Advanced Composites and Hybrid Materials最新文献

The evolution of advanced additive manufacturing (AM) techniques, such as automatic tow placement (ATP), necessitates the development of compatible material systems with enhanced and tunable inherent properties. This study introduces a novel subclass of printable carbon nanocomposites based on a photocurable thermosetting resin, hybridized with graphene flakes (GF) and multiwalled carbon nanotubes (MWCNT). We systematically investigated the effects of varying nanoparticle content ratios separately, GF, MWCNT, and hybrid GF-MWCNT (0.1–0.5 wt%), on the neat printable resin. Our comprehensive characterization revealed that while incorporating carbon-based nanoparticles produced minimal changes in physicochemical properties and the additive manufacturing processability (average viscosity of 0.315 ± 0.017), it significantly altered the material’s thermal properties (residual mass increased monotonically with filler content, reaching up to 7.2% for 0.5 MWCNTs and 8.0% for hybrid GF-MWCNT) at 700 °C. The mechanical responses also exhibited notable changes. Specifically, under quasi-static mechanical loading, the AM process-induced nanoparticle agglomeration acted as a detrimental stress concentrator and voids, particularly degrading the properties of the single-nanoparticle composites, where the elastic modulus decreased from 2.5 ± 0.6 GPa (neat) to an average of 1.1 ± 0.12 GPa for filler contents. In contrast, the dual GF-MWCNT hybrid consistently yielded superior mechanical and thermal properties compared to its individual GF and MWCNT counterparts, achieving performance levels comparable to those of the neat resin. This exceptional performance, particularly when mitigating the negative effects observed under quasi-static loading, demonstrates the significant potential of these carbon-carbon hybrid nanocomposites for future integration with continuous carbon fiber additive manufacturing techniques, paving the way for high-performance structural composites.

Many biological materials, such as bone, are organic-inorganic composites, made from a polymeric matrix that supports biomineralization under mild conditions. These materials are usually composed of a small set of abundant components like polysaccharides, proteins, and minerals, and exhibit a remarkable combination of density normalized stiffness, toughness, and functionality. Producing bio-inspired synthetic porous composites with a similar combination of properties through energy-efficient processes still presents an unmet challenge. Some aspects of this challenge can be addressed using living bacteria that induce biomineralization. However, living bacteria limit biomedical applications, especially in vivo, require careful handling, and are costly. To address these limitations, we introduce enzyme-containing granular precursors exclusively made from naturally sourced polymers. These precursors can be cast or direct ink written into cm-sized structures before they are mineralized under benign conditions to reach CaCO₃ contents up to 92 wt% with a porosity of 56 vol%. The resulting mineralized scaffolds exhibit a compressive strength up to 4 MPa (specific: 5.2 MPa·cm³·g^− 1) and a compressive modulus of 56 MPa (specific: 72 MPa·cm³·g^− 1). Although measured in the dry state, these values fall within the range reported for human trabecular bone with similar porosities (50–90% (Morgan et al., Annu Rev Biomed Eng 20:119–43, 91; Tanoto et al., Extreme Mech Lett 73:102265, 92). The resulting biomineral-organic composites show low cytotoxicity. These findings highlight the potential of this approach to 3D print biocompatible CaCO₃-based composites under mild conditions. We envisage this formulation to open up new possibilities for tissue engineering.

