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Linares-Moreau M, Brandner LA, Velásquez-Hernández MDJ, Fonseca J, Benseghir Y, Chin JM, Maspoch D, Doonan C, Falcaro P. Fabrication of Oriented Polycrystalline MOF Superstructures. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2309645. [PMID: 38018327 DOI: 10.1002/adma.202309645] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 10/19/2023] [Indexed: 11/30/2023]
Abstract
The field of metal-organic frameworks (MOFs) has progressed beyond the design and exploration of powdery and single-crystalline materials. A current challenge is the fabrication of organized superstructures that can harness the directional properties of the individual constituent MOF crystals. To date, the progress in the fabrication methods of polycrystalline MOF superstructures has led to close-packed structures with defined crystalline orientation. By controlling the crystalline orientation, the MOF pore channels of the constituent crystals can be aligned along specific directions: these systems possess anisotropic properties including enhanced diffusion along specific directions, preferential orientation of guest species, and protection of functional guests. In this perspective, we discuss the current status of MOF research in the fabrication of oriented polycrystalline superstructures focusing on the specific crystalline directions of orientation. Three methods are examined in detail: the assembly from colloidal MOF solutions, the use of external fields for the alignment of MOF particles, and the heteroepitaxial ceramic-to-MOF growth. This perspective aims at promoting the progress of this field of research and inspiring the development of new protocols for the preparation of MOF systems with oriented pore channels, to enable advanced MOF-based devices with anisotropic properties.
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Affiliation(s)
- Mercedes Linares-Moreau
- Institute of Physical and Theoretical Chemistry, Graz University of Technology, Graz, 8010, Austria
| | - Lea A Brandner
- Institute of Physical and Theoretical Chemistry, Graz University of Technology, Graz, 8010, Austria
| | | | - Javier Fonseca
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, Barcelona, 08193, Spain
| | - Youven Benseghir
- Faculty of Chemistry, Institute of Functional Materials and Catalysis, University of Vienna, Währingerstr. 42, Vienna, A-1090, Austria
| | - Jia Min Chin
- Faculty of Chemistry, Institute of Functional Materials and Catalysis, University of Vienna, Währingerstr. 42, Vienna, A-1090, Austria
| | - Daniel Maspoch
- Catalan Institute of Nanoscience and Nanotechnology (ICN2), CSIC and The Barcelona Institute of Science and Technology, Campus UAB, Bellaterra, Barcelona, 08193, Spain
- Departament de Química, Facultat de Ciències, Universitat Autònoma de Barcelona (UAB), Cerdanyola del Vallès, Barcelona, 08193, Spain
- ICREA, Pg. Lluís Companys 23, Barcelona, 08010, Spain
| | - Christian Doonan
- Department of Chemistry, The University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Paolo Falcaro
- Institute of Physical and Theoretical Chemistry, Graz University of Technology, Graz, 8010, Austria
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2
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Verma PK, Koellner CA, Hall H, Phister MR, Stone KH, Nichols AW, Dhakal A, Ashcraft E, Machan CW, Giri G. Solution Shearing of Zirconium (Zr)-Based Metal-Organic Frameworks NU-901 and MOF-525 Thin Films for Electrocatalytic Reduction Applications. ACS APPLIED MATERIALS & INTERFACES 2023; 15:53913-53923. [PMID: 37955400 DOI: 10.1021/acsami.3c12011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2023]
Abstract
Solution shearing, a meniscus-guided coating process, can create large-area metal-organic framework (MOF) thin films rapidly, which can lead to the formation of uniform membranes for separations or thin films for sensing and catalysis applications. Although previous work has shown that solution shearing can render MOF thin films, examples have been limited to a few prototypical systems, such as HKUST-1, Cu-HHTP, and UiO-66. Here, we expand on the applicability of solution shearing by making thin films of NU-901, a zirconium-based MOF. We study how the NU-901 thin film properties (i.e., crystallinity, surface coverage, and thickness) can be controlled as a function of substrate temperature and linker concentration. High fractional surface coverage of small-area (∼1 cm2) NU-901 thin films (0.88 ± 0.06) is achieved on a glass substrate for all conditions after one blade pass, while a low to moderate fractional surface coverage (0.73 ± 0.18) is obtained for large-area (∼5 cm2) NU-901 thin films. The crystallinity of NU-901 crystals increases with temperature and decreases with linker concentration. On the other hand, the adjusted thickness of NU-901 thin films increases with both increasing temperature and linker concentration. We also extend the solution shearing technique to synthesize MOF-525 thin films on a transparent conductive oxide that are useful for electrocatalysis. We show that Fe-metalated MOF-525 films can reduce CO2 to CO, which has implications for CO2 capture and utilization. The demonstration of thin film formation of NU-901 and MOF-525 using solution shearing on a wide range of substrates will be highly useful for implementing these MOFs in sensing and catalytic applications.
