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Metal-organic frameworks (MOFs) are a rapidly growing class of materials that offer great promise in various applications. However, the synthesis remains challenging: for example, a range of crystal structures can often be accessed from the same building blocks, which complicates the phase selectivity. Likewise, the high sensitivity to slight changes in synthesis conditions may cause reproducibility issues. This is crucial, as it hampers the research and commercialization of affected MOFs. Here, it presents the first-ever interlaboratory study of the synthetic reproducibility of two Zr-porphyrin MOFs, PCN-222 and PCN-224, to investigate the scope of this problem. For PCN-222, only one sample out of ten was phase pure and of the correct symmetry, while for PCN-224, three are phase pure, although none of these show the spatial linker order characteristic of PCN-224. Instead, these samples resemble dPCN-224 (disordered PCN-224), which has recently been reported. The variability in thermal behavior, defect content, and surface area of the synthesised samples are also studied. The results have important ramifications for field of metal-organic frameworks and their crystallization, by highlighting the synthetic challenges associated with a multi-variable synthesis space and flat energy landscapes characteristic of MOFs. It performed an interlaboratory study of the synthesis of the metal-organic frameworks (MOFs) PCN-222 and PCN-224. Ten participants independently synthesized the two MOFs and the products are analyzed, primarily by X-ray diffraction. The success rates are low (one-three samples corresponding to a pure sample of the correct phase), thus highlighting the problems with irreproducibility in MOF synthesis. image

Metallocene immobilization onto a solid support helps to overcome the drawbacks of homogeneous metallocene complexes in the catalytic olefin polymerization. In this study, valuable insights have been obtained into the effects of pore size, linker composition, and surface groups of metal–organic frameworks (MOFs) on their role as support materials for metallocene-based ethylene polymerization catalysis. Three distinct Zn-based metal–organic frameworks (MOFs), namely, MOF-5, IRMOF-3, and ZIF-8, with different linkers have been activated with methylaluminoxane (MAO) and zirconocene complexes, followed by materials characterization and testing for ethylene polymerization. Characterization has been performed by multiple analytical tools, including X-ray diffraction (XRD), scanning electron microscopy (SEM), gel permeation chromatography (GPC), differential scanning calorimetry (DSC), and CO Fourier transform infrared (FT-IR) spectroscopy. It was found that the interactions between MOFs, MAO, and the zirconocene complex not only lead to both catalyst activation and deactivation but also result in the creation of multiple active sites. By alteration of the MOF support, it is possible to obtain polyethylene with different properties. Notably, ultrahigh molecular weight polyethylene (UHMWPE, MW = 5.34 × 106) was obtained using IRMOF-3 as support. This study reveals the potential of MOF materials as tunable porous supports for metallocene catalysts active in ethylene polymerization.

Detecting traces of phosphates in water is critical for monitoring water quality in aquatic ecosystems. Mid-infrared techniques are effective for label-free and quick measurements in at-line or in-line applications, but sensitivity is limited due to high water absorption. To combat this, preconcentration schemes combined with evanescent field spectroscopy can be used to enrich the analyte in the probed volume and thereby increasing sensitivity. Metal-organic frameworks (MOFs) are versatile materials with defined porosity and tuneable chemistry, which make them ideal for selective adsorption of target molecules. In this study, an NH2-MIL-88B(Fe) (= Fe3O(NH2-BDC)3) MOF-based enrichment layer was prepared on a diamond attenuated total reflection (ATR) crystal for in situ Fourier transform infrared (FTIR) spectroscopic measurements of ortho-phosphates in water. A workflow for single-use enrichment layers was established, and an automated flow system was used to apply aqueous phosphate solutions. Using internal referencing and compensating for variation in MOF film depositions, phosphate analysis reproducibility increased from 74% to 94%. The Langmuir adsorption model was used to derive a limit of detection (LOD) of 0.18 mg L-1 phosphorus in water. Overall, this work demonstrates the effectiveness of NH2-MIL-88B(Fe) MOFs as enrichment layers for aqueous phosphate sensing. Our results provide a promising avenue for the development of sensitive and selective sensors for environmental and biomedical applications.

The intensifying global opioid crisis, majorly attributed to fentanyl (FT) and its analogs, has necessitated the development of rapid and ultrasensitive remote/on-site FT sensing modalities. However, current approaches for tracking FT exposure through wastewater-based epidemiology (WBE) are unadaptable, time-consuming, and require trained professionals. Toward developing an extended in situ wastewater opioid monitoring system, we have developed a screen-printed electrochemical FT sensor and integrated it with a customized submersible remote sensing probe. The sensor composition and design have been optimized to address the challenges for extended in situ FT monitoring. Specifically, ZIF-8 metal-organic framework (MOF)-derived mesoporous carbon (MPC) nanoparticles (NPs) are incorporated in the screen-printed carbon electrode (SPCE) transducer to improve FT accumulation and its electrocatalytic oxidation. A rapid (10 s) and sensitive square wave voltammetric (SWV) FT detection down to 9.9 µgL-1 is thus achieved in aqueous buffer solution. A protective mixed-matrix membrane (MMM) has been optimized as the anti-fouling sensor coating to mitigate electrode passivation by FT oxidation products and enable long-term, intermittent FT monitoring. The unique MMM, comprising an insulating polyvinyl chloride (PVC) matrix and carboxyl-functionalized multi-walled carbon nanotubes (CNT-COOH) as semiconductive fillers, yielded highly stable FT sensor operation (> 95% normalized response) up to 10 h in domestic wastewater, and up to 4 h in untreated river water. This sensing platform enables wireless data acquisition on a smartphone via Bluetooth. Such effective remote operation of submersible opioid sensing probes could enable stricter surveillance of community water systems toward timely alerts, countermeasures, and legal enforcement.

The combination of compositional versatility and topological diversity for the integration of electroactive species into high-porosity molecular architectures is perhaps one of the main appeals of metal–organic frameworks (MOFs) in the field of electrocatalysis. This premise has attracted much interest in recent years, and the results generated have also revealed one of the main limitations of molecular materials in this context: low stability under electrocatalytic conditions. Using zirconium MOFs as a starting point, in this work, we use this stability as a variable to discriminate between the most suitable electrocatalytic reaction and specific topologies within this family. Our results revealed that the PCN-224 family is particularly suitable for the electroreduction of molecular nitrogen for the formation of ammonia with faradaic efficiencies above 30% in the presence of Ni2+ sites, an activity that improves most of the catalysts described. We also introduce the fluorination of porphyrin at the meso position as a good alternative to improve both the activity and stability of this material under electrocatalytic conditions.

Thin-film fluorescent sensors play critical roles in the gas sensing field. However, fluorescent sensing materials for practical applications are limited, because of the aggregation-caused quenching (ACQ) effect and photobleaching. This study investigates a host–guest thin-film fluorescence sensor by incorporating a fluorescent probe into a metal–organic framework (MOF). The fluorescent molecule Me4BOPHY-1 acts as a recognition probe for the neurotoxin analog diethylchlorophosphite (DCP). The MOF (ZIF-8) provides nanocavities for the confinement of guest molecules, which reduces the self-aggregation of fluorescent molecules and pre-enriches the target gas. By applying ZIF-8 framework to disperse the fluorescent molecules, the ACQ effect of Me4BOPHY-1 can be effectively overcome. The fluorescence quantum efficiency of the molecules is increased from 0.76% to 19.72%, which enables its ability for gas sensing with a fast response time of 3 s and a detection limit as low as 1.13 ppb. Besides, the MOF facilitates selectivity enhancement through the confinement effect, weakening the sensing response to the interference of HCl. Moreover, the confinement effect also ensures high photo-stability as well as thermal stability. It can maintain fluorescence intensity under 4800 s’ laser irradiation. Thus, the host–guest design strategy offers a thin-film fluorescence gas sensor with high 3S (sensitivity, selectivity, and stability) toward neurotoxin analytes. © 2024 Wiley-VCH GmbH.

