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[Display omitted] Electroactive coatings for smart wearable textiles based on a furan bio-epoxy monomer (BOMF) crosslinked with isophorone diamine (IPD) and additivated with carbon nanotubes (CNTs) are reported herein. The effect of BOMF/IPD molar ratio on the curing reaction, as well as on the properties of the crosslinked resins was first assessed, and it was found that 1.5:1 BOMF/IPD molar ratio provided higher heat of reaction, glass transition temperature, and mechanical performance. The resin was then modified with CNT to prepare electrically conductive nanocomposite films, which exhibited conductivity values increased by eight orders of magnitude upon addition of 5 phr of CNTs. The epoxy/CNT nanocomposites were finally applied as coatings onto a cotton fabric to develop electrically conductive, hydrophobic and breathable textiles. Notably, the integration of CNTs imparted efficient and reversible electrothermal behavior to the cotton fabric, showcasing its potential application in smart and comfortable wearable electronic devices. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have shown significant potential in hybrid capacitive deionization owing to their unique structure and adjustable pore size. However, their limited electronic conductivity and electrochemical stability hinder their practical application. In this study, we developed hierarchically structured Ni-MOF nanosheets interconnected by carbon nanotubes (Ni-MOF@CNT) through a one-pot hydrothermal reaction. By combining the porous structure of Ni-MOF with the synergistic effect of Ni2+ ions and CNTs, the Ni-MOF@CNT electrode with fast interfacial charge transfer demonstrates a high desalination capacity of 47.58 mg g–1 and excellent cycling stability. Additionally, the Ni-MOF@CNT electrode demonstrates a remarkable Li+ ion extraction capacity of 30.29 mg g–1. [ABSTRACT FROM AUTHOR]

Low-velocity impact on fiber-reinforced polymer (FRP) composites may cause subsurface interface delaminations. In the case of such multiple delaminations, neighboring delaminations may grow and coalesce into larger delamination under post-impact loading. The resistance to such growth is substantially influenced by the strength and stiffness of epoxy resins used in FRP composite laminates. Therefore, the current study attempts to determine how adding carbon nanotubes (CNTs) to epoxy might potentially enhance the resistance to such delaminations. A three-dimensional (3D) finite element analysis has been carried out for laminates having single embedded delamination as well as two neighboring embedded delaminations to determine the interlaminar stresses and strain energy release rate using virtual crack closure integral. Results from the current analysis show that while parameters like shape, size, and relative spacing of delamination influence the growth, however in all the cases, adding CNTs to epoxy significantly improves the resistance to the growth of both single and interacting delaminations. The effect is observed to be more pronounced when the delaminations are closely spaced and tend to coalesce into a large delamination. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) are one‐dimensional nanomaterials with a hollow structure, high specific surface area and excellent chemical conductivity, which show great potential for application in the field of humidity‐sensitive responsive materials and humidity sensors. In this paper, CNTs were composited with a hybrid copolymer (HAC) of octavinyl POSS/acrylate to prepare the hybrid copolymer composites HAC/CNTs and their humidity sensors, which demonstrated exceptional thermal stability and fast response speed. Among them, acrylic resin serves as a humidity‐sensitive material; POSS introduce a stable three‐dimensional cage skeleton structure to the material; and CNTs are used as conductive fillers, which further enhance the stability of the material, as well as improve the sensitivity and humidity‐sensitive response speed of the material. The experimental findings indicate that the HAC/8.0% CNTs composite material exhibits a remarkable sensitivity of 119.94 KΩ/%RH within the humidity range of 11%–95%RH. Compared with HAC, HAC/8.0% CNTs demonstrate a significant reduction in response/recovery time from 16.0 s/70.0 s to 0.8 s/80.0 s, representing a considerable improvement in response speed; the wet hysteresis is reduced from 0.88 %RH to 0.77 %RH; and the temperature change coefficient is reduced from 0.035 %RH/°C to 0.008 %RH/°C over the temperature range of 20–60°C, indicating superior stability against temperature variation. Meanwhile, the humidity response mechanism of HAC/CNTs was discussed by using complex impedance spectrum. The hybrid copolymer composites, HAC/CNTs, that were prepared in this study have tremendous potential in the development of advanced, high‐performance, and miniaturizable humidity sensing technologies. Highlights: A hybrid copolymer composite humidity‐sensitive material HAC/CNTs is prepared.HAC/CNTs are compounds consisting of CNTs and POSS/acrylate hybrid copolymer.POSS improve the skeleton structural stability of acrylic resins.CNTs enhance the sensitivity and response speed of humidity sensor.The HAC/8.0% CNTs have higher response stability and faster response speed. [ABSTRACT FROM AUTHOR]

Carbon is one of the most abundant minerals in the universe. The world’s energy needs are being unmet due to the exponential rise in population. Since its inception 20 years ago, carbon and its allotropes, including fullerenes, carbon nanotubes, and graphene, have been marketed as potential energy storage and generation materials. By solving important issues like accumulation and inadequate thermodynamic compatibility, carbon fiber, expanded graphite, and carbon nanotubes are promising functional materials that can be used to improve the performance of bipolar plates further. There are several potential uses for carbon-based nanomaterials (CBNMs) in the energy area. This mini-review provides an overview of the synthetic routes employed for producing CBNMs, categorizing them based on their types, elucidating their diverse applications in fuel energy systems, and emphasising the uses of CBNMs in energy. The advantages and disadvantages of several synthetic processes have been examined and compared. The types of CBNMs, like carbon nanotubes, graphene, carbon dots, and fullerenes, are explored in terms of their unique structural properties and fabrication methods. Furthermore, the utilization of CBNMs in fuel energy systems, such as fuel cells, energy storage devices, and catalysis, is comprehensively reviewed. [ABSTRACT FROM AUTHOR]

