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Developing technologies to capture, purify, and reuse potent greenhouse gases such as sulfur hexafluoride (SF₆) is crucial because of their high global warming potential. Porous solid matrices are promising candidates for this purpose, due to their high surface areas and pore volumes. Herein, two coconut shell–derived activated carbons (AC) (CS-CO₂ and CS-ZnCl₂), obtained through physical and chemical activation, are evaluated and compared with two commercial adsorbents: an AC monolith (ACM) and a metal-organic framework. The adsorption capacities for SF₆ and nitrogen (N₂) are measured gravimetrically at three temperatures: 283.15, 303.15, and 323.15 K. The experimental data are fitted using the Toth model, and the impact of temperature and pressure on the adsorption performance is analyzed. The order of SF₆ adsorption capacity is: ACM > CS-ZnCl₂ > Fe-BTC > CS-CO₂, reflecting dependence on surface area. Selectivity for SF₆/N₂ separation is evaluated using Ideal Adsorbed Solution Theory, with ACM exhibiting the highest adsorption capacity due to its selective separation properties. These findings contribute to the understanding and selection of efficient adsorbent materials for SF₆ separation and recovery, providing valuable insights for their future implementation in industrial gas treatment and environmental management applications.

Cyclodextrin is a typical macrocyclic molecule that can recognize and bind numerous guest molecules with specific structure and functional groups. The cyclodextrin-based supramolecular nanostructures, characterized by well-defined, ordered, compact, and regular molecular arrangements, are widely utilized in drug delivery, sensing, and light-harvesting systems. Their unique physicochemical properties have further expanded the scope of research in both biophysics and chemistry. In this review, we provide an overview of the concepts and applications of cyclodextrin-based supramolecular nanostructures, with a focus on their relevance to biochemistry and chemistry.

Developing systems that facilitate the conversion of solar energy into fuel by reducing carbon dioxide and producing hydrogen could bridge the gap between production and consumption. In this work, a new method to study the reaction intermediates of carbon dioxide reduction reaction (CO₂RR) and hydrogen elimination reaction (HER) catalyzed by Cobalt(III) catalysts with high photocatalytic activity in a water/acetonitrile solvent system is proposed. The optimization of the cobalt catalysts ([Co(acac)(bpy)(N₃)₂].H₂O 1, [Co(acac)(en)(N₃)₂] 2 and [Co(acac)(2-pic)(N₃)₂] 3) for photocatalytic activities in visible light irradiation (>420 nm) is performed by varying solvents systems (v/v) (CH₃COCH₃/H₂O, CH₃CN/H₂O, DMF/H₂O, EtOH/H₂O and H₂O), sacrificial electron donors (1-benzyl-1,4-dihydronicotinamide (BNAH), diethanolamine (DEOA), triethylamine (TEA), and triethanolamine (TEOA), photosensitizers (Eosin Y, Erythrosin B, Fluorescein (Fl), Rose Bengal, Rhodamine-B, and Ru(bpy)₃ (Ru)), pH (7–12.5) and different catalyst concentrations (0–2 mM). The arrangement around the Cobalt(III) ion is an octahedral coordination geometry. A combination of experimental characterization and density functional theory (DFT) is used to identify the mechanism of the photocatalytic CO₂ reduction reaction. DFT calculations and experimental results for the photocatalytic activity of the catalysts 1–3 reveal the involvement of multi-electron metal-ligand exchange coupling in promoting CO₂RR and HER, and provide a starting point for the integration of these strategies into catalyst design.

Cyanines comprise a diverse group of small-molecule polymethine dyes combining tunable optical properties with high molar absorptivity and fluorescence emission quantum yield, enabling various applications in bioimaging, diagnostics, molecular electronics, photonics, and nonlinear optics. These applications can be facilitated by adjusting the length of their polymethine chain and their functionalization through their end groups or the polymethine chain. Yet, the latter approach remains largely unexplored, with limited information scattered throughout literature. This review focuses on cyanines substituted on their chain, covering their synthesis, properties, and applications and providing an overview of how substituents on their polymethine chain influences their spectroscopic properties, akin to other factors, such as polymethine length and end groups. Lastly, this review illustrates how substituents on the polymethine chain facilitate the application of cyanine dyes in promising research areas.

Multifunctional materials that exhibit both photoluminescence (PL) and liquid-crystalline (LC) properties, referred to as photoluminescent liquid crystals (PLLCs), have garnered considerable interest for applications in fluorescent thermometers and thermosensors. This interest is attributable to their reversible fluorescence switching behavior, driven by aggregated structural changes associated with phase transitions upon heating and cooling. The research group has developed various PLLCs by incorporating fluorescent π-conjugated mesogens into donor–π–acceptor (D–π–A)-type fluorinated tolanes, functionalized with a range of electron-donating and electron-withdrawing groups (EWGs) at the molecular terminal positions. This article introduces a novel class of D–π–A-type fluorinated tolanes featuring an imidazole ring, which functions as an EWG with both steric and electronic effects. These compounds exhibit distinct phase transition behaviors and photophysical properties depending on the chain length of the flexible alkoxy units. Furthermore, for compounds exhibiting any LC phase, the PL behavior in the mesophase is evaluated. The results reveal that phase transitions lead to changes in both the fluorescence wavelength and intensity. These findings demonstrate that nitrogen-containing heterocycles, such as imidazole, are effective EWG units with both steric and electronic contributions. As such, they hold promise for the design of PLLCs for use in PL sensing materials.

