We screen a database of more than 69 000 hypothetical covalent organic frameworks (COFs) for carbon capture using parasitic energy as a metric. To compute CO2–framework interactions in molecular ...simulations, we develop a genetic algorithm to tune the charge equilibration method and derive accurate framework partial charges. Nearly 400 COFs are identified with parasitic energy lower than that of an amine scrubbing process using monoethanolamine; more than 70 are better performers than the best experimental COFs and several perform similarly to Mg-MOF-74. We analyze the effect of pore topology on carbon capture performance to guide the development of improved carbon capture materials.
We present force fields developed from periodic density functional theory (DFT) calculations that can be used in classical molecular simulations to model M–MOF-74 (M = Co, Fe, Mg, Mn, Ni, Zn) and its ...extended linker analogs. Our force fields are based on cationic dummy models (CDMs). These dummy models simplify the methodology required to tune the parameters and improve the accuracy of the force fields. We used our force fields to compare mechanical properties across the M–MOF-74 series and determine that increasing the size of the linker decreases the framework rigidity. In addition, we applied our force fields to an extended linker analog of Mg–MOF-74 and characterized the free energy of a previously reported deformation pattern in which the one-dimensional hexagonal channels of the framework become irregular. The free energy profiles confirm that the deformation is adsorbate induced and impossible to access solely by a pressure stimulus. On the basis of our results, we conclude that the force fields presented here and others that may be developed using our methodology are transferable across metal–organic framework series that share a metal center topology. Finally, we believe that these force fields have the potential to be adapted for the study of complex problems in MOF chemistry, including defects and crystal growth, that have thus far been beyond the scope of classical molecular simulations.
We synthesized two isoreticular furan-based metal–organic frameworks (MOFs), MOF-LA2-1(furan) and MOF-LA2-2(furan) with rod-like secondary building units (SBUs) featuring 1D channels, as sorbents ...for atmospheric water harvesting (LA = long arm). These aluminum-based MOFs demonstrated a combination of high water uptake and stability, exhibiting working capacities of 0.41 and 0.48 gwater/gMOF (under isobaric conditions of 1.70 kPa), respectively. Remarkably, both MOFs showed a negligible loss in water uptake after 165 adsorption–desorption cycles. These working capacities rival that of MOF-LA2-1(pyrazole), which has a working capacity of 0.55 gwater/gMOF. The current MOFs stand out for their high water stability, as evidenced by 165 cycles of water uptake and release. MOF-LA2-2(furan) is the first aluminum MOF to employ a double ‘long arm’ extension strategy, which is confirmed through single-crystal X-ray diffraction (SCXRD). The MOFs were synthesized by using a straightforward synthesis route. This study offers valuable insights into the design of durable, water-stable MOFs and underscores their potential for efficient water harvesting.
We construct a data set of metal–organic framework (MOF) linkers and employ a fine-tuned GPT assistant to propose MOF linker designs by mutating and modifying the existing linker structures. This ...strategy allows the GPT model to learn the intricate language of chemistry in molecular representations, thereby achieving an enhanced accuracy in generating linker structures compared with its base models. Aiming to highlight the significance of linker design strategies in advancing the discovery of water-harvesting MOFs, we conducted a systematic MOF variant expansion upon state-of-the-art MOF-303 utilizing a multidimensional approach that integrates linker extension with multivariate tuning strategies. We synthesized a series of isoreticular aluminum MOFs, termed Long-Arm MOFs (LAMOF-1 to LAMOF-10), featuring linkers that bear various combinations of heteroatoms in their five-membered ring moiety, replacing pyrazole with either thiophene, furan, or thiazole rings or a combination of two. Beyond their consistent and robust architecture, as demonstrated by permanent porosity and thermal stability, the LAMOF series offers a generalizable synthesis strategy. Importantly, these 10 LAMOFs establish new benchmarks for water uptake (up to 0.64 g g–1) and operational humidity ranges (between 13 and 53%), thereby expanding the diversity of water-harvesting MOFs.
We are currently witnessing the dawn of hydrogen (H2) economy, where H2 will soon become a primary fuel for heating, transportation, and long-distance and long-term energy storage. Among diverse ...possibilities, H2 can be stored as a pressurized gas, a cryogenic liquid, or a solid fuel via adsorption onto porous materials. Metal–organic frameworks (MOFs) have emerged as adsorbent materials with the highest theoretical H2 storage densities on both a volumetric and gravimetric basis. However, a critical bottleneck for the use of H2 as a transportation fuel has been the lack of densification methods capable of shaping MOFs into practical formulations while maintaining their adsorptive performance. Here, we report a high-throughput screening and deep analysis of a database of MOFs to find optimal materials, followed by the synthesis, characterization, and performance evaluation of an optimal monolithic MOF (monoMOF) for H2 storage. After densification, this monoMOF stores 46 g L–1 H2 at 50 bar and 77 K and delivers 41 and 42 g L–1 H2 at operating pressures of 25 and 50 bar, respectively, when deployed in a combined temperature–pressure (25–50 bar/77 K → 5 bar/160 K) swing gas delivery system. This performance represents up to an 80% reduction in the operating pressure requirements for delivering H2 gas when compared with benchmark materials and an 83% reduction compared to compressed H2 gas. Our findings represent a substantial step forward in the application of high-density materials for volumetric H2 storage applications.
