Search Results (852)

Organic-type solar cells containing an active layer of block copolymer donor PTB7-Fx (x = 0, 20, and 100), based on benzo [1,2-b:4,5-b’]dithiophene and variably fluorinated thieno [3,4-b]thiophene units, and fullerene acceptor [6,6]phenyl-C₇₁-methylbutyrate, were constructed. The active layer thin film of the solar cells was obtained from a dichlorobenzene solution at an established concentration via spin-coating of the donor–acceptor mixture in the presence of solvent additives such as 3% diiodooctane and 1% triethyl phosphate. Organic photovoltaic elements with normal device architecture were prepared on glass substrates using an indium tin oxide anode, a spin-coated hole transporting layer of poly(ethylene dioxythiophene):polystyrenesulfonate, the aforementioned active layer, followed by an electron transporting layer of zinc oxide nanoparticles, and finally a magnetron sputtered silver (Ag) top-electrode. The optical properties, thin film morphology, and the thickness of the active layers were investigated. Additionally, current density–voltage characteristics and impedance spectra of photovoltaic devices were measured. It was found that PTB7-Fx:PC₇₁BM-based solar cells processed in the presence of two types of solvent additives, diiodooctane and triethyl phosphate, with a sputtered Ag top-electrode display similar absorption and quantum efficiency spectra, as well as comparable current density–voltage characteristics and efficiencies to the same devices fabricated without additives. The diiodooctane solvent additive preferably dissolves the fullerene component and has a positive effect on fill factor enhancement, impedance spectra improvement, and amelioration in charge carrier transport and collection, whereas the triethyl phosphate solvent additive preferentially dissolves the copolymer donor and has a more pronounced impact on the refined morphology of the thin film active layers. Full article

Three ethynyl-extended benzanthrone derivatives with benzonitrile (Dye A), thiophene (Dye B), and methyl propiolate (Dye C) as substituents were synthesized and investigated to illustrate structure–property relationships governing their nonlinear optical (NLO) behavior. The third-order nonlinear absorption and refractive index of three dyes were studied using open- and closed-aperture z-scan measurements under 532 nm continuous-wave laser excitation. All dyes exhibited reverse saturable absorption dominated by two-photon absorption, with Dye A showing the highest nonlinear absorption coefficient (βeff = 2.3 × 10⁻⁵ cm/W) and two-photon response, attributed to its extended conjugation and smaller HOMO−LUMO gap (6.45 eV). Closed-aperture Z-scans revealed strong nonlinear refraction (n₂), with the thiophene-substituted Dye B displaying the largest n₂ (14.8 × 10⁻⁹ cm²/W) and third-order susceptibility (χ³ = 3.1 × 10⁻⁶ esu). The evaluated optical switching figures of merit met the requirements for all-optical switching and optical limiting. DFT and TDDFT calculations demonstrated that donor substitution and conjugation length govern electronic structure, charge transfer character, and global reactivity descriptors. Enhanced electronic softness and hyperpolarizability in Dye B further support its superior refractive nonlinearity. These results establish clear structure–property correlations and highlight donor engineering as an effective strategy for developing organic nonlinear optical and photonic materials. Full article

This study demonstrates the high efficiency and selectivity of p-toluenesulfonic acid-based deep eutectic solvents (DESs) for simultaneous extractive denitrogenation (EDN) and desulfurization (EDS) of model fuel. Three DESs—TBPB:PTSA, TBAB:PTSA, and ChCl:PTSA (1:1 molar ratio)—were synthesized and evaluated for their effectiveness against representative heteroaromatic pollutants: thiophene, dibenzothiophene, pyridine, and carbazole. The phosphonium-based TBPB:PTSA exhibited the highest extraction performance, achieving over 96% removal of nitrogen species and up to 85% removal of sulfur species at 40 °C. Increasing the temperature enhanced desulfurization by reducing viscosity, thereby improving mass transfer kinetics. Additionally, a 3:1 ratio of DES to fuel provided an optimal balance between solvent economy and operational efficiency. Denitrogenation was driven by strong acid–base protonation facilitated by PTSA, while desulfurization was governed by π–π and dispersion interactions, modulated by the hydrophobicity of the cations. The DES achieved nearly quantitative nitrogen removal and satisfactory sulfur extraction after three reuse cycles, while multistage operation enabled complete purification within four extraction steps. ¹H NMR analysis confirmed that no DES components were found in the raffinate phase, verifying the immiscibility and stability of the solvent. These results indicate that TBPB:PTSA is a robust, regenerable, and environmentally benign solvent, effectively enabling simultaneous EDN–EDS of hydrocarbon fuels and positioning it as a promising green alternative to traditional hydrogen-based refining methods. Full article

