrolysis of Organophosphorus Nerve Agents” Kirlikovali, K., Chen, Z., Islamoglu, T., Hupp, J. T., Farha. O. K.; under review
    • “Metal-organic frameworks for the removal of toxic industrial chemicals and chemical warfare agents.” Bobbitt, N. S.; Mendonca, M. L.; Howarth, A. J.; Islamoglu, T.; Hupp, J. T.; Farha, O. K.; Snurr, R. Q.;  Soc. Rev.; 2017, 46, pp.3357-3385.

    Selected Research Articles

    • “Integration of Metal–Organic Frameworks on Protective Layers for Destruction of Nerve Agents under Relevant Conditions” Chen, Z.; Ma, K.; Mahle, J. J.; Wang, H.; Syed, Z. H.; Atilgan, A.; Chen, Y.; Xin, J. H.; Islamoglu, T.; Peterson, G. W.; Farha, O. K., Am. Chem. Soc. 2019, 141, (51), 20016-20021.
    • “Scalable and Template-Free Aqueous Synthesis of Zirconium-Based Metal–Organic Framework Coating on Textile Fiber.” Ma, K.; Islamoglu, T.; Chen, Z.; Li, P.; Wasson, M.C.; Chen, Y.; Wang, Y.; Peterson, G.W.; Xin, J.H.; Farha, O.K.; Am. Chem. Soc.2019141, pp. 15626-15633.
    • “Presence versus Proximity: The Role of Pendant Amines in the Catalytic Hydrolysis of a Nerve Agent Simulant.” Islamoglu, T.; Ortuño, M. A.; Proussaloglou, E.; Howarth, A. J.; Vermeulen, N. A.; Atilgan, A.; Asiri, A. M.; Cramer, C. J.; Farha, O. K.;  Chem. Int. Ed.; 2018, 130, pp. 1967-1971.
    •  “Cerium(IV) vs Zirconium(IV) Based Metal-Organic Frameworks for Detoxification of a Nerve Agent.” Islamoglu, T.; Atilgan, A.; Moon, S. Y.; Peterson, G. W.; DeCoste, J. B.; Hall, M.; Hupp, J. T.; Farha, O. K., Chem. Mater. 2017, 29, (7), 2672-2675.


           Detoxification of HD and its simulants

      The continued prevalence of chemical warfare agents (CWAs) as weapons of mass destruction (WMD) and in stockpile materials necessitates the development of materials capable of rapid detoxification of these chemicals.Among the commonly used CWAs, sulfur mustard (also known as mustard gas or HD) incapacitates its victims by causing painful blisters and irreversible tissue damage. We have found oxidation of HD to the nontoxic sulfoxide derivative is a viable detoxification pathway. The challenge of this oxidation occurs with over-oxidation to the sulfone derivative, which has similar toxic properties as the parent HD; therefore, the reaction must selectively yield the sulfoxide.

      In the Farha group, we have taken two approaches for the rapid, selective oxidation of HD: 1) using MOF linkers and ligands as photosensitizers to generate singlet oxygen from atmospheric oxygen upon LED irradiation and 2) installing soluble, but catalytically active polyoxometalates (POMs) in a MOF to activate hydrogen peroxide or atmospheric oxygen. At Northwestern, we test these materials using simulants, chemicals with similar properties as CWA but much less toxic; our collaborators have capabilities allowing them to test our materials against the real agents.

      Because the linkers and the installation of POMs leave the MOF node untouched, HD oxidation can be coupled with the decomposition of toxic organophosphate nerve agents, a reaction which occurs on the MOF nodes. We wish to continue developing new materials and composites to achieve the ultimate catalyst for CWA detoxification.

