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The COVID-19 pandemic, caused by the SARS-CoV-2 virus, has led to over six million deaths worldwide. In human immune system, the type 1 interferon (IFN) pathway plays a crucial role in fighting viral infections. However, the ORF8 protein of the virus evade the immune system by interacting with IRF3, hindering its nuclear translocation and consequently downregulate the type I IFN signaling pathway. To block the binding of ORF8–IRF3 and inhibit viral pathogenesis a quick discovery of an inhibitor molecule is needed. Therefore, in the present study, the interface between the ORF8 and IRF3 was targeted on a high-affinity carbon nanotube by using computational tools. After analysis of 62 carbon nanotubes by multiple docking with the induced fit model, the top five compounds with high docking scores of − 7.94 kcal/mol, − 7.92 kcal/mol, − 7.28 kcal/mol, − 7.19 kcal/mol and − 7.09 kcal/mol (top hit1-5) were found to have inhibitory activity against the ORF8–IRF3 complex. Molecular dynamics analysis of the complexes revealed the high compactness of residues, stable binding, and strong hydrogen binding network among the ORF8-nanotubes complexes. Moreover, the total binding free energy for top hit1-5 was calculated to be − 43.21 ± 0.90 kcal/mol, − 41.17 ± 0.99 kcal/mol, − 48.85 ± 0.62 kcal/mol, − 43.49 ± 0.77 kcal/mol, and − 31.18 ± 0.78 kcal/mol respectively. These results strongly suggest that the identified top five nanotubes (hit1-5) possess significant potential for advancing and exploring innovative drug therapies. This underscores their suitability for subsequent in vivo and in vitro experiments, marking them as promising candidates worthy of further investigation. [ABSTRACT FROM AUTHOR]

Functionalizing single‐walled carbon nanotubes (SWCNTs) in a robust way that does not affect the sp2 carbon framework is a considerable research challenge. Here we describe how triiodide salts of positively charged macrocycles can be used not only to functionalize SWCNTs from the outside, but simultaneously from the inside. We employed disulfide exchange in aqueous solvent to maximize the solvophobic effect and therefore achieve a high degree of macrocycle immobilization. Characterization by Raman spectroscopy, EDX‐STEM and HR‐TEM clearly showed that serendipitously this wet‐chemical functionalization procedure also led to the encapsulation of polyiodide chains inside the nanotubes. The resulting three‐shell composite materials are redox‐active and experience an intriguing interplay of electrostatic, solvophobic and mechanical effects that could be of interest for applications in energy storage. [ABSTRACT FROM AUTHOR]

Mechanically interlocked molecules (MIMs) represent an exciting yet underexplored area of research in the context of carbon nanoscience. Recently, work from our group and others has shown that small carbon nanotube fragments—[n]cycloparaphenylenes ([n]CPPs) and related nanohoop macrocycles—may be integrated into mechanically interlocked architectures by leveraging supramolecular interactions, covalent tethers, or metal‐ion templates. Still, available synthetic methods are typically difficult and low yielding, and general methods that allow for the creation of a wide variety of these structures are limited. Here we report an efficient route to interlocked nanohoop structures via the active template Cu‐catalyzed azide‐alkyne cycloaddition (AT−CuAAC) reaction. With the appropriate choice of substituents, a macrocyclic precursor to 2,2′‐bipyridyl embedded [9]CPP (bipy[9]CPP) participates in the AT−CuAAC reaction to provide [2]rotaxanes in near‐quantitative yield, which can then be converted into the fully π‐conjugated catenane structures. Through this approach, two nanohoop[2]catenanes are synthesized which consist of a bipy[9]CPP catenated with either Tz[10]CPP or Tz[12]CPP (where Tz denotes a 1,2,3‐triazole moiety replacing one phenylene ring in the [n]CPP backbone). [ABSTRACT FROM AUTHOR]

Die Funktionalisierung einwandiger Kohlenstoff‐Nanoröhren (SWCNTs) auf eine robuste Weise, die das sp2 Kohlenstoffgerüst nicht beeinträchtigt ist in der aktuellen Forschung eine große Herausforderung. Hier beschreiben wir, wie Triiodidsalze von positiv geladenen Makrozyklen verwendet werden können, um SWCNTs nicht nur von außen, sondern auch gleichzeitig von innen zu funktionalisieren. Wir setzten den Disulfidaustausch in wässrigem Lösungsmittel ein, um den solvophoben Effekt zu maximieren und so einen hohen Grad an Makrozyklus Immobilisierung zu erreichen. Die Charakterisierung mittels Raman‐Spektroskopie, EDX‐STEM und HR‐TEM zeigte deutlich, dass dieses nasschemische Funktionalisierungsprotokoll auch zur Verkapselung von Polyiodidketten im Inneren der Nanoröhren führte. Die resultierenden dreischaligen Kompositmaterialien sind redoxaktiv und weisen ein faszinierendes Zusammenspiel von elektrostatischen, solvophoben und mechanischen Effekten auf, was für Anwendungen in der Energiespeicherung von Interesse sein könnte. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs), hollow cylinders of carbon, hold great promise for advanced technologies, provided their structure remains uniform throughout their length. Their growth takes place at high temperatures across a tube-catalyst interface. Structural defects formed during growth alter CNT properties. These defects are believed to form and heal at the tube-catalyst interface but an understanding of these mechanisms at the atomic-level is lacking. Here we present DeepCNT-22, a machine learning force field (MLFF) to drive molecular dynamics simulations through which we unveil the mechanisms of CNT formation, from nucleation to growth including defect formation and healing. We find the tube-catalyst interface to be highly dynamic, with large fluctuations in the chiral structure of the CNT-edge. This does not support continuous spiral growth as a general mechanism, instead, at these growth conditions, the growing tube edge exhibits significant configurational entropy. We demonstrate that defects form stochastically at the tube-catalyst interface, but under low growth rates and high temperatures, these heal before becoming incorporated in the tube wall, allowing CNTs to grow defect-free to seemingly unlimited lengths. These insights, not readily available through experiments, demonstrate the remarkable power of MLFF-driven simulations and fill long-standing gaps in our understanding of CNT growth mechanisms. There is a lack of atomic level insight on the role of defects on carbon nanotubes' growth. Here, authors present a machine learning force field to drive near-microsecond simulations the entire growth process of this material, unveiling mechanisms of defect formation and healing. [ABSTRACT FROM AUTHOR]