We report a π-extended N-phenylphenothiazine dye bearing thiophene substituents, designed to address the practical compromise between long-wavelength near-infrared (NIR) absorption and the isolability of a stable radical cation state. The target compound was synthesized via Suzuki–Miyaura cross-coupling and exhibited good solubility in common organic solvents. Cyclic voltammetry in dichloromethane showed a reversible one-electron oxidation at E⁰ = 0.19 V vs. Fc/Fc⁺. Chemical oxidation afforded the corresponding radical cation, which showed an intense NIR absorption maximum at 910 nm. DFT calculations support thiophene-induced narrowing of the HOMO–SOMO gap and predict a pronounced bathochromic shift of the main absorption band. The radical cation was isolated as a stable PF₆⁻ salt and readily processed into spin-coated films, which retained strong NIR absorption and remained stable for months under ambient conditions. Full article

This study investigates lignite, long-flame coal, coking coal, and anthracite to elucidate the rank-dependent evolution of coal macromolecular structure and pore systems. Elemental/proximate analyses, FTIR, XPS, ¹³C NMR, and low-temperature N₂ adsorption–desorption, combined with BET, BJH, and DFT models, were employed to quantify structural parameters, characterize pore-size distributions, and establish representative macromolecular models. The results show that coalification is accompanied by progressive aromatization and polycondensation. Low-rank coal contains abundant hydroxyl, carboxyl, and aliphatic side-chain structures, exhibiting low aromaticity and weak aromatic-ring condensation. With increasing rank, oxygen-containing groups and aliphatic chains are progressively removed, while aromatic carbon content and the bridgehead-to-peripheral carbon ratio increase markedly. High-rank coal is dominated by highly condensed aromatic lamellae, with lower molecular polarity and enhanced structural ordering and graphitization. Meanwhile, N and S occurrence modes evolve from edge-related reactive species to more stable heterocyclic configurations, reflected by increasing graphitic N and thiophenic S contents. Pore structures also change systematically: low-rank coal is characterized by open, multimodal mesopores; intermediate-rank coal shows compaction and mesopore collapse; and high-rank coal becomes micropore-dominated with a relatively closed network. The U-shaped variation in micropore and mesopore volumes with rank indicates coupled macromolecular polycondensation and pore reconstruction, providing a structural basis for spontaneous combustion propensity and coalbed methane occurrence. Full article

Design and fabrication of high-performance organic semiconductors are still challenging. Here, we designed new D-(A)n type zinc porphyrin end-capped ethynylene-7-(4-hexyl-thiophen-2-yl)-2,1,3-benzothiadiazole (EBTT) oligomers by linking 5,10,15-trisphenyl porphyrin zinc (ZnTPP) with length-variable EBTT oligomers (at the 20-position of porphyrin) [ZnTPP(EBTT)_n (n = 1–6)]. The influence of oligomer length on molecular structures, orbital energies, electronic absorption spectra, ionization energies, electronic affinities, and reorganization energies was systematically studied through density functional theory. The charge-carrier mobility of the simulated crystals and the power conversion efficiencies (PCE) using PCBM as the accepter were also predicted. ZnTPP(EBTT)₆ show excellent hole/electron mobility of 76.161/9.395 cm²V⁻¹s⁻¹ and extremely high PCE of 25.45%. This work would have significance for the design and synthesis of organic semiconductor materials with large charge-carrier mobility and high PCE performance. Full article

