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Supercapacitors (SCs) have emerged as a promising energy-storage technology, bridging the power and energy density gap between conventional capacitors and batteries. Their high-power density, rapid charge–discharge rates, extended cycle life, and safe operation make them well-suited for next-generation energy applications. Among the materials investigated for SC electrodes, manganese oxide (MnO₂) is particularly promising due to its multiple oxidation states, high theoretical capacitance, and wide operating potential window. This review comprehensively examines recent advancements in MnO₂-based SCs, with an emphasis on MnO₂ composites incorporating carbon materials, conducting polymers (CPs), other transition metal oxides (TMOs), and metal–organic frameworks (MOFs) and covalent organic frameworks (COFs). The synergistic effects and electrochemical performance improvements achieved through these composites are discussed in depth, highlighting strategies for stabilizing MnO₂'s cycling performance and enhancing energy storage through structural integration. Additionally, we address emerging trends and future directions in MnO₂ composite design for SC applications, underscoring their transformative potential for high-performance, scalable energy storage solutions. [ABSTRACT FROM AUTHOR]

Since the initial observation of carbon nanotubes (CNTs) and graphene platelets (GPLs) in the 1990 and 2000s, the demand for high-performance structural applications and multifunctional materials has driven significant interest in composite structures reinforced with GPLs and CNTs. Incorporating these nanofillers into matrix materials markedly enhances the mechanical properties of the structures. To further improve efficiency and functionality, functionally graded (FG) distributions of CNTs and GPLs have been proposed. This study presents an extensive review of computational approaches developed to predict the global behavior of composite structural components enhanced with CNT and GPL nanofillers. The analysis focuses on key structural elements, such as plate-type configurations, cylindrical and curved shells, and beams, emphasizing the computational techniques utilized to simulate their mechanical behavior. The utilization of three-dimensional elasticity theories and equivalent single-layer (ESL) frameworks, which are widely employed in the modeling and analysis of these composites, is comprehensively discussed. Additionally, the paper examines various mechanical performance aspects, including static, buckling, post-buckling, vibrational, and dynamic responses for the mentioned structures. The unique features of hybrid nanocomposites, combining CNTs and GPLs, are also analyzed. Furthermore, the study delves into the fabrication and processing techniques of these materials, with a particular focus on strategies to mitigate nanofiller agglomeration. The review extends to cover thermal and electrical properties, durability under environmental exposure, fatigue resistance, and vibration-damping characteristics. In conclusion, the paper underscores the necessity for ongoing advancements in computational modeling to facilitate improved design, analysis, and optimization of nanocomposite structures. Future research opportunities in this rapidly advancing domain are also outlined. [ABSTRACT FROM AUTHOR]

All-polymer aqueous batteries, featuring electrodes and electrolytes made entirely from polymers, advance wearable electronics through their processing ease, inherent safety, and sustainability. Challenges persist with the instability of polymer electrode redox products in aqueous environments, which fail to achieve high performance in all-polymer aqueous batteries. Here, we report a polymer-aqueous electrolyte designed to stabilize polymer electrode redox products by modulating the solvation layers and forming a solid-electrolyte interphase. Polyaniline is selected as an example for its dual functionality as a cathode or anode working by p/n doping mechanisms. This approach pioneers the application of polyaniline as an anode and enhances the high-voltage stability of polyaniline cathode in an aqueous electrolyte. The resulting all-polymer aqueous sodium-ion battery with polyaniline as symmetric electrodes exhibits a high capacity of 139 mAh/g, energy density of 153 Wh/kg, and a retention of over 92% after 4800 cycles. Spectroscopic characterizations have elucidated the hydration structure, solid-electrolyte interphase, and dual-ion doping mechanism. Large-scale all-polymer flexible batteries are fabricated with excellent flexibility and recyclability, heralding a paradigmatic approach to sustainable, wearable energy storage. This study presents a flexible, recyclable all-polymer aqueous battery, offering a sustainable solution for wearable energy storage. The resulting all-polyaniline aqueous sodium-ion battery shows a capacity of 139 mAh/g and over 92% retention after 4800 cycles. [ABSTRACT FROM AUTHOR]

Owing to the intrinsic excellent mechanical, electrical, and thermal properties of carbon nanotubes (CNTs), carbon nanotube fibers (CNTFs) have been expected to become promising candidates for the next-generation of high-performance fibers. They have received considerable interest for cutting-edge applications, such as ultra-light electric wire, aerospace craft, military equipment, and space elevators. Wet-spinning is a broadly utilized commercial technique for high-performance fiber manufacturing. Thus, compared with array spinning from drawable CNTs vertical array and direct dry spinning from floating catalyst chemical vapor deposition (FCCVD), the wet-spinning technique is considered to be a promising strategy to realize the production of CNTFs on a large scale. In this tutorial review, we begin with a summative description of CNTFs wet-spinning process. Then, we discuss the high-concentration CNTs wet-spinning dope preparation strategies and corresponding non-covalent adsorption/charge transfer mechanisms. The filament solidification during the coagulation process is another critical procedure for determining the configurations and properties for derived CNTFs. Next, we discuss post-treatment, including continuous drafting and thermal annealing, to further optimize the CNTs orientation and compact configuration. Finally, we summarize the physical property-structure relationship to give insights for further performance promotion in order to satisfy the prerequisite for detailed application. Insights into propelling high-performance CNTFs production from lab-scale to industry-scale are proposed, in anticipation of this novel fiber having an impact on our lives in the near future. [ABSTRACT FROM AUTHOR]