It is expected that composites made of carbon nanotubes (CNT) and copper (Cu) display both mechanical and electrical properties, but the low damage dispersion and high-quality composite of high-content CNTs have always been research difficulties. In this paper, high-content CNTs/Cu composites were prepared. The effects of the sintering method, sintering temperature, directional rolling and the CNTs' content on the relative density, hardness and electrical conductivity of the composites were studied. The uniform dispersion of high-content CNTs in Cu matrix was achieved by ball milling, sintering and rolling, and the processes did not cause more damage to the CNTs. The properties of composites prepared by spark plasma sintering (SPS) and vacuum hot pressing sintering (HPS) were compared, and the optimum process parameters of SPS were determined. When the CNTs' content is 2 wt.%, the hardness is 134.9 HBW, which is still 2.3 times that of pure Cu, and the conductivity is the highest, reaching 78.4%IACS. This study provides an important reference for the high-quality preparation and performance evaluation of high-content CNTs/Cu composites. [ABSTRACT FROM AUTHOR]

Element substitution in Cu2ZnSnS4‐like chalcogenides offers the potential to create alternative low‐cost photovoltaic and thermoelectric materials with tunable properties. In this work, the “green” synthesis of colloidal cation‐substituted Cu–Ni–Sn–S nanocrystals (CNTS NCs) in aqueous solutions using thioglycolic acid as a stabilizer is reported for the first time. The structural and optical properties of CNTS NCs are studied in colloidal solutions and thin films, and are compared with those of Cu–Zn–Sn–S (CZTS) NCs obtained under similar conditions. The NC sizes of both compounds are estimated to be in the range of 1.5–2.5 nm. Both NCs exhibit strongly non‐stoichiometric composition and a structure corresponding to cationically disordered kesterite Cu2ZnSnS4, which are common features of such quaternary metal‐based chalcogenides. The phonon Raman spectra of CNTS and CZTS NCs exhibit very similar lineshapes, but the CNTS phonon band has a larger width and lower frequency, presumably due to stronger cation disorder. The absorption of both types of NCs extends continuously through the visible range with an estimated bandgap of ≈2.2 eV and sub‐bandgap absorption due to an Urbach tail. The absorption coefficient of CNTS is determined to be α > 102 cm−1 at 700 nm and α > 104 cm−1 at 400 nm. [ABSTRACT FROM AUTHOR]

Composite plates comprising a blend of rare earth neodymium-(Nd) doped M-type barium ferrite (BaM) with CNTs (carbon nanotubes) and polyethylene WERE synthesized through a self-propagating reaction and hot-pressing treatment. The plates' microscopic characteristics were analyzed utilizing X-ray diffraction (XRD), Fourier transform infrared spectrophotometry (FTIR), thermo–gravimetric analysis (TGA), Raman, and scanning electron microscopy (SEM) analytical techniques. Their microwave absorption performance within the frequency range of 8.2 to 18 GHz was assessed using a vector network analyzer. It showed that CNTs formed a conductive network on the surface of the Nd-BaM absorber, significantly enhancing absorption performance and widening the absorption bandwidth. Furthermore, dielectric polarization relaxation was investigated using the Debye theory, analyzing the Cole–Cole semicircle. It was observed that the sample exhibiting the best absorbing performance displayed the most semicircles, indicating that the dielectric polarization relaxation phenomenon can increase the dielectric relaxation loss of the sample. These findings provide valuable data support for the lightweight preparation of BaM-based absorbing materials. [ABSTRACT FROM AUTHOR]

The CNTs/nano ZnO/SBS/asphalt composites with different CNTs content were prepared by solution casting method. The morphology of the composite shows that the dispersion of SBS is improved by the synergistic hybrid effect of CNTs and nano ZnO. Good dispersion is beneficial for enhancing the adsorption of lightweight components, thereby effectively improving the temperature range of asphalt use. At the same time, the increase in the proportion of asphaltene leads to an increase in the number of honeycomb structures, the surface roughness of composite materials, as well as the water contact angle. [ABSTRACT FROM AUTHOR]

Herein, a facile coprecipitation route was followed to synthesize Zn-Ag co-doped barium hexaferrite (ABHF) and its nanocomposite with carbon nanotubes (CNTs) using the ultrasonication method. Various characterization techniques were used to analyze the structure and optical properties. The bandgap energy of BHF and ABHF was 2.16 eV, and 2.09 eV respectively. Diclofenac sodium and acetaminophen were used to study the photocatalytic activity of the synthesized samples. It was noted that the bare sample showed 29.46 % and 44.96 % degradation for diclofenac sodium and acetaminophen respectively. The highest catalytic activity was shown by the nanocomposite (ABHF@CNTs) that degraded 70.87 % and 84.34 % of diclofenac sodium and acetaminophen respectively. Photodegradation of diclofenac sodium and acetaminophen (pharmaceutical drugs) was increased due to a reduction in bandgap energy (Eg), increased surface area, and prolonged e--h+ pair recombination of the synthesized samples. [ABSTRACT FROM AUTHOR]

The synthesis of zeolite nanoparticles is studied comprehensively by adding an organic template as a reflux method, extracted from crystals. The zeolite nano-crystals are quite effectively synthesized by incorporating silica, organic template, and alkali metal. The tetrapropylammoniumhydroxide, tetrapropylammoniumbromide and tetraethyl orthosilicate (TEOS) as organic templates are added for the assistance of zeolite (albite) crystals. A cross-linker TEOS is also mixed. Adding carbon nanotubes and graphene oxide made the morphology of albite more interesting. Nucleation time is an important feature for the formation of albite crystals. The albite nano-shaped crystal is developed for instance when reaction time is less than 240 h, after this period crystal size increases with time. Batch 1 of zeolite is prepared with additives for testing its morphology, like surface area, particle size shape, and crystal geometry. The general trend (e.g., pore volume, percentage composition, particle size, geometry) of zeolite nano-crystal is explained by the help of robust techniques such as Fourier transform infrared spectroscopy, X-ray diffraction, Brunauer–Emmett–Teller, energy-dispersive X-ray spectroscopy, and scanning electron microscopy.