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Affiliation(s)
- Prince K Verma
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Connor A Koellner
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Hailey Hall
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Meagan R Phister
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Kevin H Stone
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Asa W Nichols
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Ankit Dhakal
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Earl Ashcraft
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Charles W Machan
- Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Gaurav Giri
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
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3
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Bhawnani RR, Sartape R, Prajapati A, Podupu P, Coliaie P, Nere AN, Singh MR. Percolation-assisted coating of metal-organic frameworks on porous substrates. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2022.121202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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4
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Pourmadadi M, Eshaghi MM, Ostovar S, Shamsabadipour A, Safakhah S, Mousavi MS, Rahdar A, Pandey S. UiO-66 metal-organic framework nanoparticles as gifted MOFs to the biomedical application: A comprehensive review. J Drug Deliv Sci Technol 2022. [DOI: 10.1016/j.jddst.2022.103758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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5
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DeCoster ME, Babaei H, Jung SS, Hassan ZM, Gaskins JT, Giri A, Tiernan EM, Tomko JA, Baumgart H, Norris PM, McGaughey AJH, Wilmer CE, Redel E, Giri G, Hopkins PE. Hybridization from Guest-Host Interactions Reduces the Thermal Conductivity of Metal-Organic Frameworks. J Am Chem Soc 2022; 144:3603-3613. [PMID: 35179895 DOI: 10.1021/jacs.1c12545] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We experimentally and theoretically investigate the thermal conductivity and mechanical properties of polycrystalline HKUST-1 metal-organic frameworks (MOFs) infiltrated with three guest molecules: tetracyanoquinodimethane (TCNQ), 2,3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4-TCNQ), and (cyclohexane-1,4-diylidene)dimalononitrile (H4-TCNQ). This allows for modification of the interaction strength between the guest and host, presenting an opportunity to study the fundamental atomic scale mechanisms of how guest molecules impact the thermal conductivity of large unit cell porous crystals. The thermal conductivities of the guest@MOF systems decrease significantly, by on average a factor of 4, for all infiltrated samples as compared to the uninfiltrated, pristine HKUST-1. This reduction in thermal conductivity goes in tandem with an increase in density of 38% and corresponding increase in heat capacity of ∼48%, defying conventional effective medium scaling of thermal properties of porous materials. We explore the origin of this reduction by experimentally investigating the guest molecules' effects on the mechanical properties of the MOF and performing atomistic simulations to elucidate the roles of the mass and bonding environments on thermal conductivity. The reduction in thermal conductivity can be ascribed to an increase in vibrational scattering introduced by extrinsic guest-MOF collisions as well as guest molecule-induced modifications to the intrinsic vibrational structure of the MOF in the form of hybridization of low frequency modes that is concomitant with an enhanced population of localized modes. The concentration of localized modes and resulting reduction in thermal conductivity do not seem to be significantly affected by the mass or bonding strength of the guest species.