      Selected Research Articles

      •  “Restricting Polyoxometalate Movement within Metal-Organic Frameworks to Assess the Role of Residual Water in Catalytic Thioether Oxidation Using These Dynamic Composites” Buru, C. T.; Lyu, J.; Liu, J.; Farha, O. K. Frontiers in Materials 2019, 6, 152.
      • “Thermally Induced Migration of a Polyoxometalate within a Metal-Organic Framework and Its Catalytic Effects” Buru, C. T.; Platero-Prats, A. E.; Chica, D. G.; Kanatzidis, M. G.; Chapman, K. W.; Farha, O. K. J. Mater. Chem. A 2018, 6, 7389-7394. doi:10.1039/c8ta02562b
      •  “Postsynthetic Incorporation of a Singlet Oxygen Photosensitizer in a Metal–Organic Framework for Fast and Selective Oxidative Detoxification of Sulfur Mustard” Howarth, A. J.; Buru, C. T.; Liu, Y.; Ploskonka, A. M.; Hartlieb, K. J.; McEntee, M.; Mahle, J. J.; Buchanan, J. H.; Durke, E. M.; Al-Juaid, S. S.; Stoddart, J. F.; DeCoste, J. B.; Hupp, J. T.; Farha, O. K., Chem. Eur. J. 2017, 23, 214-218.


        Enzyme Encapsulation

        One significant obstacle to using recombinant proteins for biocatalytic and biotechnological applications is the production costs of enzymes and coenzymes in addition to high separation and isolation costs, intolerance to toxic products, and poor thermal and long-term stability. To address these challenges, efficient immobilization strategies based on biocompatible carriers are needed to realize the use of enzymes and regeneration of coenzymes for large-scale industrial production of fine chemicals, drug delivery and biocatalytic applications. The effective use of hybrid materials requires a delicate balance among structure, biocompatibility, and stability. The specific aims in Farha group under this research topic include:

        1) Develop efficient de novo and post-modification immobilization strategies to prepare stable and biocompatible inorganic/organic/biological hybrid materials.

        2) Study the diffusion, accessibility, and reactivity of biomolecules confined in the nanospace of well-defined porous crystalline materials.

        3) Investigate the stability of the encapsulated enzymes and their ability to withstand pH changes, temperature swings and toxic intermediates formed during biocatalysis.  

        Selected Reviews

        • “Catalytic applications of enzymes encapsulated in metal-organic frameworks.” Drout, R.J.; Robison, L.; Farha, O.K.;  Coord. Chem. Rev.;2019381, pp. 151-160.

        • “Enzyme Encapsulation in Metal–organic Frameworks for Applications in Catalysis.” Majewski, M. B.; Howarth, A. J.; Li, P.; Wasielewski, M. R.; Hupp, J. T.; Farha, O. K., CrystEngComm 2017, 19, 4082-4091.

        Selected Research Articles

        • “Hierarchically Engineered Mesoporous Metal-Organic Frameworks toward Cell-free Immobilized Enzyme Systems.” Li, P.; Chen, Q.; Wang, T. C.; Vermeulen, N. A.; Mehdi, B. L.; Dohnalkova, A.; Browning, N. D.; Shen, D.; Anderson, R.; Gómez-Gualdrón, D. A.; Cetin, F. M.; Jagiello, J.; Asiri, A. M.; Stoddart, J. F.; Farha, O. K.; Chem; 2018, 4, pp. 1022–1034.
        • “DNA-Functionalized Metal-Organic Framework Nanoparticles for Intracellular Delivery of Proteins.” Wang, S.; Chen, Y.; Wang, S.; Li, P.; Mirkin, C.A.; Farha, O.K.;  Am. Chem. Soc.; 2019, 141, pp. 2215-2219.
        • “Acid-Resistant Mesoporous Metal–Organic Framework toward Oral Insulin Delivery: Protein Encapsulation, Protection, and Release.” Chen, Y.; Li, P.; Modica, J. A.; Drout, R. J.; Farha, O. K.;  Am. Chem. Soc.; 2018, 140, pp. 5678-5681.