In this study, eutectic-Bi–Sn-coated basalt fiber (BF)-reinforced carbon nanotube (CNT)/epoxy hybrid composites were fabricated for dual functionality, i.e., in managing and shielding clinical X-ray radiation and electromagnetic interference (EMI). BF mats were coated with Bi–Sn nanoparticles and subsequently layered with multi-walled CNTs mixed epoxy resin using the vacuum-assisted resin transfer method. High resolution field emission scanning electron microscopy revealed a good dispersion of Bi–Sn nanoparticles over BF and, CNTs within the epoxy matrix. X-ray diffraction analysis confirmed the presence of Bi–Sn, basalt, and CNT phases in the composites. High-resolution Raman spectroscopy revealed characteristic peaks corresponding to the CNTs, epoxy, and Bi–Sn phases. EMI total shielding effectiveness (SET) analysis in the X-band frequency range (8.2–12.4 GHz) demonstrated that the Bi–Sn/BF/CNT/epoxy (S3) exhibits the highest SET value of 30.4 dB, which is attributable to the synergistic effect of the Bi–Sn coating and CNT filler. Analysis of X-ray-radiation leakage revealed that all the composite samples effectively attenuated X-rays with minimal leakage, limited to 6.8 mR. These results indicate the potential of these composites for applications as eco-friendly, non-toxic, and lead-free various industries including healthcare, electronics, aerospace, and defense.

Casson fluids containing carbon nanotubes of various lengths and radii on a moving permeable plate reduce friction and improve equipment efficiency. They improve plate flow dynamics to improve heat transfer, particularly in electronic cooling and heat exchangers. The core objective of this study is to investigate the heat transmission mechanism and identify the prerequisites for achieving high cooling speeds within a two-dimensional, stable, axisymmetric boundary layer. This study considers a sodium alginate-based nanofluid containing single/multi-wall carbon nanotubes (SWCNTs/MWCNTs) and Casson nanofluid flow on a permeable moving plate with varying length, radius, and nonlinear thermal radiation effects. The plate has the capacity to move either parallel to or perpendicular to the free stream. The governing partial differential equations for the boundary layer, which are interconnected, are transformed into standard differential equations. These equations are then numerically solved using the Runge–Kutta fourth-order scheme incorporated in the shooting method. This research analyses and graphically displays the effects of factors including mass suction, nanoparticle volume fraction, Casson parameter, thermal radiation, and temperature ratio. Additionally, a comparison is made between the present result and the previous finding, which presented in a tabular format. The coefficient of skin friction decreases in correlation with an increase in Casson fluid parameters and Prandtl number. Heat transfer rate decreases with a variation in viscosity parameter, while it is increasing with an increase in Prandtl number. In addition, this study demonstrates that heat transfer rate for MWCNT is significantly higher than that of SWCNT nanoparticles. Thermal radiation and temperature ratio reduce the heat transfer rate, whereas nanoparticle volume fraction and Casson parameter enhance it over a shrinking surface.

Abstract Carbon nanotube (CNT) has fostered research as a promising nanomaterial for a variety of applications due to its exceptional mechanical, optical, and electrical characteristics. The present article proposes a novel and comprehensive micromechanical framework to assess the viscoelastic properties of a multiscale CNT-reinforced two-dimensional (2D) woven hybrid composite. It also focuses on demonstrating the utilisation of the proposed micromechanics in the dynamic analysis of shell structure. First, the detailed constructional attributes of the proposed trans-scale composite material system are described in detail. Then, according to the nature of the constructional feature, mathematical modelling of each constituent phase or building block’s material properties is established to evaluate the homogenised viscoelastic properties of the proposed composite material system. To highlight the novelty of this study, the viscoelastic characteristics of the modified matrix are developed using the micromechanics method of Mori–Tanaka (MT) in combination with the weak viscoelastic interphase (WI) theory. In the entire micromechanical framework, the CNTs are considered to be randomly oriented. The strength of the material (SOM) approach is used to establish mathematical frameworks for the viscoelastic characteristics of yarns, whereas the unit cell method (UCM) is used to determine the viscoelastic properties of the representative unit cell (RUC). Different numerical results have been obtained by varying the CNT composition, interface conditions, agglomeration, carbon fibre volume percentage, excitation frequency, and temperature. The influences of geometrical parameters like yarn thickness, width, and the gap length to yarn width ratio on the viscoelasticity of such composite material systems are also explored. The current study also addresses the issue of resultant anisotropic viscoelastic properties due to the use of dissimilar yarn thickness. The results of this micromechanical analysis provide valuable insights into the viscoelastic properties of the proposed composite material system and suggest its potential applications in vibration damping. To demonstrate the application of developed novel micromechanics in vibration analysis, as one of the main contributions, comprehensive numerical experiments are conducted on a shell panel. The results show a significant reduction in vibration amplitudes compared to traditional composite materials in the frequency response and transient response analyses. To focus on the aspect of micromechanical behaviour on dynamic response and for the purpose of brevity, only linear strain displacement relationships are considered for dynamic analysis. These insights could inform future research and development in the field of composite materials.