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Affiliation(s)
- Mallory E DeCoster
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Hasan Babaei
- Department of Chemistry and Chemical and Biomolecular Engineering, University of California, Berkeley, Berkeley, California 94720-1462, United States
| | - Sangeun S Jung
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Zeinab M Hassan
- Institute of Functional Interfaces (IF), Karlsruhe Institute of Technology, Karlsruhe 76131, Germany
| | - John T Gaskins
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Ashutosh Giri
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Emma M Tiernan
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - John A Tomko
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Helmut Baumgart
- Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, Virginia 23529, United States
| | - Pamela M Norris
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Alan J H McGaughey
- Department of Mechanical Engineering, Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - Christopher E Wilmer
- Department of Chemical and Petroleum Engineering, Department of Electrical and Computer Engineering, Clinical and Translational Science Institute, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - Engelbert Redel
- Institute of Functional Interfaces (IF), Karlsruhe Institute of Technology, Karlsruhe 76131, Germany
| | - Gaurav Giri
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Patrick E Hopkins
- Department of Mechanical and Aerospace Engineering, Department of Material Science and Engineering, Department of Physics, University of Virginia, Charlottesville, Virginia 22904-4746, United States
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6
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Huelsenbeck L, Jung S, Herrera Del Valle R, Balachandran PV, Giri G. Accelerated HKUST-1 Thin-Film Property Optimization Using Active Learning. ACS APPLIED MATERIALS & INTERFACES 2021; 13:61827-61837. [PMID: 34913674 DOI: 10.1021/acsami.1c20788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
A flow-coating method termed solution shearing has been shown to grow large-area thin films with no void spaces. Attaining full coverage is one of the key prerequisites for the adoption of any metal-organic framework (MOF) thin film for a variety of practical applications, including separation, membranes and sensors. However, the solution-shearing process has multiple discrete and continuous parameters that can be varied, including the metal ion and linker concentrations, solvents, substrate temperature, coating speed, and the number of coating passes. Optimization of these parameters for full coverage is a time-consuming and daunting process due to vast parameter space. Here, we incorporate an active learning approach into the solution-sheared HKUST-1 thin-film-processing parameters to control the coverage and extend the approach to gain control over the thickness. The understanding of high-quality MOF thin-film formation using solution shearing is improved by correlating the processing parameter sets and their corresponding film coverage. A large area and fully covered HKUST-1 thin film with a minimized thickness of 2.2 μm is fabricated by using guidance from active learning. To confirm full coverage, a redox-active molecule, called 7,7,8,8-tetracyanoquinodimethane (TCNQ), is incorporated along with the HKUST-1 thin film. The TCNQ@HKUST-1 thin film with a minimized thickness has the same order of magnitude of electrical conductivity as that of the TCNQ@HKUST-1 thin film created previously while reducing the film thickness by 60%. We show that active learning has the potential to rapidly navigate the vast processing space in multicomponent systems, especially when experiments are expensive and traditional computational models are not readily available for process optimization.
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Affiliation(s)
- Luke Huelsenbeck
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Sangeun Jung
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Roberto Herrera Del Valle
- Department of Material Science and Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Prasanna V Balachandran
- Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Gaurav Giri
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
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7
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Jung S, Verma P, Robinson S, Beyer E, Hall H, Huelsenbeck L, Stone KH, Giri G. Meniscus Guided Coating and Evaporative Crystallization of UiO-66 Metal Organic Framework Thin Films. Ind Eng Chem Res 2021. [DOI: 10.1021/acs.iecr.1c03969] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sangeun Jung
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Prince Verma
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Sean Robinson
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Emily Beyer
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Hailey Hall
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Luke Huelsenbeck
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
| | - Kevin H. Stone
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Gaurav Giri
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904-4746, United States
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8
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Li YH, Yi XH, Li YX, Wang CC, Wang P, Zhao C, Zheng W. Robust Cr(VI) reduction over hydroxyl modified UiO-66 photocatalyst constructed from mixed ligands: Performances and mechanism insight with or without tartaric acid. ENVIRONMENTAL RESEARCH 2021; 201:111596. [PMID: 34224713 DOI: 10.1016/j.envres.2021.111596] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/06/2021] [Accepted: 06/22/2021] [Indexed: 06/13/2023]
Abstract
Hydroxyl modified UiO-66 ((OH)2-UiO-66-X%, X represents the mass content ratio of introduced 2,5-dihydroxyterephthalic acid) was prepared via a solvothermal reaction between zirconium tetrachloride, benzene-1,4-dicarboxylic acid (H2BDC), as well as 2,5-dihydroxyterephthalic acid (H2BDC-(OH)2). It was found that hydroxyl groups can act as the intramolecular hole scavenger to boost the photo-induced charge carrier separation to enhance Cr(VI) reduction. The photocatalytic Cr(VI) reduction activities of (OH)2-UiO-66-X% were investigated upon the irradiation of low-power ultraviolet LED light. The findings demonstrated that (OH)2-UiO-66-20% with good cyclicity and stability exhibited superior photocatalytic performances to both UiO-66 and (OH)2-UiO-66. The introduction of hydroxyl groups can also extend the light absorption region to longer wavelength in visible range, which provides possibility for displaying photocatalytic activities under sunlight. The effect of small molecule organic acid (SOAs), pH value, and co-existing inorganic ions on photocatalytic performances of (OH)2-UiO-66-20% were investigated. Tartaric acid (TA) as typical SOAs was introduced to the reaction system to further boost the photocatalytic Cr(VI) reduction via acting as hole scavenger, constructing charge-transfer-complex for quick electron transportation, and producing COO·- radicals. This work opened a new opportunity for modified MOFs for boosted elimination activities for environmental pollutants.
