Advanced Composites and Hybrid Materials最新文献

The top-down preparation of graphene nanoplatelets (GNPs) from graphite using different processing methods yields GNPs with very different structural and morphological properties. Hitherto, the role the processing history of the precursor graphite has on the resultant GNPs and their efficacy as a functional filler for rubbers is poorly understood, particularly with regard to the formation of an interphase region between the filler and matrix and the mechanical and cure properties of styrene-butadiene rubber (SBR) compounds. Two types of GNPs (GNP1 and GNP2), with distinct morphology, crystallinity, defect density, and lateral dimensions, were incorporated into SBR to investigate the impact of GNP type on filler dispersion, filler-filler, and filler-rubber interactions on the resulting compound performance. The inclusion of GNP2, with higher crystallinity, larger lateral dimensions, and an absence of defects in the form of folds/bends, significantly outperforms GNP1 in terms of bound rubber content, crosslink density, and mechanical properties. The addition of GNP2 to SBR resulted in a 55% increase in modulus at 100% strain, 50% increase in tensile strength, and a 25% increase in elongation at break compared to the carbon black (CB) filled equivalent. This enhanced reinforcement is derived from the formation of an extensive GNP2–GNP2 network and improved filler-rubber interactions. GNP2 was more highly dispersed in the SBR matrix resulting in more effective curing, reduced crack propagation, and enhanced abrasion resistance in comparison to traditional carbon black filled SBR (RCB). This work provides valuable insights into the impact of graphite processing on the structural properties of GNPs and highlights the importance these properties play in reinforcing SBR.

α-Hemolysin, produced by Staphylococcus aureus, is one of the most potent secreted toxins. It directly destroys host cell membranes by forming transmembrane pores, ultimately leading to severe health complications. Accordingly, there is an urgent need to rapidly detect contaminated samples with such toxins. Here, disposable immunosensing system was designed using a selective anti-α-hemolysin antibody assembled onto nanostructured disposable sensor chips modified with AuNPs-Co₃O₄-CuO@MWCNTs nanocomposite. Bimetal oxides of cobalt and copper were chemically synthesized and integrated with the multiwalled carbon nanotubes and gold nanoparticles to yield the desired sensing platform that provides high electrocatalytic and high sensing performance. Consequently, the electrochemical assay was systematically optimized, with several analytical parameters evaluated, including the nanocomposite composition ratios, antibody loading concentration, incubation time between the exotoxin and its specific antibody, and the detectable concentration range of the target toxin. Furthermore, the nanostructured materials were comprehensively characterized through a combination of physical and chemical techniques, such as X-ray diffraction (XRD), Raman spectroscopy, electron microscopy, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). Eventually, a calibration curve with a wide dynamic range was obtained, demonstrating high sensitivity with a limit of detection of 0.01 ng/mL. The applicability of the newly designed immunosensors for real quantitative analysis in food samples was investigated, showing high recovery rates (from 96.0 to 107%) towards the target analyte.

To solve the difficult recycling and poor durability of puncture-resistant soft composites, this study proposed a synergistic reinforcement of hydrogel/aramid composites by dual nanomicelle cross-linked networks using Pluronic F127DA, TiN, and TiO₂ nanoparticles. The TiN nanoparticles, a photothermal conversion material, were introduced into the gel system as toughening particles, and then they were synergized with the micellar state of Pluronic F127DA to form the core–shell structure nanomicelles, which provide more crosslink points and form a triple physical crosslink network with TiO₂ NPs. This synergistic reinforcement had a significant effect on the mechanical properties of the gel matrix (302.27 MJ toughness), self-repair ability (100% under near-infrared light for 5 min), and the amazing improvement of the puncture resistance of the composites (276.78 N cone puncture resistance value, 241.98 N knife puncture resistance value). This study provides an important reference for the design of soft composites with both efficient self-healing properties and high puncture resistance.