Corrosion of critical metal components exacts a heavy toll in terms of maintenance and replacement costs and damage to ecosystems upon failure. Polymeric barrier coatings protect against corrosion; however, design principles for modulating polymer structure to improve corrosion inhibition remain contested and elusive. Here, we examine molecular-weight-dependent differences in the efficacy of corrosion inhibition on aluminum substrates afforded by polyetherimide (PEI) coatings. Analyses of coated substrates evidence a clear trend denoting improved corrosion inhibition for higher weighted-average molecular weight (MW) PEI. The more rigid and entangled macromolecular network of higher-MW variants exhibit stable impedance values, |Z|0.01 Hz ca. 1010 Ω/cm2, upon extended immersion in brine media, whereas lower-MW variants are readily hydrated and disentangled resulting in a significant reduction in impedance values. Results illuminate mechanistic understanding of molecular-weight-dependence in corrosion inhibition, advance a framework for considering the dynamical evolution of secondary structure, and exemplify generalizable design principles for corrosion inhibition. [ABSTRACT FROM AUTHOR]

This study investigates the dynamic energy absorption performance of composite sandwich panels with two different configurations of lattice truss core. Two types of core structures were designed and created using polyamide 12 through the selective laser sintering (SLS) additive manufacturing method. These structures, with uniform and graded cell topologies, were created by changing the geometry and layer density of the body-centered cubic (BCC) unit cell. The cores were used to fabricate composite sandwich panels, which were made with E-glass/epoxy face sheets. Then, their ability to absorb energy during low-velocity impact and quasi-static compressive strength was tested using both experimental and numerical methods. It was found that the graded structure absorbed 10, 5, and 3% more energy than the uniform structure for the energy levels of 12.4, 16.5, and 17.9 J, respectively. It was also found that both structures could absorb at least 90% of the impact energy. In terms of strength, the uniform structure was able to tolerate 1.15 times larger impact loads, indicating its higher strength than the graded structure. The uniform structure had 8% more compressive strength. [ABSTRACT FROM AUTHOR]

High voltage AC/DC cables require thicker insulation to ensure excellent insulation performance. Selecting the appropriate crosslinker to design the crosslink and crystalline structure of XLPE is key to the insulating properties. Although the crystallinity of XLPE has been extensively studied by using X-ray diffraction and differential scanning calorimeters, few researchers have designed in situ experiments to observe its structure. In this paper, we have created an in situ observational experiment to monitor the structural changes of XLPE insulation. XLPE formed by DTAP crosslinker produces lower gas byproducts, which can effectively reduce the degassing time and energy consumption. The test results and COMSOL simulations indicate that the XLPE formed by straight-chain alkane crosslinkers has better mechanical, thermal and electrical insulating properties than cyclic alkane crosslinkers. Our work is of great significance for selecting suitable crosslinker to control the structure of XLPE and determining the production conditions for high-voltage cables. [ABSTRACT FROM AUTHOR]

Wearable strain sensors have attracted research interest owing to their potential within digital healthcare, offering smarter tracking, efficient diagnostics, and lower costs. Unlike rigid sensors, fiber‐based ones compete with their flexibility, durability, adaptability to body structures as well as eco‐friendliness to environment. Here, the sustainable fiber‐based wearable strain sensors for digital health are reviewed, and material, fabrication, and practical healthcare aspects are explored. Typical strain sensors predicated on various sensing modalities, be it resistive, capacitive, piezoelectric, or triboelectric, are explained and analyzed according to their strengths and weaknesses toward fabrication and applications. The applications in digital healthcare spanning from body area sensing networks, intelligent health management, and medical rehabilitation to multifunctional healthcare systems are also evaluated. Moreover, to create a more complete digital health network, wired and wireless methods of data collection and examples of machine learning are elaborated in detail. Finally, the prevailing challenges and prospective insights into the advancement of novel fibers, enhancement of sensing precision and wearability, and the establishment of seamlessly integrated systems are critically summarized and offered. This endeavor not only encapsulates the present landscape but also lays the foundation for future breakthroughs in fiber‐based wearable strain sensor technology within the domain of digital health. [ABSTRACT FROM AUTHOR]

Liquid crystalline polymer (LCP) solutions undergo uniaxial elongation in fiber spinning, yielding highly oriented fibril-structured fibers with enhanced orientation and mechanical properties. This study explores how initial fiber orientation and Frank elasticity influence the dynamics and stability of the isothermal spinning process for LCP solutions. The simplified Larson-Doi mesoscopic model is employed, capable of capturing elastic stress emerging from domain structure evolution. Two main factors, inlet orientation and the Ericksen number as a parameter representing Frank elasticity, significantly affect steady-state fiber orientation profiles and the onset of draw resonance instability, as determined through linear stability analysis. The sensitivity of spinline flow to a sinusoidal disturbance is assessed using the frequency response method. Changes in stability onset concerning these two main factors are reasonably correlated with the extensional behavior of the LCP solution in the spinline and the results of the frequency response. [ABSTRACT FROM AUTHOR]

The utilization of carbon nanotubes (CNTs) in the field of cancer therapeutics has emerged as a promising avenue of research in recent years. This inquiry delves into the multifaceted potential of bio-functionalized carbon nanotubes for diverse anti-cancer activities. Carbon nanotubes, with their distinct structural and physicochemical properties, offer a versatile platform for innovative approaches in cancer diagnosis, treatment, and comprehension of the underlying molecular mechanisms. The process of bio-functionalizing CNTs plays a pivotal role in enhancing their compatibility with living organisms and specificity, thereby facilitating precise targeting of cancer cells. This scholarly article elucidates the strategies employed for modifying the surface of CNTs and characterizes the bio-functionalized CNTs, setting the stage for their application in anti-cancer therapies. Through a thorough examination of the anti-cancer activities, this research investigates the potential of CNTs to serve as carriers for drug delivery, exemplifying their ability to enhance the availability of drugs and mitigate side effects. Moreover, this study elucidates the diagnostic potential of bio-functionalized CNTs, explicating their applications in cancer imaging, detection, and identification of biomarkers. Mechanistically, the article unveils the pathways through which these nanotubes exert their anti-cancer effects, including the induction of apoptosis and modulation of autophagy. While acknowledging the immense promise of bio-functionalized CNTs, this research also highlights the existing challenges and limitations. Looking toward the future, this article discusses emerging trends in CNT-based cancer therapies, envisioning a future where personalized medicine and nanotechnology converge to revolutionize cancer treatment. Ethical and regulatory considerations are also deliberated upon, emphasizing the need for a responsible and safe transition of these technologies from laboratory experiments to clinical applications. In summary, this study unravels the burgeoning potential of bio-functionalized carbon nanotubes in various anti-cancer activities, underscoring their transformative impact on cancer research and therapy. As the field of nanomedicine continues to expand, these findings contribute to a deeper understanding of the possibilities that lie ahead in the battle against cancer. [ABSTRACT FROM AUTHOR]