The massive arbitrarily discarded waste of polyethylene terephthalate (PET) bottles become a major environmental pollution source for soils and oceans. Using these waste products to acquire purified water has great significance. We developed a novel strategy of inducing crystallization coupled with solvent exchanging to obtain oriented PET/carbon nanotubes (CNT) foams from waste PET bottles and to fabricate solar interfacial vapor generators (SIVGs). The obtained PET/CNT foams had low densities of 0.18 g/cm3 and high specific strength with compressive stress of 1.8 MPa. The PET/CNT foams generated excellent capillary action that the water delivering rate reached 93.60 kg/m2 h. In addition, the oriented PET foams demonstrated a promising thermal concentration effect that its surface temperature reached 132.8°C. It could evaporate up to 0.82 kg/m2 h under the illumination of 1 sun. Meanwhile, the foams with CNT clusters dispersion also exhibited excellent electrical resistance of 3.57 × 103 Ω m with a low percolation threshold of 0.5 wt.% CNT. This work provides a novel strategy of manufacturing PET SIVG. The key aspect of this work is the significant increase in the surface temperature and the conductivity of PET SIVG compared with other polymer‐based SIVGs, highlighting its novelty and importance. [ABSTRACT FROM AUTHOR]

Carbon nanotube (CNT) polymer composites have broad application prospects in thermal management as electrothermal heaters. Nevertheless, challenge remains in achieving high electrical conductivity for the composites due to the contradiction between CNTs and insulated polymers. To address this issue, herein, innovative use of interface strategy approach by constructing synergistic nanomaterial networks on carboxyl CNTs yarn winding composites for improving the interfacial adhesion and electrical performance. In the work, carboxyl CNTs yarn/CNTs‐graphene oxide (GO) polyvinyl alcohol (PVA) composites (C‐CY‐HP‐C) were proposed and manufactured via filament winding process. The as‐constructed C‐CY‐HP‐C demonstrated a remarkable interfacial shear strength of 2057.16 N mm−1, which was 53.59% higher than that of control CNTs yarn/PVA winding composites. In addition, the C‐CY‐HP‐C achieved an attractive electrical conductivity of 346.39 S cm−1 owing to the electronic transmission channels were formed. Notably, the superior electrical conductivity facilitated a rapid‐response of electrothermal performance for the C‐CY‐HP‐C. It reached a steady‐state temperature of 229.9°C within 10 s when the voltage was 1.2 V. Concurrently, it exhibited an impressive heating rate of 10.8°C min−1 at an ambient temperature of −20°C as the battery surface heater. These findings shed light on the development of technique for battery preheating system based on CNTs yarn/polymer composites. [ABSTRACT FROM AUTHOR]

Silicon oxide (SiOx) anode materials have gained significant attention in lithium-ion batteries due to their high theoretical specific capacity (above 1965 mAh g−1), relatively stable cycling performance, and lower production costs. However, SiOx anode materials tend to form a solid electrolyte interphase (SEI) film and generate inert substances like Li2O and Li4SiO4 during the initial charge and discharge processes, leading to the consumption of active lithium ions and low initial coulombic efficiency. To address these issues effectively, prelithiation of SiOx anode materials is explored in this study. A lithium powder suspension is prepared by dispersing lithium powder and carbon nanotubes (CNTs) in the electrolyte, served as the prelithiation agent. The SiO/G@C@A anode material is then prelithiated with this agent. The lithium powder suspension prelithiation agent enables effective prelithiation of the anode material. The SiO@C@A-1 anode exhibits improved electrochemical performances. At a current density of 0.1 A g−1, the initial specific capacity reaches 981.3 mAh g−1 with an initial coulombic efficiency of 95.65%, which is approximately 25% higher than that of the untreated sample. After 100 cycles and at a current density of 0.5 A g−1, the prelithiated sample retains a discharge specific capacity of 648 mAh g−1, with a capacity retention rate of 83.27%, around 10% higher than that of the untreated sample, demonstrating excellent cycling performances. [ABSTRACT FROM AUTHOR]