          Actinide-based MOFs

           The subject of actinide-based functional materials is substantially underexplored but is highly intriguing given the unique electronic structure of these elements, which includes 5f electrons. Controlling the bond formation of actinides could lead to materials with unconventional chemical, electronic, and magnetic properties. For example,  uranyl compounds exhibit ligand to metal charge transfer (LMCT) in the visible region and are luminescent. By capitalizing on and tailoring these properties, uranium compounds could be utilized  for catalytic degradation of water, photodegradation of organic dyes, oxidative combustion of volatile organic compounds, and activation of small molecules such as N2, CO, and CO2. Additionally, the uranium-based heavy fermion compounds exhibit a new type of superconductivity distinct from that of traditional superconductors. Trivalent and pentavalent uranium molecular compounds can display single-molecule magnet behavior with noticeably high relaxation barriers. The specific aims in Farha Group under this research topic include:

          1) Synthesize and characterize novel actinides-based materials.

          2) Understand the chemical bonding and processes that govern the formation of actinide-based materials.

          3) Customize and tailor functional actinides-based materials on demand.

          Selected Research Articles

          • “In Situ Formation of Unprecedented Neptunium-Oxide Wheel Clusters Stabilized in a Metal-Organic Framework.” Gilson, S.E.; Li, P.; Szymanowski, J.E.S.; White, J.; Ray, D.; Gagliardi, L.; Farha, O.K.; Burns, P.C.;  Am. Chem. Soc.; 2019141, pp. 11842-11846.
          • “Stabilization of an Unprecedented Hexanuclear Secondary Building Unit in a Thorium-Based Metal-Organic Framework.” Li, P.; Goswami, S.; Otake, K.; Wang, X.; Chen, Z.; Hanna, S.L.; Farha, O.K.;  Chem.; 201958, pp. 3586-3590.
          •  “Bottom-up construction of a superstructure in a porous uranium-organic crystal” Li, P.; Vermeulen, N. A.; Malliakas, C. D.; Gómez-Gualdrón, D. A.; Howarth, A. J.; Mehdi, B. L.; Dohnalkova, A.; Browning, N. D.; O’Keeffe, M.; Farha, O. K., Science 2017, 356, 624-627.
          • “Design and Synthesis of a Water-Stable Anionic Uranium-Based Metal–Organic Framework (MOF) with Ultra Large Pores” Li, P.; Vermeulen, N. A.; Gong, X.; Malliakas, C. D.; Stoddart, J. F.; Hupp, J. T.; Farha, O. K., Angew. Chem. 2016,128, 10514-10518.


            Heterogeneous Catalysis for Energy-Related Applications

            Catalysts composed of small metal/metal-oxide crystallites, well dispersed on porous solid materials, play essential roles in a variety of industrial gas-phase catalytic reactions including steam reforming, Fischer–Tropsch, and Haber–Bosch processes. As compared to conventional supports, the structures of MOFs, a class of porous materials comprised of organic linkers and inorganic nodes, are more readily tuned by rational ligand design. Furthermore, using crystalline MOFs as supports provides opportunities for atomically precise structural characterization of both active sites and supports, thereby facilitating detailed mechanistic studies of reactions.

            In the Farha group, two deposition techniques are used to anchor catalytically active metal ions to MOFs:

            1) solvothermal deposition in a MOF (SIM) and

            2) atomic layer deposition in a MOF (AIM).

            New MOF designs with other functionalities and enhanced stabilities are also being pursued.

            The targeted catalysis is mainly gas-phase transformations, including alkene hydrogenation and oligomerization, alkane oxidative dehydrogenation, and selective oxidation of alkanes to alcohols. Collaborating with beamline scientists at Argonne National Lab and theorists, we correlate the catalytic activity/product distribution with active-site structures to lay out the design rules for the discovery of improved catalysts.

