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Liu J, Redfern LR, Liao Y, Islamoglu T, Atilgan A, Farha OK, Hupp JT. Metal-Organic-Framework-Supported and -Isolated Ceria Clusters with Mixed Oxidation States. ACS APPLIED MATERIALS & INTERFACES 2019; 11:47822-47829. [PMID: 31790199 DOI: 10.1021/acsami.9b12261] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The formation of oxygen vacancies via reversible transitions between Ce(IV) and Ce(III) plays a crucial role in the propensity of cerium oxide to act as a supporting promoter in oxidative heterogeneous catalysis. An open challenge is, however, preparation of high-porosity, supported arrays of isolated ceria(IV, III) clusters with high porosity. Herein, we report two examples of oxy-Ce(IV, III) clusters supported and spatially isolated on an oxy-zirconium MOF, NU-1000. The clusters are introduced using either of two Ce complexes (precursors): CeIV(tmhd)4 (tmhd = 2,2,6,6-tetramethyl-3,5-heptanedionate) or CeIII(iPrCp)3 (iPrCp = tris(isopropyl-cyclopenta-dienyl), via SIM (solvothermal installation in MOFs). The prepared materials are named Ce-l-SIM-NU-1000 and Ce-n-SIM-NU-1000, respectively. X-ray photoelectron spectroscopy characterization shows that the ratio of Ce(III) to Ce(IV) oxidation states can be modulated. Difference envelope density analyses of X-ray scattering show that CexOyHz clusters in Ce-n-SIM-NU-1000 are located between pairs of Zr6 nodes, whereas in Ce-l-SIM-NU-1000, they are sited on MOF linkers throughout the micropores of NU-1000. Cluster size differences were further evaluated by pair function distribution (PDF) analyses of total X-ray scattering reveal that the node sited clusters contain of only a few cerium ions, whereas the linker-sited clusters each contain ∼90 cerium ions. The observed size appears to be defined by the size of NU-1000s triangular pores, that is, cluster formation appears to be pore templated. The Ce-SIM functionalized materials are catalytically active for hydrolysis of DMNP (dimethyl 4-nitrophenyl phosphate), a nerve-agent simulant. Conversion of a small fraction of the Ce(IV) ions in which the presence of small fractions of the cerium(IV) ions in Ce-l-SIM-NU-1000 to cerium(III) significantly enhances catalytic activity-perhaps by labilizing aqua ligands and facilitating simulant binding to the clusters Lewis-basic metal ions. While not explored here, the larger clusters, when partially reduced, are, we believe, candidate catalysts for O2 activation and subsequent selective oxidation of organic substrates.
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Goswami S, Hod I, Duan JD, Kung CW, Rimoldi M, Malliakas CD, Palmer RH, Farha OK, Hupp JT. Anisotropic Redox Conductivity within a Metal-Organic Framework Material. J Am Chem Soc 2019; 141:17696-17702. [PMID: 31608628 DOI: 10.1021/jacs.9b07658] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Engendering electrical conductivity in otherwise insulating metal-organic framework (MOF) materials is key to rendering these materials fully functional for a range of potential applications, including electrochemical and photo-electrochemical catalysis. Here we report that the platform MOF, NU-1000, can be made electrically conductive via reversible electrochemical oxidation of a fraction of the framework's tetraphenylpyrene linkers, where the basis for conduction is redox hopping. At a microscopic level, redox hopping is akin to electron self-exchange and is describable by Marcus' well-known theory of electron transfer. At a macroscopic level, the hopping behavior leads to diffusive charge transport and is quantifiable as an apparent diffusion coefficient, Dhopping. Theory suggests that the csq topology of NU-1000, together with its characteristic one-dimensional mesopores, will result in direction-dependent, that is, anisotropic, electrical conductivity. Detailed computations suggest that the governing factor is the strength of electronic coupling between pairs of linkers sited in the a,b plane of the MOF versus the mesopore-aligned c axis of the crystal. The notion has been put to the test experimentally by configuring the MOF as an array of selectively oriented, electrode-supported crystallites, where the rodlike crystallites are either oriented largely normal to the electrode (requiring redox hopping along the c direction) or mainly parallel (requiring redox hopping mainly through the a,b plane). The orientations are preselected by preparing MOF films either via interfacial solvothermal synthesis or via electrophoretic deposition. In semiquantitative accord with computational predictions, Dhopping is up to ∼3500 times larger in the c direction than through the a,b plane. In addition to their fundamental significance, the findings have clear implications for the design and optimization of MOFs for electrocatalysis and for other applications that rely upon electrical conductivity.
