ChemPlusChem最新文献

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.

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.

Benzothiazoles, including the cationic thioflavin T and its variants, are of immense interest because of their therapeutic potential and applications as biomolecular fluorescence probes. This study investigates the photophysics of an interesting benzothiazole derivative, TEG-BTA-2, that combines a neutral thioflavin T type of moiety (BTA-2) with a tetraethylene glycol chain (TEG). Unlike thioflavin T, TEG-BTA-2 is highly fluorescent and shows multiple prototropic transformations. Monoprotonated TEG-BTA-2 is found to exist in two isomeric forms, each having characteristic absorption, emission, and fluorescence lifetimes. Furthermore, TEG-BTA-2 shows strong affinity toward the cavitands α-, β-, and γ-cyclodextrins (CDs). The binding constants of TEG-BTA-2 with the cavitands are considerably higher than that of thioflavin T, which is attributed to its neutral charge and favorable hydrophobic/H-bonding interactions provided by the TEG chain. Interestingly, it is found that the size of the macrocyclic cavity plays a pivotal role in controlling the fluorescence response of TEG-BTA-2 due to formation of complexes with different stoichiometries. In contrast to the fluorescence enhancement observed with αCD and βCD, the interaction of TEG-BTA-2 with γCD leads to fluorescence quenching. These results provide valuable insights for development of thioflavin T-inspired benzothiazole molecules as fluorescent markers and diagnostic agents.

An additive-free, low-viscosity polyalphaolefin (PAO) has been oxidized under pure oxygen at elevated pressure and temperature. This biodegradable PAO base oil is a promising candidate for use as a motor-gear lubricant in electrical drive systems. The oxidation behavior is systematically investigated to evaluate its thermal stability and long-term performance. Rheological measurements are performed to assess viscosity, water content is quantified, tribological tests determine the coefficient of friction, and Fourier-transform infrared spectroscopy is used to monitor chemical changes during oxidation. All analytical methods consistently revealed a two-step oxidative degradation process. It is proposed that the first stage involves the formation of carbonyl compounds and water without compromising lubrication properties, while the second stage-triggered by hydrolysis of oxidation products-leads to chain scission and initiates the desired degradation. This two-stage mechanism is discussed in the context of technological functionality and sustainability requirements for next-generation electric drive lubricants.

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.

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.

Research and applications relevant to human health are enabled by detergent chemistry. A multifaceted overview of this field is yet missing. To close this gap, this topical collection provides an overview of recent advances in detergent chemistry covering progress in synthesis, supramolecular characterization, and application. Our collection shows that detergent chemists operate usually interdisciplinary. Connecting molecular structures of detergents with properties relevant to applications is at the center of scientific exploitation. Detergent chemists deliver solutions to research and industry that aim at securing well-being, hygiene, and new pharmaceuticals.

Gold(III) complexes have gained prominence as photofunctional materials due to their tunable photophysical properties and potential in advanced optoelectronic applications. While traditionally gold(III) complexes have been known to exhibit phosphorescence emission, recent advancements have revealed that gold(III) complexes can also display thermally activated delayed fluorescence (TADF), enabling near-unity internal quantum efficiencies and full exciton utilization. However, gold(III) biscyclometalated complexes incorporating trifluoromethyl groups and displaying TADF-type emission have been lacking. We report biscyclometalated gold(III) C^N^C complexes incorporating electron-withdrawing trifluoromethyl (CF₃) groups with TADF-type emission. Both aryl and alkynyl ligands were employed to investigate the balance between structural stability and donor-acceptor spatial separation. Detailed photophysical studies reveal TADF-type emission behavior in these complexes with quantum yields as high as 70% in solution with high radiative rates in the order of 10⁶ s^-1. These complexes exhibit promising photophysical properties suitable for high-efficiency organic light-emitting diode applications, providing valuable design strategies for next-generation TADF emitters based on gold(III) scaffolds.

The removal of nanoplastics (NPs) from aquatic environments remains a significant challenge due to their persistence and potential ecological risks. Flocculation, together with coagulation and sedimentation, is widely used as a phase-separation technique in industrial water treatment. In this study, alginate (ALG)-enhanced sedimentation of polystyrene (PS) NPs under varying CaCl₂ concentrations was investigated via turbidimetric analysis. The destabilization mechanism was assessed through floc morphology, zeta potential measurements, attenuated total reflectance-Fourier transform infrared spectra, and scanning electron microscope/energy-dispersive X-ray spectroscopy analysis. The rheological properties of ALG solutions in the presence of CaCl₂ were expressed as complex viscosity. To better simulate environmentally relevant conditions, we employed a novel PS-NP dispersion without commercial stabilizers. The results show that ALG effectively destabilizes the system at moderate and high coagulant ionic strengths, with an optimal dosage of 10 ppm ALG. Calcium ions can interact with ALG chains through the formation of intermolecular complexes. At the highest CaCl₂ concentration, changes in the system's rheological properties altered floc morphology and delayed sedimentation. This study highlights the potential of natural bioflocculants such as ALG for removing PS-NPs from calcium-rich waters and reducing reliance on synthetic coagulants.

The precise and noninvasive detection of thiosulfate, an essential antidote for cyanide poisoning, is critical for both clinical toxicology and environmental monitoring. In this work, the development of an electroactive copper-cyanurate (Cu-CYA) coordination polymer, engineered as a highly sensitive and selective electrochemical sensor for thiosulfate detection in biological fluids, is reported. The sensor material is synthesized via a straightforward coordination-driven self-assembly process, yielding a porous framework with abundant active sites, excellent redox properties, and superior electron transfer capability. Comprehensive physicochemical characterization confirms the structural integrity and favorable interfacial kinetics of the Cu-CYA/graphite pencil electrode (GPE) sensor. Cyclic voltammetry and differential pulse voltammetry analyses reveal a robust and linear response to thiosulfate concentrations ranging from 100 to 500 nM, with a remarkable sensitivity of 2.94 µA cm^-2 nM^-1 and an exceptionally low limit of detection of 0.32 nM. The sensor exhibits high selectivity against potential interferents and maintains 93.3% of its initial response after 30 days, underscoring its long-term functional reliability. Notably, real sample analysis using human saliva demonstrates a mean recovery of 97.5%, validating the sensor's practical applicability in complex biological matrices. This study establishes Cu-CYA as a powerful electrochemical sensing platform for thiosulfate monitoring, offering new prospects for portable diagnostics in healthcare and environmental safety.