Biosynthetic route for the synthesis of nanoparticles involving fossil extract is a modest eco-friendly process; the study focused on a relatively new class of functional materials known as polymerised ionic liquids. The synthesised nanoparticles were then characterised through FTIR and X-ray diffraction spectroscopy. Nanoparticles incorporated in polymers provide an exciting base for newer technology for the development of cost-effective electrochemical devices. Polyvinyl formal (PVFM) is one of the eco-friendly semi-crystalline polymers which has inter- and intra-molecular hydrogen bonds, whose degree is greatly dependent on the texture of the polymer. We have fabricated a naturally plasticized nanopolymer electrolyte membrane with high ionic conductivity using nano MMT incorporated in PVFM. Randomly interwoven nano-fibrous structures are generally preferred for electrolyte systems due to their continuous structure. The use of nano-composites provided a better polymer interface as well as the high free volume size, through which molecule transport occurs in nano-composite membrane matrix. The advantage of a surface comprised of ultra-fine, continuous nano fibres is that it naturally becomes highly porous. Nano-composite membrane due to its high porosity becomes a major responsive factor to enhance the ionic conductivity. We have considered a comparative study of these fabricated nano-composites. The structural behaviour of the polymer nano-composite membrane is investigated by XRD and FTIR. XRD curve revealed the amorphous nature of the membrane. It is favourable for better conduction and sensing behaviour, as the conductivity–frequency plots showed the Universal power law. The asymmetric shape of the Dielectric relaxation plots gave a strong evidence of low-frequency dispersion and deviation from the pure Debye behaviour. [ABSTRACT FROM AUTHOR]

Electro-optical effect-based liquid crystal devices have been extensively used in optical modulation techniques, in which the Kerr coefficient reflects the sensitivity of the liquid crystals and determines the strength of the device's operational electric field. The Peterlin–Stuart theory and the O'Konski model jointly indicate that a giant Kerr coefficient could be obtained in a material with both a large geometrical anisotropy and an intrinsic polarization, but such a material is not yet reported. Here we reveal a ferroelectric effect in a monolayer two-dimensional mineral vermiculite. A large geometrical anisotropy factor and a large inherent electric dipole together raise the record value of Kerr coefficient by an order of magnitude, till 3.0 × 10−4 m V−2. This finding enables an ultra-low operational electric field of 102–104 V m−1 and the fabrication of electro-optical devices with an inch-level electrode separation, which has not previously been practical. Because of its high ultraviolet stability (decay <1% under ultraviolet exposure for 1000 hours), large-scale production, and energy efficiency, prototypical displayable billboards have been fabricated for outdoor interactive scenes. This work provides new insights for both liquid crystal optics and two-dimensional ferroelectrics. [ABSTRACT FROM AUTHOR]

Foams exhibit a low-density characteristic and possess a notable level of structural rigidity. Consequently, they are frequently observed in natural formations such as wood and bones. However, in modern society, foams are predominantly employed for functional purposes rather than structural ones. Moreover, there has been significant progress in the development of structural–functional integrated applications that extensively utilize foam materials. Foams find numerous applications in different fields, major of these including metal foams for lightweight construction, crash energy absorption, thermal insulation, and acoustic management; ceramic foams for thermal management systems and high-temperature appliances; polymer foams in packaging, and cushioning. The selection of materials for the aforementioned applications is mostly based on structure–property correlations. Due to the inherent complexity and time-consuming nature of material tests and characterization in predicting the topology of foam microstructures, a potential avenue for foam material design lies in the theoretical or analytical prediction of microstructural topology. The main objective of this study is to investigate the structure–property correlation of foams, different structural models, computational algorithms, and non-destructive technologies. However, the overall design of the foam microstructure was achieved through the utilization of two reengineering approaches, namely forward engineering and reverse engineering. All the models that have been designed are thoroughly examined in terms of their advantages and disadvantages. Additionally, we discuss thoroughly the requirement for economical, streamlined, and effective technology in order to establish the structure–property correlations of foams, to achieve a 3D realistic microstructure. [ABSTRACT FROM AUTHOR]

The effect of the gradually formed cross-linked structure on the thermal properties and swelling behaviour of modified poly(vinyl alcohol) was investigated. To this aim, the semi-crystalline polymer was functionalized with aldehyde and amino moieties to produce polymers with dynamic imine cross-links, and, thus, with self-healing or curing ability. With increasing degree of functionalization (0.89–7.12%), denser polymer networks cross-linked by dynamic imine bonds were formed, the samples systematically developed thermoset-like properties compared to the pristine, initially thermoplastic PVA. As a result, the introduction of new moieties into the initial PVA lowered the glass transition (from 65.3 to 35.0 °C) and melting temperatures (from 194 to 161 °C), however, a new peak (Tcrd) with growing enthalpy values appeared on the DSC curves, which indicates that more and more energy must be supplied in order to break the imine cross-links formed between the introduced aldehyde and amino groups. The significant impact of the degree of functionalization and cross-linking density on the polymer structure was also clearly demonstrated: the crystallinity decreased as the abundance of the introduced moieties increased and the formation of cross-links proceeded. At the same time, the water desorption enthalpies of the samples increased, suggesting a stronger, chemically cross-linked thermoset-like polymer network compared to the thermoplastic poly(vinyl alcohol). [ABSTRACT FROM AUTHOR]