Lithium‐sulfur batteries (LSBs) are greatly promising next‐generation energy storage systems due to their high theoretical specific capacities and energy density. However, the dissolution of lithium polysulfides (LIPs) causees low capacity and short lifespan, impeding the practical application of LSBs. To address this challenge, the composites of oxygen‐doped porous carbon nanotubes (CNTs) wrapped in Bi2O3 were synthesized by the calcinating method (CNTs@Bi2O3). The CNTs@Bi2O3 composites as absorbent immobilize LIPs via the physical limitations of porous CNTs and the chemical adsorption of Bi2O3 and carbon‐oxygen polar bond. After loading sulfur, the CNTs@Bi2O3/S composites with the encapsulated structure can provide a large space to withstand the significant volume expansion during the electrochemical reaction process, ensuring the stability of the electrode structure. Thus, the batteries with CNTs@Bi2O3/S exhibit a high capacity (1232 mA h g−1 at 0.1 C) and good cycle stability (639.1 mA h g−1 after 150 cycles at 0.5 C). This work presents an innovative design suitable for the encapsulated structure of Bi2O3, serving as a valuable reference for the development of Bi2O3 in LSBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn2+ substitution generates beneficial holes to accelerate electron transport while supporting the structure to stabilize the framework. • Al 2 O 3 coating has the triple effect of reducing HClO 4 concentration, inhibiting the dissolution of Mn and acting as a conductive agent. • NVMP@CNTs@1wt.%Al 2 O 3 possesses a porous structure, effectively promoting the rapid Na+ transport. • The excellent structural stability is confirmed by in situ XRD. • NVMP@CNTs@1wt.%Al 2 O 3 reveals a remarkable sodium storage property in both half and full cells. Na 3 V 2 (PO 4) 3 (NVP) encounters significant obstacles, including limited intrinsic electronic and ionic conductivities, which hinder its potential for commercial feasibility. Currently, the substitution of V3+ with Mn2+ is proposed to introduce favorable carriers, enhancing the electronic conductivity of the NVP system while providing structural support and stabilizing the NASICON framework. This substitution also widens the Na+ migration pathways, accelerating ion transport. Furthermore, to bolster stability, Al 2 O 3 coating is applied to suppress the dissolution of transition metal Mn in the electrolyte. Notably, the Al 2 O 3 coating serves a triple role in reducing HClO 4 concentration in the electrolyte, inhibiting Mn dissolution, and functioning as the ion-conducting phase. Likewise, carbon nanotubes (CNTs) effectively hinder the agglomeration of active particles during high-temperature sintering, thereby optimizing the conductivity of NVP system. In addition, the excellent structural stability is investigated by in situ XRD measurement, effectively improving the volume collapse during Na+ de-embedding. Moreover, the Na 3 V 5.92/3 Mn 0.04 (PO 4) 3 /C@CNTs@1wt.%Al 2 O 3 (NVMP@CNTs@1wt.%Al 2 O 3) possesses unique porous structure, promoting rapid Na+ transport and increasing the interface area between the electrolyte and the cathode material. Comprehensively, the NVMP@CNTs@1wt.%Al 2 O 3 sample demonstrates a remarkable reversible specific capacity of 122.6 mAh/g at 0.1 C. Moreover, it maintains a capacity of 115.9 mAh/g at 1 C with a capacity retention of 90.2 mAh/g after 1000 cycles. Even at 30 C, it achieves a capacity of 87.9 mAh/g, with a capacity retention rate of 84.87 % after 6000 cycles. Moreover, the NVMP@CNTs@1wt.%Al 2 O 3 //CHC full cell can deliver a high reversible capacity of 205.5 mAh/g at 0.1 C, further indicating the superior application potential in commercial utilization. [ABSTRACT FROM AUTHOR]

The CNTs/MgAl2O4 whiskers composite reinforcement was prepared by catalytic carbon‐bed sintering and added to low‐carbon Al2O3‐C refractories to enhance the thermal shock resistance of refractories. The effects of Ni(NO3)2·6H2O content on the phase and microstructure of CNTs/MgAl2O4 were investigated. The nano‐indentation technology was used to quantitatively evaluate the effect of CNTs/MgAl2O4 on the thermal shock resistance of low‐carbon Al2O3‐C refractories, and the toughening mechanism of CNTs/MgAl2O4 on refractories was further investigated. The results revealed that the inner and outer diameters of the CNTs were approximately 5.69 and 16.26 nm, respectively. The CNTs winded around interlocking structural MgAl2O4 whiskers with a high aspect ratio (>100), which was beneficial to the dispersion of CNTs in the refractory matrix. The thermal shock resistance of low‐carbon Al2O3‐C refractories was significantly improved by adding 3.0 wt.% of CNTs/MgAl2O4 (named C3). The specific fracture energy of refractory matrix and residual strength ratio of C3 reached 141 N·m−1 and 39.2%, which were 29.4% and 97.0% higher than those of the blank sample (109 N·m−1 and 19.9%), respectively. This is because the refractory matrix was significantly reinforced by CNTs and MgAl2O4 whiskers, promoting the occurrence of "bridging" and "crack deflection" and the generation of microcracks in the refractory matrix. [ABSTRACT FROM AUTHOR]

This current research examines the behaviour of dusty Jeffrey fluid across an inclined stretching sheet with CNTs as well as aligned magnetohydrodynamic (MHD). By utilising the proper similarity transformation variables, the governing partial differential equations (PDEs) of the problem are converted to ordinary differential equations (ODEs). Then, the numerical results are produced by using the Runge-Kutta-Fehlberg (RKF45) approach with the aid of the MAPLE software. The findings include the visual illustrations of the impacts on the velocity and temperature profiles for several pertinent parameters. It clearly shows that the decline in velocity profile of fluid phase was caused by the rise in aligned angle, ratio of relaxation to retardation times, magnetic field and fluid particle interaction parameters. Meanwhile, for every parameter that is involved excluding ratio of retardation time in the fluid, the temperature profile rises in both the fluid and dusty phases. The results of this study add a unique perspective to the existing literature by offering fresh insights on the influence of CNTs and dust particles, examining their impact on two-phase flowover an inclined stretching sheet. This understanding can be utilized in the real-time application where rapid and efficient thermal management is critical such as electronics cooling or energy conversion systems. Furthermore, the inclusion of viscous dissipation andNewtonian heating (NH) effects contributes to the novelty of the research, providing a comprehensive understanding of the complex interactions in this unique fluid flow scenario. [ABSTRACT FROM AUTHOR]

Although asbestos fiber is used for autobrake pad production due to its heat resistance capacity, it is associated with a challenge of health risk (cancerogenic in nature). This health risk associated with asbestos-based autobrake pads has presented polymeric materials as a better candidate for the application due to their eco-friendliness, lightweight, chemical inertness, easy of processing, etc. However, polymers are associated with low wear and low mechanical properties, which are vital properties for autobrake pads. Therefore, this study developed EP nanocomposites reinforced with a low content of carbon nanotubes (CNTs) and eggshell (ES) attached cow bone (CB) particles denoted as (ES@CB) as agro-waste/sustainable materials for the manufacturing of autobrake pads. The hybrid ternary nanocomposites were developed via solution mixing and casting. Scanning electron microscope (SEM) revealed the 1-D structure of the CNTs, and relatively spherical shapes of ES and CB particles, and microstructures of the developed nanocomposites. The nanocomposite showed a low coefficient of friction and a reduction in wear rate in the range of 1.14 × 10−4 mm3/Nm for pure EP to 5.45 × 10−6 mm3/Nm for EP/0.4wt%CNTs-10wt%ES@CB nanocomposite, while the elastic modulus and hardness increased from 1.84 GPa and 128.64 MPa for pure EP to 4.41 GPa and 252.88 MPa for EP/0.2wt%CNTs-20wt%ES@CB nanocomposite, respectively. The comparison of the wear response of the developed nanocomposites with the current asbestos-based brake pads show that the developed epoxy nanocomposites from agro-waste materials are potential option for the manufacturing of autobrake pads, which will ensure sustainability, health risk-free, and environmentally friendly. [ABSTRACT FROM AUTHOR]

