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A series of zirconium-based MOFs with acclaimed stability was prepared and their ability to adsorb polyfluorinated pollutants was compared. A novel fluorinated UiO-67 analogue, UiO-67-F2, was synthesised alongside three previously reported materials: UiO-67-NH2, UiO-68-(CF3)2 and UiO-67. The structures were established and confirmed by powder X-Ray diffraction. UiO-67-NH2, UiO-68(CF3)2 and UiO-67-F2 were examined as sorbents for the perfluorinated gas, sulphur hexafluoride (SF₆) from the gaseous phase. The SF₆ uptake of UiO-67-NH2 and UiO-67-F2 at 100 kPa, 293 K, was high (5.54 and 5.24 mmol g ^-1 respectively). UiO-67-F2 exhibited a remarkable perfluorinated octanoic acid (PFOA) uptake of 928 mg_PFOA g ^-1_MOF in an aqueous solution, which far exceeded that of unmodified UiO-67 (872 mg_PFOA g ^-1_MOF at 1 000 mg_PFOA L ^-1_Water PFOA). This study has identified strengths and potential applications of the novel UiO-67-F2 and the impact of fluorine functionalization. The study also offers insight into the structure-property relations of UiO-based MOFs for their use as low-pressure SF6 storage materials and PFAS sorbents intended for water purification under ambient conditions.

Molecular catalysts for water oxidation and other electrochemical transformations have been a focus of significant research over recent decades. Among these, α-[Fe(mcp)L2] complexes stand out as one of the most active non-heme iron-based molecular catalyst for water oxidation. This study investigates how the Fe(II)/Fe(III) redox potential of these catalysts varies with the identity of their labile ligands (L). Using cyclic voltammetry and complementary spectroscopic techniques (UV/Vis, 1H-NMR), we examined how ligands bind to the metal centre. Systematic variation of the labile ligand (L) demonstrated that the catalyst's redox potential in acetonitrile solution strongly depends on ligand identity. By introducing stoichiometric amounts of different anions to the electrolyte, the redox potential was tuned across a 1.5 V potential window.In aqueous solutions, the redox potential depended on both pH and electrolyte anion identity. These dependencies were successfully fitted to a thermodynamic model that was obtained by extending the typical proton-coupled electron transfer square scheme into a cube scheme that incorporates anion binding. The equation derived from this model provides valuable insights into the ligand-binding dynamics at the iron centre under diverse conditions.

Flexible supercapacitors hold promise for applications in wearable electronic devices. However, the challenges of achieving flexibility, miniaturization, and high volumetric capacitance persist. In this work, precise laser etching of cellulose composites, prepared via in-situ growth of conductive metal–organic frameworks (c-MOFs) on cellulose nanofibers (CNF), was employed to fabricate flexible, binder-free, and integrated microsupercapacitors (MSCs). The interfacial synthesis of Ni₃(HITP)₂ (a type of c-MOF) on the surface of CNF yields a continuous and uniform conductive shell, enabling efficient electron transfer along the CNF@c-MOF nanofibers. The interwoven structure of the nanofibers creates a hierarchical porous network with enhanced surface area featuring interconnected porous channels, enabling rapid ion transport. The laser etching technique facilitates one-step production of integrated MSCs with a precisely interdigitated configurations and micron-scale accuracy. The fabricated MSCs demonstrate excellent mechanical stability, with a tensile strength of up to 81.9 MPa, and remarkable flexibility, maintaining consistent electrochemical performance under bending stress. The flexible device, with a thickness of only 45 µm, achieves a high volumetric specific capacitance of 36.7 F cm⁻³ at a current density of 0.17 mA cm⁻² and a specific energy density of 2,497.5 µWh cm⁻³ at a power density of 53.3 mW cm⁻³. This study provides a new strategy for designing flexible, binder-free, integrated MSCs with high capacitances and long cyclic stability, demonstrating significant potential for applications in wearable electronics.

Selective Laser Sintering (SLS) is an emerging additive manufacturing technology with potential for the production of personalized pharmaceuticals. In this study, we investigated a novel simplified formulation approach in SLS-based manufacturing of individually dosed, multi-layered tablets with distinct layers of pure active pharmaceutical ingredient (API) and excipient. Indomethacin (IND) was chosen as the model API, and polyvinyl alcohol (PVA) served as the excipient. Unlike conventional methods requiring powder blending, this approach utilizes separate powder tanks for IND and PVA, enabling direct printing of alternating layers in a single-step procedure. We successfully fabricated tablets with controlled IND doses by varying the number of IND layers, maintaining consistent printing parameters across different compositions and confirming the API’s chemical stability in the product. Since SLS is conventionally used for thermoplastic substances, the successful sintering of pure IND layers was a key achievement in the study, as this crystalline API is typically not printable separately. Energy dispersive X-ray spectroscopy (EDS) demonstrated the successful formation of distinct API and excipient layers. Differential scanning calorimetry (DSC) characterization revealed that the sintering process partially amorphized IND, which may enhance dissolution and bioavailability. Dissolution testing indicated that the printed tablets exhibited improved dissolution rates compared to raw IND powder. The study successfully demonstrated the possibility of SLS-based production for personalized dosing by omitting powder blending steps. The ability to create individualized dosages with minimal excipients and simplified processing represents a step toward further investigation of SLS for clinical settings, including hospital and pharmacy-based drug production.