            Selected Reviews

            • “Metal-Organic Frameworks: A Tunable Platform to Access Single-Site Heterogeneous Catalysts.” Wasson, M.C.; Buru, C.T.; Chen, Z.; Islamoglu, T.; Farha, O.K.; Applied Catalysis A, General2019, 586, pp. 117214.
            • “Postsynthetic Tuning of Metal–Organic Frameworks for Targeted Applications” Islamoglu, T.; Goswami, S.; Li, Z.; Howarth, A. J.; Farha, O. K.; Hupp, J. T.; Acc. Chem. Res.; 2017, 50, pp. 805-813
            • “NanoMOFs: little crystallites for substantial applications” Majewski, M. B.; Noh, H.; Islamoglu, T.; Farha, O. K.; Mat. Chem. A; 2018, 6, pp. 7338-7350

            Selected Research Articles

            • “Vanadium Catalyst on Isostructural Transition Metal, Lanthanide, and Actinide Based Metal-Organic Frameworks for Alcohol Oxidation” Wang, X.; Zhang, X.; Li, P.; Otake, K.I.; Cui, Y.; Lyu, J.; Krzyaniak, M.D.; Zhang, Y.; Li, Z.; Liu, J.; Buru, C.T.; Islamoglu, T.; Wasielewski, M.R.; Li, Z.; Farha, O.K.; Am. Chem. Soc.; 2019, 141, pp. 8306-8314
            • “Catalytic Chemoselective Functionalization of Methane in a Metal-Organic Framework” Zhang, X.; Huang, Z.; Ferrandon, M.; Yang, D.; Robison, L.; Li, P.; C Wang, T. C.; Delferro, M.; Farha, O. K.; Nature Catalysis; 2018, 1, pp. 356-362 org/10.1038/s41929-018-0069-6
            • “Single-Atom-Based Vanadium Oxide Catalysts Supported on Metal-Organic Frameworks: Selective Alcohol Oxidation and Structure Activity Relationship” Otake, K.; Cui, Y.; Buru, C. T.; Li, Z.; Hupp, J. T.; Farha, O. K.; Am. Chem. Soc.; 2018, 140, pp. 8652-8656
            • “Pushing the Limits on Metal-Organic Frameworks as a Catalyst Support: NU-1000 Supported Tungsten Catalysts for o-Xylene Isomerization and Disproportionation.” Ahn, S.; Nauert, S. L.; Buru, C. T.; Rimoldi, M.; Choi, H.; Schweitzer, N. M.;  Hupp, J. T.; Farha, O. K.; Notestein, J. M.;  Am. Chem. Soc.;2018, 140, pp. 8535-8543.


              Water Purification

              Clean water is becoming increasingly scarce and it is imperative we develop cost-efficient technologies capable of remediating large bodies of contaminated water. Rapid industrialization and agricultural growth in nations with minimal environmental regulations have caused extensive pollution. The presence of heavy metals such as lead and arsenic in what supplies is unacceptably common. And after several decades, the global environment is still recovering from the development, testing, and use of nuclear weapons during World War II and the Cold War.

              In the Farha group, we are combating water contamination using metal-organic frameworks (MOFs) by capitalizing on unique functionality at 1) the metal node and 2) the organic linker. We also use MOFs as scaffolds to probe individual characteristics that contribute to selective contaminant capture. The permanent crystallinity of MOFs and the ability to grow high-quality crystals allows for the characterization of binding motifs and mechanisms by crystallographic techniques. We will continue to develop new materials with specific applications in water purification.

              Selected Reviews

              • “Zirconium Metal-Organic Frameworks for Organic Pollutant Adsorption.” Drout, R.J.; Robison, L.; Chen, Z.; Islamoglu, T.;  Farha, O.K.; Trends in Chemistry 20193, pp. 304-317.

