Advanced Composites and Hybrid Materials最新文献

The advancement of scalable patterning techniques is essential for optimizing charge transport, enhancing conductivity, and improving the performance of polymer organic semiconductor (OSC) devices. Conventional photolithography encounters significant challenges in the micro-/nano-fabrication of polymeric materials due to insufficient chemical orthogonality with photoresists. Emerging methodologies, including inkjet printing, meniscus-guided coating, and innovative lithography techniques, have partially mitigated these issues but still frequently encounter limitations related to material versatility and process complexity. In response to these challenges, we developed the nano-aluminum micro-pattern infusion (NAMP-I) technique, which enables the precise patterning of solution-processed organic OSC films on hydrophobic perfluoro(1-butenylvinylether) polymer (CYTOP) dielectric layers. This innovative method employs aluminum-nanoparticle metal films to initiate and control OSC growth, thereby enhancing interfacial quality through the formation of aluminum oxide (Al₂O₃) and improved hydrogen bonding interactions. Devices fabricated with the NAMP-I technique demonstrate low turn-on voltage, minimal hysteresis, and high carrier mobility of up to 1.85 cm²V⁻¹ s⁻¹. NAMP-I enables high-performance, solution-processed OFETs with sharp on/off switching, demonstrating significant potential for integrating advanced functional materials into flexible and high-density electronic devices.

We demonstrate a straightforward and effective method to achieve uniform infiltration of optical sensitizers into nitrocellulose aerogels using a sol–gel method followed by supercritical carbon dioxide drying. The optical sensitizers employed in this study include gold nanoparticles capped with self-assembled monolayers of hydroxyl and/or carboxylic functional groups as well as carboxylated multi-walled carbon nanotubes. The resulting robust, monolithic aerogels were characterized in detail by using scanning electron microscopy, specific surface area measurements, differential scanning colorimetry, and laser initiation and combustion. Although the composite aerogels exhibited similar surface areas, morphologies, and microstructures as pure nitrocellulose aerogels, they exhibited increased sensitivity to laser stimuli and demonstrated improved combustion properties compared to pure nitrocellulose aerogels. We attribute these enhanced performances to the possible increase in photothermal conversion and thermal conductivity facilitated by the incorporation of optical sensitizers within the aerogels.

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The incorporation of optical sensitizers into the aerogels enhanced their sensitivity to laser stimuli and accelerated their combustion rate, owing to the superior photothermal conversion and improved thermal conductivity provided by the sensitizers.

Thermoplastic polyamide elastomers (TPAEs) possess remarkable characteristics such as high-temperature tolerance, superior mechanical properties, and the shape memory effect (SME). The current study develops a type of TPAE with SME by fabricating the long carbon chain polyamide (PA512) and polyethylene glycol (PEG) through a two-step melt polycondensation process. The properties of TPAEs were investigated by varying the PA512 prepolymer’s molecular weight and the amount of PEG. During synthesizing TPAEs with SME, the crucial balance of COOH and OH groups was skillfully achieved by introducing biobased butanediol (BDO). The chemical structure of TPAEs is confirmed by FTIR and ¹H NMR tests. By meticulously engineering the PA512 molecular weight and refining the PEG domain content, TPAEs are fabricated to elongate at a break of 592.4% at room temperature while maintaining a tensile strength of 23.1 MPa. TPAEs, which have two distinct melting temperatures, exhibit microphase separation between the PEG and PA512 domains. This phenomenon is further corroborated by the scanning electron microscope (SEM) test. Additionally, TPAEs exhibit the SME, which can fix a temporary shape when heated, twisted, and cooled, and then recover to its original shape upon reheating, with TPAE230 demonstrating the most outstanding shape memory effect, achieving an average shape fixity ratio of 91.2% and a shape recovery ratio of 94.4%. This behavior is attributed to the fixing force provided by the PEG domains and the entropy elasticity of the physically cross-linked PA512 domains. The findings indicate that TPAEs exhibit enhanced SME in response to temperature changes. Leveraging this property, developing a temperature-sensitive device holds promise for breakthroughs in elastic temperature sensing applications.