The development of multimodal anti-counterfeiting materials integrating photoluminescence and photochromic functions holds great significance for dynamic anti-counterfeiting and information storage. Nevertheless, traditional single-component systems typically encounter issues such as limited luminescence efficiency and a lack of diversity in color regulation methods. In this research, multi - dimensional regulation of optical properties was accomplished by fabricating a type I heterojunction of the Ba_0.5Sr_0.5TiO₃ (BST5)/high entropy spinel (Cd_0.2Mg_0.2Cu_0.2Co_0.2Ni_0.2)Al₂O₄ ((CdM)A). Phase structure and spectroscopic characterizations demonstrated that the interfacial strain remarkably facilitated the enrichment of oxygen vacancies and actuated the reversible transformation between Ti^4⁺/Ti^3⁺ and Co^3⁺/Co^2⁺. This defect - color center synergistic effect not only remarkably enhances the fluorescence emission intensity but also imparts a reversible photochromic response to the sample. Further analysis indicates that the local lattice distortions and defects induced by the high entropy effect effectively enhance the efficiency of carrier migration and energy transfer. As a result, the composite system demonstrates stable cyclic luminescence - color change coupling properties under multi - wavelength excitations at 254, 302, and 365 nm. This research uncovers a unified mechanism characterized by type I band alignment and the synergy of oxygen vacancy (O_V)/Ti³⁺/Co²⁺, thereby furnishing a solid theoretical foundation and compelling experimental evidence for the design of novel multi-modal dynamic anti-counterfeiting materials.

Semiconductor-based room-temperature (RT) gas sensors have been extensively studied due to their low power consumption, which is critical for sustainable Internet of Things (IoT) applications. Two-dimensional (2D) semiconductors with high surface activity are emerging as promising candidates for the assembly of RT gas sensors; however, they currently suffer from shortcomings such as low sensitivity and poor stability. Herein, we synthesized ultrathin Mo-doped niobium oxyphosphate (NbOPO₄) nanosheets via a one-step hydrothermal method for RT gas sensing. The resulting sensors exhibit excellent performance toward isopropanol (IPA), including a high response (8.7 to 100 ppm IPA), wide working range (0.1–400 ppm), rapid response/recovery rates (55 s/41 s), an ultralow detection limit (6 ppb), outstanding selectivity, and excellent reproducibility (RSD < 5%). In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) reveals a new reaction pathway for RT IPA sensing, involving its oxidation to acetic acid rather than CO₂. This exceptional performance is attributed to the abundant oxygen vacancies induced by Mo doping and the material’s ultrathin layered morphology. Capitalizing on the inherently low power consumption of RT operation, we further constructed a highly miniaturized electronic nose system (11 mm×16 mm×8 mm) that integrates the MNOP sensor with energy-efficient wireless circuitry, demonstrating its practical utility in real-time environmental monitoring and personal health protection. The system exhibits ultralow power consumption (~ 16.5 µW), deterministic wireless communication, and high reliability in multi‑node deployment, positioning it as a competitive solution for next‑generation IoT-enabled gas sensing networks.

Ti-6Al-4V alloy is extensively utilized in biomedical applications such as bone implants due to its high corrosion resistance, favorable mechanical features, and biocompatibility. In this study, a short-time duplex aging treatment at different aging temperatures of 350, 450, 500, 550, 600, and 700 ^o C was conducted on solution-treated alloys. The microstructural observations revealed a bimodal structure consisting of globular α and α/β lamellae. By increasing the aging temperature, the globular α phase and lamellae experienced growth. With an increase in aging temperature, the strength values decreased while elongation increased. Also, the hardness of aged alloys increased after aging. The hardness grew as the aging temperature decreased. Similarly, the wear resistance improved as the aging temperature decreased. Additionally, the main wear mechanisms were abrasive wear, adhesive wear, and delamination. The aged alloys were less worn at lower aging temperatures, especially after the second stage of aging. Based on the result of in-vitro corrosion, the aged samples showed better corrosion resistance compared to the solution-treated one. In addition, the surfaces were less corroded after the second stage of aging compared to the first stage of aging. Also, an increase in aging temperature resulted in a greater thickness of the oxide layer and enhanced corrosion resistance. Furthermore, a better cytotoxic response of alloys was obtained after employing aging treatment. As the surface roughness and the thickness of the oxide layer increased, improved interaction between chondrocytes and alloys was observed, demonstrating its excellent potential as bone implants.