Dating back to more than one century ago, the photocatalysis process has demonstrated great promise in addressing environmental problems and the energy crisis. Nevertheless, some single or binary composite materials cannot meet the requirements of large-scale implementations owing to their limited photocatalytic efficiencies. Since 2021, dual S-scheme heterojunction-based nanocomposites have been undertaken as highly efficient photoactive materials for green energy production and environmental applications in order to overcome limitations faced in traditional photocatalysts. Herein, state-of-the-art protocols designed for the synthesis of dual S-scheme heterojunctions are described. How the combined three semiconductors in dual S-scheme heterojunctions can benefit from one another to achieve high energy production and efficient oxidative removal of various pollutants is deeply explained. Photocatalytic reaction mechanisms, by paying special attention to the creation of Fermi levels (E_f) and charge carriers transfer between the three semiconductors in dual S-scheme heterojunctions, are discussed. An entire section has been dedicated to some examples of preparation and applications of double S-scheme heterojunction-based nanocomposites for several photocatalytic applications such as soluble pollutants photodegradation, bacteria disinfection, artificial photosynthesis, H₂ generation, H₂O₂ production, CO₂ reduction, and ammonia synthesis. Lastly, the current challenges of dual S-scheme heterojunctions are presented and future research directions are presented. To sum up, dual S-scheme heterojunction nanocomposites are promising photocatalytic materials in the pursuit of sustainable energy production and environmental remediation. In the future, dual S-scheme heterojunctions are highly recommended for photoreactors engineering instead of single or binary photocatalysts to drive forward photocatalysis processes for practical green energy production and environmental protection.

Due to the damage caused by ultraviolet (UV) radiations, the development of smart windows with UV-shielding capability is urgently needed to help reduce the aging of household items and protect human health. Traditional glasses exhibit inferior UV- and heat-shielding properties. Therefore, constructing alternative materials with high transparencies, low thermal conductivities, and excellent UV-blocking capabilities is significantly important to replace traditional glasses. Herein, switchable thermochromic transparent woods (TWs) are fabricated for smart windows using UV-curable polymer dispersed liquid crystal (PDLC) into modified woods for the first time. Thermochromic TW filled with PDLC (PDLC/TW) adjusts its visible light transmittance based on temperature without additional energy. Balsa PDLC/TW demonstrates a gradually increasing transmittance (from 28% at room temperature to 78% at 40 °C) at 550 nm. Moreover, balsa PDLC/TW exhibits outstanding UV-blocking performance and almost five times lower thermal conductivity (0.197 W m⁻¹ K⁻¹) than that of the glass (0.911 W m⁻¹ K⁻¹). As-prepared PDLC/TWs can effectively allow the passage of visible light and block UV light during the day, which is beneficial for indoor illumination and human health. Interestingly, at night, they become opaque, thereby protecting privacy. These findings highlight the considerable potentials of PDLC/TWs for application in next-generation energy-efficient buildings.

Estrogen is commonly found in dairy farm wastewater, garnering attention owing to its negative impacts on biological health and the environment. Herein, lanthanum ferrite perovskite oxides (LaFeO₃) with La defects were synthesized using the sol–gel and hydrothermal methods for efficient persulfate (PMS)-activated degradation of estrogen and other pollutants. Hydrothermally synthesized La_0.7FeO₃ (H0.7-LFO) was tailored to produce a large amount of O₂⁻, achieving 100% degradation of β-estradiol (β-E2) with an initial concentration of 2 mg/L within 60 min. The associated degradation rate constant was 22.03 times of that for sol–gel-synthesized La_0.7FeO₃. The considered H-0.7LFO/PMS system exhibited good degradation performance under various conditions, such as the coexistence of different ions, the involvement of humic acid substances, a wide pH range, and multiple reuses, indicating its excellent stability and reusability. When using the H-0.7LFO/PMS system for dairy farm wastewater, the β-E2 degradation capacity reached 82.16–99.25%, indicating notable potential for practical applications. Characterization analysis revealed that introducing La defects reduced the particle size and the number of abundant formed pores within H0.7-LFO. Further, electron transfer compensated for the involved La defect-induced charge imbalance, accelerating the Fe(III)–Fe(II)–Fe(III) redox cycle and enhancing pollutant degradation.