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Zheng J, Ye J, Ortuño MA, Fulton JL, Gutiérrez OY, Camaioni DM, Motkuri RK, Li Z, Webber TE, Mehdi BL, Browning ND, Penn RL, Farha OK, Hupp JT, Truhlar DG, Cramer CJ, Lercher JA. Selective Methane Oxidation to Methanol on Cu-Oxo Dimers Stabilized by Zirconia Nodes of an NU-1000 Metal-Organic Framework. J Am Chem Soc 2019; 141:9292-9304. [PMID: 31117650 DOI: 10.1021/jacs.9b02902] [Citation(s) in RCA: 86] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mononuclear and dinuclear copper species were synthesized at the nodes of an NU-1000 metal-organic framework (MOF) via cation exchange and subsequent oxidation at 200 °C in oxygen. Copper-exchanged MOFs are active for selectively converting methane to methanol at 150-200 °C. At 150 °C and 1 bar methane, approximately a third of the copper centers are involved in converting methane to methanol. Methanol productivity increased by 3-4-fold and selectivity increased from 70% to 90% by increasing the methane pressure from 1 to 40 bar. Density functional theory showed that reaction pathways on various copper sites are able to convert methane to methanol, the copper oxyl sites with much lower free energies of activation. Combining studies of the stoichiometric activity with characterization by in situ X-ray absorption spectroscopy and density functional theory, we conclude that dehydrated dinuclear copper oxyl sites formed after activation at 200 °C are responsible for the activity.
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Otake KI, Ye J, Mandal M, Islamoglu T, Buru CT, Hupp JT, Delferro M, Truhlar DG, Cramer CJ, Farha OK. Enhanced Activity of Heterogeneous Pd(II) Catalysts on Acid-Functionalized Metal–Organic Frameworks. ACS Catal 2019. [DOI: 10.1021/acscatal.9b01043] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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55
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Liu J, Li Z, Zhang X, Otake KI, Zhang L, Peters AW, Young MJ, Bedford NM, Letourneau SP, Mandia DJ, Elam JW, Farha OK, Hupp JT. Introducing Nonstructural Ligands to Zirconia-like Metal–Organic Framework Nodes To Tune the Activity of Node-Supported Nickel Catalysts for Ethylene Hydrogenation. ACS Catal 2019. [DOI: 10.1021/acscatal.8b04828] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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56
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Berijani K, Morsali A, Hupp JT. An effective strategy for creating asymmetric MOFs for chirality induction: a chiral Zr-based MOF for enantioselective epoxidation. Catal Sci Technol 2019. [DOI: 10.1039/c9cy00565j] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
A simple and rapid procedure was used to prepare chiral NU-1000 as a robust Zr-based MOF without complexity. The functionalization of NU-1000 was performed by utilizing chirall-(+)-tartaric acidviasolvent-assisted linker incorporation, resulting in [C-NU-1000]. A Mo-complex was immobilized onto chiral NU-1000 for enantioselective epoxidation.
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Palmer RH, Kung CW, Liu J, Farha OK, Hupp JT. Nickel-Carbon-Zirconium Material Derived from Nickel-Oxide Clusters Installed in a Metal-Organic Framework Scaffold by Atomic Layer Deposition. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:14143-14150. [PMID: 30380883 DOI: 10.1021/acs.langmuir.8b02166] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Atomic layer deposition is employed to install nickel oxide into NU-1000. Upon heating to 900 °C under nitrogen, a carbon material containing ZrO2 and Ni is formed. In notable contrast to the parent metal-organic framework, the pyrolyzed material is: (a) stable in highly alkaline solutions (typical conditions for water electro-oxidation) and (b) electrically conductive and thus able to deliver oxidizing equivalents (holes) to catalytic sites located far from the underlying conductive-glass electrode. The pyrolysis-derived material was characterized and its electrocatalytic activity for oxygen evolution was investigated.