Donor–acceptor (D-A)-type conjugated porous polymers (CPPs) have emerged as highly competitive photocatalysts for aerobic oxidation reactions. Herein, we rationally design and synthesize a series of D-A structured photocatalysts by employing dibenzothiophene-S, S-dioxide (BTDO) as the acceptor unit, and 4,8-bis(thiophen-2-yl) benzo [1,2-b:4,5-b’] dithiophene (DBD) and pyrene (Py) as the donor units. The effects of acceptor content on the optoelectronic and photocatalytic properties are systematically investigated. With the gradual increase in BTDO proportion and the decrease in pyrene content, the photocatalysts exhibit gradually narrowed band gaps, significantly promoted charge separation efficiency, and broadened visible light absorption range. Among the five as-prepared photocatalysts, DBD-T displays superior catalytic performance toward blue light-driven aerobic oxidation. Under mild conditions, benzyl sulfide and benzyl amine are selectively converted into benzyl sulfoxide and benzyl imine with a high conversion efficiency up to 96%. Moreover, DBD-T shows good universality toward a wide range of substrates, together with excellent recyclability and long-term stability. This work demonstrates that enhancing the electron-withdrawing capability of the acceptor unit represents a feasible and effective strategy to boost the photocatalytic performance of D-A-type conjugated polymers. Full article

Introduction: Osteosarcoma (OS) is the most common primary malignant bone tumor in children and young adults, with poor prognosis due to relapse, metastasis, and chemoresistance. The search for novel metal-based therapeutics has highlighted copper complexes as promising candidates. Here, we report the in vitro and in vivo antitumor activity of a tetranuclear Cu(II)-hydrazone complex (Cu₄L₄) derived from (E)-5-chloro-N′-(2-hydroxy-3-methoxybenzylidene)thiophene-2-carbohydrazide. Results: Cytotoxic assays on MG-63 OS cells revealed potent activity with an IC₅₀ of 0.50 ± 0.04 µM, significantly surpassing its free ligand (IC₅₀ = 13.9 ± 1.6 µM) and cisplatin (IC₅₀ = 39.0 ± 1.8 µM). This tetranuclear complex outperforms mononuclear Cu-hydrazones analogs (e.g., 4-fold vs. CuHL1, 2-fold vs. CuHL2, 5-fold vs. CuHL3, 17-fold vs. CuHL4,), and Cu₄L₄ also exhibits reduced clonogenic survival, induces reactive oxygen species production, and promotes late apoptosis as a main mechanism, being the main mechanism of action involved in anticancer activity. In multicellular tumor spheroids, the complex maintained strong cytotoxicity (IC₅₀ = 4.11 ± 0.12 µM), impaired spheroid integrity, and markedly inhibited cell migration at sub-IC₅₀ concentrations. The tetranuclear architecture confers markedly enhanced antitumor activity relative to the corresponding mononuclear Cu–hydrazone complexes (e.g., 2-fold vs. CuHL1, 4-fold vs. CuHL2, 2-fold vs. CuHL3). In a xenograft model, sustained administration of Cu₄L₄ (2 mg/kg, i.p., twice weekly) inhibited tumor growth by 43.6%, reduced mitotic index, and increased necrotic area without significant systemic toxicity. Conclusions: Overall, Cu₄L₄ displayed potent and selective antitumor activity against OS cells in 2D, 3D, and in vivo models, underscoring copper–hydrazone complexes as promising scaffolds for the development of new therapies against OS. Full article