Hematite (α-Fe₂O₃) is considered a highly promising candidate material for photoelectrochemical water splitting (PEC-WS) due to its suitable band gap and band edge location. Nevertheless, enhancing PEC-WS performance through the surface construction of low-cost, highly efficient, and stable electrocatalysts still remains a challenge. This work presents a facile strategy to fabricate α-Fe₂O₃ photoanodes modified with the metal–organic framework films doped with iron-group elements (Fe, Co, and Ni), which forms abundant active sites and leverage bimetallic synergistic effects. The optimal photocurrent density of FTO/Sn@α-Fe₂O₃/MIL-125/Co photoanode achieves 1.97 mA/cm² at 1.23 V_RHE, which is 2.3 times that of the pure α-Fe₂O₃ photoanode. The on-set potential exhibits a cathodic shift of 0.1 V. The MIL-125 catalyst with Co doping exhibits the most excellent PEC-WS performance among the three dopants (Fe, Co, and Ni), which can be primarily attributed to more abundant active sites, the lower photogenerated carrier recombination, and the enhanced charge separation and transfer efficiency.

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Antibacterial hydrogels have gained significant attention as appealing materials, but their weak structures largely limit their practical applications. In this study, chitosan (CS)-based double-network antibacterial hydrogels were developed, where polyacrylamide (pAAm) attributed to the high mechanical property and [2-(methacryloyloxy)ethyl]trimethylammonium chloride (MTAC) exerted the strong antibacterial activity, structured as CS/p(AAm-MATC). The structure and morphology of hydrogels with a ratio of pAAm and MTAC of 5:5 were preferred and analyzed using scanning electron microscopy, Fourier transform infrared spectroscopy, solid-state NMR spectroscopy, and X-ray diffraction, confirming the successful synthesis. The hydrogels had remarkable compression resistance, withstanding a high strain of 85% with excellent shape recovery. Rheological tests revealed that the samples exhibited characteristic behaviors of hydrogels, with the storage modulus surpassing the loss modulus and increasing with the angular frequency. Furthermore, the composite hydrogels had excellent antibacterial efficacy against Gram-positive (Listeria monocytogenes) and Gram-negative (Escherichia coli) bacteria, mainly attributed to the presence of quaternary ammonium groups in MTAC polymers. These hydrogels, with outstanding mechanical and antibacterial properties, hold promising potential for diverse applications, such as wastewater treatment.

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A tough double-network hydrogel is created by a combination of physical and chemical crosslinking methods, exerting high mechanical and enhanced antibacterial properties.

The failure of wound healing is majorly attributed to uncontrolled bleeding and bacterial infections. However, developing a wound plaster that can stop bleeding, resist blood extravasation, and realize directional transportation of drugs to promote wound healing remains a significant challenge. Herein, a superhydrophilic/hydrophobic polyvinyl alcohol/chitosan/silver@Thermoplastic polyurethane (PVA/CS/Ag@TPU) Janus membrane with structural and wettability gradients is developed. In this newly developed membrane, water is absorbed from blood via the superhydrophilic layer, which is attached to the wound, and the charge interactions between platelets and the introduced chitosan (CS) promote blood clotting. The capillary pressure resistance (∆p > 0) of the superhydrophilic layer toward the hydrophobic layer prevents blood permeation, thereby reducing blood loss. The favorable ∆p (< 0) of the membrane based on its structural and wettability gradients can realize the directional transportation of drugs that promote wound healing from the hydrophobic to the superhydrophilic layer. The incorporation of CS and silver endows the Janus membrane with intrinsic antibacterial properties (99.9%). The formation of the hydrated layer on the hydrophilic layer imparts a resisting effect, further endowing the membrane with antiadhesion and antibacterial properties. Experiments involving mice with full-thickness skin wounds revealed that the wound-healing rate increased from 87.65% to ~ 100% when the Janus membrane was loaded with the prehealing drug. Moreover, the dressing accelerated wound healing, regenerated epidermal and granulation tissues, promoted collagen formation, and reduced scar size. Thus, this gradient design strategy opens an avenue for the development of next-generation wound dressings.