This work is devoted to the synthesis, the characterization, and the evaluation of hydroxyapatite-supported ruthenium catalysts, with or without Ba and/or Cs promotion. Thus, a series of catalysts containing Ru, Cs, and Ba was synthesized by the incipient wetness impregnation method. Such catalysts are characterized by different physicochemical methods, providing insights into their properties. These catalysts are evaluated in the ammonia synthesis reaction at 350–500 °C and 10–25 bar. Sample 1Ru/hydroxiapatite (HAP), without promoter, shows a negligible catalytic activity, due to the formation of large Ru nanoparticles, which are not favorable for the formation of ammonia. On the other hand, the addition of Cs and Ba improves the catalytic performance, and Ba is found to be better than Cs. The pretreatment of the barium-containing catalysts under Ar flow at 600 °C is also found to be crucial for the decomposition of barium nitrate into barium oxide, thereby enhancing catalytic activity.

Self-doping has emerged as an effective strategy to tailor the electronic properties of organic materials, especially for n-type semiconductors based on perylene diimide (PDI) and naphthalene diimide (NDI). This review summarizes recent progress in the molecular design and application of self-doped PDI/NDI systems. Representative self-doping groups such as amines, ammonium salts, and other anionic species are introduced and classified. The effects of doping group connecting site selection, including the imide position, aromatic core, and side substitutes, on molecular and electronic properties are then discussed. The application of self-doped PDI/NDI materials in organic electronic devices is also highlighted, covering thin-film solar cells, organic field-effect transistors, and organic thermoelectrics. These materials have shown the ability to improve charge injection, enhance device stability, and regulate interfacial processes. Overall, self-doping is a promising strategy for developing high-performance n-type organic semiconductors. With ongoing improvements in molecular design and device engineering, self-doped PDI/NDI materials are expected to contribute significantly to the advancement of next-generation electronic materials and devices.

Stimuli-responsive systems play a crucial role in biological processes. Research on supramolecular cages formed via noncovalent interactions contributes to the development of receptors that mimic these natural systems. Recently, anion-coordination-driven assembly (ACDA) employing oligourea ligands and trivalent phosphate ions (PO₄³⁻) has emerged as a promising strategy for constructing responsive supramolecular architectures. These assemblies are stabilized through multiple hydrogen bonds and are capable of undergoing structural transformations in response to external stimuli, offering a conceptual framework for understanding flexibility and environmental adaptability in biological contexts. This mini-review highlights the stimuli-responsive properties of anionic self-assemblies, with a focus on systems involving oligourea ligands and PO₄³⁻ ion. Organized by stimulus type, it discusses multistimuli responsiveness, guest-induced transformations, solvent sensitivity, and light-responsive behaviors. Current challenges and identifying future opportunities in the study of ACDA-based stimuli-responsive systems are discussed.

Two Cyanostyryl-guanidiniocarbonyl-pyrrole based amphiphiles are synthesized and examined in detail. In addition to achieving aggregation-induced emission from self-assembly, resulting in nanoparticles, it was found that the observed [2 + 2] photocycloaddition tunes the photophysical properties. The guanidiniocarbonyl-pyrrole component of these hybrid luminophores is shown to bind oxo-anions, such as pyrene-tetracarboxylate, as confirmed by fluorescence lifetime measurements. Moreover, both amphiphiles are used in bio-imaging experiments with HeLa cells, demonstrating effective cellular uptake.

Valorization of biomass-derived chemicals into high-quality compounds and biofuels is enormously fundamental to diminish dependence on fossil-based resources. Furfural is a bio-based valuable compound which can be proficiently upgraded to 4-(2-furyl)-3-buten-2-one (FAc) and 1,4-pentadiene-3-one, 1,5-di-2-furanyl (F₂Ac) via aldol condensation of furfural with acetone. In the present work, efficient Cu-doped MgAl layered double hydroxides (LDH) nanocatalysts are fabricated by coprecipitation and are exploited for furfural conversion to obtained FAc and F₂Ac. The structure–activity relationship is scrutinized by characterizing fresh and spent nanocatalysts via numerous techniques. The good correlation between the amount of weak acidic-weak basic catalytic sites and nanocatalysts performance is established. The superior performance of Cu-0.1 nanocatalyst (Cu-content = 1.85 wt%) in aldol condensation is attributed to the presence of optimum weak acidic sites (0.21 mmol g⁻¹) and weak basic sites (0.36 mmol g⁻¹), synergistic acidic-basic effect, nano-sized Cu(OH)₂ nanoparticles (1.6 nm), high BET surface area (181 m²g⁻¹), and mesoporous architecture of material. Cu-0.1 nanocatalyst delivered 98% FAc selectivity with 100% furfural conversion at 85 °C. Furthermore, at 100 °C, the nanocatalyst gives 55% F₂Ac selectivity with 73% furfural conversion. The catalyst displays good recyclability (7 recycles) and stability. Plausible mechanistic pathway for transformation of furfural to FAc and F₂Ac is proposed.