Neurodegenerative disorders (NDs), such as Alzheimer’s disease and Parkinson’s disease (PD), represent a significant challenge for ageing populations, with their prevalence increasing worldwide. Elevated human Monoamine Oxidase B (hMAO-B) activity has been related to neurodegenerative progression, where it contributes, among others, to oxidative stress and neuroinflammation. The identification and optimization of selective hMAO-B inhibitors is therefore pivotal in addressing the progression of NDs. In this work we introduced 2-aroylbenzothiophene analogues as promising agents to mitigate neurodegeneration. The synthesized compounds were screened against hMAO-A and hMAO-B, identifying compounds 4, 11, and 12 as the most promising. In vitro studies in hGF and SH-SY5Y cells revealed distinct toxicity profiles, with compound 4 being the least tolerated at 100 µM. ROS generation was investigated as a possible mechanism underlying this toxicity. Compounds 4 (12.5 µM), 11, and 12 (100 µM) were further evaluated for neuroprotective effects against 6-hydroxydopamine (6-OHDA)-induced toxicity in SH-SY5Y cells, showing a modest neuroprotective effect after 72 h at a sub-toxic 6-OHDA concentration (250 µM), comparable to the clinically used hMAO-B inhibitor (R)-(−)-Deprenyl at 100 µM. Finally, molecular modelling studies revealed that compound 4 establishes key stabilizing interactions within hMAO-B, accounting for its high inhibitory potency and selectivity over hMAO-A. Full article

Two approaches are described for construction of a screen-printed planar electrode (SPE) for potentiometric determination of iodide ion. The first, involves preparation and application of iron(II) bathophenanthroline tetraiodoplumbate complex ([Fe(bphen)₃][PbI₄]), as a sensitive and selective electroactive sensing material in a potentiometric electrode for iodide determination. The second is the use of a nano-sized poly(aniline-co-thiophene) (PANI-co-PT) as a solid-contact material in a planar miniaturized configuration. The SPE displays a Nernstian response for iodide ion with a calibration slope of −58.81 ± 0.69 mV/decade (R² = 0.9998) over a wide concentration range (9.17 × 10⁻⁷–6.94 × 10⁻³ mol/L), low detection limit (6.09 × 10⁻⁷ mol/L), rapid response time (5.0 ± 1.0 s) and long-life span (75 ± 3.0 d). The use of PANI-co-PT solid-contact layer significantly improves the ion-to-electron transduction, eliminates the formation of undesired thin water layer between the sensing membrane and the conducting substrate, prevents membrane delamination, enhances potential stability with a significantly reduced potential drift (8.32 ± 0.12 µV/min) and displays high redox capacitance (2.560 ± 0.040 mF). Water contact angle measurements confirm the increased hydrophobicity of the modified membrane electrode (from 44 ± 0.8° to 93 ± 1.4°) and demonstrate the membrane ability to repel moisture and further stabilize the sensor response. The proposed sensor is successfully integrated into a flow injection analysis (FIA) system to enable real-time and continuous iodide monitoring with high precision, high sample throughput and applicability for quality control of pharmaceuticals and environmental monitoring. Full article

Stretchable semiconductors capable of maintaining electrical performance under large mechanical deformation are essential for reliable wearable electronic devices. However, polymer semiconductors often suffer from electrical degradation when subjected to tensile strain. In this study, electrical stability under strain was achieved by using a rubber-blended poly(2,5-bis(2-octyldodecyl)-3,6-di(thiophen-2-yl)diketopyrrolo[3,4-c]pyrrole-1,4-dione-alt-thieno[3,2-b]thiophene) (DPPT-TT) polymer semiconductor based on a conjugated polymer/elastomer phase separation-induced elasticity (CONPHINE) structure. Unlike most previous studies on fully stretchable thin-film transistors (TFTs), which primarily report overall performance changes under mechanical strain, this work systematically identifies the dominant origin of electrical performance degradation through a stepwise electrical analysis encompassing the gate insulating layer, the semiconductor layer, and complete devices. Bottom-gate top-contact (BGTC) and bottom-gate bottom-contact (BGBC) devices were fabricated on rigid Si/SiO₂ substrates to examine the intrinsic properties of the DPPT-TT/styrene-ethylene-butylene-styrene (SEBS) CONPHINE film. As a result, the device exhibits 90% mobility retention even at 100% tensile strain applied parallel to the charge transport direction. Quantitative resistance analysis using the Y-function method reveals that variations in channel resistance play a dominant role in strain-induced performance degradation, whereas changes in contact resistance contribute only marginally. These findings demonstrate that stabilizing channel resistance, rather than contact resistance, is important for achieving high mobility retention under large mechanical deformation, thereby providing concrete and quantitative design guidelines for reliable stretchable TFTs. Full article