As-produced carbon nanotubes contain impurities which can dominate the properties of the material and are thus undesired. Herein we present a multi-step purification treatment that combines the use of steam and hydrochloric acid in an iterative manner. This allows the reduction of the iron content down to 0.2 wt. % in samples of single-walled carbon nanotubes (SWCNTs). Remarkably, Raman spectroscopy analysis reveals that this purification strategy does not introduce structural defects into the SWCNTs' backbone. To complete the study, we also report on a simplified approach for the quantitative assessment of iron using UV-Vis spectroscopy. The amount of metal in SWCNTs is assessed by dissolving in HCl the residue obtained after the complete combustion of the sample. This leads to the creation of hexaaquairon(III) chloride which allows the determination of the amount of iron, from the catalyst, by UV-Vis spectroscopy. The main advantage of the proposed strategy is that it does not require the use of additional complexing agents. [ABSTRACT FROM AUTHOR]

High‐performance bifunctional electrocatalysts for the oxygen reduction (ORR) and oxygen evolution reaction (OER) are essential components in energy conversion and storage technologies. Yet, their poor reversibility hinders their applicability. A highly active ORR/OER catalyst, consisting of multiwalled carbon nanotubes‐supported MnFeNiOx nanoparticles, was subjected to sequences of chronoamperometric steps alternating between the ORR, the OER and highly cathodic potentials (Ec). Rotating ring disk electrode methods revealed that applying Ec leads to a small increase in the current and peroxide species yield during the ORR while enhancing substantially the OER. X‐ray absorption spectroscopy showed irreversible changes in the chemical state of MnFeNiOx correlating with its catalytic properties. The complexity of changes that a composite catalyst may undergo under varying potentials, the importance of monitoring product formation, and the convenience of using dynamic electrochemical sequences for the assessment of catalyst reversibility, as well as for the activation and/or restoration of their catalytic properties, are highlighted. [ABSTRACT FROM AUTHOR]

Effects of carbon nanotubes (CNTs) content and the in situ surface modification via bis(triethoxysilylpropyl) disulfide (Si75) and (3‐aminopropyl) triethoxysilane (KH550) on the rheological properties of rubber nanocomposites are explored. Results from the strain sweep demonstrate that the filler network of the nanocomposite is enhanced when the hydroxylated CNT (HCNT) is incorporated. The promotion of filler–rubber interaction in nanocomposite reinforced with modified CNT is validated by both stress relaxation and strain sweep measurements. The die swell ratio (B) declines with increasing HCNT content and rises with a heightened shear rate. Compared to those without HCNT, B of the nanocomposites, which contained 5 phr HCNT, decreased by 5.4%, 7.0%, and 17.3% at 50, 200, and 500 s−1, respectively. The Si75‐modified HCNT and the carboxylated CNT (CCNT) reduce the B‐value of the extrudates at 500 s−1 by 3.7% and 3.0%, respectively. However, the extrudates filled with KH550‐modified HCNT or CCNT showed a larger B due to pre‐crosslinking, as demonstrated by stress relaxation and swelling tests. Furthermore, it is also found that the application of KH550 has an acceleration effect on the curing reaction, increasing the curing efficiency by 8.5%. Highlights: The promotion of filler–rubber interaction is validated by RPA.The dimensional stability of the composites is improved after incorporating CNT.The extrudates with Si75 exhibit a reduced B and improved surface morphology.CNT content increase raises MH, ML, and shortens the t10 of the composite. [ABSTRACT FROM AUTHOR]

Due to the widespread use of carbon nanotube (CNT)‐reinforced polymers in various industries, investigating the dynamic mechanical response of these materials under impact loading is of significant importance. A three‐dimensional viscoelastic (VE)–viscoplastic (VP) constitutive model for CNT/epoxy nanocomposites is developed. A proper rheological model is established using the generalized Maxwell model to represent the VE behavior and propose an exponential function to express the elasto‐VP response. Employing an empirical logarithmic relationship to estimate material properties at different strain rates, the VP behavior is modeled based on the overstress concept. The 3D numerical discretization of the proposed rate‐dependent material model is also carried out to develop a user‐defined material model (UMAT) for the commercial finite element (FE) software of Abaqus. The performed FE simulations based on the proposed rate‐dependent constitutive material can properly capture stress relaxation and hysteresis behaviors of the nanocomposites. Comparing the estimated tensile and shear stress–strain curves through developed material models with experimental measurements, an excellent agreement is observed. Highlights: Tensile/shear properties of CNT/epoxy are measured at three strain rates.An empirical constitutive model is proposed for any arbitrary strain ratesViscoplastic behavior is captured based on over‐stress conceptA 3D incremental form of a viscoelastic–viscoplastic material model is developed. [ABSTRACT FROM AUTHOR]

Due to the quick growth of portable/wearable devices and electronics, the development of high efficiency flexible electromagnetic interference shielding films is a hot research topic. This work discusses the latest advances in flexible carbon‐based electromagnetic interference shielding films, such as constructing desirable structures, combining with magnetic constituents, and filling with polymer matrices. The new construction strategies, preparation methods, performances, and associated mechanisms are summarized. Moreover, the synergism, multifunctionality, and potential application of outstanding carbon‐based electromagnetic interference shielding films including graphene‐based, CNT‐based, and carbon fiber‐based films are analyzed in detail. Additionally, some significant issues and prospective views on carbon‐based composites as flexible electromagnetic interference shielding films are also presented. Highlights: The latest progress of flexible carbon‐based EMI shielding filmsConstructing desirable structure, synergizing with others, designing CPCsThe relationship between preparation, structure, property, and mechanismsThe synergism, multifunctionality, application of EMI shielding filmsKey challenges and future perspectives of carbon‐based EMI shielding films [ABSTRACT FROM AUTHOR]