We performed molecular dynamics simulations of carbon nanotube (CNT) to elucidate the growth process in the floating catalyst chemical vapor deposition method (FCCVD). FCCVD has two features: a nanometer-sized cementite (Fe 3 C) particle whose melting point is depressed because of the larger surface-to-volume ratio and tensile strain between the growing CNT and the catalyst. The simulations, including these effects, demonstrated that the number of 6-membered rings of the (6,4) chiral CNT constantly increased at a speed of 1 mm / s at 1273 K , whereas those of the armchair and zigzag CNTs were stopped in the simulations and only reached half of the numbers for chiral CNT. Both the temperature and CNT chirality significantly affected CNT growth under tensile strain. [ABSTRACT FROM AUTHOR]

EIT was found recently that it can also be applied to dielectrics under a high-frequency AC voltage. However, the EIT evaluation method for dielectrics has not been established sufficiently; in particular, there are no example studies of the drawing of impedance plane diagrams, which is widely used as an evaluation method for eddy current testing (ECT). Therefore, we have attempted to draw an impedance plane diagram based on the Ampère-Maxwell equation and a simple electrical circuit, as performed in ECT. First, a theoretical solution for the impedance based on the Ampère-Maxwell equation that considers eddy and displacement currents was derived, and impedance plane diagrams were then drawn. From the impedance plane diagrams obtained, it was shown that the same trends can be drawn for the diagrams for both conductors and dielectrics. Next, an electrical circuit model for EIT was proposed that takes into account both the conductivity and the permittivity. Using this model, impedance plane diagrams for conductors and dielectrics were drawn, and for dielectrics in particular, it was shown that the diagrams can be drawn by considering the conductivity. In addition, similar to the impedance plane diagrams drawn from the electrical circuit model and derived from the Ampère-Maxwell equation, the change behavior in the diagrams clearly differs between the cases where the conductivity and permittivity change and the case where the lift-off changes. This demonstrates the effectiveness of the electrical circuit model in providing a qualitative understanding of the effects of the dielectric conditions and measurement conditions on EIT. [ABSTRACT FROM AUTHOR]

The recent progress on the liquid crystalline (LC) dispersion of two‐dimensional (2D) transition metal carbides (MXenes) has propelled this unique nanomaterial into a realm of high‐performance architectures, such as films and fibers. Additionally, compared to architectures made from typical non‐LC dispersions, those derived from LC MXene possess tunable ion transport routes and enhanced conductivity and physical properties, demonstrating great potential for a wide range of applications, such as electronic displays, smart glasses, and thermal camouflage devices. This review provides an overview of the progress achieved in the production and processing of LC MXenes, including critical discussions on satisfying the required conditions for LC formation. It also highlights how acquiring LC MXenes has broadened the current solution‐based manufacturing paradigm of MXene‐based architectures, resulting in unprecedented performances in their conventional applications (e.g., energy storage and strain sensing) and in their emerging uses (e.g., tribology). Opportunities for innovation and foreseen challenges are also discussed, offering future research directions on how to further benefit from the exciting potential of LC MXenes with the aim of promoting their widespread use in designing and manufacturing advanced materials and applications. [ABSTRACT FROM AUTHOR]

Biobased composite films have been prepared by solvent cast and hot press methods using saturated aliphatic polyester (expressed as HP1) with different loading (i.e., 1 and 3 wt %) of CNF, citrus fiber, and dextrin. HP1 was prepared by acyclic diene metathesis (ADMET) polymerization of biobased α,ω-dienes of bis(undec-10-enoate) with isosorbide (M1) using a RuCl2(IMesH2)(CH-2–OiPr–C6H4) (HG2, IMesH2 = 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene) catalyst and subsequent tandem hydrogenation (H2 2.0 MPa, 50 °C, 12 h). The appearance (morphology, transmittance, haze), the thermal properties (including degree of crystallinity by DSC thermograms), and the tensile properties of the fabricated films were evaluated to explore effect of the additives. The prepared composite films by solvent cast and hot press methods were transparent and showed enhancement of tensile strength. The citrus fiber, upcycled product made from the waste residue of squeezed citrus juice and oil, among the other additives showed the highest tensile strength and toughness values irrespective of the molecular weight of the employed polyester or the used fabrication method. [ABSTRACT FROM AUTHOR]

Mutations in rhodopsin can cause it to misfold and lead to retinal degeneration. A distinguishing feature of these mutants in vitro is that they mislocalize and aggregate. It is unclear whether or not these features contribute to retinal degeneration observed in vivo. The effect of P23H and G188R misfolding mutations were examined in a heterologous expression system and knockin mouse models, including a mouse model generated here expressing the G188R rhodopsin mutant. In vitro characterizations demonstrate that both mutants aggregate, with the G188R mutant exhibiting a more severe aggregation profile compared to the P23H mutant. The potential for rhodopsin mutants to aggregate in vivo was assessed by PROTEOSTAT, a dye that labels aggregated proteins. Both mutants mislocalize in photoreceptor cells and PROTEOSTAT staining was detected surrounding the nuclei of photoreceptor cells. The G188R mutant promotes a more severe retinal degeneration phenotype and greater PROTEOSTAT staining compared to that promoted by the P23H mutant. Here, we show that the level of PROTEOSTAT positive cells mirrors the progression and level of photoreceptor cell death, which suggests a potential role for rhodopsin aggregation in retinal degeneration. Mutations in rhodopsin can cause the receptor to aggregate, however, it is unclear whether this molecular defect underlies the retinal degeneration in autosomal dominant retinitis pigmentosa. Here, the authors show the potential for rhodopsin aggregates to play a role in retinal degeneration. [ABSTRACT FROM AUTHOR]