Structural lithium batteries integrated with energy storage and mechanical load-bearing capabilities hold great promise to revolutionize lightweight transport vehicles. However, the current development of structural batteries faces critical challenges in balancing the electrochemical and mechanical properties of the electrolytes. Herein, a super strong quasi-solid composite polymer electrolyte (QCPE) is successfully fabricated by reinforcing polyelectrolyte with 3D in situ self-assembled metal-organic framework-modified glass fiber (MOF@GF) soaking a small amount of liquid electrolyte, which provides continuous ion conductive pathways for fast Li+ transport and contributes to the high ambient ionic conductivity of 1.47 x 10-3 S cm-1. The micropores and abundant polar functional groups selectively restrict the transport of anions to afford a homogeneous Li+ flux and a high Li+ transference number (0.56). Simultaneously, the MOF@GF provides more effective reinforcement and a remarkably high tensile strength of 48.6 MPa, and Young's modulus of 1.66 GPa is achieved. Furthermore, the lithium metal batteries fabricated with this QCPE exhibit a long, stable operation lifespan of 2000 h and excellent cycling performance with LiFePO4 and NCM811 cathodes. This design strategy generally opens a new avenue for structural batteries with high ionic conductivity and outstanding mechanical properties, which holds great promise for industrial translation. A super strong quasi-solid composite polymer electrolyte with excellent ionic conductivity is successfully designed and fabricated by reinforcing polyelectrolyte with 3D in situ self-assembled metal-organic framework-modified glass fiber (MOF@GF). The MOF@GF enhances Li+ transport and mechanical strength, showcasing promise for structural batteries with superior ionic conductivity and mechanical properties in industrial applications.image (c) 2024 WILEY-VCH GmbH

Interactions among biomacromolecules, predominantly noncovalent, underpin biological processes. However, recent advancements in biospecific chemistry have enabled the creation of specific covalent bonds between biomolecules, both in vitro and in vivo. This Review traces the evolution of biospecific chemistry in proteins, emphasizing the role of genetically encoded latent bioreactive amino acids. These amino acids react selectively with adjacent natural groups through proximity-enabled bioreactivity, enabling targeted covalent linkages. We explore various latent bioreactive amino acids designed to target different protein residues, ribonucleic acids, and carbohydrates. We then discuss how these novel covalent linkages can drive challenging protein properties and capture transient protein-protein and protein-RNA interactions in vivo. Additionally, we examine the application of covalent peptides as potential therapeutic agents and site-specific conjugates for native antibodies, highlighting their capacity to form stable linkages with target molecules. A significant focus is placed on proximity-enabled reactive therapeutics (PERx), a pioneering technology in covalent protein therapeutics. We detail its wide-ranging applications in immunotherapy, viral neutralization, and targeted radionuclide therapy. Finally, we present a perspective on the existing challenges within biospecific chemistry and discuss the potential avenues for future exploration and advancement in this rapidly evolving field.

Metall-organische Gerüstverbindungen (MOFs) sind kristalline Hybridmaterialien, die durch die Verknüpfung anorganischer Baueinheiten und organischen Linkermolekülen entstehen. MOFs sind meist hochporöse Materialien, die als Pulver, Einkristalle, Nanopartikel, Oberflächenbeschichtungen und in vielen anderen Formen hergestellt werden können. Der modulare Aufbau erlaubt es, ihre Eigenschaften für die gewünschte Anwendung anzupassen. Diese Arbeit beschäftigt sich mit einer wichtigen Untergruppe der MOFs, den Zeolith-analogen Gerüstverbindungen (ZIFs). Der Fokus liegt auf der Herstellung substratgebundener ZIF-Dünnfilme in hoher optischer Qualität und deren Anwendung für die Brechungsindexmodulation. Im ersten Teil dieser Arbeit wird eine detaillierte Machbarkeitsstudie dargelegt, in der Dünnfilme der Gerüstverbindung ZIF 8, einer der bekanntesten und am besten untersuchten ZIFs, als Modellsystem verwendet werden. Der Brechungsindex von ZIF 8 kann durch Adsorption unterschiedlicher Gastmoleküle in seine Poren eingestellt werden. Sowohl statische als auch reversible, dynamische Brechungsindexänderungen können induziert werden, indem Gastmoleküle über die Flüssig- oder Gasphase in die MOF-Poren eingelagert werden. Der zweite Teil dieser Arbeit beschäftigt sich mit Beschichtungen von ZIFs auf anderen ZIFs. ZIF 8 und Co ZIF 90 werden als Modellsystem verwendet. Co ZIF 90-Dünnfilme mit optischer Qualität können nicht direkt auf ein Substrat beschichtet werden, da Co-ZIF-90 in Lösung Mikrokristalle bildet, wodurch das Filmwachstum ausbleibt. Durch Vorbeschichtung eines Substrats mit einem dünnen ZIF-8 Film wurde die Bildung von Co ZIF-90 Dünnfilmen optischer Qualität ermöglicht. Die Kristallisation von Co ZIF 90 wird mit Hilfe eines neuen Ansatzes kontrolliert, bei dem Metallsalze des gleichen Metalls in definierten Mengen gemischt werden, wodurch sich die Kristallisationsgeschwindigkeit des MOFs steuern lässt. Der Brechungsindex von Co ZIF 90 lässt sich reversibel durch die A, Metal-organic frameworks (MOFs) are crystalline hybrid materials built up from inorganic building units and organic linker molecules. Most MOFs are highly porous materials that can be synthesized as powders, single crystals, nanoparticles, surface coatings, and in many other shapes. Their modular design allows for adjusting their properties on the desired application. This thesis deals with an important subclass of MOFs, the zeolitic imidazolate frameworks (ZIFs). The focus is on the fabrication of substrate-supported ZIF thin films of high optical quality and the characterization of their refractive index modulation ability. In the first part, a detailed proof-of-principle study on thin films of ZIF 8, which is one of the most popular and best investigated ZIFs and that acts as a model system in this thesis, is presented. The refractive index of ZIF 8 can be modulated by the adsorption of a variety of guest molecules into its pores. Static refractive index modulation as well as reversible, dynamic refractive index switching can be performed by adsorption of guest molecules via the liquid or gas phase. The second part of this thesis deals with ZIF-on-ZIF coatings. ZIF 8 and Co-ZIF-90 are used as the model system. Co ZIF 90 thin film of optical quality cannot be coated directly on a substrate because of the heterogeneous formation of microcrystals in solution that avoids film formation. By precoating a substrate with a ZIF 8 seeding layer, formation of Co-ZIF-90 thin films of optical quality was achieved. The crystallization of Co ZIF 90 is promoted by mixing different metal salts of the same metal in defined ratios which allows controlling the crystallization speed of the MOF. Refractive index modulation in Co ZIF 90 can be performed fast and reversibly by the adsorption of water from the environment when the relative humidity of a gas flow is changed. These approaches were further used in a third publication describing the formation of alternated and mixed stacks o

Due to their modular design from inorganic building units (IBUs) and organic linker molecules, metal-organic frameworks (MOFs) exhibit great flexibility and variability in terms of their inherent properties. However, the creation of MOF-based electronic and optoelectronic devices, suitable for real-world applications, critically depends on the availability of highly adaptable materials, that can be patterned down to the nanometer scale. MOFs based on the linker benzophenone dicarboxylate (bzpdc) present a promising platform in this regard: They allow for the photochemical integration of almost any functionality into their frameworks through easily accessible postsynthetic modifications (PSMs). While this approach has been limited to powdered bulk materials so far, transitioning to more processable forms such as membranes or thin films is now crucial for their integration into practical applications. Light, the key initiator of the reaction, can be manipulated in various ways to create spatially resolved selective structures within bzpdc-MOFs. The PhD thesis presented here, addresses this issue and can be thematically divided into two main areas. The first section covers the shaping of a zirconium-based bzpdc-MOF for applications extending to 3D micropatterning. The second section of the PhD thesis is dedicated to the development of a novel, multifunctional bzpdc-MOF.

Metal-organic frameworks (MOFs) are highly versatile materials because of their tunable properties. However, the typically poor electrical conductivity of MOFs presents challenges for their integration into electrical devices. By adding carbon nanotubes to MOF synthesis, a highly intergrown material with increased conductivity and chemiresistive sensing properties can be obtained. Here, we present a patterning technique to control MOF growth on predefined areas of one particular carbon nanotube. We found that electron beam pretreatment of -COOH functionalized multi-walled carbon nanotubes inhibits the growth of UiO-66 MOF on these multi-walled carbon nanotubes. By irradiating individual multi-walled carbon nanotubes, we show that MOF growth can be inhibited in predefined tube areas, creating MOF-free spaces on the nanotube. In this way, our method shows a possibility to pattern MOF growth on individual nanotubes.