              Selected Research Articles

              • “Efficient Capture of Perrhenate and Pertechnetate by a Mesoporous Zr Metal–Organic Framework and Examination of Anion Binding Motifs” Drout, R. J.; Otake, K.; Howarth, A. J.; Islamoglu, T.; Zhu, L.; Xiao, C.; Wang, S.; Farha, O. K.; Mater.; 2018. 30, pp. 1277–1284
              • “Exploiting π-π Interactions to Design an Efficient Sorbent for Atrazine Removal from Water.” Akpinar, I.; Drout, R.J.; Islamoglu, T.; Kato, S.; Lyu, J.; Farha, O.K.; ACS Appl. Mater. Interfaces; 201911, pp. 6097-6103.
              • “Efficient extraction of inorganic selenium from water by a Zr metal-organic framework: investigation of volumetric uptake capacity and binding motifs.” Drout, R.J.; Howarth, A.J.; Otake, K.; Islamoglu, T.; Farha, O.K.; CrystEngComm.; 201820, pp. 6140-6145.
              • “99-TcO (4-) remediation by a cationic polymeric network.” Li, J.; Dai, X.; Zhu, L.; Xu, C.; Zhang, D.; Silver, M. A.; Li, P.; Chen, L.; Li, Y.; Zuo, D.; Zhang, H.; Xiao, C.; Chen, J.; Diwu, J.; Farha, O. K.; Albrecht-Schmitt, T. E.; Chai, Z.; Wang, S.; Nature Communications; 2018, 9, 3007.


                Gas Storage/Separation

                Metal–organic frameworks (MOFs) are an intriguing class of hybrid materials that are built by assembling metal centers with organic linkers. Through judicious choice of components, materials with permanent nanoscale porosity can be prepared. Some of the most notable examples have large internal surface areas and ultralow densities, with uniform cavities and voids with pre-designed molecular dimensions. These intriguing properties make them excellent candidates for small molecule storage and separation applications. The precise knowledge about the molecular structure of MOFs makes it possible to use highly accurate computational modeling of the static and dynamic interactions of guest molecules in the MOF pores to calculate adsorption isotherms, binding energies, and transport behavior, in both predictive and explanative modes. In Farha group, we design and synthesize MOFs with desired properties to store gases such as methane, hydrogen, oxygen or carbon dioxide, or separate industrially relevant gases.


                Selected Reviews/Highlights

                • “New directions in gas sorption and separation with MOFs: general discussion.” Addicoat, M.; Bennett, T.; Chapman, K.; Denysenko, D.; Dinca, M.; Doan, H.; Easun, T.; Eddaoudi, M.; Farha, O.; Gagliardi, L.; Haase, F.; Hajiahmadi Farmahini, A.; Hendon, C.; Jorge, M.; Kitagawa, S.; Lamberti, C.; Lee, J.-S. M.; Leus, K.; Li, J.; Lin, W.; Liu, X.; Lloyd, G.; Lu, C.; Ma, S.; Perez, J. P. H.; Ranocchiari, M.; Rosi, N.; Stassen, I.; Ting, V.; van der Veen, M.; Van Der Voort, P.; Vande Velde, C. M. L.; Volkmer, D.; Vornholt, S.; Walsh, A.; Yaghi, O. M.; Faraday Discuss.; 2017, 201, pp. 175-194