This study reports the successful synthesis of a new copolymer based on N-vinylcarbazole (NVC) and Eriochrome black T (EBT) monomers as well as (nano)composites based on carbon nanotubes (CNTs) as nano-filler. For this, the copolymer poly (N-vinylcarbazole-co-black eriochrome T), noted poly (NVC-co- EBT) was synthetized by electro-copolymerization of the selected monomers deposited on Indium Tin Oxide (ITO) electrode in lithium perchlorate electrolyte, using cyclic voltammetry method. The (nano)composites poly (NVC-co- EBT)/CNTs were synthesized in the same conditions as the copolymer, in presence of different CNTs content (3 wt. %, 5wt. %, 10 wt. %). The electrodeposition of the copolymer (nano)composites was successfully occurred after the first cycle and thin films were formed. Remarkably, their thickness was increased by increasing the cycle's numbers. The electro-chemical properties of the new copolymer, as well as (nano)composites, were investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The synthesized (nano)composites display a diffusion process related to Warburg impedance, for a low and intermediate frequencies but they exhibit a capacitive behavior at high frequencies which implies the increase of the conductivity character. Furthermore, the obtained copolymer poly (NVC-co- EBT) exhibits low transmittance in the UV–visible region, with a gap energy value of 1.95 eV. Interestingly, by doping with CNTs nano-filler at 3 wt. % and 5 wt. %, the energy gap was relatively increased to achieve a value of 2.41 eV and 2.71 eV, respectively. Therefore, at 10 wt. % of CNTs, the energy gap of the copolymer (nano)composite becomes equal to zero. Consequently, these results highlight the importance of the synthesized copolymer to have a semi-conductor and conductor behavior according to the CNTs content in the material, which promote its application in many devices, as photocatalysis and photovoltaic fields. [ABSTRACT FROM AUTHOR]

The current study investigates the two-dimensional incompressible viscous flow of CNTs (carbon nanotube) blood base hybrid nanofluids, both multi wall and single wall, with the considered impact of MHD, couple stress, Marangoni convection, thermal radiation and viscous dissipation. Appropriate similarity transformation is used to convert the governing flow problem partial differential equation to dimensionless nonlinear ordinary differential equations. We solve this dimensionless coupled equation, one for temperature and one for velocity, using the homotopy analysis method (HAM). The flow characteristics, such as temperature and velocity profiles, are studied and simulated using a physical description in response to changes in developing factors. Based on the data presented, it can be concluded that CNT is a more dependable material for industrial and technological applications due to its superior heat transfer properties. For hybrid nanofluids, a decrease in the temperature curve is observed with increasing prandtl number and enhancement with the increasing value of thermal radiation, viscous dissipation and temperature ratio factors. By enhancing the volume friction parameter, coupling stress parameter and magnetic parameter increase, the hybrid nanofluid velocity curve falls. This paper also investigates the blood-based hybrid nanofluid's thermal performance as measured by the local skin friction coefficient and Nusselt number. The major outcome of this research work is to increase the effectiveness of heat exchangers, cooling systems and thermal management equipment. It improved heat transfer capability results from the base fluid's increased thermal conductivity. [ABSTRACT FROM AUTHOR]

This study analyzes the nonlinear dynamic stability of carbon nanotube reinforced composite (CNTRC) piezoelectric viscoelastic nano/micro plate under time dependent harmonic compressive biaxial mechanical loading. The nano/micro plate is single-layer with a uniform and rectangular cross section. Polyvinylidene fluoride (PVDF) is the material used for the nano/micro plate. Also, it is located on a nonlinear viscoelastic piezoelectric foundation made of Zinc Oxide (ZnO). Single-walled carbon nanotubes (SWCNTs) have been used to strengthen nano/micro plate. Using Kelvin-Voigt model, the material properties of the system are assumed to be viscoelastic. Nano/micro plate is subjected to 2D magnetic field and electric potential. Magnetic field effects are incorporated using Maxwell's relations. An alternating and direct voltage is applied to the nano/micro plate and also smart foundation in thickness direction. Eshelby-Mori-Tanaka approach is used to estimate the effective elastic properties. Additionally, follower force and uniform thermal gradient is applied to nano/micro plate in this study. The nonlinear strain–displacement relations are based on the Von-Kármán theory. According to classical, first order, third order, sinusoidal, parabolic, hyperbolic and exponential shear deformation plate theories, a new formulation is proposed incorporating surface stress effects through the Gurtin-Murdoch elasticity theory. In order to consider small scale parameters, this research is based on modified strain gradient theory (MSGT). Using the energy method and Hamilton's principle, the non classical governing equations are derived. For nano/micro plate, simply supported boundary conditions are considered. For the purpose of solving differential equations, an analysis based on Galerkin procedure and finally the Bolotin method will be used to obtain the dynamic instability region (DIR). It is the objective of this study to investigate the impact of such parameters as small-scale parameters, alternating and direct applied voltage, intensity of magnetic field, surface effects, thermal environment and static load factor on the DIR. This study revealed that taking into account the smart foundation reduces the area of dynamic instability region by more than 60% for a constant intensity of magnetic field. The stability responses are also more convergent with the smart foundation. Additionally, the range is moved toward higher excitation frequencies and greater system stability. Validation of answers based on reliable scientific articles is one of the final stages of this research. These results can be used to design nano/micro electromechanical systems. [ABSTRACT FROM AUTHOR]