We present a new example of rare metal-organic frameworks (MOFs) containing ruthenium inorganic building units (IBUs). Advanced characterization techniques such as three-dimensional electron diffraction and in situ powder X-ray diffraction, performed in parallel with adsorption of various gases and vapors, were used to determine the structure and framework dynamics of [Ru2(bzpdc)(bipy)] (bzpdc = 4,4′-benzophenone dicarboxylate, bipy = 4,4′-bipyridine), revealing unique and highly relevant material features: In the 2D nanoporous framework, ruthenium paddle-wheel IBUs are mixed-valent and provide potential open metal sites. Coupled with the flexible behavior of the framework in the form of specific reversible structural transformations and selective gating upon adsorption of various guests, the material is thus ideally suited for sensing or catalytic applications.

Carbon dioxide (CO2) is present in our atmosphere as the fourth most abundant gas. The non-toxicity and non-flammability of CO2 makes it an attractive C1-synthon in organic synthesis. This thesis aims to develop catalytic transformations to utilize CO2 in the preparation of organic compounds, namely carboxylic acids and cyclic carbonates. The developed methods center around photoredox chemistry, electrochemistry, homogeneous catalysis, and heterogeneous catalysis. Synthesis of carbon-isotope-labeled organic compounds from isotopic CO2 which are of great importance in medicinal chemistry was also presented. Due to the inertness of CO2, activation of either CO2 or other starting materials by photocatalysis or electrocatalysis facilitates the incorporation of CO2 into organic compounds. By using a photoredox catalyst under visible light irradiation, highly reactive carbanions can be formed from common feedstocks, such as sulfinate salts and alkenes. The electron-dense carbanions readily react with 13CO2 to yield 13C-labeled aliphatic carboxylic acids. On the contrary, CO2 can be electrochemically reduced to the more reactive CO, which can readily undergo palladium-catalyzed hydroxycarbonylation with aryl iodides to yield benzoic acids. In this work, tandem reactions based on the use of recyclable heterogeneous catalysis have been developed for this transformation. Epoxides are ring-strained molecules that can undergo cycloaddition reactions with CO2 to yield cyclic carbonates. In this thesis, a stereospecific catalytic approach for accessing 13C- and 14C-labeled chiral cyclic carbonates using near stoichiometric amount of CO2 was developed. The labeled chiral cyclic carbonates serve as precursors for the synthesis of isotope-labeled pharmaceuticals. Furthermore, an auto-relay heterogeneous catalysis approach was developed to obtain epoxides from readily available alkenes in a chemoselective manner, which can further react with CO2 to form cyclic carbonates.

Carbon dioxide (CO2) is present in our atmosphere as the fourth most abundant gas. The non-toxicity and non-flammability of CO2 makes it an attractive C1-synthon in organic synthesis. This thesis aims to develop catalytic transformations to utilize CO2 in the preparation of organic compounds, namely carboxylic acids and cyclic carbonates. The developed methods center around photoredox chemistry, electrochemistry, homogeneous catalysis, and heterogeneous catalysis. Synthesis of carbon-isotope-labeled organic compounds from isotopic CO2 which are of great importance in medicinal chemistry was also presented. Due to the inertness of CO2, activation of either CO2 or other starting materials by photocatalysis or electrocatalysis facilitates the incorporation of CO2 into organic compounds. By using a photoredox catalyst under visible light irradiation, highly reactive carbanions can be formed from common feedstocks, such as sulfinate salts and alkenes. The electron-dense carbanions readily react with 13CO2 to yield 13C-labeled aliphatic carboxylic acids. On the contrary, CO2 can be electrochemically reduced to the more reactive CO, which can readily undergo palladium-catalyzed hydroxycarbonylation with aryl iodides to yield benzoic acids. In this work, tandem reactions based on the use of recyclable heterogeneous catalysis have been developed for this transformation. Epoxides are ring-strained molecules that can undergo cycloaddition reactions with CO2 to yield cyclic carbonates. In this thesis, a stereospecific catalytic approach for accessing 13C- and 14C-labeled chiral cyclic carbonates using near stoichiometric amount of CO2 was developed. The labeled chiral cyclic carbonates serve as precursors for the synthesis of isotope-labeled pharmaceuticals. Furthermore, an auto-relay heterogeneous catalysis approach was developed to obtain epoxides from readily available alkenes in a chemoselective manner, which can further react with CO2 to form cyclic carbonates.

Cellulose-based aerogels are emerging bio-based materials for a range of applications in the quest toward a circular and carbon-neutral society. Owing to their lightweight nature, high porosity, high specific surface area, biocompatibility, and biodegradability, cellulose aerogels are suitable for packaging, insulation, wound care products, hygiene products, and water purification. However, their commercial use is hampered by complicated time- and energy-consuming fabrication processes. Hence, industrially relevant processes with upscaling opportunities need to be developed for cellulose-based aerogels to reach their full potential. This thesis explores different scalable and simple methods for preparing and designing highly porous aerogels with high wet integrity using cellulose-rich fibers and cellulose nanofibrils (CNFs). As wet integrity is crucial for specific applications and enables further functionalization of the aerogels using water-based chemistry, different methods were developed to achieve wet integrity without complicated crosslinking procedures. The effects of the raw materials and processing methods on the final material properties were also carefully studied to optimize the performance for the targeted applications. Moreover, the role of the network-forming ability of CNFs in the development of functional materials with structural integrity was explored by incorporating small amounts of CNFs in aerogel systems based on macroscopic cellulose-rich fibers and nanosized metal-organic frameworks. Finally, the potential of the different developed cellulose-based or cellulose-reinforced aerogels with high wet integrity was demonstrated in applications for which the aerogels’ structural integrity and physical and mechanical properties are highly advantageous, such as biomedical applications, gas storage and separation, flame retardancy, and hygiene products. As demonstrated in this thesis, these functional aerogel materials could be a bio-based alternativ, Cellulosabaserade aerogeler har på senare tid visat sig vara användbara biobaserade material för olika tillämpningar i strävan mot ett cirkulärt och kolneutralt samhälle. Materialens mycket låga densitet, höga porositet, höga specifika yta, biokompatibilitet och biologiska nedbrytbarhet innebär att cellulosaaerogeler är lämpliga för förpackningar, isolering, sårvårdsprodukter, hygienprodukter och vattenrening. Den kommersiella användningen har dock bromsats av komplicerade, tid- och energikrävande tillverkningsmetoder. Därmed måste industriellt relevanta processer med uppskalningsmöjligheter utvecklas för att cellulosabaserade aerogeler ska nå sin fulla potential. Denna avhandling utforskar olika skalbara och enkla metoder för att bereda och skräddarsy högporösa och våtstabila aerogeler från cellulosafibrer och cellulosananofibriller (CNFer). Eftersom våtstabilitet är avgörande för vissa tillämpningar och möjliggör ytterligare funktionalisering med vattenbaserad kemi, har ett omfattande arbete genomförts för att identifiera nya metoder för att skapa en god våtstabilitet utan att använda komplicerade tvärbindningsprocedurer. Ett stort fokus har även lagts på att klarlägga råvarans och bearbetningsmetodernas inverkan på de slutliga materialegenskaperna för att optimera prestandan för riktade tillämpningar. Dessutom har CNFers unika nätverksbildande egenskaper också utforskats i att skapa funktionella material med strukturell integritet från mycket små mängder CNFer i aerogelsystem baserade på makroskopiska cellulosarika fibrer och nanopartiklar av metallorganiska nätverk. Slutligen demonstrerades potentialen av de framställda cellulosabaserade och cellulosaförstärkta aerogelerna med utmärkt våtstyrka i tillämpningar där deras strukturella integritet, fysikaliska och mekaniska egenskaper kan användas på ett mycket fördelaktigt sätt, till exempel biomedicinska applikationer, gaslagring och -separering, flamskydd, och hygienprodukter. Mot bakgrund av dessa resultat är d, QC 20240522Embargo godkänt av skolchef Amelie Eriksson Karlström via e-post 2024-05-14

Porous materials, such as porous carbons (PCs), metal-organic frameworks (MOFs), and covalent organic frameworks (COFs), show considerable potential across various fields because of their rich microporous and mesoporous structures and large surface areas, yet they grapple with challenges like environmentally unfriendly fabrication methods and poor processability. In this thesis, we investigated environmentally friendly fabrication methods for porous materials, nanoengineering techniques for processing these materials, and their potential applications. Cladophora cellulose (CC), a naturally abundant biopolymer, was used to prepare PC via a one-step physical carbonization/activation method without using any corrosive activation agents. The obtained CC-derived PC (CPC) showed a high specific surface area (507.2 m2 g−1) and rich microporous structure. Additionally, we introduced a simple and environmentally friendly method for synthesizing imine-linked COFs at room temperature using water as the solvent. The method involves a key step in which aldehyde monomers are pre-activated by acetic acid, which promotes the aldehyde monomers to dissolve in water, enhancing their reactivity with amine monomers, and ensuring the formation of crystalline COFs. Consequently, we synthesized 16 distinct imine-linked COFs with high crystallinity and specific surface areas. Furthermore, this thesis focusses on improving the poor processability of these materials caused by the infusible and insoluble nature of their powders. The poor processability of these porous materials makes them difficult to process into desired structures and shapes. Here, we introduce two nanoengineering methods: i) Interweaving porous materials with CC nanofibers (CNFs) to form CNF-porous material aqueous solutions; and ii) Interfacial synthesis of porous materials on the surface of carboxylated CNFs to form CNF@porous materials with nanofiber structures in aqueous solutions. The obtained composite suspensions ca