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da Silva CTP, Howarth AJ, Rimoldi M, Islamoglu T, Rinaldi AW, Hupp JT. Phosphonates Meet Metal−Organic Frameworks: Towards CO
2
Adsorption. Isr J Chem 2018. [DOI: 10.1002/ijch.201800129] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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59
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Goswami S, Chen M, Wasielewski MR, Farha OK, Hupp JT. Boosting Transport Distances for Molecular Excitons within Photoexcited Metal-Organic Framework Films. ACS APPLIED MATERIALS & INTERFACES 2018; 10:34409-34417. [PMID: 30207679 DOI: 10.1021/acsami.8b14977] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Herein, we describe the fabrication of porphyrin-containing metal-organic framework thin films with 1,4-diazabicyclo[2.2.2]octane (DABCO) pillaring linkers and investigate exciton transport within the films. Steady-state emission spectroscopy indicates that the exciton can traverse up to 26 porphyrin layers when DABCO is used as a pillaring linker, whereas on average only 9-11 layers can be traversed when either 4,4'-bipyridine (a pillaring linker) or pyridine (a nonpillaring, layer-interdigitating ligand) is used. These results can be understood by taking into account the decreased separation distances between transition dipoles associated with chromophores (porphyrins) sited in adjacent layers. Shorter distances translate into faster Förster-type exciton hopping and, therefore, more hops within the few nanosecond lifetime of the porphyrin's singlet excited-state. The findings have favorable implications for the development of MOF-based photoelectrodes and photoelectrochemical energy-conversion devices.
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Kung CW, Platero-Prats AE, Drout RJ, Kang J, Wang TC, Audu CO, Hersam MC, Chapman KW, Farha OK, Hupp JT. Inorganic "Conductive Glass" Approach to Rendering Mesoporous Metal-Organic Frameworks Electronically Conductive and Chemically Responsive. ACS APPLIED MATERIALS & INTERFACES 2018; 10:30532-30540. [PMID: 30113802 DOI: 10.1021/acsami.8b08270] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
A representative mesoporous metal-organic-framework (MOF) material, NU-1000, has been rendered electronically conductive via a robust inorganic approach that permits retention of MOF crystallinity and porosity. The approach is based on condensed-phase grafting of molecular tin species onto the MOF nodes via irreversible reaction with hydroxyl and aqua ligands presented at the node surface, a self-limiting process termed solvothermal installation (of metal ions) in MOFs (SIM, a solution-phase analog of atomic layer deposition in MOFs). Treatment of the modified MOF with aerated steam at 120 °C converts the grafted tin molecules to tetratin(IV)oxy clusters, with the clusters being sited between insulating pairs of zirconia-like nodes (the zirconium component being key to endowing the parent material with requisite chemical and thermal stability). By introducing new O-H presenting ligands on the modified-MOF node, the high-temperature steam step additionally serves to reset the material to reactive form, thus enabling a second self-limiting tin-grafting step to be run (and after further steam treatment, enabling a third). Difference-envelop-density (DED) analyses of synchrotron-derived X-ray scattering data, with and without installed tin species, show that the clusters formed after one cycle are spatially isolated, but that repetitive SIM cycling adds metal and oxygen ions in a way that enshrouds nodes, links clusters, and yields continuous one-dimensional strands of oxy-tin(IV), oriented exclusively along the c axis of the MOF. Two-probe conductivity measurements show that the parent MOF and the version containing isolated oxy-tin(IV) clusters are electrically insulating, but that the versions featuring continuous strands show an electrical conductivity of 1.8 × 10-7 S/cm after three Sn-SIM cycles. When combined with interdigitated microelectrodes, the solvent-free and conductive-glass-modified material (three Sn-SIM cycles) displays a substantial and persistent increase in electrical conductivity during exposure to 5% H2, indicating a role for dissociated H2 as an electronic dopant. The increase can be repetitively reversed by alternating H2 with air, illustrating the ability of the conductive MOF to function as a resistive sensor for H2 and suggesting further potential applications that may capitalize on the combination of high volumetric surface area, high mesoporosity, high chemical and thermal stability, and significant electrical conductivity.