Carbon dioxide (CO
2
) is both a primary contributor to global warming and a major industrial impurity. Traditional approaches to carbon capture involve corrosive and energy-intensive processes such ...as liquid amine absorption. Although adsorptive separation has long been a promising alternative to traditional processes, up to this point there has been a lack of appropriate adsorbents capable of capturing CO
2
whilst maintaining low regeneration energies. In the context of CO
2
capture, metal-organic frameworks (MOFs) have gained much attention in the past two decades as potential materials. Their tuneable nature allows for precise control over the pore size and chemistry, which allows for the tailoring of their properties for the selective adsorption of CO
2
. While many candidate materials exist, the amount of research into material shaping for use in industrial processes has been limited. Traditional shaping strategies such as pelletisation involve the use of binders and/or mechanical processes, which can have a detrimental impact on the adsorption properties of the resulting materials or can result in low-density structures with low volumetric adsorption capacities. Herein, we demonstrate the use of a series of monolithic MOFs (
mono
UiO-66,
mono
UiO-66-NH
2
&
mono
HKUST-1) for use in gas separation processes.
The use of metal-organic frameworks (MOFs) in industry has been limited due to a lack of shaping technologies. Monolithic MOFs (monoMOFs) offer a viable alternative to traditional shaping offering high density materials for adsorption processes.
The development of effective catalysts is one of the big challenges associated with a new circular carbon economy addressing climate change. The targeted synthesis of robust and recyclable catalysts ...can be made possible through elucidation of the molecular interactions between the active sites in metal–organic frameworks (MOFs) with potentially reactive molecules. Herein, we present the use of lanthanide (Ln)-based MOFs – Ln(HTCPB) Ln: Ce, Nd, Sm, Eu, Tb, and Dy; H4TCPB: 1,2,4,5-tetrakis(4-carboxyphenyl)benzene – as catalysts for the conversion of CO2 to value-added products. Using these MOFs, we describe the fixation of CO2 into the epoxy ring of propylene oxide for the production of cyclic carbonates. Structural analysis of the propylene oxide (PO)-loaded MOF revealed the binding of PO to Ce3+, confirming the key role of open Ce3+ sites in reducing the activation energy of the PO chemical transformation. The ring-opening of the PO molecule is followed by the insertion of one molecule of CO2, leading to the formation of the propylene carbonate (PC) molecule. The channels present in the MOF structure allow for diffusion of CO2 from the environment to the open Ce3+ sites and that of PC in the opposite direction, thus upholding the catalytic process. Ce(HTCPB) exhibited high catalytic activity toward PC production with a turn-over frequency (TOF) = 20.2 h−1, one of the highest reported. The catalyst showed no catalytic deterioration after three cycles and maintained a comparable catalytic activity when aqueous-rich conditions and gas CO2/N2 and CO2/CH4 mixtures were used, highlighting that non-contributing gas molecules or impurities do not affect the catalytic activity of the MOF. Catalytic experiments using Ln(HTCPB) demonstrated that the rate of CO2 conversion decreased by decreasing the ionic radii of the Ln used. Grand canonical Monte Carlo simulations (GCMC) and topographic steric maps suggested that the activity of a catalyst can be tuned by manipulating the ionic size and partial charge of the lanthanides, and steric properties of the active site. Our study highlights the engineering of efficient catalysts capable of converting CO2 into value-added products directly from its wet and mixed-composition streams (e.g., waste flue gas and biogas).
Metal-organic frameworks (MOFs) have emerged as a potential platform for biomedical applications due to their highly tunable porosities, structural diversity, and multi-functionality. MOFs’ external ...surface modifications endow them with new properties and functions, such as hydrophilicity, colloidal stability, controlled payload release, specific targeted delivery, and biocompatibility. These attributes greatly improve the performance and use of MOFs for the diagnosis and treatment of several diseases. In this review, we aim to offer an up-to-date and comprehensive assessment of current advances in the development of surface functionalization of MOFs, from design to application. This review summarizes current surface engineering approaches, highlighting the representative examples of MOFs’ successful modifications for healthcare applications. Finally, we discuss the remaining challenges and limitations of the field while highlighting foresighted ideas and future research directions.
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Advancing health and extending life requires novel therapeutics. MOFs have emerged as an attractive platform in preclinical applications due to their high porosity and exceptional tunability. However, MOFs in nanomedicine face limitations such as high cytotoxicity, poor stability, nonspecific distribution, low cellular uptake, and premature payload release. An attainable solution involves the incorporation of functional molecules onto the external surface of MOFs, conferring them a range of novel capabilities such as enhanced chemical and colloidal stability, improved biocompatibility, controlled payload release, targeted treatment, and responsiveness to specific stimuli. These attributes collectively enhance MOFs’ performance and capability for diagnosing and therapy of various diseases. This review offers an up-to-date assessment of the advancements in external surface functionalization of MOFs, spanning from the initial design stage to their benefits in practical applications.