The crystallinity of polyethylene has been extensively studied, but in situ experiments designed to investigate the crystallization of PE and XLPE have hardly been discussed. In this work, the crystallization behavior of PE and XLPE was investigated by designing in situ crystallization observation experiments. We have compared the crystallinity, crosslinking, viscosity properties, and gas byproducts of different XLPE insulating materials. COMSOL simulations demonstrate that the DTAP and DTBP crosslinker initiated crosslinks have better insulating properties and cable stability than the DTBC and DTBTMC crosslinkers. The formation of an insulation layer initiated by the DTAP crosslinker is beneficial for improving the breakdown strength, processing performance, and stable operation of cables. Our work is of great significance for understanding the crystallinity of XLPE and determining the correct crosslinker. Highlights: In situ crystallization observation of PE and XLPE.Simulation of ultra‐high voltage cables.Finite element analysis.Investigation of gas byproducts in XLPE. [ABSTRACT FROM AUTHOR]

Food packaging film is being developed using biodegradable polymers to prolong the shelf life of foods and address the environmental damage caused by non‐biodegradable plastics. Poly(vinyl alcohol) (PVA) is a biodegradable polymer with outstanding characteristics and can be easily shaped into a film. However, PVA‐based film still faces several obstacles that seriously restrict its practical application in the food packaging industry, particularly its low thermal stability limits the film process method. The growing preference demand for PVA‐based films with enhanced thermal stability in food packaging can be attributed to their advantageous characteristics, including commendable temperature resistance, safety, versatile processing capabilities, and prolonged shelf life. It is critical to comprehend the difficulties with PVA thermal degradation behavior and mechanism, and how to address this problem. In this review, we provide strategies for improving the thermal stability of PVA film including modification with environmentally friendly polymers, nanoparticles, and crosslinking agents. Also, the current challenges, and the potential for future advancements in the thermal stability of PVA and its composites are proposed. The new insight into the relationship between PVA based film processing and thermal properties of materials are expected to provide a valuable guide for developing PVA films with high thermal stability. [ABSTRACT FROM AUTHOR]

Remelting and remolding characteristics of thermoplastic resin make the carbon fiber-reinforced polyether-ether-ketone (CF/PEEK) composite process unique recyclability and reusability, while thermal characteristics play the crucial mechanism. This paper presents a comprehensive investigation on thermal characteristics of CF/PEEK drilling in terms of the heat transfer mechanism, crystallinity, and hole making performance. Crystallinity is introduced to quantitatively evaluate the change of material performance for CF/PEEK drilling where the crystallinity is positively correlated with tensile strength. Parameter analysis shows that the increased spindle speed leads to the increase of drilling temperature, crystallinity, and slightly deduces the tensile strength of CF/PEEK. The heat transfer curve of CF/PEEK drilling was first obtained and it is found that the heat transfer experiences three stages, namely steady rising, slow falling, and fast falling stage. Crystallinity comparative analysis between the hole wall and chips reveal that heat transfer effect dramatically affects the crystallinity when the drilling temperature exceeds the glass transition temperature (142 °C). Further, high temperature-induced PEEK smearing effect reduces the fiber exposure and surface roughness of hole wall but increases the crack appearance. The work provides important guidance for the high quality drilling of CF/PEEK composites from the point of view of the thermal characteristics. [ABSTRACT FROM AUTHOR]

The three-dimensional (3D) porous carbon materials are helpful for forming thin, light-weight, wide effective absorption bandwidth and strong absorption intensity absorbers. However, previous methods were not environmentally friendly enough. Thus, in this work, the Fe/Fe3C@porous carbon was synthesized from soluble starch and Fe(NO3)3·9H2O via chemical bowling and subsequent carbonization at 700 °C with different ratios. When the ratio of starch to Fe(NO3)3·9H2O is 1:1.5, the porous carbon exhibits a strong absorption ability with minimum reflection loss (RLmin) value of −16.64 dB at 16.78 GHz, when the thickness is 1.75 mm and the proportion of paraffin wax is 30 wt%. The synergy of well impedance matching, sufficient loss performance, and interface polarization makes 3D porous carbon materials an excellent wave absorber. This work provides a good inspiration for studying outstanding performance microwave absorption materials. [ABSTRACT FROM AUTHOR]

Amidst the progressive depletion of non-renewable resources on a global scale, the expedited development of green and sustainable materials has become an imperative. Cellulose, a recognized environmentally friendly substance, presents itself as a solution owing to its low cost, abundant availability, facile degradability, and renewability. Its potential to gradually supplant petroleum resources, thereby yielding a diverse array of high value-added materials, is well acknowledged. Herein, we present an exploration of the utilization of cellulose as a precursor, rooted in its fundamental properties. Moreover, we undertake a comprehensive review of the preparation techniques and structural property characteristics exhibited by mainstream cellulose-based functional materials. These materials notably include cellulose spheres, cellulose hydrogels, cellulose aerogels, cellulose films, and cellulose-derived carbon materials. Following this extensive review, our article accentuates the strides made in the field of cellulose-based functional materials across diverse pertinent domains. These encompass materials essential for adsorption and separation purposes, biomedical devices, electrode capacitive applications, and the emerging landscape of smart electronic devices. Concluding our discourse, we address the challenges that lie ahead and outline the potential future prospects for the development of cellulose-based functional materials. [ABSTRACT FROM AUTHOR]

This research focuses on evaluating the combined effects of the interphase of the three-phase magneto-electro-elastic (TPMEE) composites and carbon nanotubes (CNTs) agglomeration on the nonlinear deflection of the multifunctional sandwich plate, using an artificial neural network (ANN) assisted finite-element (FE) approach. The data points collected from the in-house developed FE computational tool are used to train the ANN model. To this end, a backpropagation-based Levenberg–Marquardt algorithm is used. The core of the plate is made of agglomerated CNTs, and the facesheets are made of TPMEE composites. Two different agglomeration states, partial and complete, are considered for evaluation. Also, three variations of CNTs arrangement are assumed. On the other hand, the interphase effects are incorporated through its volume fractions and compositions. The plate kinematics is based on the higher-order shear deformation theory, and the nonlinearity is assumed to follow von Karman's strain-displacement relation. The equations of motion are derived using the total potential energy principle. Finally, the direct iterative method is used to arrive at the solutions. The numerical examples are also provided to understand the influence of coupling fields associated with the parameters, such as agglomeration, interphase volume fraction, interphase compositions and CNTs arrangement. [ABSTRACT FROM AUTHOR]