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61
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Noh H, Kung CW, Otake KI, Peters AW, Li Z, Liao Y, Gong X, Farha OK, Hupp JT. Redox-Mediator-Assisted Electrocatalytic Hydrogen Evolution from Water by a Molybdenum Sulfide-Functionalized Metal–Organic Framework. ACS Catal 2018. [DOI: 10.1021/acscatal.8b02921] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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62
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Liu J, Ye J, Li Z, Otake KI, Liao Y, Peters AW, Noh H, Truhlar DG, Gagliardi L, Cramer CJ, Farha OK, Hupp JT. Beyond the Active Site: Tuning the Activity and Selectivity of a Metal-Organic Framework-Supported Ni Catalyst for Ethylene Dimerization. J Am Chem Soc 2018; 140:11174-11178. [PMID: 30141922 DOI: 10.1021/jacs.8b06006] [Citation(s) in RCA: 74] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
To modify its steric and electronic properties as a support for heterogeneous catalysts, electron-withdrawing and electron-donating ligands, hexafluoroacetylacetonate (Facac-) and acetylacetonate (Acac-), were introduced to the metal-organic framework (MOF), NU-1000, via a process akin to atomic layer deposition (ALD). In the absence of Facac- or Acac-, NU-1000-supported, AIM-installed Ni(II) sites yield a mixture of C4, C6, C8, and polymeric products in ethylene oligomerization. (AIM = ALD-like deposition in MOFs). In contrast, both Ni-Facac-AIM-NU-1000 and Ni-Acac-AIM-NU-1000 exhibit quantitative catalytic selectivity for C4 species. Experimental findings are supported by density functional theory calculations, which show increases in the activation barrier for the C-C coupling step, due mainly to rearrangement of the siting of Facac- or Acac- to partially ligate added nickel. The results illustrate the important role of structure-tuning support modifiers in controlling the activity of MOF-sited heterogeneous catalysts and in engendering catalytic selectivity. The results also illustrate the ease with which crystallographically well-defined modifications of the catalyst support can be introduced when the node-coordinating molecular modifier is delivered via the vapor phase.
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63
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Doan HA, Li Z, Farha OK, Hupp JT, Snurr RQ. Theoretical insights into direct methane to methanol conversion over supported dicopper oxo nanoclusters. Catal Today 2018. [DOI: 10.1016/j.cattod.2018.03.063] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
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64
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Otake KI, Cui Y, Buru CT, Li Z, Hupp JT, Farha OK. Single-Atom-Based Vanadium Oxide Catalysts Supported on Metal-Organic Frameworks: Selective Alcohol Oxidation and Structure-Activity Relationship. J Am Chem Soc 2018; 140:8652-8656. [PMID: 29950097 DOI: 10.1021/jacs.8b05107] [Citation(s) in RCA: 137] [Impact Index Per Article: 22.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
We report the syntheses, structures, and oxidation catalytic activities of a single-atom-based vanadium oxide incorporated in two highly crystalline MOFs, Hf-MOF-808 and Zr-NU-1000. These vanadium catalysts were introduced by a postsynthetic metalation, and the resulting materials (Hf-MOF-808-V and Zr-NU-1000-V) were thoroughly characterized through a combination of analytic and spectroscopic techniques including single-crystal X-ray crystallography. Their catalytic properties were investigated using the oxidation of 4-methoxybenzyl alcohol under an oxygen atmosphere as a model reaction. Crystallographic and variable-temperature spectroscopic studies revealed that the incorporated vanadium in Hf-MOF-808-V changes position with heat, which led to improved catalytic activity.
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Ahn S, Nauert SL, Buru CT, Rimoldi M, Choi H, Schweitzer NM, Hupp JT, Farha OK, Notestein JM. Pushing the Limits on Metal–Organic Frameworks as a Catalyst Support: NU-1000 Supported Tungsten Catalysts for o-Xylene Isomerization and Disproportionation. J Am Chem Soc 2018; 140:8535-8543. [DOI: 10.1021/jacs.8b04059] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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66
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Goswami S, Ray D, Otake KI, Kung CW, Garibay SJ, Islamoglu T, Atilgan A, Cui Y, Cramer CJ, Farha OK, Hupp JT. A porous, electrically conductive hexa-zirconium(iv) metal-organic framework. Chem Sci 2018; 9:4477-4482. [PMID: 29896389 PMCID: PMC5956983 DOI: 10.1039/c8sc00961a] [Citation(s) in RCA: 99] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 04/11/2018] [Indexed: 12/23/2022] Open
Abstract
Engendering electrical conductivity in high-porosity metal-organic frameworks (MOFs) promises to unlock the full potential of MOFs for electrical energy storage, electrocatalysis, or integration of MOFs with conventional electronic materials. Here we report that a porous zirconium-node-containing MOF, NU-901, can be rendered electronically conductive by physically encapsulating C60, an excellent electron acceptor, within a fraction (ca. 60%) of the diamond-shaped cavities of the MOF. The cavities are defined by node-connected tetra-phenyl-carboxylated pyrene linkers, i.e. species that are excellent electron donors. The bulk electrical conductivity of the MOF is shown to increase from immeasurably low to 10-3 S cm-1, following fullerene incorporation. The observed conductivity originates from electron donor-acceptor interactions, i.e. charge-transfer interactions - a conclusion that is supported by density functional theory calculations and by the observation of a charge-transfer-derived band in the electronic absorption spectrum of the hybrid material. Notably, the conductive version of the MOF retains substantial nanoscale porosity and continues to display a sizable internal surface area, suggesting potential future applications that capitalize on the ability of the material to sorb molecular species.