This study employs potassium ferrate (K2FeO4) for the oxidation treatment of multi‐walled carbon nanotubes (MWNTs) under neutral and acidic conditions. A wet flash evaporation process is utilized to prepare natural rubber/MWNTs/carbon black composites, enhancing the performance of rubber composites. The increased oxidation level of MWNTs enhances their hydrophilicity, increases the quantity of oxygen‐containing hydroxyl groups on the surface, promotes dispersion within the natural rubber matrix, and ultimately improves the performance of the rubber products. The effective dispersion of MWNTs reduces electron transport resistance, forming a favorable electron transport channel in natural rubber. Experimental results indicate that K2FeO4 achieves the highest oxidation degree and optimal performance in an acidic environment. Compared to untreated MWNTs rubber composites, the oxidized MWNTs rubber composites exhibit a 34.9% reduction in the Payne effect, a 15.7% decrease in wear, a 12.7% reduction in rolling resistance, and a two‐order‐of‐magnitude increase in conductivity. This study provides a novel approach for preparing water‐dispersible MWNTs and high‐performance rubber composites, holding potential applications in premium rubber products and conductive rubber fields. Highlights: The wet flash refining process improved the dispersion of MWNTs.K2FeO4 oxidation of MWNTs was enhanced under acidic conditions.Oxidized MWNTs combined with CB to form a CB‐MWNTs‐CB filler network.Oxidized MWNTs and CB increased the "ball‐chain" arrangement in NR. [ABSTRACT FROM AUTHOR]

Self‐resistance electric (SRE) heating for the curing of carbon fiber reinforced plastic (CFRP) offers the benefits of saving energy consumption and reducing investment in equipment. In this work, the investigation was carried out to illustrate the effect of carbon nanotubes (CNTs) addition (0.5, 1.0, and 1.5 wt%) on the thermoset curing and mechanical properties of carbon fiber‐reinforced epoxy laminates fabricated by SRE heating method. The results show that adding CNTs can improve the temperature uniformity and interlayer‐resin flow during the SRE heating process and have a limited influence on the curing degree of CFRP composites. The tensile strength in the longitudinal direction of the composites increased with the increase of CNT addition. Meanwhile, the flexural strength and interlaminar shear strength had the maximum value with the CNTs content of 0.5 wt% and decreased significantly at the CNTs content of 1.5 wt%. It concludes that the appropriate content of CNTs addition has the potential to improve the thermoset curing performance and mechanical properties of the CFRP laminate composites fabricated by SRE heating. Highlights: This study focuses on the effect of CNT addition on SRE heating for CFRP.The addition of CNTs improved the temperature uniformity during SRE heating.The addition of CNTs can reduce the voids of SRE‐cured CFRP composites.Threshold value of CNTs affected the mechanical performance of SRE‐cured CFRP. [ABSTRACT FROM AUTHOR]

Vitrimers constitute a new class of recyclable thermosets based on the incorporation of associative dynamic covalent bonds, such as disulfide bonds, into the crosslinked matrix. These reversible bonds usually require excess dynamic bonds to confer proper self‐healing and recycling capabilities to the thermoset. In that way, we manufacture epoxy resins cured with 4‐aminophenyl disulfide (AFD) in a stoichiometric ratio, and with 10 and 20 wt% of AFD excesses to analyze the effect of composition on resin properties. Beyond the neat vitrimers analysis, we manufacture nanocomposites doped with carbon nanotubes (CNT) to obtain electroactive vitrimers. These epoxy resins and nanocomposites can be mechanically recycled by milling and hot‐pressing. The recycled nanocomposites conserve partially CNT integrity and dispersion. Even more, recycled nanocomposites with AFD excesses maintain the mechanical strength of the pristine nanocomposites. Vitrimer nanocomposite samples can be also electrically welded, due to their heating by the Joule effect, through a relatively low voltage application, and therefore with low energy consumption, to obtain a monolithic specimen. In summary, the manufactured epoxy vitrimers and nanocomposites are recyclable and sustainable epoxy materials, which can be processed and reprocessed using technologies easily implementable, fast, and with low energy consumption. Highlights: Electroactive and re‐processable vitrimer nanocomposites are manufactured.Nanocomposite vitrimers show conductivities similar to conventional epoxies.Bond exchanging temperatures can be reached by Joule heating.CNT addition enhances disulfide exchanges and thermo‐mechanical recyclability.Electrothermal welding of vitrimer nanocomposites is successfully tested. [ABSTRACT FROM AUTHOR]