Engineering the building blocks in metal–organic materials is an effective strategy for tuning their dynamical properties and can affect their response to external guest molecules. Tailoring the interaction and diffusion of molecules into these structures is highly important, particularly for applications related to gas separation. Herein, we report a vanadium-based hybrid ultramicroporous material, VOFFIVE-1-Ni, with temperature-dependent dynamical properties and a strong affinity to effectively capture and separate carbon dioxide (CO2) from methane (CH4). VOFFIVE-1-Ni exhibits a CO2 uptake of 12.08 wt % (2.75 mmol g–1), a negligible CH4 uptake at 293 K (0.5 bar), and an excellent CO2-over-CH4 uptake ratio of 2280, far exceeding that of similar materials. The material also exhibits a favorable CO2 enthalpy of adsorption below −50 kJ mol–1, as well as fast CO2 adsorption rates (90% uptake reached within 20 s) that render the hydrolytically stable VOFFIVE-1-Ni a promising sorbent for applications such as biogas upgrading.

Carbon dioxide (CO2) is present in our atmosphere as the fourth most abundant gas. The non-toxicity and non-flammability of CO2 makes it an attractive C1-synthon in organic synthesis. This thesis aims to develop catalytic transformations to utilize CO2 in the preparation of organic compounds, namely carboxylic acids and cyclic carbonates. The developed methods center around photoredox chemistry, electrochemistry, homogeneous catalysis, and heterogeneous catalysis. Synthesis of carbon-isotope-labeled organic compounds from isotopic CO2 which are of great importance in medicinal chemistry was also presented. Due to the inertness of CO2, activation of either CO2 or other starting materials by photocatalysis or electrocatalysis facilitates the incorporation of CO2 into organic compounds. By using a photoredox catalyst under visible light irradiation, highly reactive carbanions can be formed from common feedstocks, such as sulfinate salts and alkenes. The electron-dense carbanions readily react with 13CO2 to yield 13C-labeled aliphatic carboxylic acids. On the contrary, CO2 can be electrochemically reduced to the more reactive CO, which can readily undergo palladium-catalyzed hydroxycarbonylation with aryl iodides to yield benzoic acids. In this work, tandem reactions based on the use of recyclable heterogeneous catalysis have been developed for this transformation. Epoxides are ring-strained molecules that can undergo cycloaddition reactions with CO2 to yield cyclic carbonates. In this thesis, a stereospecific catalytic approach for accessing 13C- and 14C-labeled chiral cyclic carbonates using near stoichiometric amount of CO2 was developed. The labeled chiral cyclic carbonates serve as precursors for the synthesis of isotope-labeled pharmaceuticals. Furthermore, an auto-relay heterogeneous catalysis approach was developed to obtain epoxides from readily available alkenes in a chemoselective manner, which can further react with CO2 to form cyclic carbonates.

Two-dimensional metal–organic nanosheets (MONs) have emerged as attractive alternatives to their three-dimensional metal–organic framework (MOF) counterparts for heterogeneous catalysis due to their greater external surface areas and higher accessibility of catalytically active sites. Zr MONs are particularly prized because of their chemical stability and high Lewis and Brønsted acidities of the Zr clusters. Herein, we show that careful control over modulated self-assembly and exfoliation conditions allows the isolation of the first example of a two-dimensional nanosheet wherein Zr6 clusters are linked by dicarboxylate ligands. The hxl topology MOF, termed GUF-14 (GUF = Glasgow University Framework), can be exfoliated into monolayer thickness hns topology MONs, and acid-induced removal of capping modulator units yields MONs with enhanced catalytic activity toward the formation of imines and the hydrolysis of an organophosphate nerve agent mimic. The discovery of GUF-14 serves as a valuable example of the undiscovered MOF/MON structural diversity extant in established metal–ligand systems that can be accessed by harnessing the power of modulated self-assembly protocols.

Porous materials, such as porous carbons (PCs), metal-organic frameworks (MOFs), and covalent organic frameworks (COFs), show considerable potential across various fields because of their rich microporous and mesoporous structures and large surface areas, yet they grapple with challenges like environmentally unfriendly fabrication methods and poor processability. In this thesis, we investigated environmentally friendly fabrication methods for porous materials, nanoengineering techniques for processing these materials, and their potential applications. Cladophora cellulose (CC), a naturally abundant biopolymer, was used to prepare PC via a one-step physical carbonization/activation method without using any corrosive activation agents. The obtained CC-derived PC (CPC) showed a high specific surface area (507.2 m2 g−1) and rich microporous structure. Additionally, we introduced a simple and environmentally friendly method for synthesizing imine-linked COFs at room temperature using water as the solvent. The method involves a key step in which aldehyde monomers are pre-activated by acetic acid, which promotes the aldehyde monomers to dissolve in water, enhancing their reactivity with amine monomers, and ensuring the formation of crystalline COFs. Consequently, we synthesized 16 distinct imine-linked COFs with high crystallinity and specific surface areas. Furthermore, this thesis focusses on improving the poor processability of these materials caused by the infusible and insoluble nature of their powders. The poor processability of these porous materials makes them difficult to process into desired structures and shapes. Here, we introduce two nanoengineering methods: i) Interweaving porous materials with CC nanofibers (CNFs) to form CNF-porous material aqueous solutions; and ii) Interfacial synthesis of porous materials on the surface of carboxylated CNFs to form CNF@porous materials with nanofiber structures in aqueous solutions. The obtained composite suspensions ca

The series of metal–organic frameworks M-MOF-74 gained popularity in the field of capture and separation of CO2 due to the presence of numerous, highly reactive open-metal sites. The description of effective interactions between guest molecules and open-metal sites without accounting for polarization effects is challenging but it can significantly reduce the computational cost of simulations. In this study, we propose a non-polarizable force field for CO2, and H2 adsorption in M-MOF-74 (M = Ni, Cu, Co, Fe, Mn, Zn) by scaling the Coulombic interactions of M-MOF-74 atoms, and Lennard-Jones interaction potentials between the center of mass of H2 and the open-metal centers. The presented force field is based on UFF and DREIDING parameters, characterized by high transferability and efficiency. The quantum behavior of H2 at cryogenic temperatures is considered by incorporating Feynman–Hibbs quantum corrections. To validate the force field, the experimental isotherms of CO2 at 298 K and 10−1 – 102kPa, the isotherms of H2 at 77 K and 10−5 – 102kPa, the corresponding enthalpy of adsorption, and the binding geometries in the M-MOF-74 series were reproduced using Monte Carlo simulations in the grand-canonical ensemble. The computed loadings, heats of CO2 and H2 adsorption, and binding geometries in M-MOF-74 are in very good agreement with the experimental values. The temperature transferability of the force field from 77 K to 87 K, and 298 K was shown for adsorption of H2. The validated force field was used to study the adsorption and separation of CO2/H2 mixtures at 298 K. The adsorption of H2 practically does not occur when CO2 is present in the mixture. As indicated from simulated breakthrough curves, the breakthrough time of CO2 in M-MOF-74 follows the same order a, Engineering Thermodynamics