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67
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Gong X, Zhou J, Hartlieb KJ, Miller C, Li P, Farha OK, Hupp JT, Young RM, Wasielewski MR, Stoddart JF. Toward a Charged Homo[2]catenane Employing Diazaperopyrenium Homophilic Recognition. J Am Chem Soc 2018; 140:6540-6544. [DOI: 10.1021/jacs.8b03407] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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68
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Peters AW, Otake K, Platero-Prats AE, Li Z, DeStefano MR, Chapman KW, Farha OK, Hupp JT. Site-Directed Synthesis of Cobalt Oxide Clusters in a Metal-Organic Framework. ACS APPLIED MATERIALS & INTERFACES 2018; 10:15073-15078. [PMID: 29671320 DOI: 10.1021/acsami.8b02825] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Direct control over structure and location of catalytic species deposited on amorphous supports represents a formidable challenge in heterogeneous catalysis. In contrast, a structurally well-defined, crystalline metal-organic framework (MOF) can be rationally designed using postsynthetic techniques to allow for desired structural or locational changes of deposited metal ions. Herein, naphthalene dicarboxylate linkers are incorporated in the MOF, NU-1000, to block the small cavities where few-atom clusters of cobalt oxide preferentially grow, inducing catalyst deposition toward hitherto ill-favored grafting sites orientated toward NU-1000s mesoporous channels. Despite the different cobalt oxide location, the resulting material is still an active propane oxidative dehydrogenation catalyst at low temperature, reaching a turnover frequency of 0.68 ± 0.05 h-1 at 230 °C and confirming the utility of MOFs as crystalline supports to guide rational design of catalysts.
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Palmer RH, Liu J, Kung CW, Hod I, Farha OK, Hupp JT. Electroactive Ferrocene at or near the Surface of Metal-Organic Framework UiO-66. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:4707-4714. [PMID: 29652507 DOI: 10.1021/acs.langmuir.7b03846] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Here, we describe the installation of a ferrocene derivative on and within the archetypal metal-organic framework (MOF), UiO-66, by solvent-assisted ligand incorporation. Thin films of the resulting material show a redox peak characteristic of the Fc/Fc+ couple, as measured by cyclic voltammetry. Consistent with restriction of redox reactivity solely to Fc molecules sited at or near the external surfaces of MOF crystallites, chronoamperometry measurements indicate that less than 20% of the installed Fc molecules are electrochemically active. Charge-transport diffusion coefficients, DCT, of 6.1 ± 0.8 × 10-11 and 2.6 ± 0.2 × 10-9 cm2/s were determined from potential step measurements, stepping oxidatively and reductively, respectively. The 40-fold difference in DCT values contrasts with the expectation, for simple systems, of identical values for oxidation-driven versus reduction-driven charge transport. The findings have implications for the design of MOFs suitable for delivery of redox equivalents to framework-immobilized electrocatalysts and/or delivery of charges from a chromophoric MOF film to an underlying electrode, processes that may be central to MOF-facilitated conversion of solar energy to chemical or electrical energy.