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Cancer, as the leading cause of death worldwide, has been constantly increasing in mortality every year. Among several therapeutics, nanoscale compounds showed promising results in overcoming cancer diseases. There are numerous types of research on the paramagnetic nanoparticles of iron oxide, which cause apoptosis and cancer cell death. In this study, cobalt/zinc/ferrite nanoferrofluid composites (~ 39 nm) were synthesized and decorated with chitosan to enhance the cell entry for potential applications in cancer therapy. The neat and chitosan-adorned cobalt zinc ferrite nanoferrofluid composites (~ 94 nm) displayed superparamagnetic properties. The nanocomposite exhibited anti-cancer activity against WEHI164 cancer cells in a dose- and time-dependent manner. The chitosan-coated nanocomposite was found to induce oxidative stress in WEHI164 cancer cells, as indicated by reactive oxygen species (ROS) production. Furthermore, DNA damage was indicated in WEHI164 cancer cells after exposure to chitosan-coated nanocomposites. Chitosan-coated nanocomposites promoted dendritic cell maturation by inducing the release of interleukin-6 proinflammatory cytokines. According to the results and ancillary studies, superparamagnetic nanoparticles coated with chitosan can be considered an effective and promising treatment for the destruction of cancer cells.

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Summary: Chitosan decorated cobalt zinc ferrite nanoferrofluid composites was fabricated for potential cancer hyperthermia therapy with high biocompatibility.

Domestic wastewater contains trace amounts of organic pollutants that are difficult to remove, such as antibiotics and dyes, so effective degradation technologies need to be found. Therefore, we report the fabrication of a novel Z-scheme MIL-125(Ti)/GO photocatalyst by an in-situ growing method. The photodegradation experiment showed that MIL-125(Ti)/GO degraded TC by 81.1% at 5% GO addition, which is 1.7 and 3.8 times higher than MIL-125(Ti) and GO, respectively. The degradation rate reached 0.0201 min⁻¹, 3.3 times and 8.1 times higher than MIL-125 (Ti) and GO, respectively. The study shows that GO and MIL-125(Ti), as electron donors and electron acceptors, respectively, form a Z-scheme heterojunction structure, which effectively improves the photocatalytic performance of MIL-125(Ti). MIL-125(Ti)/GO has excellent structural stability and reusable availability, and the main reactive radicals are ·O⁻₂ and h⁺. This study provides new insights into the design and fabrication of MIL-125 (Ti) derivatives as photodegrading organic pollutants.

Structural polymeric nanohybrids is presently a popular topic and can be conceived for numerous functional applications, including the pH-sensitive oral colon-targeted drug-delivery system. In this paper, a brand-new Janus core@shell (JCS) nanostructure was fabricated using a trifluid electrospinning, in which three polymers and a model drug 5-fluorouracil (5-FU) were elaborately and intentionally positioned. In the structural hybrids, the pH-sensitive polymer hydroxypropyl methyl cellulose acetate succinate was located in the common shell layer, and the 5-FU-loaded ethyl cellulose (EC) and polyethylene oxide (PEO) were organized in a side-by-side manner in the core sections. The JCS fiber had a fine linear morphology with a multiple-chamber structure and a shell thickness of about 24 nm. The drug presented in the fibers in an amorphous state, owing to the secondary intermolecular interactions between EC and 5-FU. The ex vivo adhesion experiments suggested that the JCS fibers could stick firmly to the intestine membranes. In vitro dissolution tests showed the JCS fibers released only 7.8% ± 3.5% of the loaded 5-FU in an acid condition. In vivo gavage administration verified that the JCS fibers effectively promoted the absorbance of 5-FU in a synergistic manner, better than the double-layer core–shell and Janus nanofibers, and near fourfold than the drug solutions as a control. The present protocol opens a new way for developing novel multifunctional nanomaterials with the JCS nanostructure as a powerful supporting platform.

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