The series of metal–organic frameworks M-MOF-74 gained popularity in the field of capture and separation of CO2 due to the presence of numerous, highly reactive open-metal sites. The description of effective interactions between guest molecules and open-metal sites without accounting for polarization effects is challenging but it can significantly reduce the computational cost of simulations. In this study, we propose a non-polarizable force field for CO2, and H2 adsorption in M-MOF-74 (M = Ni, Cu, Co, Fe, Mn, Zn) by scaling the Coulombic interactions of M-MOF-74 atoms, and Lennard-Jones interaction potentials between the center of mass of H2 and the open-metal centers. The presented force field is based on UFF and DREIDING parameters, characterized by high transferability and efficiency. The quantum behavior of H2 at cryogenic temperatures is considered by incorporating Feynman–Hibbs quantum corrections. To validate the force field, the experimental isotherms of CO2 at 298 K and 10−1 – 102kPa, the isotherms of H2 at 77 K and 10−5 – 102kPa, the corresponding enthalpy of adsorption, and the binding geometries in the M-MOF-74 series were reproduced using Monte Carlo simulations in the grand-canonical ensemble. The computed loadings, heats of CO2 and H2 adsorption, and binding geometries in M-MOF-74 are in very good agreement with the experimental values. The temperature transferability of the force field from 77 K to 87 K, and 298 K was shown for adsorption of H2. The validated force field was used to study the adsorption and separation of CO2/H2 mixtures at 298 K. The adsorption of H2 practically does not occur when CO2 is present in the mixture. As indicated from simulated breakthrough curves, the breakthrough time of CO2 in M-MOF-74 follows the same order a

Efficient sequestration of arsenic from drinking water is a global need. Herein we report eco-friendly porous hybrid adsorbent beads for removal of arsenic, through in situ synthesis of MIL-100(Fe) in the chitosan solvogel. To understand the structural vs. performance correlation, series of hybrid adsorbents were synthesized by modulating synthesis conditions like temperature, crystallization time, and concentration. Adsorbents were investigated using PXRD, FT-IR, SEM, and ICP-OES. Intriguing correlation between crystallinity and adsorption performance was observed as low and high crystalline MIL-100(Fe)-chitosan (ChitFe5 and ChitFe7, respectively) exhibited exceptional adsorption towards As5+ by removing it from water with 99% efficiency, whereas for As3+ species removal of about 85% was afforded. Adsorption isotherms indicated that increase in crystallinity (ChitFe5 -> ChitFe7), adsorption capacities of As5+ and As3+ increased from 23.2 to 64.5, and from 28.1 to 35.3 mg/g, respectively. Selectivity tests of the adsorbents towards As5+ and As3+ over competitive anions in the equimolar competitive systems having nitrates, sulfates, and carbonates demonstrated that the performance of the absorbents was fully maintained, relative to the control system. Through this study a highly selective and efficient adsorbent for arsenic species is designed and a clear insight into the structural tuning and its effect on adsorption performance is provided.

Electron-phonon interactions, crucial in condensed matter, are rarely seen in Metal-Organic Frameworks (MOFs). Detecting these interactions typically involves analyzing luminescence in lanthanide- or actinide-based compounds. Prior studies on Ln- and Ac-based MOFs at high temperatures revealed additional peaks, but these were too faint for thorough analysis. In our research, we fabricated a high-quality, crystalline uranium-based MOF (KIT-U-1) thin film using a layer-by-layer method. Under UV light, this film showed two distinct 'hot bands,' indicating a strong electron-phonon interaction. At 77 K, these bands were absent, but at 300 K, a new emission band appeared with half the intensity of the main luminescence. Surprisingly, a second hot band emerged above 320 K, deviating from previous findings in rare-earth compounds. We conducted a detailed ab-initio analysis employing time-dependent density function theory to understand this unusual behaviour and to identify the lattice vibration responsible for the strong electron-phonon coupling. The KIT-U-1 film's hot-band emission was then utilized to create a highly sensitive, single-compound optical thermometer. This underscores the potential of high-quality MOF thin films in exploiting the unique luminescence of lanthanides and actinides for advanced applications.

Natural gas, which mainly consists of methane, is a good fuel for vehicles. Metal-organic frameworks (MOF) have attracted much attention as a new group of adsorbent materials in natural gas storage. MOF structures form various networks by connecting secondary structural units composed of metal ions and organic binders. These regular materials have high porosity and have high design capabilities. This feature has made MOFs suitable for special applications in trapping and absorbing various materials. The investigation of these materials has focused on the absorption of pure methane, although natural gas contains a small amount of larger hydrocarbons such as ethane and propane, which have greater absorption than methane. This Manuscript presents an overview of the current state of the metal-organic framework for methane storage.

Natural gas, which mainly consists of methane, is a good fuel for vehicles. Metal-organic frameworks (MOF) have attracted much attention as a new group of adsorbent materials in natural gas storage. MOF structures form various networks by connecting secondary structural units composed of metal ions and organic binders. These regular materials have high porosity and have high design capabilities. This feature has made MOFs suitable for special applications in trapping and absorbing various materials. The investigation of these materials has focused on the absorption of pure methane, although natural gas contains a small amount of larger hydrocarbons such as ethane and propane, which have greater absorption than methane. This Manuscript presents an overview of the current state of the metal-organic framework for methane storage.

The recent advancements in fabricating forward osmosis (FO) membranes have shown promising results in desalination and water treatment. Different methods have been applied to improve FO performance, such as using mixed or new draw solutions, enhancing the recovery of draw solutions, membrane modification, and developing FO-hybrid systems. However, reliable methods to address the current issues, including reverse salt flux, fouling, and antibacterial activities, are still in progress. In recent decades, surface modification has been applied to different membrane processes, including FO membranes. Introducing nanochannels, bioparticles, new monomers, and hydrophilic-based materials to the surface layer of FO membranes has significantly impacted their performance and efficiency and resulted in better control over fouling and concentration polarization (CP) in these membranes. This review critically investigates the recent developments in FO membrane processes and fabrication techniques for FO surface-layer modification. In addition, this study focuses on the latest materials and structures used for the surface modification of FO membranes. Finally, the current challenges, gaps, and suggestions for future studies in this field have been discussed in detail.

Porous materials, such as porous carbons (PCs), metal-organic frameworks (MOFs), and covalent organic frameworks (COFs), show considerable potential across various fields because of their rich microporous and mesoporous structures and large surface areas, yet they grapple with challenges like environmentally unfriendly fabrication methods and poor processability. In this thesis, we investigated environmentally friendly fabrication methods for porous materials, nanoengineering techniques for processing these materials, and their potential applications. Cladophora cellulose (CC), a naturally abundant biopolymer, was used to prepare PC via a one-step physical carbonization/activation method without using any corrosive activation agents. The obtained CC-derived PC (CPC) showed a high specific surface area (507.2 m2 g−1) and rich microporous structure. Additionally, we introduced a simple and environmentally friendly method for synthesizing imine-linked COFs at room temperature using water as the solvent. The method involves a key step in which aldehyde monomers are pre-activated by acetic acid, which promotes the aldehyde monomers to dissolve in water, enhancing their reactivity with amine monomers, and ensuring the formation of crystalline COFs. Consequently, we synthesized 16 distinct imine-linked COFs with high crystallinity and specific surface areas. Furthermore, this thesis focusses on improving the poor processability of these materials caused by the infusible and insoluble nature of their powders. The poor processability of these porous materials makes them difficult to process into desired structures and shapes. Here, we introduce two nanoengineering methods: i) Interweaving porous materials with CC nanofibers (CNFs) to form CNF-porous material aqueous solutions; and ii) Interfacial synthesis of porous materials on the surface of carboxylated CNFs to form CNF@porous materials with nanofiber structures in aqueous solutions. The obtained composite suspensions ca