Conductive polymer composites (CPCs) have attracted much attention in strain sensing applications due to their excellent conductivities and high sensitivities. However, research on simultaneous modification of CPCs with multiple conductive fillers is lacking. This study aims to systematically investigate the electrical conductivities and strain‐sensing properties of two filler‐modified epoxy resin (EP) composites with different scale additives—short carbon fibers (SCFs) and carbon nanotubes (CNTs)—obtained by mixing and curing to obtain the samples. Both the SCF/EP and SCF/CNT/EP composite resistivities decreased with increasing filler content, and 1.35 wt% was the percolation threshold for SCF/EP composites; during monotonic tensile loading, the resistance change ratio (ΔR/R0) of the CPCs increased with increasing strain, and the sensitivities decreased with increasing conductive filler content. The CPCs containing SCFs and CNTs exhibited stable and repeatable resistance responses during cyclic tensile loading, among which the SCF/CNT_1.5/0.3 composite was the most suitable for use as a sensing material with a sensitivity of 0.149. According to the conductivity and resistance–strain response mechanism analysis, the CNTs supplementing and refining the CPC conductive network composed of SCFs were considered the main reason for the resistance response linearization and excellent dynamic response repeatability. CPCs can be widely used in strain sensing and damage monitoring. Highlights: Provided a strategy for multiscale conductive filler‐modified epoxy resins.Realized monotonicity of resistance–strain response by adding multiscale conductive fillers.Explored resistance‐strain effect under dynamic cycling loading.Identified optimal materials for damage detection.Analyzed the resistance–strain response mechanism of single and multiscale conductive filler‐modified CPCs. [ABSTRACT FROM AUTHOR]

Chemical vapor deposition (CVD) method was performed to grow carbon nanotubes (CNTs) on oxidized carbon fiber (CF). First, CF was oxidized by a simple and gentle way to increase the number of active groups and the optimal treatment time was determined. Then, effects of catalyst concentration and growth time on morphologies and loading amount of CNTs, the properties of CF/CNTs reinforcements, and the interlayer properties of CF/CNTs composites were explored. When the catalyst concentration and growth time were controlled at a reasonable level, CNTs can be uniformly grown on the CF surface. The interlaminar shear strength (ILSS) was characterized and the fracture surfaces of CF/CNTs composites were observed. The results demonstrated that when the catalyst precursor was kept at 0.05 mol/L and the growth time was controlled at 10 min, CNTs had the best strength effect and the ILSS increased by 30.25% compared to that of composites without CNTs. The fracture surface showed that CNTs can penetrate the matrix at the interface and enhance the interface through mechanical interlocking effect. The CNTs‐induced interphase allows the stress inside the composites to propagate continuously between resin and fibers, thereby heightening the load carrying capacity. Highlights: A simple and gentle way was performed to activate CF without strength reduction.The influence mechanism of various parameters was revealed in detail.The mechanism of CNTs enhancing the interface was revealed. [ABSTRACT FROM AUTHOR]

A fractional technique is used to evaluate the temperature, mass, and velocity flow of single and double wall CNTs over a vertical plate. Slip boundary conditions and applied magnetic force are addressed. Human blood is used to examine how base fluid behaves. Applying the proper dimensionless variables results in the dimensionless formulation of initial and boundary conditions related to the governed dimensional concentration, momentum, and energy equations. The Laplace transform technique is used to resolve the dimensionless governing partial differential equations and get the solutions. The constant proportional Caputo (CPC) time-fractional derivative is a unique class of fractional model used in the simulation technique. The fundamental definitions are used to support the said model first. Using MWCNTs and SWCNTs in comparison to the flow characteristics, a thermal and mass study is given. The heat and mass transfer processes for single-walled carbon nanotubes (SWCNTs) have been shown to typically be progressive. The momentum profile decreases as the fractional variables rise. Multi-walled carbon nanotubes (MWCNTs) show more progressive velocity control as a result of the magnetic parameter. Graphs demonstrate the influence of embedding factors on the velocity, energy, and concentration profiles. [ABSTRACT FROM AUTHOR]

Advancements in fabrication technologies have led to the possibility of synthesizing atomic-scale graphene nanoribbon (GNR) and carbon nanotube (CNT) based nanodevices. The purpose of this study was to model the electronic properties and electrical characteristics of these devices by atomistic modeling using density functional theory and the non-equilibrium Green's function and compare the effects of molecular functionalization and sensing. The potential profile of the device was computed using the three-dimensional Poisson equation for smaller applied bias within one voltage range. Simulations showed a bandgap of 1 eV for armchair GNRs (AGNRs), which were insensitive to functionalized amine molecules, resulting in fewer alterations in the density of states (DoS), transmission spectra and the device current (Δ I). The bandgap further increased to 2 eV upon rolling the GNR into a armchair CNT (ACNT), which further decreased sensitivity. However, changing the configuration of the AGNR to a zigzag GNR (ZGNR) led to remarkable changes in the DoS and transmission spectra and a significant improvement in sensitivity. This improvement increased by 1.5–2 times upon rolling the ZGNR into a zigzag CNT (ZCNT). Thus, at lower dimensions in atomic scale, we found an alteration in device current of the carbon structures that was directly proportional to sensitivity in the following order: Δ I ACNT < Δ I AGNR < Δ I ZGNR < Δ I ZCNT. However, the same was found to fall for ZGNR and ZCNT with an increase in width to length (W / L) ratio. This highlights the importance of smaller atomic structures and this work provides a guideline for effective utilization of these structures for biochemical sensing. [ABSTRACT FROM AUTHOR]