External surface modification presents a promising approach for introducing novel properties and functions into MOFs. This review examines recent advancements in the external surface modification of MOFs for biomedical applications. It highlights representative surface-coating molecules, emphasizing benefits and limitations while addressing current challenges and future prospects in this field.
The development of effective catalysts is one of the big challenges associated with a new circular carbon economy addressing climate change. The targeted synthesis of robust and recyclable catalysts ...can be made possible through elucidation of the molecular interactions between the active sites in metal-organic frameworks (MOFs) with potentially reactive molecules. Herein, we present the use of lanthanide (Ln)-based MOFs - Ln(HTCPB) Ln: Ce, Nd, Sm, Eu, Tb, and Dy; H
4
TCPB: 1,2,4,5-tetrakis(4-carboxyphenyl)benzene - as catalysts for the conversion of CO
2
to value-added products. Using these MOFs, we describe the fixation of CO
2
into the epoxy ring of propylene oxide for the production of cyclic carbonates. Structural analysis of the propylene oxide (PO)-loaded MOF revealed the binding of PO to Ce
3+
, confirming the key role of open Ce
3+
sites in reducing the activation energy of the PO chemical transformation. The ring-opening of the PO molecule is followed by the insertion of one molecule of CO
2
, leading to the formation of the propylene carbonate (PC) molecule. The channels present in the MOF structure allow for diffusion of CO
2
from the environment to the open Ce
3+
sites and that of PC in the opposite direction, thus upholding the catalytic process. Ce(HTCPB) exhibited high catalytic activity toward PC production with a turn-over frequency (TOF) = 20.2 h
−1
, one of the highest reported. The catalyst showed no catalytic deterioration after three cycles and maintained a comparable catalytic activity when aqueous-rich conditions and gas CO
2
/N
2
and CO
2
/CH
4
mixtures were used, highlighting that non-contributing gas molecules or impurities do not affect the catalytic activity of the MOF. Catalytic experiments using Ln(HTCPB) demonstrated that the rate of CO
2
conversion decreased by decreasing the ionic radii of the Ln used. Grand canonical Monte Carlo simulations (GCMC) and topographic steric maps suggested that the activity of a catalyst can be tuned by manipulating the ionic size and partial charge of the lanthanides, and steric properties of the active site. Our study highlights the engineering of efficient catalysts capable of converting CO
2
into value-added products directly from its wet and mixed-composition streams (
e.g.
, waste flue gas and biogas).
The development of effective catalysts is one of the big challenges associated with a new circular carbon economy addressing climate change.
The development of effective catalysts is one of the big challenges associated with a new circular carbon economy addressing climate change. The targeted synthesis of robust and recyclable catalysts ...can be made possible through elucidation of the molecular interactions between the active sites in metal–organic frameworks (MOFs) with potentially reactive molecules. Herein, we present the use of lanthanide (Ln)-based MOFs – Ln(HTCPB) Ln: Ce, Nd, Sm, Eu, Tb, and Dy; H 4 TCPB: 1,2,4,5-tetrakis(4-carboxyphenyl)benzene – as catalysts for the conversion of CO 2 to value-added products. Using these MOFs, we describe the fixation of CO 2 into the epoxy ring of propylene oxide for the production of cyclic carbonates. Structural analysis of the propylene oxide (PO)-loaded MOF revealed the binding of PO to Ce 3+ , confirming the key role of open Ce 3+ sites in reducing the activation energy of the PO chemical transformation. The ring-opening of the PO molecule is followed by the insertion of one molecule of CO 2 , leading to the formation of the propylene carbonate (PC) molecule. The channels present in the MOF structure allow for diffusion of CO 2 from the environment to the open Ce 3+ sites and that of PC in the opposite direction, thus upholding the catalytic process. Ce(HTCPB) exhibited high catalytic activity toward PC production with a turn-over frequency (TOF) = 20.2 h −1 , one of the highest reported. The catalyst showed no catalytic deterioration after three cycles and maintained a comparable catalytic activity when aqueous-rich conditions and gas CO 2 /N 2 and CO 2 /CH 4 mixtures were used, highlighting that non-contributing gas molecules or impurities do not affect the catalytic activity of the MOF. Catalytic experiments using Ln(HTCPB) demonstrated that the rate of CO 2 conversion decreased by decreasing the ionic radii of the Ln used. Grand canonical Monte Carlo simulations (GCMC) and topographic steric maps suggested that the activity of a catalyst can be tuned by manipulating the ionic size and partial charge of the lanthanides, and steric properties of the active site. Our study highlights the engineering of efficient catalysts capable of converting CO 2 into value-added products directly from its wet and mixed-composition streams ( e.g. , waste flue gas and biogas).
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