Cellulose-based aerogels are emerging bio-based materials for a range of applications in the quest toward a circular and carbon-neutral society. Owing to their lightweight nature, high porosity, high specific surface area, biocompatibility, and biodegradability, cellulose aerogels are suitable for packaging, insulation, wound care products, hygiene products, and water purification. However, their commercial use is hampered by complicated time- and energy-consuming fabrication processes. Hence, industrially relevant processes with upscaling opportunities need to be developed for cellulose-based aerogels to reach their full potential. This thesis explores different scalable and simple methods for preparing and designing highly porous aerogels with high wet integrity using cellulose-rich fibers and cellulose nanofibrils (CNFs). As wet integrity is crucial for specific applications and enables further functionalization of the aerogels using water-based chemistry, different methods were developed to achieve wet integrity without complicated crosslinking procedures. The effects of the raw materials and processing methods on the final material properties were also carefully studied to optimize the performance for the targeted applications. Moreover, the role of the network-forming ability of CNFs in the development of functional materials with structural integrity was explored by incorporating small amounts of CNFs in aerogel systems based on macroscopic cellulose-rich fibers and nanosized metal-organic frameworks. Finally, the potential of the different developed cellulose-based or cellulose-reinforced aerogels with high wet integrity was demonstrated in applications for which the aerogels’ structural integrity and physical and mechanical properties are highly advantageous, such as biomedical applications, gas storage and separation, flame retardancy, and hygiene products. As demonstrated in this thesis, these functional aerogel materials could be a bio-based alternativ, Cellulosabaserade aerogeler har på senare tid visat sig vara användbara biobaserade material för olika tillämpningar i strävan mot ett cirkulärt och kolneutralt samhälle. Materialens mycket låga densitet, höga porositet, höga specifika yta, biokompatibilitet och biologiska nedbrytbarhet innebär att cellulosaaerogeler är lämpliga för förpackningar, isolering, sårvårdsprodukter, hygienprodukter och vattenrening. Den kommersiella användningen har dock bromsats av komplicerade, tid- och energikrävande tillverkningsmetoder. Därmed måste industriellt relevanta processer med uppskalningsmöjligheter utvecklas för att cellulosabaserade aerogeler ska nå sin fulla potential. Denna avhandling utforskar olika skalbara och enkla metoder för att bereda och skräddarsy högporösa och våtstabila aerogeler från cellulosafibrer och cellulosananofibriller (CNFer). Eftersom våtstabilitet är avgörande för vissa tillämpningar och möjliggör ytterligare funktionalisering med vattenbaserad kemi, har ett omfattande arbete genomförts för att identifiera nya metoder för att skapa en god våtstabilitet utan att använda komplicerade tvärbindningsprocedurer. Ett stort fokus har även lagts på att klarlägga råvarans och bearbetningsmetodernas inverkan på de slutliga materialegenskaperna för att optimera prestandan för riktade tillämpningar. Dessutom har CNFers unika nätverksbildande egenskaper också utforskats i att skapa funktionella material med strukturell integritet från mycket små mängder CNFer i aerogelsystem baserade på makroskopiska cellulosarika fibrer och nanopartiklar av metallorganiska nätverk. Slutligen demonstrerades potentialen av de framställda cellulosabaserade och cellulosaförstärkta aerogelerna med utmärkt våtstyrka i tillämpningar där deras strukturella integritet, fysikaliska och mekaniska egenskaper kan användas på ett mycket fördelaktigt sätt, till exempel biomedicinska applikationer, gaslagring och -separering, flamskydd, och hygienprodukter. Mot bakgrund av dessa resultat är d, QC 20240522Embargo godkänt av skolchef Amelie Eriksson Karlström via e-post 2024-05-14

We report the first experimental evidence for rapid formation of hydrogen clathrates under mild pressure and temperature conditions within the cavities of a zirconium-metalloporphyrin framework, specifically PCN-222. PCN-222 has been selected for its 1D mesoporous channels, high water-stability, and proper hydrophilic behavior. Firstly, we optimize a microwave (MW)-assisted method for the synthesis of nanosized PCN-222 particles with precise structure control (exceptional homogeneity in morphology and crystalline phase purity), taking advantage of MW in terms of rapid/homogeneous heating, time and energy savings, as well as potential scalability of the synthetic method. Second, we explore the relevance of the large mesoporous 1D open channels within the PCN-222 to promote the nucleation and growth of confined hydrogen clathrates. Experimental results show that PCN-222 drives the nucleation process at a lower pressure than the bulk system (1.35 kbar vs 2 kbar), with fast kinetics (minutes), using pure water, and with a nearly complete water-to-hydrate conversion. Unfortunately, PCN-222 cannot withstand these high pressures, which lead to a significant alteration of the mesoporous structure while the microporous network remains mainly unchanged.

The increasing presence of microplastics (MPs) in aquatic environments has caused considerable concerns. Wastewater treatment plants (WWTPs) are recognized as major sources of MP discharge, underscoring the urgent need for improved techniques to efficiently remove MPs. Although polymeric membranes are effective for this purpose, fouling remains a primary challenge. Therefore, understanding the contribution of MPs to membrane fouling is crucial for developing efficient membrane-based MP removal techniques. Forward Osmosis (FO) emerges as a promising solution due to distinct advantages. Its energy efficiency aligns with minimal hydraulic pressure requirements. Furthermore, implementing FO in WWTPs, with seawater as the draw solution, could reduce the energy requirements for the draw solution recovery. This technology not only prevents entrance of MPs to the environment but also addresses other micro-contaminants affecting aquatic ecosystems. Successful implementation and utilization of FO systems relies on advanced FO membranes exhibiting high water permeability, low reverse salt flux (RSF), and robust resistance to fouling. Although FO experiences less severe membrane fouling compared to the other filtration techniques, attributed to its low or absent hydraulic pressure operation, fouling still contributes to the reduction of FO membranes’ performance. Additionally, MPs have been identified as emerging foulants in water treatment systems, diminishing the membranes’ efficiency and lifespan. Therefore, the presence of MPs in the effluent of WWTPs can exacerbate fouling and impair FO efficiency. Furthermore, simultaneous presence of MPs and other fouling agents can synergistically increase fouling, emphasizing the need to consider MP fouling when designing sustainable membranes. One of the main approaches to improve performance and antifouling behaviour of membranes is the integration of nanomaterials into the membrane structure. Metal-organic frameworks (MOFs) are nove

Porous materials, such as porous carbons (PCs), metal-organic frameworks (MOFs), and covalent organic frameworks (COFs), show considerable potential across various fields because of their rich microporous and mesoporous structures and large surface areas, yet they grapple with challenges like environmentally unfriendly fabrication methods and poor processability. In this thesis, we investigated environmentally friendly fabrication methods for porous materials, nanoengineering techniques for processing these materials, and their potential applications. Cladophora cellulose (CC), a naturally abundant biopolymer, was used to prepare PC via a one-step physical carbonization/activation method without using any corrosive activation agents. The obtained CC-derived PC (CPC) showed a high specific surface area (507.2 m2 g−1) and rich microporous structure. Additionally, we introduced a simple and environmentally friendly method for synthesizing imine-linked COFs at room temperature using water as the solvent. The method involves a key step in which aldehyde monomers are pre-activated by acetic acid, which promotes the aldehyde monomers to dissolve in water, enhancing their reactivity with amine monomers, and ensuring the formation of crystalline COFs. Consequently, we synthesized 16 distinct imine-linked COFs with high crystallinity and specific surface areas. Furthermore, this thesis focusses on improving the poor processability of these materials caused by the infusible and insoluble nature of their powders. The poor processability of these porous materials makes them difficult to process into desired structures and shapes. Here, we introduce two nanoengineering methods: i) Interweaving porous materials with CC nanofibers (CNFs) to form CNF-porous material aqueous solutions; and ii) Interfacial synthesis of porous materials on the surface of carboxylated CNFs to form CNF@porous materials with nanofiber structures in aqueous solutions. The obtained composite suspensions ca

Having an orbital-level understanding of the relationship between the electronic state of a central metal in metal-organic frameworks (MOFs) as solid-state electrolytes (SSEs) and Li+ ion conductivity is crucial yet challenging for lithium-metal batteries (LMBs). In this study, we report the synthesis of functionalized UiO-66 as a model system to investigate the relationship between the d-band energy of Zr 3d orbitals and Li+ ion conductivity. Specifically, the NO2 group in electron-withdrawing NO2-decorated UiO-66 (NO2-UiO-66) can capture electron from ZrO8 sites, resulting the increased energy in 3dz 2 and 3dxz/ yz orbitals of Zr atom. The high-energy 3dz 2 and 3dxz/ yz orbitals of Zr in NO2-UiO-66 hybridize with the 2pz and 2px/ y orbitals of O in ClO4-, leading to decreased antibonding orbital energy and resulting in a strong adsorption, ultimately immobilizing the anions and enhancing ion conductivities. Establishing the correlation between the d-orbital energy and Li+ ion conductivity may create a descriptor for designing efficient SSEs for LMBs.

Main group element-based materials are emerging catalysts for ammonia (NH3) production via a sustainable electrochemical nitrogen reduction reaction (N2RR) pathway under ambient conditions. However, their N2RR performances are less explored due to the limited active behavior and unclear mechanism. Here, an aluminum-based defective metal–organic framework (MOF), aluminum-fumarate (Al-Fum), is investigated. As a proof of concept, the pristine Al-Fum MOF is synthesized by the solvothermal reaction process, and the defect engineering method namely solvent-assisted linker exchange, is applied to create the defective Al sites. The defective Al sites play an important role in ensuring the N2RR activity for defective Al-Fum. It is found that only the defective Al-Fum enables stable and effective electrochemical N2RR, in terms of the highest production rate of 53.9 µg(NH3) h−1mgcat−1 (in 0.4 m K2SO4) and the Faradaic efficiency of 73.8% (in 0.1 m K2SO4) at −0.15 V vs reversible hydrogen electrode) under ambient conditions. Density functional theory calculations confirm that the N2 activation can be achieved on the defective Al sites. Such sites also allow the subsequent protonation process via the alternating associative mechanism. This defect characteristic gives the main group Al-based MOFs the ability to serve as promising electrocatalysts for N2RR and other attractive applications. © 2023 Wiley-VCH GmbH.