Organic photovoltaic materials and nonlinear optical materials share inherent commonalities in molecular characteristics—such as strong light absorption, high charge carrier mobility, and tunable energy levels. Therefore, this study selects a bithiophene-fused ring system with photovoltaic application potential as the research subject. Using TTTTB6-2CHO (TB1) and IDTTB6-2CHO (TB2) as comparative molecules, their nonlinear optical properties in the near-infrared region were systematically investigated. Transient absorption spectroscopy results demonstrate that TB1 exhibits strong and persistent excited-state absorption within the spectral range of 650–900 nm, endowing it with excellent two-photon absorption performance (a cross-section of up to 5591 GM at 650 nm) and an ultralow optical limiting threshold (0.00147 J/cm² under 800 nm femtosecond laser irradiation). The findings of this study not only confirm the feasibility of developing nonlinear optical materials from photovoltaic candidate molecules but also highlight the effectiveness of the “thiophene-for-benzene substitution” strategy in significantly enhancing optical nonlinearity. These results provide valuable design principles for the development of multifunctional organic optoelectronic materials, particularly for application scenarios such as laser protection. Full article

Background/Objectives: Multidrug resistance (MDR) remains a critical global public health concern, compromising the efficacy of currently available antibiotics. As the development of new antibiotics offers limited long-term solutions, alternative approaches such as efflux pump inhibition have gained attention. This study reports the development of nanostructured lipid carriers (NLCs) co-loaded with Norfloxacin (NOR) and the efflux pump inhibitor 2-amino-thiophen-6CN-Ethyl, to modulate NOR activity against resistant Staphylococcus aureus strains overexpressing efflux pump genes. Methods: NLCs were produced via the hot emulsion method followed by sonication. The formulations were characterized for encapsulation efficiency (EE%), particle size, polydispersity index (PDI), zeta potential, X-ray diffraction (XRD), infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), in vitro release kinetics, and stability. Antibacterial activity was evaluated against S. aureus 1199B and K2068 strains. Results: The NLC formulation containing norfloxacin and 6CN-Ethyl (NLC10NOR + 106CN) demonstrated high EE% for both compounds (99.50% for 6CN-Ethyl and 90.91% for NOR) and physicochemical stability over 60 days (particle size < 255 nm, PDI < 0.3, zeta potential < −20 mV). Structural analyses confirmed amorphization and effective encapsulation of the active constituents. Antibacterial assays showed that NLC10NOR + 106CN significantly increased NOR activity compared to the free drug and physical mixture; the effect in 1199B was notably superior to the NOR + CCCP (carbonyl cyanide m-chlorophenylhydrazone) combination. Conclusions: These findings highlight the potential of NLC-based co-delivery systems as innovative strategies to overcome bacterial resistance, particularly through efflux pump inhibition enhancing antibiotic efficacy. Full article

A new series of promising and easily accessible antiproliferative agents based on cycloruthenated imines of benzene and thiophene carbaldehydes has been developed and fully characterized using UV-Vis spectroscopy, X-ray diffraction, NMR, HRMS, and cyclic voltammetry. The biological activity of these compounds was tested against A2780, cisplatin-resistant A2780, and HEK293 cell lines, and they exhibited nanomolar IC₅₀ values. They also showed a selectivity index of up to 2.5, indicating their potential as promising antiproliferative compounds. Full article