Aiming to green machining of single crystal sapphire, polysaccharide-bonded soft abrasive tool using hydrothermal gelatinisation method was proposed. Mechanical properties of prepared polysaccharide films show that when the weight ratio of natural polysaccharide to cross-linked polysaccharide is 1:1, the tensile strength and extension rate of the film are relatively optimal. Composition and making process of polysaccharide bonded abrasive tool was built. Samples of polysaccharide bonded soft abrasive tools were made by which the single crystal sapphire substrates were machined. It is found that by adopting guar gum as dispersion agent and hydrothermal gelatinisation, the abrasive sedimentation during making process of abrasive tool is substantially eliminated, and better abrasive holding ability is attained. XPS and Raman microscope analysis showed that material of single crystal sapphire was removed by mechano-chemical reaction with good surface integrity. Abrasive tools with abrasive to binder ratio of 4:1 presented relatively better self-sharpening and machining performance, and the material removal rate reached 0.427 μm/min. More interesting, XPS and FT-IR analyses both indicated that the polysaccharide binder dehydrated by the friction heat during machining process. [ABSTRACT FROM AUTHOR]

Liquid crystal polymer (LCP) is the preferred material for 5G antenna materials, but its poor film processing performance has become the main factor restricting its development. In this paper, polyetherimide (PEI) was blended with LCP, and LCP/PEI composite films were prepared by interleaved extension blow molding equipment. The effects of PEI content and interleaved extension blow molding equipment on the stability of the film bubble and the properties of the product were studied. The results show that the addition of PEI can effectively improve the stability of the film bubble in the process of interleaved extension blow molding, and the toughness of the prepared LCP/PEI composite film is obviously improved. In addition, the addition of PEI does not affect the low dielectric properties of LCP, which perfectly matches the low dielectric characteristics required for 5G communication. [ABSTRACT FROM AUTHOR]

In this work, graphene was synthesized by electrochemical exfoliation in a non-aqueous medium. For the first time, 2-methoxyethanol is used as an exfoliation reagent. Electrochemical exfoliation is a promising method to produce graphene because it is scalable, environmentally friendly, and relatively inexpensive. In this work, we have shown how graphene can be gently exfoliated at high concentrations in low boiling point solvents. There are several organic solvents that can be used for exfoliating graphene, including NMP, DMF, DMSO, DMAC, GBL, and others. However, they all have high boiling points that make it difficult to remove them from the graphene dispersion. This is important because solvent residues can contaminate graphene and affect its properties. Low boiling point solvents (2-methoxyethanol) are well suited for exfoliating graphene because they can easily penetrate the graphite layers and disrupt the strong van der Waals forces that hold them together. The graphene sheets were studied by XRD, FESEM, HRTEM, AFM, XPS, and Raman spectroscopy. The thinnest graphene sheets detected by AFM were 2.3 nm, which can be considered as few layered graphene, and according to XPS measurement, EG has a C/O ratio of 16.8%, which is higher than that of electrochemical exfoliation in aqueous medium and microwave-assisted graphene fabrication. [ABSTRACT FROM AUTHOR]

Poly(vinyl alcohol) (PVA) is used in various fields as a degradable polymer with excellent physical properties. However, poor thermal processability impedes its development. Herein, cellulose nanofibers (CNFs) are added to the PVA matrix to form strong hydrogen bonding with molecular chains and achieve melt-processing of PVA under the synergy of plasticizers. Specifically, a facile but efficient mechanical exfoliation method with the aid of organic stone waste (OSW) is designed to realize scalable manufacturing of CNFs. As an industrial by-product, OSW has abundant oxygen-containing groups on the surface, which can interact with cellulose and enhance the shear and friction force of cellulose during the mechanical exfoliation process. The resulting CNFs with an average diameter of 33.85 nm can significantly expand the melt-processing window of PVA to 66.6 °C, and benefiting from the nucleation effect of CNFs, the grain size of the composite material is refined. The tensile strength of resulting composites is significantly improved by 72.5% with the incorporation of 10 wt% CNFs. This strategy not only opens up scalable manufacturing of CNFs but also provides a new path for PVA melt-processing. [ABSTRACT FROM AUTHOR]

Carbon nanofibers (CNFs) were heat-treated at 1100 °C (CNF1100) and 2500 °C (CNF2500), respectively, and embedded as fillers at different mass percentages into an epoxy mixture. The paper aims at evaluating, through a comparison between the two different types of resulting nanocomposites, the influence of the CNF heat treatment on the thermal, mechanical, and electrical performance of the formulated samples. Thermogravimetric analysis (TGA) showed oxidative stability in the air of CNF2500 approximately 200 °C higher than the CNF1100 ones. The first oxidation stage of the resins embedding the two typologies of CNFs falls between 380 and 480 °C. This means that the temperature of the heat treatment of the nanofiller does not influence the temperature at which the thermodegradation of the nanocomposites starts. Differential Scanning Calorimetry (DSC) data show that the highest degree of cure (DC) was recorded for the epoxy samples filled with CNF2500. CNF thermal treatment increases the direct current (dc) conductivity of the nanocomposite by 3 orders of magnitude around the electrical percolation threshold (EPT) and increases the storage modulus of the CNF2500-based resins up to 60 °C compared with the unfilled resin. The peculiar wall structure of CNF1100 determines a further slight enhancement. Tunneling Atomic Force Microscopy (TUNA) reveals that the CNFs are evenly distributed on the nanodomains showing higher electric current values for samples loaded with CNF2500. [ABSTRACT FROM AUTHOR]