Silicone rubber (SR) has excellent properties, such as high and low temperature resistance and weather resistance. However, the flame retardancy of SR is rather poor, which severely limits the range of application of SR. Therefore, it is necessary to make certain modifications in order to improve its flame retardancy. In this study, wollastonite, low‐melting glass powder, and phytate‐modified carbon nanotubes (CPCC) were added to SR to prepare ceramizable silicone rubber (CSR) composites with good fire safety performance. The effect of CPCC on the flame retardancy and ceramization properties of CSR materials was investigated. The results showed that, with the addition of 3 phr of CPCC, the limiting oxygen index of the CSR composite material reached 33.8%, which was 26.1% higher than that of pure SR, and its UL‐94 grade reached V‐0 grade. The results of the cone calorimeter test showed that the total heat release of the CSR composite with three parts CPCC was reduced by 26.6%, and the peak heat release rate reduced by 13.1%. In addition, after the CSR6 composite was calcined at 1000°C for 1 h, the ceramic body formed by the composite had good supporting properties, and its bending strength was as high as 6.17 MPa. [ABSTRACT FROM AUTHOR]

Facing increasing electromagnetic radiation pollution, soft sensors with electromagnetic interference (EMI) shielding is highly desirable. Here, flexible electromagnetic shielding [polyacrylonitrile/Fe3O4/polyaniline]//[multiwalled carbon nanotube/polyvinyl pyrrolidone] (denoted [PAN/Fe3O4/PANI]//[MWCNT/PVP]) Janus membrane is reported for pressure and sliding sensing. The [PAN/Fe3O4/PANI] layer of Janus membrane as the force and sliding sensing unit can generate direct current‐type (DC‐type) voltage signals by conducting polymer/metal Schottky junction, whereas [MWCNT/PVP] layer serves as main electromagnetic shielding unit. Under the vertical force and horizontal sliding of aluminum (Al) foil, it can output DC‐type voltage signals based on the Schottky contact. The performance of [PAN/Fe3O4/PANI]//[MWCNT/PVP] Janus membrane for pressure and sliding sensing is appropriately explored and assessed. Moreover, the Janus membrane exhibits excellent shielding effects with average EMI shielding effectiveness (SE) of 37.54 dB in 8.2–12.4 GHz (X‐Band) frequency ranges. Thus, based on the asymmetrical double‐layer structure, soft DC‐type sensor with EMI shielding is achieved, showing utilization potential in wearable electronics and intelligent robots. [ABSTRACT FROM AUTHOR]

Highlights A sizing agent mainly consisting of polyethersulfone and acidified multi‐walled carbon nanotubes (MWCNT) was developed for surface modification of carbon fibers (CF) to enhance the interfacial bond and to form carbon fiber‐carbon nanotube (CF‐MWCNT) multiscale reinforcements. To prepare the modified carbon fiber/epoxy resin composites (CFRP), a vacuum molding technique was used in this study. The effects of the MWCNT‐containing sizing agent on the morphology and chemical structure of the CF surface were observed by scanning electron microscopy and Fourier transform infrared spectroscopy. The influence of MWCNT length and content on the mechanical properties of CFRP were also studied. The experimental results showed that the strength of the CFRP decreased with the increase of MWCNT length, and the MWCNT with a content of 0.05 wt% had a good reinforced effect on the CFRP. After the sizing treatment, the interlaminar shear strength (ILSS) of the CFRP is increased. These enhancements are attributed to the improved mechanical bonding and chemical bonding between CF and resin matrix. The MWCNT provides nanosized rough surface to CF and these acidified MWCNTs attached to the surface of CF with polar oxygen‐containing functional groups improve the compatibility with reinforcement and resin matrix. Carbon fiber was modified by a sizing agent mainly consisting of polyethersulfone and acidified carbon nanotube (CNT). CNTs enhance the interfacial chemical bonding and mechanical bonding. The CNT length affects the mechanical properties of the carbon fiber/epoxy resin composites (CFRP). The modified carbon fiber has enhanced the mechanical properties of the CFRP. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotubes (SWCNTs) show great potential for their application as cancer therapeutic nanodrugs, but the efficiency and mechanism of their accumulation in the cell, the modulation of cell activity, and the strong dependence of the results on the type of capping molecule still hinder the transfer of SWCNTs to the clinic. In the present study, we determined the mechanism and sequence of accumulation, distribution and type discrimination of SWCNTs in glioma cells by applying K-means clustering and principal component analysis (PCA) of Raman spectra of cells exposed to SWCNTs capped with either DNA or oligonucleotides (ON). Based on the specific biochemical information uncovered by PCA and further applied to K-means, we show that the accumulation of SWCNT–DNA occurs in two phases. The first phase involves the transport of SWCNT–DNA through vesicles and its redistribution in the cytoplasm, which is reflected in two SWCNT-related clusters. The second phase begins after 18 hours of interaction between cells and SWCNT–DNA. PCA shows the appearance of two SWCNT-associated PC loadings, reflected by the addition of a new cluster of SWCNTs with a narrowed and shifted G-peak in the spectra. It is caused by the loss of DNA capping and clumping of SWCNTs and triggered by the acidic conditions in autolysosomes resulting from the fusion of transport vesicles with lysosomes. SWCNTs penetrate all cellular compartments after 42–66 hours and lead to cell death. The clumped SWCNTs are released to the outside. In contrast, SWCNT–ON is hardly accumulated in glioma cells and after 72 hours of exposure to SWCNT–ON, the accumulation of SWCNTs corresponds to the first stage without reaching the second. PCA made it possible to separate the characteristics of cellular components against the high-intensity Raman signal from nanotubes and, thus, to propose the mechanism of accumulation and metabolism of nanomaterials in living cells without the use of additional research approaches. Our results elucidate the time dependence of the accumulation of SWCNTs on the capping molecule. We expect that our results can make an important contribution to the use of these nanomaterials in the clinic. [ABSTRACT FROM AUTHOR]