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Affiliation(s)
- Yu-Hang Li
- Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Xiao-Hong Yi
- Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Yu-Xuan Li
- Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Chong-Chen Wang
- Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China.
| | - Peng Wang
- Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Chen Zhao
- Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation, School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Weiwei Zheng
- Department of Chemistry, Syracuse University, Syracuse, NY, 13244, United States
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Jung S, Huelsenbeck L, Hu Q, Robinson S, Giri G. Conductive, Large-Area, and Continuous 7,7,8,8-Tetracyanoquinodimethane@HKUST-1 Thin Films Fabricated Using Solution Shearing. ACS APPLIED MATERIALS & INTERFACES 2021; 13:10202-10209. [PMID: 33605712 DOI: 10.1021/acsami.1c00640] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Most metal-organic frameworks (MOFs) have an insulating nature due to their porosity and redox-inactive organic components. The electrical conductivity of the prototypical MOF, HKUST-1, can be tuned by infiltrating a small-molecule organic semiconductor, 7,7,8,8-tetracyanoquinodimethane (TCNQ), into the HKUST-1 pores, creating TCNQ@HKUST-1. However, current processes of creating TCNQ@HKUST-1 films have many roadblocks such as slow crystallization rates, which limit high throughput production, and the formation of Cu(TCNQ) as a byproduct, which affects the electrical conductivity and degrades the chemical structure of HKUST-1. In this work, we show that HKUST-1 films can be rapidly synthesized over large areas with consistent thickness and no pinholes via a meniscus-guided coating technique called solution shearing. The subsequent pore activation process and TCNQ impregnation can be completed via solvent exchange to minimize the formation of the Cu(TCNQ) byproduct, and we obtain an increase in electrical conductivity of the solution-sheared TCNQ@HKUST-1 thin films of over 7 orders of magnitude, reaching a maximum value of 2.42 × 10-2 S m-1 when TCNQ is incorporated for 10 days. The conductivity of solution-sheared TCNQ@HKUST-1 is higher compared to films formed by high-pressure pelletization of TCNQ@HKUST-1. We show that solution shearing can produce large-area thin films rapidly and reduce the formation of grain boundaries better than pelletization, allowing for large-area electronics with both charge transport and porosity for applications as sensors and electronics.
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Affiliation(s)
- Sangeun Jung
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Luke Huelsenbeck
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Qikun Hu
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, People's Republic of China
| | - Sean Robinson
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
| | - Gaurav Giri
- Department of Chemical Engineering, University of Virginia, Charlottesville, Virginia 22904, United States
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da Trindade LG, Borba KM, Trench AB, Zanchet L, Teodoro V, Pontes FM, Longo E, Mazzo TM. Effective strategy to coupling Zr-MOF/ZnO: Synthesis, morphology and photoelectrochemical properties evaluation. J SOLID STATE CHEM 2021. [DOI: 10.1016/j.jssc.2020.121794] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Abstract
AbstractMetal-organic frameworks (MOFs) have emerged as a class of promising membrane materials. UiO-66 is a prototypical and stable MOF material with a number of analogues. In this article, we review five approaches for fabricating UiO-66 polycrystalline membranes including in situ synthesis, secondary synthesis, biphase synthesis, gas-phase deposition and electrochemical deposition, as well as their applications in gas separation, pervaporation, nanofiltration and ion separation. On this basis, we propose possible methods for scalable synthesis of UiO-66 membranes and their potential separation applications in the future.
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12
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Modulating and Orienting an Anisotropic Zn-Based Metal Organic Framework for Selective CH4/CO2 Gas Separation. CRYSTALS 2018. [DOI: 10.3390/cryst9010020] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This work investigates the morphological control of the anisotropic [Zn2(NDC)2(DABCO)]n MOF (Metal organic framework) and the subsequent adsorption characteristics for CO2/CH4 gas separation. Morphology of the MOF crystals is controlled by the use of modulators. The addition of acetic acid or pyridine successfully produce rod or plate morphologies, respectively, with each morphology possessing a different major surface pore aperture. Single-component equilibrium and kinetic adsorption data for CO2 and CH4 were collected. Equilibrium analysis indicates a slight selectivity towards CO2 whereas kinetic data unexpectedly shows lower diffusion time constants for CO2 compared to CH4. Mass transfer resistances on each species is discussed. Finally, a coating technique termed solution shearing is used to orient different morphologies on substrates as a film. An increase in film orientation is observed for the rod morphology, indicating that this MOF morphology is a promising candidate to create large area, thin-film applications.
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