The development of conductive and porous interlayer can effectively mitigate the shutting of lithium polysulfide (LiPSs) for high efficiency lithium-sulfur batteries (LSBs). Ultra-thin and lightweight multifunctional 3D multilayer cross-linked carbon nanofiber-carbon nanotube (CNFs-CNTs) interlayers were developed by growing CNTs vertical to CNFs to effectively trap LiPSs. The CNF-CNT films have excellent electrical conductivity and excellent mechanical properties, providing a homogeneous conductive network and a physical barrier to LiPSs for LSBs. The battery with CNF-CNT interlayer provided an initial discharge capacity of 1296.7 mAh g−1 at 0.2 C magnification and a discharge specific capacity of 864.7 mAh g−1 after 100 cycles with a high-capacity retention rate (66.68%). In addition, the discharge specific capacity of 699.2 mAh g−1 is still maintained after 500 cycles at 1C. The coulomb efficiency basically stays above 95% and possesses a very high cycling stability. This work provides an effective strategy for the application of functional interlayer in LSBs, which can suppress the shuttle effect and lithium dendrite. [ABSTRACT FROM AUTHOR]

An attempt has been made to tune the DC electrical conductivity and impedance characteristics of the nanocomposites by coating carbon nanotubes (CNTs). A microwave‐assisted in‐situ polymerization approach is utilized to coat the CNTs with polystyrene and no initiators are used. The nanocomposites are characterized by FE‐SEM, TEM, FT‐IR, Raman and TGA. Based on the morphological studies, a polystyrene layer is detected on the CNTs. According to the TGA results, the weight loss in the temperature range of polystyrene decomposition increases with increasing microwave irradiation time, suggesting a higher polystyrene content. Moreover, the DC electrical conductivity of the nanocomposites, as well as the real and imaginary impedance and dielectric permittivity are explored. It is shown that increasing the irradiation time decreases the DC electrical conductivity and dielectric permittivity but increases the real and imaginary impedance. Since the thickness of the polystyrene layer depends on the duration of microwave irradiation, our method can be used to tune the electrical conductivity and impedance characteristics. This can be applied to practical situations where a particular resistance is required. [ABSTRACT FROM AUTHOR]

Driven by the quest for greener and more sustainable materials, the presented review analyzes recent studies in which wood and wood-based materials were combined with carbon nanomaterials in the form of carbon nanotubes and graphene. The analysis shows a close kinship between these two carbon-based materials. The first studies have shown that wood may be directly transformed into sp2-bonded carbons, i.e., form graphene-like structures. Further, it has been demonstrated that both carbon nanotubes and graphene can be used to coat or infiltrate wood and processed wood-based materials such as flexible wood sponges or biochars. Thanks to the unique electrical, mechanical, thermal, and wetting properties of graphene and carbon nanotubes, their wood-based nanocomposites were shown to have many potential applications in green electronics area or as nanodevices. Finally, a new range of studies in the area of wood composites showed that carbon nanomaterials integrated into wood-based boards could improve the properties of the former ones. The presented review shows that this emerging area of research on wood-based materials, graphene, and carbon nanotubes is highly promising and interesting in the context of new applications and future perspectives for sustainable development. [ABSTRACT FROM AUTHOR]

Casting and solid-state reaction methods were used to prepare composites of PVA/CMC/PEG/x wt% Zn0.9Cu0.1S (x = 0, 1, 3, 5, 10). The nanofiller Zn0.9Cu0.1S was investigated applying XRD Rietveld analysis. XRD, FTIR, SEM, and EDS techniques were used to trace the variation of the structure and morphology of the PVA/CMC/PEG blend upon loading with different Zn0.9Cu0.1S contents. The effect of the filler content (x) on the linear and nonlinear features of the host blend was examined. The direct and indirect optical band gaps of PVA/CMC/PEG (5.87 and 5.31 eV) reduced upon loading with Zn0.9Cu0.1S, attaining minimum values (4.47 and 3.65 eV) for x = 10%. The fluorescence intensity and the emitted colors of the blends depended on the amount of the nanofiller. The dielectric constant (ε′), dielectric loss factor (ε′′), the real (M′) and imaginary (M′′) parts of the electric modulus changed nonmonotonically with the nanofiller content (x). Among all blends, ε′ disclosed higher values for the blend with x = 10 wt% and lowest ones for x = 1 wt%, while ε′′ attained highest values for the blend with x = 3 wt%, and lowest values for x = 5 wt%. [ABSTRACT FROM AUTHOR]

The binary polymer nanocomposite (PTh/nNiO) was synthesised by chemical oxidation polymerisation followed by mechanical mixing. The ternary polymer nanocomposites (PTh/cMWCNT/nNiO) were synthesised through a interface in-situ chemical oxidation polymerisation method. The synthesised samples were characterised by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), and cyclic voltammetry (CV) measurements to analyse the structure, morphology, elemental composition, and electrochemical performance, respectively. Specific capacitance values obtained for PTh/nNiO and PTh/cMWCNT/nNiO composites are 365 F g−1 and 419 F g−1, respectively, and the ternary composite may be a promising candidate for supercapacitor application. [ABSTRACT FROM AUTHOR]

Manipulating nanostructure assemblies is important in using them as structural and functional materials. Carbon nanotubes (CNTs) lack the ability to reconstruct their entangled network. In this work, we report a strategy with which to realize efficient manipulation of CNT networks by forming double networks with branched polyethylenimine (PEI). The double network was highly viscoelastic and ductile and enabled efficient film stretching or creeping for CNT alignment, which dramatically improved the mechanical strength of the CNT films. Due to the viscous drag from the polymer network, the CNTs showed enhanced movability in reconstructing new networks, which made the film repairable. The repairability resulted from the branched polymeric structure. This double-networking strategy provides a new way to manipulate CNT assemblies for high-performance applications. In this work, we report a strategy with which to realize efficient manipulation of CNT networks by forming double networks with branched polyethylenimine (PEI). The double network was highly viscoelastic and ductile and enabled efficient film stretching or creeping for CNT alignment, which dramatically improved the mechanical strengths of the CNT films. Due to viscous drag from the polymer network, the CNTs showed enhanced movability in reconstructing new networks, which made the film repairable. The repairability resulted from the branched polymeric structure. This double-networking strategy provides a new way to manipulate CNT assemblies for high-performance applications. [ABSTRACT FROM AUTHOR]