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70
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Pereira CF, Figueira F, Mendes RF, Rocha J, Hupp JT, Farha OK, Simões MMQ, Tomé JPC, Paz FAA. Bifunctional Porphyrin-Based Nano-Metal-Organic Frameworks: Catalytic and Chemosensing Studies. Inorg Chem 2018. [PMID: 29533608 DOI: 10.1021/acs.inorgchem.7b03214] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The use of 5,10,15,20-tetrakis( p-phenylphosphonic acid)porphyrin (H10TPPA) as a linker in the preparation of porphyrin-based metal-organic frameworks (Por-MOFs) through coordination to lanthanides cations is reported. The resulting unprecedented materials, formulated as [M(H9TPPA)(H2O) x]Cl2· yH2O [ x + y = 7; M3+ = La3+ (1), Yb3+ (2), and Y3+ (3)], prepared using hydrothermal synthesis, were extensively characterized in the solid-state, for both their structure and thermal robustness, using a myriad of solid-state advanced techniques. Materials were evaluated as heterogeneous catalysts in the oxidation of thioanisole by H2O2 and as chemosensors for detection of nitroaromatic compounds (NACs). Nano-Por-MOFs 1-3 proved to be effective as heterogeneous catalysts in the sulfoxidation of thioanisole, with Por-MOF 1 exhibiting the best catalytic performance with a conversion of thioanisole of 89% in the first cycle and with a high selectivity for the sulfoxide derivative (90%). The catalyst maintained its activity roughly constant in three consecutive runs. Por-MOFs 1-3 can be employed as chemosensors because of a measured fluorescence quenching up to 70% for nitrobenzene, 1,4-dinitrobenzene, 4-nitrophenol, and phenol, with 2,4,6-trinitrophenol exhibiting a peculiar fluorescence profile.
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Kung CW, Otake K, Buru CT, Goswami S, Cui Y, Hupp JT, Spokoyny AM, Farha OK. Increased Electrical Conductivity in a Mesoporous Metal-Organic Framework Featuring Metallacarboranes Guests. J Am Chem Soc 2018; 140:3871-3875. [PMID: 29502408 DOI: 10.1021/jacs.8b00605] [Citation(s) in RCA: 127] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Nickel(IV) bis(dicarbollide) is incorporated in a zirconium-based metal-organic framework (MOF), NU-1000, to create an electrically conductive MOF with mesoporosity. All the nickel bis(dicarbollide) units are located as guest molecules in the microporous channels of NU-1000, which permits the further incorporation of other active species in the remaining mesopores. For demonstration, manganese oxide is installed on the nodes of the electrically conductive MOF. The electrochemically addressable fraction and specific capacitance of the manganese oxide in the conductive framework are more than 10 times higher than those of the manganese oxide in the parent MOF.
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72
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Wu Y, Bobbitt NS, Logsdon JL, Powers‐Riggs NE, Nelson JN, Liu X, Wang TC, Snurr RQ, Hupp JT, Farha OK, Hersam MC, Wasielewski MR. Tunable Crystallinity and Charge Transfer in Two‐Dimensional G‐Quadruplex Organic Frameworks. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201800230] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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73
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Wu Y, Bobbitt NS, Logsdon JL, Powers‐Riggs NE, Nelson JN, Liu X, Wang TC, Snurr RQ, Hupp JT, Farha OK, Hersam MC, Wasielewski MR. Tunable Crystallinity and Charge Transfer in Two‐Dimensional G‐Quadruplex Organic Frameworks. Angew Chem Int Ed Engl 2018; 57:3985-3989. [DOI: 10.1002/anie.201800230] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Indexed: 11/10/2022]
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74
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Malonzo CD, Wang Z, Duan J, Zhao W, Webber TE, Li Z, Kim IS, Kumar A, Bhan A, Platero-Prats AE, Chapman KW, Farha OK, Hupp JT, Martinson ABF, Penn RL, Stein A. Application and Limitations of Nanocasting in Metal–Organic Frameworks. Inorg Chem 2018; 57:2782-2790. [DOI: 10.1021/acs.inorgchem.7b03181] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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75
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Avila JR, Peters AW, Li Z, Ortuño MA, Martinson ABF, Cramer CJ, Hupp JT, Farha OK. Atomic layer deposition of Cu(i) oxide films using Cu(ii) bis(dimethylamino-2-propoxide) and water. Dalton Trans 2018; 46:5790-5795. [PMID: 28406498 DOI: 10.1039/c6dt02572b] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
To grow films of Cu2O, bis-(dimethylamino-2-propoxide)Cu(ii), or Cu(dmap), is used as an atomic layer deposition precursor using only water vapor as a co-reactant. Between 110 and 175 °C, a growth rate of 0.12 ± 0.02 Å per cycle was measured using an in situ quartz crystal microbalance (QCM). X-ray photoelectron spectroscopy (XPS) confirms the growth of metal-oxide films featuring Cu(i).
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