                Selected Publications

                • “Zirconium-Based Metal–Organic Framework with 9-Connected Nodes for Ammonia Capture.” Chen, Y.; Zhang, X.; Ma, K.; Chen, Z.; Wang, X.; Knapp, J.; Alayoglu, S.; Wang, F.; Xia, Q.; Li, Z.; Islamoglu, T.; Farha, O.K.; ACS Appl. Nano Mater.20192, pp. 6098-6102.
                • “Modular Synthesis of Highly Porous Zr-MOFs Assembled from Simple Building Blocks for Oxygen Storage.” Lyu, J.; Zhang, X.; Chen, Z.; Anderson, R.; Wang, X.; Wasson, M.C.; Bai, P.; Guo, X.; Islamoglu, T.; Gómez-Gualdrón, D.A.; Farha, O.K.; ACS Appl. Mater. Interfaces; Just Accepted Article; 2019.
                • “Ammonia Capture within Isoreticular Metal-Organic Frameworks with Rod Secondary Building Units.” Moribe, S.; Chen, Z.; Alayoglu, S.; Syed, Z.H.; Islamoglu, T.; Farha, O.K.; ACS Materials Lett.; 20191, pp. 476-480.
                • “Benchmark Study of Hydrogen Storage in Metal–Organic Frameworks under Temperature and Pressure Swing Conditions” García-Holley, P.; Schweitzer, B.; Islamoglu, T.; Liu, Y.; Lin, L.; Rodriguez, S.; Weston, M. H.; Hupp, J. T.; Gómez-Gualdrón, D. A.; Yildirim, T.; Farha, O. K.; ACS Energy Letters; 2018, 3, pp. 748-754
                • “Energy-based descriptors to rapidly predict hydrogen storage in metal-organic frameworks.” Bucior, B.J.; Bobbitt, N.S.; Islamoglu, T.; Goswami, S.; Gopalan, A.; Yildrim, T.; Farha, O.K.; Bagheri, N.; Snurr, R.Q.;  Syst. Des. Eng.; 2019, 4, pp. 162-174.
                • “Computer-aided discovery of a metal–organic framework with superior oxygen uptake.” Moghadam, P. Z.; Islamoglu, T.; Goswami, S.; Exley, J.; Fantham, M.; Kaminski, C. F.; Snurr, R. Q.; Farha, O. K.; Fairen-Jimenez, D.; Nature Communications; 2018, 9, 1378.

                  Chemical Separation

                  Chemical separations typically leverage the different physical and chemical properties of the species in the mixture to isolate one compound. Some properties, like boiling point, have been used for centuries to purify compounds, but distillation is an energy-intensive and expensive technique on an industrial scale. MOFs have been shown to serve as capable agents for separation technology, often relying on changes in pore size or Lewis basic sites to isolate the desired molecules. We are interested in leveraging the tunability of MOFs to study how the three-dimensional structure of these materials impacts their performance in challenging, shape-selective separations. In addition, we are investigating “reactive-separations” that utilize MOF-based catalysts to simplify a ternary mixture to a binary mixture that can be separated based on traditional absorbance-based techniques.


                  Selected Publications

                  • “Zirconium-Based Metal-Organic Frameworks for the Removal of Protein-Bound Uremic Toxin from Human Serum Albumin.” Kato, S.; Otake, K.; Chen, H.; Akpinar, I.; Buru, C.T.; Islamoglu, T.; Snurr, R.Q.; Farha, O.K.;   Am. Chem. Soc.;2019141, pp. 2568-2576.
                  • “Highly Selective Acetylene Semihydrogenation Catalyzed by Cu Nanoparticles Supported in a Metal-Organic Framework” Redfern, L. R.; Li, Z.; Zhang, X.; Farha, O. K.; ACS Appl. Nano Mater.; 2018, 1, pp. 4413-4417 org/10.1021/acsanm.8b01397
                  • “Effect of ionic liquid on sugar-aromatic separation selectivity by metal-organic framework NU-1000 in aqueous solution.” Yabushita, M.; Papa, G.; Li, P.; Fukuoka, A.; Farha, O.K.; Simmons, B.A.; Katz, A.; Fuel Process. Technol.; Just Accepted Article, 2019. org/10.1016/j.fuproc.2019.106189
                  • “Tuning ethylene gas adsorption via metal node modulation: Cu-MOF-74 for a high ethylene deliverable capacity” Liao, Y.; Zhang, L.; Weston, M. H.; Morris, W.; Hupp, J. T.; Farha, O. K.; Chem. Commun.; 2017, 53, pp. 9376-9379 org/10.1039/C7CC04160H

                    Physical and Chemical Stability of MOFs

                    Despite the extensive pursuit of design rules that describe MOF structural and chemical stability, the physical stability of MOFs under high pressure (i.e. compression) and low pressure (i.e. vacuum) remains largely underexplored. Understanding how the multi-dimensional structure of these porous frameworks dictates their behavior under extreme pressures is both fundamentally important and practically relevant for applications requiring pellet formation. Recent efforts in the Farha lab set out to understand the role of the organic linker in the compression of MOFs at high pressures.  We investigated the pressure-response of MOFs using a diamond anvil cell and in-situ PXRD at the Advanced Photon Source at Argonne National Lab. As we continue to explore the pressure-response of MOFs, we will continue to develop structure-property relationships centered around various MOF components. Understanding the impact of topology on structure stability will allow us to design better materials for a variety of applications, including CWA degradation.