So far, severe capacity decay induced by the polysulfide shuttle effect still remains a great obstacle to the commercialization of lithium–sulfur batteries (LSBs). Herein, Ni-doped ZIF67 (ZIF67/Ni) was prepared by the coprecipitation method, and then (Co, Ni)-NC/CNT composites in which in situ formed Co–Ni nanoparticles and CNTs are embedded in the 3D N-doped nanoporous carbon network structure were successfully obtained by a two-step carbonization heat treatment, without shrinkage and collapse of the skeleton. The synergistic catalysis of Co–Ni bimetal significantly promotes redox kinetics, renders strong chemisorption toward polysulfides, and reduces the CVD growth temperature of CNTs (600 °C). Furthermore, the 3D conductive network of the N-doped C skeleton embedded with CNTs and Co–Ni nanoparticles ensures fast electron/ion transportation and structural stability of the skeleton. As the cathode host of LSBs (Co, Ni)-NC/CNT composites exhibit excellent rate performance (1352–590.6 mA h g–1 at 0.5–10 A g–1) and superior cycling stability (reversible capacity of 744 and 544 mA h g–1, with decay rates of 0.031% and 0.029% per cycle at 1 and 5A g–1 for 1000 cycles, respectively). The simple and scalable construction strategy of MOF derivatives shows an important application prospect in electrochemical energy storage, catalysis, electromagnetic shielding/microwave absorption, etc. [ABSTRACT FROM AUTHOR]

A fine study of the interfacial part in the silicon carbide fiber (SiCf) reinforced silicon carbide (SiC) composites was conducted by transmission electron microscopy. The boron nitride (BN) and carbon nanotubes (CNTs) were progressively coated on the SiCf by chemical vapor deposition method to form a hierarchical structure. Three composites with different interfaces, SiCf–CNTs/SiC, SiCf@BN/SiC, and SiCf@BN–CNTs/SiC, were fabricated by polymer infiltration and pyrolysis method. The interfaces and microstructures of the three composites were carefully characterized to investigate the improvement mechanism of strength and toughness. The results showed that BN could protect the surface of SiCf from corrosion and oxidation so that improved the possibility of debonding and pullout. CNTs could avoid the propagation of cracks in the composites so that improved the damage resistance of the matrix. The synergistic reinforcement brought by BN and CNTs interfaces made the SiCf@BN–CNTs/SiC composites with a tensile fracture strength as high as 359 MPa, with an improvement of 23% compared to that of SiCf@BN/SiC. [ABSTRACT FROM AUTHOR]

Herein, MgO–C refractories were prepared using fused magnesite, aluminum powder, and silicon powder as antioxidants and different kinds of graphite as carbon sources at 1200°C–1600°C. The microstructure and mechanical strength of MgO–C refractories were studied. The results showed that using cobalt‐loaded expanded graphite as partial carbon source, carbon nanotubes (CNTs) were formed in situ in MgO–C refractories at 1200°C, and the CNTs gradually reacted with Si to form SiC fibers over 1400°C. Consequently, the mechanical strength of MgO–C refractories was significantly improved. [ABSTRACT FROM AUTHOR]

With the booming development and wide applications of modern communication technology, wearable devices are becoming more and more popular in our life. Meanwhile, the pollution and radiation of electromagnetic wave (EMW) is becoming increasingly prominent and threating to human health, equipment operation and military security. Multi-component regulation and spatial microstructure design of microwave absorption materials is an effective strategy for solving the pollution and radiation of electromagnetic wave. Herein, aramid nanofibers/carbon nanotubes/MnFe 2 O 4 (ACF) composite aerogel were prepared through the combination of freeze-drying technique and hydrothermal method. Impedance matching of aramid nanofibers/carbon nanotubes aerogel is improved by introducing MnFe 2 O 4 particles, inducing to that EMW is more easily incident into aerogel and then attenuated by microwave absorber. In addition, the three-dimensional networks structure of aerogel can enhance the multiple reflection and scattering, and improve the loss capacity of EMW. ACF05 aerogel exhibits a minimum reflection loss of −64.6 dB at 12.0 GHz and broad effective absorption bandwidth of 5.0 GHz under thickness of 2.1 mm. The excellent microwave absorption (MA) performance of ACF aerogel mainly comes from the synergistic effect of three-dimensional networks structure, impedance matching, dielectric loss and magnetic loss. [ABSTRACT FROM AUTHOR]

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Carbon nanotube (CNT) has fostered research as a promising nanomaterial for a variety of applications due to its exceptional mechanical, optical, and electrical characteristics. The present article proposes a novel and comprehensive micromechanical framework to assess the viscoelastic properties of a multiscale CNT-reinforced two-dimensional (2D) woven hybrid composite. It also focuses on demonstrating the utilisation of the proposed micromechanics in the dynamic analysis of shell structure. First, the detailed constructional attributes of the proposed trans-scale composite material system are described in detail. Then, according to the nature of the constructional feature, mathematical modelling of each constituent phase or building block's material properties is established to evaluate the homogenised viscoelastic properties of the proposed composite material system. To highlight the novelty of this study, the viscoelastic characteristics of the modified matrix are developed using the micromechanics method of Mori–Tanaka (MT) in combination with the weak viscoelastic interphase (WI) theory. In the entire micromechanical framework, the CNTs are considered to be randomly oriented. The strength of the material (SOM) approach is used to establish mathematical frameworks for the viscoelastic characteristics of yarns, whereas the unit cell method (UCM) is used to determine the viscoelastic properties of the representative unit cell (RUC). Different numerical results have been obtained by varying the CNT composition, interface conditions, agglomeration, carbon fibre volume percentage, excitation frequency, and temperature. The influences of geometrical parameters like yarn thickness, width, and the gap length to yarn width ratio on the viscoelasticity of such composite material systems are also explored. The current study also addresses the issue of resultant anisotropic viscoelastic properties due to the use of dissimilar yarn thickness. The results of this micromechanical analysis provide valuable insights into the viscoelastic properties of the proposed composite material system and suggest its potential applications in vibration damping. To demonstrate the application of developed novel micromechanics in vibration analysis, as one of the main contributions, comprehensive numerical experiments are conducted on a shell panel. The results show a significant reduction in vibration amplitudes compared to traditional composite materials in the frequency response and transient response analyses. To focus on the aspect of micromechanical behaviour on dynamic response and for the purpose of brevity, only linear strain displacement relationships are considered for dynamic analysis. These insights could inform future research and development in the field of composite materials. [ABSTRACT FROM AUTHOR]