Poly(3,4-ethylenedioxythiophene) (PEDOT) and its derivatives have emerged as critical materials in modern electronic applications due to their exceptional electrical conductivity, biocompatibility, and processability. This comprehensive review examines the state-of-the-art computational strategies employed for designing and optimizing PEDOT-based electrodes across various electronic applications. We systematically assess multiscale modeling approaches, from quantum mechanical calculations to macroscopic device simulations, including Density Functional Theory (DFT), atomistic and coarse-grained Molecular Dynamics (MD), Finite Element Method (FEM), and emerging Machine Learning/Artificial Intelligence techniques. The review elucidates how these computational methods provide critical insights into PEDOT’s electronic structure, charge transport mechanisms, morphological characteristics, and interfacial behaviors. Particular emphasis is placed on structure-property relationships, including the aromatic-to-quinoid transition upon doping, the formation of polarons and bipolarons, the influence of π-π stacking on charge mobility, and the critical role of counterions in modulating electronic performance. We demonstrate their application in designing optimized electrodes for supercapacitors, organic electrochemical transistors, and flexible electronics. Finally, we analyze existing limitations in current computational frameworks and identify promising future directions, including multiscale integration, improved force fields, and quantum machine learning, that will accelerate the rational design of next-generation PEDOT-based materials with tailored functionalities.

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This review highlights the integration of computational strategies like DFT, MD, FEM, and ML/AI in designing PEDOT-based electrodes, emphasizing their role in understanding electronic structure, charge transport, morphology, and mechanical behavior. It explores recent advancements, applications, limitations, and future directions for optimizing PEDOT electrodes in electronic devices.

The selective detection of volatile organic compounds (VOCs) such as ethanol and methanol remains challenging due to their structural similarities and low reactivity, necessitating simple, real-time sensors for applications in health monitoring, environmental safety, and industrial processes. Herein, we report a graphene oxide (GO)-enhanced polymer cholesteric liquid crystal interpenetrating polymer network (PCLC_IPN) photonic array dot sensor for discriminating ethanol, methanol, and their mixtures (ratios 1:1, 1:3, 3:1) in aqueous solutions. The sensor integrates a porous PCLC template with a poly(acrylic acid)/GO (0.05 wt%) hydrogel, functionalized by 0.60M NaOH to disrupt hydrogen bonds and enable reversible swelling/deswelling. GO incorporation facilitates π-π electron stacking, enhancing alcohol absorption and structural stability. UV-vis transmission spectroscopy reveals linear photonic bandgap wavelength shifts (Δλ_PBG) from 5% to 70% alcohol concentrations, with sensitivities of -0.902 to -1.260 nm/% at 5 s for various compositions, outperforming prior systems limited to 5–60% or nonlinear responses. The distinct ethanol/methanol response is attributed to differences in their Hansen solubility parameters. The sensor exhibits rapid response, low limits of detection (LoD: -1.244 to -3.291%/15 µL), and reversibility over 80 cycles. This photonic platform advances label-free, visual VOC sensing for point-of-care and on-site applications.

It is imperative to mitigate the detrimental influences of the electromagnetic waves (EMWs) generated by the surrounding communication and digital systems. Harnessing the material characteristics along with the structural facets has been arising as an innovative solution to harvest enhanced capabilities of electromagnetic interference (EMI) shielding with elevated absorption and minimized reflection. In this work, the EMI shielding capabilities of Ti₃C₂T_x MXene-coated polymeric triply periodic minimal surface (TPMS) structures were systematically investigated. The influence of TPMS architectural parameters, such as geometry and periodicity, on EMI shielding performance in the X-band frequency range was meticulously evaluated. Additionally, the gradient-conductive TPMS structures were fabricated to achieve absorption-dominated EMI shielding. By optimizing both the structural parameters and the coating process, Ti₃C₂T_x MXene-coated TPMS lattices achieved an EMI shielding effectiveness (EMI SE) exceeding 50 dB, with more than 75% of the EMWs attenuated via absorption. This work paves the way for precise modulation of EMI shielding performance and tunable control over the underlying shielding mechanisms.