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In recent years, European Union member states have hastened energy policy deliberations to address supply and sustainability concerns, placing a significant emphasis on nuclear energy as a means to achieve decarbonization goals. However, despite its significant role in power generation, nuclear energy faces significant challenges linked to fuel reprocessing and waste disposal, that hinder its broader expansion. In this context, the separation of technetium represents a concerning issue. Indeed, technetium's catalytic activity can impede the extraction of uranium, neptunium, and plutonium, affecting waste reprocessing efficiency. Additionally, the stable form of technetium in aerobic conditions, pertechnetate (TcO4−), poses risks of groundwater contamination due to its mobility and solubility. Hence, sensing and separation of TcO4− is imperative for both nuclear fuel processing and minimising radioactive contamination in the environment. However, the binding of TcO4− and its separation from contaminated solutions present challenges due to the acidic (or basic) waste components and the high ionic strength in real matrices. Supramolecular chemists have addressed these issues by designing receptors inspired by molecular recognition principles. This article explores recent advancements and future directions in TcO4− sensing and separation (using extraction and sorption) with a focus on molecular hosts. Metal‐organic receptors will also be discussed. [ABSTRACT FROM AUTHOR]

In recent years, European Union member states have hastened energy policy deliberations to address supply and sustainability concerns, placing a significant emphasis on nuclear energy as a means to achieve decarbonization goals. However, despite its significant role in power generation, nuclear energy faces significant challenges linked to fuel reprocessing and waste disposal, that hinder its broader expansion. In this context, the separation of technetium represents a concerning issue. Indeed, technetium's catalytic activity can impede the extraction of uranium, neptunium, and plutonium, affecting waste reprocessing efficiency. Additionally, the stable form of technetium in aerobic conditions, pertechnetate (TcO4−), poses risks of groundwater contamination due to its mobility and solubility. Hence, sensing and separation of TcO4− is imperative for both nuclear fuel processing and minimising radioactive contamination in the environment. However, the binding of TcO4− and its separation from contaminated solutions present challenges due to the acidic (or basic) waste components and the high ionic strength in real matrices. Supramolecular chemists have addressed these issues by designing receptors inspired by molecular recognition principles. This article explores recent advancements and future directions in TcO4− sensing and separation (using extraction and sorption) with a focus on molecular hosts. Metal‐organic receptors will also be discussed. [ABSTRACT FROM AUTHOR]

Organic cages are three-dimensional polycyclic compounds of great interest in the scientific community due to their unique features, which generally include simple synthesis based on the dynamic covalent chemistry strategies, structural tunability and high selectivity. In this feature article, we present the advances over the last ten years in the application of organic cages as chemosensors or components in chemosensing devices for the determination of analytes (pollutants, analytes of biological interest) in complex aqueous media including wine, fruit juice, urine. Details on the recent applications of organic cages as selective (back-)extractants or masking agents for potential applications in relevant separation processes, such as the plutonium and uranium recovery by extraction, are also provided. Over the last ten years, organic cages with permanent porosity in the liquid and solid states have been highly appreciated as porous materials able to discriminate molecules of different sizes. These features, combined with good solvent processability and film-forming tendency, have proved useful in the fabrication of membranes for gas separation, solvent nanofiltration and water remediation processes. An overview of the recent applications of organic cages in membrane separation technologies is given. [ABSTRACT FROM AUTHOR]

Correction for 'Recent applications of organic cages in sensing and separation processes in solution' by Sonia La Cognata et al., Chem. Commun., 2023, 59, 13668–13678, https://doi.org/10.1039/D3CC04522F. [ABSTRACT FROM AUTHOR]

Two novel imide/imine‐based organic cages have been prepared and studied as materials for the selective separation of CO2 from N2 and CH4 under vacuum swing adsorption conditions. Gas adsorption on the new compounds showed selectivity for CO2 over N2 and CH4. The cages were also tested as fillers in mixed‐matrix membranes for gas separation. Dense and robust membranes were obtained by loading the cages in either Matrimid® or PEEK‐WC polymers. Improved gas‐transport properties and selectivity for CO2 were achieved compared to the neat polymer membranes. [ABSTRACT FROM AUTHOR]

Cover Feature: Gas Permeation through Mechanically Resistant Self-Standing Membranes of a Neat Amorphous Organic Cage (Chem. Eur. J. 56/2023) Keywords: gas transport; membranes; molecular materials; organic cages; thin films EN gas transport membranes molecular materials organic cages thin films 1 1 1 10/12/23 20231009 NES 231009 B Gas separation b : A novel organic cage with excellent film-forming tendencies was processed into transparent, mechanically robust, self-standing membranes of controllable thickness. Gas transport, membranes, molecular materials, organic cages, thin films. [Extracted from the article]

In recent years, European Union member states have hastened energy policy deliberations to address supply and sustainability concerns, placing a significant emphasis on nuclear energy as a means to achieve decarbonization goals. However, despite its significant role in power generation, nuclear energy faces significant challenges linked to fuel reprocessing and waste disposal, that hinder its broader expansion. In this context, the separation of technetium represents a concerning issue. Indeed, technetium's catalytic activity can impede the extraction of uranium, neptunium, and plutonium, affecting waste reprocessing efficiency. Additionally, the stable form of technetium in aerobic conditions, pertechnetate (TcO 4 - ), poses risks of groundwater contamination due to its mobility and solubility. Hence, sensing and separation of TcO 4 - is imperative for both nuclear fuel processing and minimising radioactive contamination in the environment. However, the binding of TcO 4 - and its separation from contaminated solutions present challenges due to the acidic (or basic) waste components and the high ionic strength in real matrices. Supramolecular chemists have addressed these issues by designing receptors inspired by molecular recognition principles. This article explores recent advancements and future directions in TcO 4 - sensing and separation (using extraction and sorption) with a focus on molecular hosts. Metal-organic receptors will also be discussed., (© 2024 Wiley-VCH GmbH.)

The synthesis and characterization of a novel film-forming organic cage and of its smaller analogue are here described. While the small cage produced single crystals suitable for X-ray diffraction studies, the large one was isolated as a dense film. Due to its remarkable film-forming properties, this latter cage could be solution processed into transparent thin-layer films and mechanically stable dense self-standing membranes of controllable thickness. Thanks to these peculiar features, the membranes were also successfully tested for gas permeation, reporting a behavior similar to that found with stiff glassy polymers such as polymers of intrinsic microporosity or polyimides. Given the growing interest in the development of molecular-based membranes, for example for separation technologies and functional coatings, the properties of this organic cage were investigated by thorough analysis of their structural, thermal, mechanical and gas transport properties, and by detailed atomistic simulations., (© 2023 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)

Two novel imide/imine-based organic cages have been prepared and studied as materials for the selective separation of CO 2 from N 2 and CH 4 under vacuum swing adsorption conditions. Gas adsorption on the new compounds showed selectivity for CO 2 over N 2 and CH 4 . The cages were also tested as fillers in mixed-matrix membranes for gas separation. Dense and robust membranes were obtained by loading the cages in either Matrimid® or PEEK-WC polymers. Improved gas-transport properties and selectivity for CO 2 were achieved compared to the neat polymer membranes., (© 2022 The Authors. Chemistry - A European Journal published by Wiley-VCH GmbH.)