AbstractA study was conducted utilizing computational fluid dynamics (CFD) to explore a novel cooling technique for the central processing unit (CPU), involving the use of carbon nanotubes (CNTs)/H2O nanofluid-fin heat sinks with dimples. Different fin heat sink designs with varying dimple arrangements were created using AutoCAD software. The three-dimensional flow, heat transfer, and mass transfer of the nanofluid within the liquid block were simulated using a finite volume-based CFD code. The study investigated the influence of different nanoparticle concentrations and dimple arrangements on cooling performance, heat transfer coefficient, pumping power, and thermal efficiency. The results revealed that the maximum temperature reduction on the CPU's top surface was approximately 13.1 K for multi-walled carbon nanotube/H2O nanofluids and 14.34 K for single-walled carbon nanotube (SWCNT)/H2O nanofluids. The best thermal efficiencies were achieved using SWCNT (2%)/H2O with three rows of dimples on each fin, resulting in an 8.5% improvement in heat sink performance at Re = 1,500 and an 8.8% improvement at Re = 2,000 compared to fins without dimples. However, it was observed that increasing the number of dimples on the fins led to an increase in pressure drop within the liquid block, necessitating additional pumping power. The simulation results aligned well with earlier experimental data and numerical studies in terms of cooling and heat transfer. [ABSTRACT FROM AUTHOR]

Field emission is an important work mode for electron sources, and carbon nanotubes (CNTs) have been extensively studied for their good emission properties. It is well known that the parameters of the grid deeply influence the field emission performance of CNTs, a relationship that requires further elucidation. Therefore, in this study, the relationship between the grid aperture ratio and electron transmittance was studied through simulations and experiments. This study's results indicate that the electron transmittance improved as the grid aperture ratio increased. Meanwhile, electron beam spot simulations and imaging experiments indicate that an increased grid aperture ratio will expand the cathode electron divergence, leading to a larger electron beam spot size. These results demonstrate that there is a trade-off in maintaining the grid aperture ratio between high electron transmittance and relatively small electron beam spot size, and the optimum grid aperture ratio is between 75% and 85%. These results will provide a reference for the design and optimization of X-ray tubes and other electron sources. [ABSTRACT FROM AUTHOR]

Since hydroelectric power generation was reported, the low power density has been a key challenge for practical application. Realizing a stable power supply and high power density for hydroelectric power generation is the most important point. In this work, a combined water evaporation and capacitor device incorporating nanomaterials was designed, comprising zinc metal, diaphragms, and carbon cloth (CC) that were scraped and coated with treated carbon nanotubes (CNTs). Carbon nanotubes as nanomaterials greatly increase the evaporation rate and power density of the device, with a stable supply of 300 μW/cm2. The electrostatic simulation plots demonstrate that the additional effect of CNTs promotes the transfer of electrons, which is more favorable for the generation of the current potential. The electrostatic simulation plots demonstrate that the additional effect of CNTs promotes the transfer of electrons, which is more favorable to the generation of the current potential. Through simple device integration, the current and other parameters of the device could be flexibly changed according to the actual needs. The current of the device after a series connection could reach a high level of 4 mA. The device has the potential to directly power batteries and other small electronic devices, making it a promising sustainable energy source. [ABSTRACT FROM AUTHOR]

Thermally sprayed ceramic coatings with varied weight percentages of carbon nanotube (CNT) reinforcement were examined. AISI 1020 steel was coated with yttria-stabilized zirconia (ZrO2 + 8% Y2O3) using the atmospheric plasma spraying (APS) method. The study examined the CNT dispersion in the coating microstructure and evaluated the porosity, bond strength, and corrosion resistance of the coating. In addition, the coating thicknesses were measured. The coatings were characterized using a variety of techniques, including optical microscopy, scanning electron microscopy, image analysis, bond strength testing, and corrosion analysis. According to the findings, adding CNTs to the coatings improved their mechanical characteristics, particularly their hardness and wear resistance. Notably, the best levels of hardness and wear resistance were seen in coatings with a 5 percent CNT reinforcement. Additionally, the coatings' corrosion resistance was enhanced by the inclusion of CNTs. The results of this work show that the mechanical and corrosion properties of thermally sprayed ceramic coatings can be successfully improved by the inclusion of CNTs. This means that these CNT-reinforced coatings have a lot of potential for a variety of applications, such as wear-resistant, corrosion-resistant, and thermal barrier coatings. [ABSTRACT FROM AUTHOR]

Owing to their highly predictable porous structures, facile synthesis, and the presence of functional open metal sites, metal–organic frameworks (MOFs) are extensively employed in various fields, including energy storage, catalysis, adsorption, and separation. Nevertheless, the limited hydrolytic stability exhibited by numerous MOFs poses a significant challenge to their practical application. In the present study, we present the synthesis and characterization of a uranyl organic framework (TCPP‐U1) with a highly porous structure, which is constructed by assembling cobalt, uranyl, and the porphyrin ligand 5,10,15,20‐tetra(4‐carboxyphenyl)porphyrin (TCPP). However, TCPP‐U1 demonstrates poor hydrolytic stability when exposed to water (the structure can be destroyed even after 2 min of exposure to water), greatly impeding its potential applications that would benefit from its high surface area. To address this limitation, we developed a hybrid composite by incorporating acid‐treated multi‐walled carbon nanotubes (CNTs) into the TCPP‐U1 framework via a solvothermal method designated as CNTs@TCPP‐U1. Remarkably, the obtained CNTs@TCPP‐U1 composite possesses an identical crystal structure and morphology to the original TCPP‐U1 yet exhibits significant enhancements in hydrolytic stability (the structure remains stable even after 3 days of immersion in water). Furthermore, CNTs@TCPP‐U1 demonstrates a significant photocatalytic effect on the degradation of tetracycline hydrochloride in aqueous solutions. The reaction rate constant (k) for the pseudo‐first‐order kinetic model is 0.0059 min−1. Our findings present a novel perspective for enhancing the stability and expanding the performance of MOFs materials. [ABSTRACT FROM AUTHOR]