                    Selected Reviews

                    “Mechanical properties of metal-organic frameworks” Redfern, L.R.; Farha, O.K.; Chemical Science; 2019, 10, 10666.

                    “Chemical, thermal and mechanical stabilities of metal–organic frameworks” Howarth, A. J.; Liu, Y.; Li, P.; Li, Z.; Wang, T. C.; Hupp, J. T.; Farha, O. K.; Nature Reviews Materials; 2016, 1, pp. 15018

                    Selected Research Articles

                    • “Porosity Dependence of Compression and Lattice Rigidity in Metal-Organic Framework Series” Redfern, L.R.; Robison, L.; Wasson, M.C.; Goswami, S.; Lyu, J.; Islamoglu, T.; Chapman, K.W.; Farha, O.K. Am. Chem. Soc.; 2019, 141, pp. 4365-4371
                    • “Torsion Angle Effect on the Activation of UiO Metal-Organic Frameworks” Ayoub, G.; Islamoglu, T.; Goswami, S.; Friščić, T.; Farha, O.K.; ACS Appl. Mater. Interfaces; 2019, 11, pp. 15788-15794 org/10.1021/acsami.9b02764

                    “Water stabilization of Zr6-based metal-organic frameworks via solvent-assisted ligand incorporation.” Deria, P.; Chung, Y. G.; Snurr, R. Q.; Hupp, J. T.; Farha, O. K., Chemical Science 2015, 6, 5172-5176.

                    Characterization Tools for MOFs

                    In the Farha group, we are interested in establishing reliable and transferrable methods that allow us and the scientific community to advance our understanding of MOF formation process as well as interactions of the substrates with MOFs. Therefore, we have begun using isothermal titration calorimetry (ITC) to quantify the strength and type of interactions (e.g. coordination, H-bonding, hydrophobic effect) between analytes and sorbents. We utilized potentiometric titration on Zr-MOFs which allowed us to determine the proton topology, therefore, the defects present in these kinds of MOFs. In situ powder X-ray diffraction powder X-ray diffraction (PXRD) measurements accompanied by high resolution transmission electron microscopy (HR-TEM), we characterize not only the thermodynamic MOF products, but also the kinetic products formed during the synthesis.



                    Selected Publications

                    • “Interrogating Kinetic versus Thermodynamic Topologies of Metal-Organic Frameworks via Combined Transmission Electron Microscopy and X-ray Diffraction Analysis” Gong, X.; Noh, H.; Gianneschi, N.C.; Farha, O.K.; Am. Chem. Soc.; 2019, 141, pp. 6146-615.
                    • “Evaluation of Bronsted acidity and proton topology in Zr- and Hf-based metal-organic frameworks using potentiometric acid-base titration” Klet, R. C.; Liu, Y.; Wang, T. C.; Hupp, J. T.; Farha, O. K.; Mat. Chem. A 2016, 4, pp. 1479-1485
                    • ….more coming soon.

                    Porous Organic Polymers

                    In the Farha group, by means of new materials chemistry capabilities developed by our group, we design, engineer, and construct porous polymers for capturing toxic gases such as ammonia and sulfur dioxide as well as for water purification. Furthermore, we also design and synthesize highly reactive porous and processable polymers that can react with organo-phosphate/phosphonate nerve agents, sulfur mustard blistering agents, and their simulants for potential use in protective gear.