Wearable electronics are some of the most promising technologies with the potential to transform many aspects of human life such as smart healthcare and intelligent communication. The design of self-powered fabrics with the ability to efficiently harvest energy from the ambient environment would not only be beneficial for their integration with textiles, but would also reduce the environmental impact of wearable technologies by eliminating their need for disposable batteries. Herein, inspired by classical Archimedean spirals, we report a metastructured fiber fabricated by scrolling followed by cold drawing of a bilayer thin film of an MXene and a solid polymer electrolyte. The obtained composite fibers with a typical spiral metastructure (SMFs) exhibit high efficiency for dispersing external stress, resulting in simultaneously high specific mechanical strength and toughness. Furthermore, the alternating layers of the MXene and polymer electrolyte form a unique, tandem ionic–electronic coupling device, enabling SMFs to generate electricity from diverse environmental parameters, such as mechanical vibrations, moisture gradients, and temperature differences. This work presents a design rule for assembling planar architectures into robust fibrous metastructures, and introduces the concept of ionic–electronic coupling fibers for efficient multimodal energy harvesting, which have great potential in the field of self-powered wearable electronics.

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.

Covalent organic frameworks (COFs) are usually synthesized under solvothermal conditions that require the use of toxic organic solvents, high reaction temperatures, and complicated procedures. Additionally, their insolubility and infusibility present substantial challenges in the processing of COFs. Herein, we report a facile, green approach for the synthesis of imine-linked COFs in an aqueous solution at room temperature. The key behind the synthesis is the regulation of the reaction rate. The preactivation of aldehyde monomers using acetic acid significantly enhances their reactivity in aqueous solutions. Meanwhile, the still somewhat lower imine formation rate and higher imine breaking rates in aqueous solution, in contrast to conventional solvothermal synthesis, allow for the modulation of the reaction equilibrium and the crystallization of the products. As a result, highly crystalline COFs with large surface areas can be formed in relatively high yields in a few minutes. In total, 16 COFs are successfully synthesized from monomers with different molecular sizes, geometries, pendant groups, and core structures, demonstrating the versatility of this approach. Notably, this method works well on the gram scale synthesis of COFs. Furthermore, the aqueous synthesis facilitates the interfacial growth of COF nanolayers on the surface of cellulose nanofibers (CNFs). The resulting CNF@COF hybrid nanofibers can be easily processed into freestanding nanopapers, demonstrating high efficiency in removing trace amounts of antibiotics from wastewater. This study provides a route to the green synthesis and processing of various COFs, paving the way for practical applications in diverse fields.

Lignin is an aromatic biomacromolecule with many promising properties that can be beneficial to polymer blends. The main objective of this work was to investigate the processability, compatibility, and recyclability of lignin blends with poly(lactic acid). Two different commercial kraft lignins and a phenolated organosolv lignin were blended with poly(lactic acid) at various weight percentages, targeting high lignin content (30, 50, and 70 wt %). Obtained blends were used in additive manufacturing via fused deposition modeling. All obtained materials were thoroughly characterized by tensile tests, thermogravimetric analysis, differential scanning calorimetry, and 31P NMR. The recyclability of the polymer blend materials was evaluated by re-extruding them up to four times, and their printability was also assessed. The results showed that the material retained its mechanical properties relatively well for up to three cycles after which its tensile strength decreased by 30%. Phenolated organosolv lignin exhibited better printability across a broader range of lignin content compared to kraft lignin analogs while maintaining similar thermal and mechanical properties.

Poorly soluble drugs represent a substantial portion of emerging drug candidates, posing significant challenges for pharmaceutical formulators. One promising method to enhance the drug’s dissolution rate and, consequently, bioavailability involves transforming them into an amorphous state within mesoporous materials. These materials can then be seamlessly integrated into personalized drug formulations using Additive Manufacturing (AM) techniques, most commonly via Fused Deposition Modeling. Another innovative approach within the realm of AM for mesoporous material-based formulations is semi-solid extrusion (SSE). This study showcases the feasibility of a straightforward yet groundbreaking hybrid 3D printing system employing SSE to incorporate drug-loaded mesoporous magnesium carbonate (MMC) into two different drug formulations, each designed for distinct administration routes. MMC was loaded with the poorly water-soluble drug ibuprofen via a solvent evaporation method and mixed with PEG 400 as a binder and lubricant, facilitating subsequent SSE. The formulation is non-aqueous, unlike most pastes which are used for SSE, and thus is beneficial for the incorporation of poorly water-soluble drugs. The 3D printing process yielded tablets for oral administration and suppositories for rectal administration, which were then analyzed for their dissolution behavior in biorelevant media. These investigations revealed enhancements in the dissolution kinetics of the amorphous drug-loaded MMC formulations. Furthermore, an impressive drug loading of 15.3 % w/w of the total formulation was achieved, marking the highest reported loading for SSE formulations incorporating mesoporous materials to stabilize drugs in their amorphous state by a wide margin. This simple formulation containing PEG 400 also showed advantages over other aqueous formulations for SSE in that the formulations did not exhibit weight loss or changes in size or form during the curing process post-printing. These results underscore the substantial potential of this innovative hybrid 3D printing system for the development of drug dosage forms, particularly for improving the release profile of poorly water-soluble drugs.