It is unknown how the dynamics of ethylene glycol conveying SWCNTs and MWCNTs nanoparticles compare when there is a stratification of concentration and temperature such that the process by which an electric current travels past resistance and transforms some of its energy into heat is essential. The nondimensional governing equations were transformed via similarity transformation and solved numerically through Runge–Kutta 45 Fehlberg method. The computations have shown that the thermal convective term depleted the flow profile of SWCNTs and MWCNTs but boosted the velocity field and thermal diffusion. The induced electromagnetic force by the magnetic field and rising porosity term decrease the characteristic flow dimension. Finally, SWCNTs and MWCNTs are positively influenced by Ohmic magnetic dissipation and negatively influenced by radiation. The SWCNTs and MWCNTs are positively influenced by joule dissipation but negatively influenced by radiation. The thermal convective term reduces the flow profile of SWCNTs and MWCNTs but enhances the velocity field and thermal diffusion. Notably, the Nusselt number proportional to the heat transfer across the motion of SWCNTs nanofluid increases at the rate of 0.55466. Reverse is the case of MWCNTs nanofluid, where the same heat transfer rate decreases with a higher volume fraction at –0.7801. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) are cylindrical nanostructures composed of carbon atoms arranged in a hexagonal lattice, resembling rolled-up sheets of graphene. Since, their discovery in 1991 by Sumio Iijima, CNTs have garnered significant attention due to their exceptional properties, including high mechanical strength, electrical conductivity and thermal stability. This review provides an overview of carbon nanotubes, delving into their structural insights, current applications and future prospects. The structural insights section discusses the atomic structure, chirality, synthesis methods and characterization techniques of CNTs. Current applications span various fields, including electronics, materials science, energy storage, biomedicine and environmental remediation, where CNTs offer enhanced performance and functionality. Challenges and limitations such as dispersion issues and toxicity concerns are also addressed. Finally, future prospects and emerging trends highlight advancements in synthesis techniques, tailored properties for specific applications and the potential for commercialization. Overall, this review underscores the significance of carbon nanotubes in modern science and technology, showcasing their potential to revolutionize industries and address pressing global challenges. [ABSTRACT FROM AUTHOR]

In the electronics industry, binary devices have played a critical role since the development of solid-state transistors. While binary technology associates devices' inherent ability to be either ON or OFF with two logic levels, it offers the least amount of information content per interconnect. There's a strong push to switch to a higher radix logic/number system, which can eliminate or reduce many of the limitations of the binary system, due to the exponential growth of data processing and storage needs. The beyond-binary logic systems are strongly motivated by the need to increase processing speed and information density in future micro and nanoelectronic circuits and systems, as well as the expectation that Moore's law will eventually reach saturation. Due to its ability to increase circuit efficiency, multi-valued logic is becoming more and more significant. Novel post-CMOS devices have been designed and made easier to implement ternary logic thanks to technological advances in material science and nanotechnology. When it comes to low power and energy consumption, low complexity, low on-chip and off-chip interconnections, and high speed, the ternary system outperforms the binary system. In order to provide as a starting point for future research and development in the field of ternary logic circuits, this paper provides a brief overview of the implementation of ternary logic systems and their related benefits for the design of digital logic circuit applications using CMOS and various emerging devices as design elements.

In this work, epoxy resin-based composites reinforced with nanoclays, nanoalumina, carbon nanotubes (CNTs) (0.15, 0.50, and 1.50% vol were submitted to morphological characterization by scanning (SEM) and transmission (TEM) electron microscopies, electrical tests through electrical impedance spectroscopy, and electromagnetic analyses (scattering parameters), in the frequency range of 8.2 to 12.4 GHz. SEM images of the CNT composite revealed nanotube clusters in the matrix. The proximity between the CNTs is corroborated by the increase in the electrical conductivity of the composite due to the formation of a long-range electron transport network, which favored the polarization effect, absorption losses (SEA = 1.33 dB), reflection (SER = 3.38 dB) and reflection loss (RL = -6.61 dB at 10.8 GHz). Composites with nanoclays and nanoalumina showed no significant electrical and electromagnetic results.

This document is an editorial published in the journal Frontiers in Materials. It discusses the significance of carbon-based materials in the field of materials science and their applications in various industries. The editorial highlights the increasing number of publications on carbon materials over time and introduces a research topic dedicated to carbon-based materials. The editorial summarizes five research articles published in this topic, covering topics such as the conversion of waste corn biomass to activated bio-char, pressure mapping using nanocomposite-enhanced foam, synthesis of biochar from lignocellulosic biomass, international research in graphene-oxide based materials, and nitrogen-enriched activated carbon derived from plant biomasses. The editorial concludes by acknowledging the contributions of carbon materials and their potential for future research in energy applications. [Extracted from the article]

Abstract Background The rapid expansion of modern smart applications, demanding faster data transfer and extensive bandwidth, has prompted the development of new-generation networks like 5G and 6G. These networks encompass additional frequency bands such as sub-6 GHz, millimeter waves, and terahertz bands to meet the growing bandwidth requirements. However, despite the substantial bandwidth available in these bands, several challenges must be addressed to overcome unfavorable propagation characteristics. Moreover, numerous applications necessitate wireless devices with antennas that exhibit high flexibility and exceptional radiation responses, particularly when subjected to bending effects. This requirement highlights the importance of polymers-based antennas that can adapt to changing conditions while maintaining optimal performance. The present comprehensive study delves into the performance evaluation of rectangular and circular microstrip antennas utilizing PMMA (polymethyl methacrylate) polymer substrate with varying thicknesses. Results Notably, CNTs (Carbon Nanotubes) are employed as an alternative to traditional copper for the conductive part and ground plane. Both PMMA-based antennas, integrated with CNTs, exhibit a compact footprint of 27.8 × 47.8 × 1.5 mm3 for the circular antenna and 22.8 × 39.5 × 1.5 mm3 for the rectangular antenna. Impressively, the realized gain of both antennas surpasses 5 dBi, demonstrating robust performance in both flat and bending scenarios across different substrate thicknesses. Conclusions The rectangular antenna achieves a bandwidth of approximately 200 MHz, while the circular microstrip antenna showcase annotable bandwidth of 500 MHz. These exceptional outcomes position the two microstrip antennas as highly suitable for a diverse range of emerging applications within the sub-6 GHz band (the frequency range below 6 GHz in the radio spectrum). Thus, the combination of PMMA substrate, CNTs and the compact form factor of the antennas presents a compelling solution for meeting the demands of modern applications requiring efficient wireless communication with enhanced performance and bandwidth.