Organic–inorganic hybrid coatings offer a promising strategy to enhance photocatalytic activity by engineering surface chemistry and interfacial properties. In this work, hybrid coatings were fabricated on AZ31 magnesium alloy through a two-step process combining plasma electrolytic oxidation (PEO) and hydrothermal treatment with L-tryptophan (Trp) and tetraethyl orthosilicate (TEOS). Three different electrolytes, namely phosphate, aluminate, and silicate, were used during PEO to form MgO layers enriched with Mg₃(PO₄)₂, MgAl₂O₄, and Mg₂SiO₄, respectively. These oxide layers acted as chemically active platforms for subsequent hybrid layer formation. Among all samples, MgO-Si-LT exhibited the most favorable characteristics, notably reduced porosity (~ 4.47%) and the highest average pore diameter (~ 1.69 µm). It also showed the strongest Si signal, confirming dual silica incorporation from both the electrolyte and TEOS. In parallel, MgO-Si-LT revealed the most chemically diverse nitrogen states, suggesting stronger Trp coordination and enhanced interfacial stabilization. Photocatalytically, MgO-Si-LT significantly achieved 98.01% degradation of crystal violet (CV) under visible light within 120 min and notably retained 96.2% efficiency after five cycles. DFT calculations revealed that the Mg₂SiO₄ surface forms the strongest interaction with the Trp-TEOS complex, supporting enhanced charge transfer and photocatalytic efficiency. These results highlight the crucial role of anion-guided oxide chemistry in stabilizing hybrid layers and demonstrate a scalable strategy for designing high-performance photocatalytic surfaces.

In this study, a polyphenylene sulfide (PPS)-based composite was developed by incorporating triazine-based covalent organic frameworks (TCOFs) and glass fibers (GFs) to simultaneously address the challenges of thermal insulation and flame retardancy in high-temperature environments. The TCOF structure was engineered via an Ostwald ripening process to exhibit a highly porous, partially crystalline architecture, enabling multiscale phonon scattering and effectively hindering thermal transport. In parallel, surface-modified GFs served as a reinforcing scaffold, enhancing mechanical strength and promoting the formation of a robust char layer during combustion. The resulting hybrid composites demonstrated significantly reduced thermal conductivity, reaching as low as 0.056 W·m^–1·K^–1, and outstanding flame retardancy, consistently achieving UL-94 V-0 ratings across all formulations. Morphological analyses confirmed the development of dense, thermally stable char structures in the presence of both fillers. Mechanical testing further revealed that the dual-filler network enhanced the storage modulus and maintained tensile performance, despite the inherent brittleness introduced by the fillers. These findings underscore the synergistic effects of TCOFs and GFs in creating multifunctional PPS composites with superior thermal insulation, flame resistance, and mechanical durability, making them strong candidates for advanced thermal management applications.

Herein, we demonstrate a new design approach combining theoretical and practical frameworks in the development of biopolymer (chitosan)-based reduced graphene oxide (rGO) membranes with embedded functionalized carbon nanotubes (CNTs) via polymeric phase transformation. The crosslinked, highly porous biopolymer structure provides structural integrity to embed rGO laminates and CNTs, enabling them to have an ultra-water permeability of 9071.9 L m⁻² h⁻¹ bar⁻¹ (1000-fold higher than GO) with a rejection of up to 99% for methylene blue, methyl orange, rhodamine B, and bromocresol green dyes. Further, the selectivity increased with the curing times of membranes, which negatively affected the permeability. The SEM image processing technique elucidated that the as-prepared composite membrane showed 300% higher surface porosity and pore sphericity compared to that of the conventional GO membranes. Additionally, we conducted density functional theory (DFT) adsorption and sorption analysis to examine the impact of individual constituents on the membrane's properties. Furthermore, the structural stability of GO has been improved to overcome several problems related to microstructural instability, low surface porosity, and erosion under crossflow conditions, which limits its application in membrane fabrication. We believe this study provides a novel method for designing and developing separation membranes.