This article explores the use of copper foam modified with cobalt phthalocyanine carbon nanotube hybrids to improve the selectivity and stability of the CO2 reduction reaction (CO2RR) in a flow cell setup. The CO2RR is a promising method for converting carbon dioxide into useful industrial molecules, and renewable energy sources are of interest for this reaction. Copper is known for its ability to produce C2+ products from CO2RR, but low selectivity and hydrogen evolution reaction (HER) can limit its effectiveness. The incorporation of cobalt phthalocyanine hybrids with carbon-based materials enhances stability, selectivity, and conductivity. The study demonstrates the ability to regulate HER and improve CO2RR activity on copper foam through non-covalent surface modification with cobalt phthalocyanine hybrids. The modified copper foam exhibits a ten-fold increase in CO formation and remains stable over time. The article discusses the successful combination of cobalt phthalocyanine hybrids and carbon nanotubes through axial coordination of carboxylic groups. The CO2RR performance of the modified copper foam electrodes is examined, and the cobalt phthalocyanine hybrid outperforms other electrodes in terms of CO2RR product formation. The long-term stability of the cobalt phthalocyanine hybrid is also demonstrated. [Extracted from the article]

In this paper, a series of iron oxide/reduced graphene oxide/carbon nanotube composites (K3‐Fe2O3‐rGO/CNT) with well‐dispersedFe2O3 particles are prepared by in situ reaction and then heat‐treatment, and its electrochemical and battery performancesare studied as the anode material of lithium‐ion batteries. The results show that the introduction of reduced graphene oxide/carbon nanotube (rGO/CNT) improves the electrochemical and battery performances of the prepared electrode material. In particular, the K3‐Fe2O3‐rGO/CNT (30 %) composite material has a reversible capacity of 1559 mAh g−1 after 100 charge/discharge cycles at 100 mA g−1. And its specific discharge capacityis 641.1, 639.7, 609.5, 578.6 and 543 mAh g−1at the current density of 100, 200, 500, 1000 and 2000 mA g−1, respectively,with 84.7 % of capacity retention even with a 10 times increase in current density. The research of charge storage indicates that the electrochemical process is a mixed control process of diffusion and capacitance. The improved electrochemical and battery performancesfor the composite electrode material can be attributed to the enhanced dispersion of the Fe2O3 and the enhanced conductive network provided by rGO/CNT composite carbon. It makes a promising way to prepare high performance of anode material for lithium‐ion battery. [ABSTRACT FROM AUTHOR]

We present the first work of the synthesis mechanism from graphene quantum dots (GQDs) to carbon nanotubes (CNTs) by an ion-sputtering assisted chemical vapor deposition. During the annealing process, a Pt thin film deposited by the ion-sputtering was dewetted and agglomerated to form many nanometer-sized particles, leading to Pt nanoparticles (PtNPs) that can act as catalysts for creating carbon allotropes. The shape of the allotropes can be effectively tailored from GQDs to CNTs by controlling three key parameters such as the dose of catalytic ions (D), amounts of carbon source (S), and thermal energy (T). In our work, it was clearly proved that the growth control from GQDs to CNTs has a comparably proportional relationship with D and S, but has a reverse proportional relationship with T. Furthermore, high-purity GQDs without any other by-products and the CNTs with the cap of PtNPs were generated. Their shapes were appropriately controlled, respectively, based on the established synthesis mechanism. [ABSTRACT FROM AUTHOR]

Solar‐driven steam generation membranes have garnered increasing attention for freshwater production. Nonetheless, the adverse impact of salt accumulation on membrane surfaces directly undermines the efficacy of solar evaporation. In this work, one type of composite membrane comprised of carbon nanotubes (CNTs)‐styrene‐ethylene‐butadiene‐styrene (SEBS) was fabricated by modified vapor phase pore‐forming technique. Through the grafting of maleic anhydride (MAH), the CNTs‐SEBS‐MAH composite membrane was successfully hydrolyzed. As a consequence, the composite membrane exhibits evaporation rate as high as 1.28 kg m−2 h−1 under one sun solar irradiation, accompanied by an outstanding solar vapor conversion efficiency of 87.5%. In addition, the fabricated composite membrane has high resistance to salt accumulation, as well as self‐cleaning capability. This work provides a route for manufacturing hydrophilic polymer composite membrane towards solar energy driven seawater desalination. [ABSTRACT FROM AUTHOR]