Polymer composite electrolytes (PCEs), i.e., materials combining the disciplines of polymer chemistry, inorganic chemistry, and electrochemistry, have received tremendous attention within academia and industry for lithium-based battery applications. While PCEs often comprise 3D micro- or nanoparticles, this review thoroughly summarizes the prospects of 2D layered inorganic, organic, and hybrid nanomaterials as active (ion conductive) or passive (nonion conductive) fillers in PCEs. The synthetic inorganic nanofillers covered here include graphene oxide, boron nitride, transition metal chalcogenides, phosphorene, and MXenes. Furthermore, the use of naturally occurring 2D layered clay minerals, such as layered double hydroxides and silicates, in PCEs is also thoroughly detailed considering their impact on battery cell performance. Despite the dominance of 2D layered inorganic materials, their organic and hybrid counterparts, such as 2D covalent organic frameworks and 2D metal-organic frameworks are also identified as tuneable nanofillers for use in PCE. Hence, this review gives an overview of the plethora of options available for the selective development of both the 2D layered nanofillers and resulting PCEs, which can revolutionize the field of polymer-based solid-state electrolytes and their implementation in lithium and post-lithium batteries.

Polymer composite electrolytes (PCEs), i.e., materials combining the disciplines of polymer chemistry, inorganic chemistry, and electrochemistry, have received tremendous attention within academia and industry for lithium-based battery applications. While PCEs often comprise 3D micro- or nanoparticles, this review thoroughly summarizes the prospects of 2D layered inorganic, organic, and hybrid nanomaterials as active (ion conductive) or passive (nonion conductive) fillers in PCEs. The synthetic inorganic nanofillers covered here include graphene oxide, boron nitride, transition metal chalcogenides, phosphorene, and MXenes. Furthermore, the use of naturally occurring 2D layered clay minerals, such as layered double hydroxides and silicates, in PCEs is also thoroughly detailed considering their impact on battery cell performance. Despite the dominance of 2D layered inorganic materials, their organic and hybrid counterparts, such as 2D covalent organic frameworks and 2D metal-organic frameworks are also identified as tuneable nanofillers for use in PCE. Hence, this review gives an overview of the plethora of options available for the selective development of both the 2D layered nanofillers and resulting PCEs, which can revolutionize the field of polymer-based solid-state electrolytes and their implementation in lithium and post-lithium batteries.

Two new alkaline earth metal–organic frameworks (AE-MOFs) containing Sr(II) (UPJS-15) or Ba(II) (UPJS-16) cations and extended tetrahedral linker (MTA) were synthesized and characterized in detail (UPJS stands for University of Pavol Jozef Safarik). Single-crystal X-ray analysis (SC-XRD) revealed that the materials are isostructural and, in their frameworks, one-dimensional channels are present with the size of ~11 × 10 2. The activation process of the compounds was studied by the combination of in situ heating infrared spectroscopy (IR), thermal analysis (TA) and in situ high-energy powder X-ray diffraction (HE-PXRD), which confirmed the stability of compounds after desolvation. The prepared compounds were investigated as adsorbents of different gases (Ar, N2, CO2, and H2). Nitrogen and argon adsorption measurements showed that UPJS-15 has SBET area of 1321 m2 g1 (Ar) / 1250 m2 g1 (N2), and UPJS-16 does not adsorb mentioned gases. From the environmental application, the materials were studied as CO2 adsorbents, and both compounds adsorb CO2 with a maximum capacity of 22.4 wt.% @ 0 °C; 14.7 wt.% @ 20 °C and 101 kPa for UPJS-15 and 11.5 wt.% @ 0°C; 8.4 wt.% @ 20 °C and 101 kPa for UPJS-16. According to IAST calculations, UPJS-16 shows high selectivity (50 for CO2/N2 10:90 mixture and 455 for CO2/N2 50:50 mixture) and can be applied as CO2 adsorbent from the atmosphere even at low pressures. The increased affinity of materials for CO2 was also studied by DFT modelling, which revealed that the primary adsorption sites are coordinatively unsaturated sites on metal ions, azo bonds, and phenyl rings within the MTA linker. Regarding energy storage, the materials were studied as hydrogen adsorbents, but the materials showed low H2 adsorption properties: 0.19 wt.% for UPJS-15 and 0.04 wt.% for UPJS-16 @ 196 °C and 101 kPa. The enhanced CO2/H2 selectivity could be used to scavenge carbon dioxide from hydrogen in WGS and DSR reactions. The second method of applying samples in

We report the first experimental evidence for rapid formation of hydrogen clathrates under mild pressure and temperature conditions within the cavities of a zirconium-metalloporphyrin framework, specifically PCN-222. PCN-222 has been selected for its 1D mesoporous channels, high water-stability, and proper hydrophilic behavior. Firstly, we optimize a microwave (MW)-assisted method for the synthesis of nanosized PCN-222 particles with precise structure control (exceptional homogeneity in morphology and crystalline phase purity), taking advantage of MW in terms of rapid/homogeneous heating, time and energy savings, as well as potential scalability of the synthetic method. Second, we explore the relevance of the large mesoporous 1D open channels within the PCN-222 to promote the nucleation and growth of confined hydrogen clathrates. Experimental results show that PCN-222 drives the nucleation process at a lower pressure than the bulk system (1.35 kbar vs 2 kbar), with fast kinetics (minutes), using pure water, and with a nearly complete water-to-hydrate conversion. Unfortunately, PCN-222 cannot withstand these high pressures, which lead to a significant alteration of the mesoporous structure while the microporous network remains mainly unchanged.

Crystalline Zr-fum-MOF (MOF-801) thin films of high quality are prepared on glass and silicon substrates by direct growth under solvothermal conditions. The synthesis is described in detail and the influence of different synthesis parameters such as temperature, precursor concentration, and the substrate type on the quality of the coatings is illustrated. Zr-fum-MOF thin films are characterized in terms of crystallinity, porosity, and homogeneity. Dense films of optical quality are obtained. The sorption behavior of the thin films is studied with various adsorptives. It can be easily monitored by measuring the transmission of the films in gas flows of different compositions. This simple transmission measurement at only one wavelength allows a very fast evaluation of the adsorption properties of thin films as compared to traditional sorption methods. The sorption behavior of the thin films is compared with the sorption properties of Zr-fum-MOF powder samples.

Catalyst fragmentation behavior and polymer particle morphology evolution are two critical factors for obtaining high-quality polyethylene (PE). However, for metal-organic frameworks (MOFs), emerging catalysts for ethylene polymerization, systematic studies related to their fragmentation behavior and PE morphology evolution from early stages are still missing. Here, we provide a strategy by using MOF thin films as 2D model catalysts to elucidate PE growth and fragmentation behavior of MOFs in ethylene polymerization. The morphological evolution and particle expansion processes of the formed PE are observed as a function of polymerization time, which is linked to the morphology of MOFs and the crystallinity of produced PE. Moreover, the fragmentation process is visualized, revealing a combination of layer-by-layer and bisectioning fragmentation modes at very early stages and a dominant bisectioning fragmentation later. The desirable fragmentation behavior of MIL-101 (Cr) and PE growth and morphology indicate the potential of MOFs in ethylene polymerization.

Spectroscopy on metal–organic framework (MOF) films and the molecular phenomena associated to them is mostly limited to grazing incidence methods. To allow for transmission-based characterization and highlight the applicability of MOFs on transparent substrates, UiO-67, UU-1, and ZIF-8 MOFs are synthesized on CaF2 windows. It is revealed that the growth of the UiO-67 MOF follows a Volmer–Weber mechanism using scanning electron microscopy (SEM). This growth is assisted by growing seeds in solution, which anchor on the film and become part of the intergrown film itself. UU-1, a copper-based MOF, is formed after spin coating the Cu-BTC precursors, showing its characteristic fiber-like morphology and resulting inter-fiber macroporosity. ZIF-8 is formed using a “flash”-synthesis, and it is shown that this approach resembles a Volmer–Weber growth mode as well. Last, CO probe molecule adsorption FT-IR spectroscopy is utilized to study the effect of methanol exposure. UiO-67 becomes inaccessible toward CO, due to the formation of methoxy species, whereas UU-1 undergoes a topotactic transformation to HKUST-1. ZIF-8 is the most stable as methanol only removes impurities from the framework. This approach opens the venue for other film materials to be studied in situ synthesis, sorption, or catalysis using transmission-based spectroscopy.