Carbonized fibers with quantifiable mechanical properties were prepared from environmentally benign lyocell fibers (LFs) through sulfuric acid-catalyzed continuous thermostabilization and following carbonization. The pristine LF was decomposed into small molecules which can be evaporated at high temperatures during thermal treatment, leading to a low mass yield (~ 12 wt%) after carbonization. In contrast, the impregnated LF with sulfuric acid (ILF) underwent various chemical reactions at low temperatures, catalyzed in the presence of protons and water within the fiber. These catalyzed reactions encompassed not only thermal dissociation of glycosidic bonds, but also elimination reactions, the dehydration of decomposed products to 5-hydroxymethylfurfural, and its subsequent conversion. A series of chemical analyses revealed that linear cellulosic macromolecular chains were transformed into highly crosslinked network structures consisting of decomposed products. As a consequence of this chemical transformation, the mass yield of ILF increased by more than double compared to that of LF. In addition, the density of the carbonized ILF was higher than that of the carbonized LF, indicating that impregnation with sulfuric acid contributed to the development of carbon structures. Unlike the highly brittle carbonized LFs, the carbonized fibers derived from the thermostabilized ILFs exhibited superior tensile strength and modulus with values of 0.92 GPa and 41 GPa, respectively. [ABSTRACT FROM AUTHOR]

The employment of cost-effective and durable structures is essential for the successful commercialization of perovskite solar cells (PSCs). Identifying a viable substitute for hole-selective materials (HSMs), which represent a significant expense in the production of PSCs, could provide a number of benefits. Carbon nanotube-based PSCs have shown promising potential as an alternative to conventional PSCs due to their unique properties such as excellent stability behavior to be potential for commercialization to produce green energy for human industries. One of the most crucial disadvantages of carbon derivatives as HSMs in CPSCs is their low hole mobility, which in the current study has been targeted. In the current study, to increase the efficiency of CPSCs, net carbon nanotubes (CNTs) were doped with nonmetallic fluorine via a facile synthesis method. It was found that introducing fluorine-doped CNTs (F-CNTs) as HSM for MAPbI3 perovskite could reach up to an efficiency of 15.29%, higher than the efficiency of 13.70% in devices with a net CNT layer. By doping CNTs with fluorine, the charge-transfer resistance and series resistance are reduced, resulting in lower charge recombination at the perovskite/CNT interface Also, the CPSCs with F-CNT film were more stable in ambient air because the F-CNTs covered more of the perovskite layer. The future trend of CNT-based PSCs is expected to focus on improving their performance, and exploring their potential for various optoelectronics. [ABSTRACT FROM AUTHOR]

Composites of polyaniline and cobalt ferrite have been prepared using in-situ chemical polymerization to study their supercapactive behaviour with electrical, thermal, and magnetic properties in light of the progressing applications of conducting polymers. X-ray diffraction and Fourier transform infrared spectroscopy were used to confirm the synthesis of materials and to carry out their structural studies. Scanning electron microscope image clears the embeddedness of nanoparticles of cobalt ferrite in polyaniline matrix in such a way that surface area of the rod-shaped polyaniline gets enhanced. Thermogravimetric analysis has been employed for measuring decomposition temperature of samples. Optical band gap of polyaniline is found to reduce from 1.63 to 1.49 eV due to embedment of cobalt ferrite nanoparticles. Cole-Cole plots fitted with two sub circuits is showing grain boundary like structure of synthesized samples. Conducting attributes of PANI/Cobalt ferrite composites have been studied in detail w.r.t. frequency. Magnetic properties at ± 10 KOe established the magnetic attributes in composites due to inclusion of ferrite particles. The electrochemical studies done over scan rate from 2 to 10mV/s, of prepared materials for specific capacitance were found to be significantly high for composites as compare to pure conducting polyaniline or ferrites. This study promotesthe synthesized materials as new opportunities for the energy storage devices. [ABSTRACT FROM AUTHOR]

Undoped and doped polyvinyl alcohol (PVA)/ polyvinylpyrrolidone (PVP)/polyethylene glycol (PEG) blends with nano Zn0.75−xCd0.25CoxS (x = 0, 0.05, 0.1, 0.15) were fabricated using a solid state reaction route at low temperature and casting method. Rietveld method was applied to obtain the structure and microstructure properties of the nanofiller Zn0.75−xCd0.25CoxS. X-ray diffraction analysis (XRD), Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) techniques were used to confirm the presence of the nanofiller in the host blend matrix. The effect of the cobalt contents in the nanofiller on the decomposition temperature and thermal stability of the different blends was explored. The activation energies of different blends were determined using the Coats–Redfern relationship. The different optical parameters and the emitted fluorescence colors of the doped blends were affected by the amount of cobalt (Co) in the nanofiller. The direct and indirect values for an undoped blend are 5.22 and 4.96 eV, respectively. The lowest direct and indirect optical band gap values are 4.13 and 2.13 eV as the amount of Co became 5%. Blends with 5% Co exhibited the highest refractive index. The influence of the cobalt amount in the nanofillers on the electric dielectric constant, ac conductivity and electric modulus of the blends was also investigated. [ABSTRACT FROM AUTHOR]

Most heterogeneous catalytic processes occur between combinations of gases, liquids, and solids at elevated temperatures. They play a critical role for society in energy production, health care, a cleaner environment, industrial products, food, fuel cells, battery technologies, and photocatalysis. Dynamic gas–solid catalyst reactions take place at the atomic level, with active catalyst structures forming, and often also progressively and competitively deactivating, under reaction conditions. There is increasing evidence that single atoms and small clusters of atoms can act as primary active sites in catalytic reactions. Understanding and directing the reactions at the atomic level under controlled operating conditions are crucial for the development of improved materials and processes. We review advances in dynamic in situ microscopy for directly probing heterogeneous catalysis at the atomic level in live action and real time. Benefits include new knowledge and improved management of process fundamentals for greater efficiency and sustainability. [ABSTRACT FROM AUTHOR]