Unveiling intracellular drug metabolism is crucial for improving drug development, which requires real-time detection with molecular selectivity in the intracellular environment. Surface-enhanced Raman scattering (SERS) with metal nanoparticles enables the detection of molecules in living cells, but after entering the cells, most nanoparticles are captured into vesicles, limiting the SERS detection inside these compartments. Moreover, the identification of the target signal in the complex intracellular environment is challenging due to Raman fingerprints from endogenous material interfering with the drug signal. To overcome these issues, here the coating of a silver nanowire with zeolitic imidazolate framework-8 (ZIF-8) as a novel endoscopic probe with molecular selectivity to investigate the location and metabolism in cells of a common anticancer drug, irinotecan, is reported. Irinotecan in cells is metabolized by carboxylesterase to form SN-38, which inhibits topoisomerase I and DNA synthesis. Thanks to the molecular selectivity of ZIF-8, the endoscopic probe selectively adsorbs and detects SERS signal of SN-38 over irinotecan. This selectivity enables monitoring of the conversion of irinotecan into SN-38 and following its intracellular location over time. This work clearly shows the potential of metal-organic framework-coated nanowire endoscopy to specifically track drug molecules and explore their metabolism in cells.

Surface microbial colonization and its potential biofilm formation are currently a major unsolved problem, causing almost 75% of human infectious diseases. Pathogenic biofilms are capable of surviving high antibiotic doses, resulting in inefficient treatments and, subsequently, raised infection prevalence rates. Antibacterial coatings have become a promising strategy against the biofilm formation in biomedical devices due to their biocidal activity without compromising the bulk material. Here, we propose for the first time a silver-based metal–organic framework (MOF; here denoted AgBDC) showing original antifouling properties able to suppress not only the initial bacterial adhesion, but also the potential surface contamination. Firstly, the AgBDC stability (colloidal, structural and chemical) was confirmed under bacteria culture conditions by using agar diffusion and colony counting assays, evidencing its biocide effect against the challenging E. coli, one of the main representative indicators of Gram-negative resistance bacteria. Then, this material was shaped as homogeneous spin-coated AgBDC thin film, investigating its antifouling and biocide features using a combination of complementary procedures such as colony counting, optical density or confocal scanning microscopy, which allowed to visualize for the first time the biofilm impact generated by MOFs via a specific fluorochrome, calcofluor., Comunidad de Madrid, European Regional Development Fund, European Union’s Horizon 2020, European Research Council (Advanced Grant VERDI; ERC-2015-AdG Proposal No 694160), Depto. de Química en Ciencias Farmacéuticas, Fac. de Farmacia, TRUE, pub

In this work, thin composite films of zeolitic imidazolate frameworks (ZIFs) and colloidal two-dimensional (2D) core-crown CdSe/CdS nanoplatelet (NPL) emitters with minimal scattering are formed by a cycled growth method and yield highly transparent coatings with strong and narrow photoluminescence of the NPLs at 546 nm (FWHM: 25 nm) in a solid-state composite structure. The porous ZIF matrix acts as functional encapsulation for the emitters and enables the adsorption of the guest molecules water and ethanol. The adsorption and desorption of the guest molecules is then characterized by a reversable photoluminescence change of the embedded NPLs. The transmittance of the composite films exceeds the values of uncoated glass at visible wavelengths where the NPL emitters show no absorption (>540 nm) and renders them anti-reflective coatings. At NPL absorption wavelengths (440–540 nm), the transmittance of the thin composite film-coated glass lies close to the transmittance of uncoated glass. The fast formation of innovative, smooth NPL/ZIF composite films without pre-polymerizing the colloidal 2D nanostructures first provides a powerful tool toward application-oriented photoluminescence-based gas sensing.

Metal–organic frameworks (MOFs) are microporous adsorbents for high-throughput gas separation. Such materials exhibit distinct adsorption characteristics owing to the flexibility of the crystal framework in a nanoparticle, which can be different from its bulk crystal. However, for practical applications, such particles need to be compacted into macroscopic pellets, creating mass-transport limitations. In this work, this problem is addressed by forming materials with structural hierarchy, using a supraparticle-based approach. Spherical supraparticles composed of nanosized MOF particles are fabricated by emulsion templating and they are used as the structural component forming a macroscopic material. Zeolitic imidazolate framework-8 (ZIF-8) particles are used as a model system and the gas-adsorption kinetics of the hierarchical material are compared with conventional pellets without structural hierarchy. It is demonstrated that a pellet packed with supraparticles exhibits a 30 times faster adsorption rate compared to an unstructured ZIF-8 powder pellet. These results underline the importance of controlling structural hierarchy to maximize the performance of existing materials. In the hierarchical MOFs, large macropores between the supraparticles, smaller macropores between individual ZIF-8 primary particles, and micropores inherent to the ZIF-8 framework collude to combine large surface area, defined adsorption sites, and efficient mass transport to enhance performance.

Flexible metal–organic frameworks (MOFs) exhibit an adsorption-induced structural transition known as “gate opening” or “breathing, ” resulting in an S-shaped adsorption isotherm. This unique feature of flexible MOFs offers significant advantages, such as a large working capacity, high selectivity, and intrinsic thermal management capability, positioning them as crucial candidates for revolutionizing adsorption separation processes. Therefore, the interest in the industrial applications of flexible MOFs is increasing, and the adsorption engineering for flexible MOFs is becoming important. However, despite the establishment of the theoretical background for adsorption-induced structural transitions, no theoretical equation is available to describe S-shaped adsorption isotherms of flexible MOFs. Researchers rely on various empirical equations for process simulations that can lead to unreliable outcomes or may overlook insights into improving material performance owing to parameters without physical meaning. In this study, we derive a theoretical equation based on statistical mechanics that could be a standard for the structural transition type adsorption isotherms, as the Langmuir equation represents type I isotherms. The versatility of the derived equation is shown through four examples of flexible MOFs that exhibit gate opening and breathing. The consistency of the formula with existing theories, including the osmotic free energy analysis and intrinsic thermal management capabilities, is also discussed. The developed theoretical equation may lead to more reliable and insightful outcomes in adsorption separation processes, further advancing the direction of industrial applications of flexible MOFs.

Developing artificial porous systems with high molecular recognition performance is critical but very challenging to achieve selective uptake of a particular component from a mixture of many similar species, regardless of the size and affinity of these competing species. A porous platform that integrates multiple recognition mechanisms working cooperatively for highly efficient guest identification is desired. Here, we designed a flexible porous coordination polymer (PCP) and realised a corrugated channel system that cooperatively responds to only target gas molecules by taking advantage of its stereochemical shape, location of binding sites, and structural softness. The binding sites and structural deformation act synergistically, exhibiting exclusive discrimination gating (EDG) effect for selective gate-opening adsorption of CO₂ over nine similar gas molecules, including N₂, CH₄, CO, O₂, H₂, Ar, C₂H₆, and even higher-affinity gases such as C₂H₂ and C₂H4. Combining in-situ crystallographic experiments with theoretical studies, it is clear that this unparalleled ability to decipher the CO₂ molecule is achieved through the coordination of framework dynamics, guest diffusion, and interaction energetics. Furthermore, the gas co-adsorption and breakthrough separation performance render the obtained PCP an efficient adsorbent for CO₂ capture from various gas mixtures.

A one-stone, two-bird method to integrate the soft porosity and electrical properties of distinct metal–organic frameworks (MOFs) into a single material involves the design of conductive-on-insulating MOF (cMOF-on-iMOF) heterostructures that allow for direct electrical control. Herein, we report the synthesis of cMOF-on-iMOF heterostructures using a seeded layer-by-layer method, in which the sorptive iMOF core is combined with chemiresistive cMOF shells. The resulting cMOF-on-iMOF heterostructures exhibit enhanced selective sorption of CO₂ compared to the pristine iMOF (298 K, 1 bar, S[CO₂/H₂] from 15.4 of ZIF-7 to 43.2–152.8). This enhancement is attributed to the porous interface formed by the hybridization of both frameworks at the molecular level. Furthermore, owing to the flexible structure of the iMOF core, the cMOF-on-iMOF heterostructures with semiconductive soft porous interfaces demonstrated high flexibility in sensing and electrical “shape memory” toward acetone and CO₂. This behavior was observed through the guest-induced structural changes of the iMOF core, as revealed by the operando synchrotron grazing incidence wide-angle X-ray scattering measurements.