With the growing complexity of separation systems, the application of thin film composite nanofiltration (TFN) membranes in organic solvent separation faces numerous challenges. To augment its solvent stability, an in‐situ constructed dopamine hydrogel doped with UiO‐66@CNT was developed as an intermediate layer on a polyetherimide (PEI) ultrafiltration membrane. Subsequent interfacial polymerization on this interlayer led to the formation of a solvent‐resistant nanofiltration membrane with a vast covalent bond structure, large specific surface area, and enhanced hydrophilicity. Our findings revealed that when the CNT loading in the UiO‐66@CNT composite nanoparticles was 2 wt%, the TFN‐U2C2 membrane exhibited a maximum pure water flux of 126.32 L/(m2·h) and a methanol flux of 45.45 L/(m2·h). The rejection rates for Congo red aqueous and methanol solutions were 96.88% and 92.14%, respectively. The membrane also demonstrated commendable anti‐fouling properties. Remarkably, even after 48 h of immersion in various organic solvents, the membrane retained its morphology and separation efficiency. Compared to the TFN‐U2 membrane without CNT addition, the enhancement in separation performance was considerably significant. Hence, this membrane has significant potential for application in treatment of wastewater containing organic solvents and is promising in related fields. [ABSTRACT FROM AUTHOR]

The thermoelectric properties of inhomogeneous BCN alloy nanotubes are investigated using a first-principles approach and the non-equilibrium Green's function method based on virtual crystal approximation. The asymmetric distribution of B, C, and N atoms in these nanotubes causes tilted transmission probabilities around the Fermi level, disrupting electron–hole symmetry under varying temperature gradients. Consequently, the thermal charge currents exhibit fascinating behaviors like negative differential thermal resistance and thermoelectric current switching. Reducing the carbon concentration leads to decreased electrical conductance, electronic thermal conductance and Lorenz number but increased Seebeck coefficient and figure of merit. This emphasizes the significance of carbon concentration in tuning the thermoelectric efficiency of these nanotubes, suggesting a possibility for tailored thermoelectric nanomaterial design. [ABSTRACT FROM AUTHOR]

In this study, Polyethyleneimine (PEI) was utilized to modulate the electronegativity of carbon nanotubes (CNTs) through a mild method to promote its electrocatalytic performance for electrosynthesis of H2O2. The characterization results indicate the co-doping of oxygen and nitrogen elements and the CNTs-80 (modification temperature was 80 °C) catalyst exhibited the highest content of nitrogen (4.05%) and OII functional groups (73.5%). Accordingly, the GF/CNTs-80/PTFE cathode exhibited the highest H2O2 yield of 116.34 mg L−1 at pH 7, suggesting that the introduction of nitrogen and oxygen-containing functional groups (carboxyl and ether groups) effectively enhances its 2e− ORR performance. Furthermore, a more positive surface potential and reduced diffusion resistance were conducive to the electrochemical generation of H2O2. This research contributes to the understanding of surface potential modulation and highlights the potential of PEI-modified CNTs cathodes for efficient H2O2 electrogeneration. Highlights: PEI-modified CNTs catalysts for electrochemical production of H2O2 were synthesized. The introduction of O-containing functional groups enhanced the catalytic activity of the composite cathode. The positive surface potential enhanced the catalytic activity of the composite cathode. The GF/CNTs-80/PTFE composite cathode achieved the highest H2O2 yield of 116.34 mg·L−1at pH 7. [ABSTRACT FROM AUTHOR]

Hybrid nanozyme graphene quantum dots (GQDs) deposited TiO2 nanotubes (NTs) on titanium foil (Ti/TiO2 NTs-GQDs) were manufactured by bestowing the hybrid with the advantageous porous morphology, surface valence states, high surface area, and copious active sites. The peroxidase-like activity was investigated through the catalytic oxidation of chromogenic substrate 3,3′,5,5′-tetramethylbenzidine (TMB) in the presence of H2O2, which can be visualized by the eyes. TiO2 NTs and GQDs comprising oxygen-containing functional groups can oxidize TMB in the presence of H2O2 by mimicking peroxidase enzymes. The peroxidase-mimicking activity of hybrid nanozyme was significantly escalated by introducing light illumination due to the photosensitive features of the hybrid material. The peroxidase-like activity of Ti/TiO2 NTs-GQDs enabled H2O2 determination over the linear range of 7 to 250 μM, with a LOD of 2.1 µM. The satisfying peroxidase activity is possibly due to the unimpeded access of H2O2 to the catalyst's active sites. The porous morphology provides the easy channeling of reactants and products. The periodic structure of the material also gave rise to acceptable reproducibility. Without material functionalization, the Ti/TiO2 NTs-GQDs can be a promising substitute for peroxidases for H2O2 detection. [ABSTRACT FROM AUTHOR]

A core–shell ZIF-67@ZIF-8-derived Co nanoparticles embedded in N-doped carbon nanotube polyhedra (Co/C-NCNP) hybrid nanostructure was prepared by a pyrolysis method. The synthesized Co/C-NCNP was modified on the screen-printed carbon electrode and used for the portable wireless sensitive determination of breviscapine (BVC) by differential pulse voltammetry. The Co/C-NCNP had a large surface area and excellent catalytic activity with increasing Co sites to combine with BVC for selective determination, which led to the improvement of the sensitivity of the electrochemical sensor. Under optimized conditions, the constructed sensor had linear ranges from 0.15 to 20.0 µmol/L and 20.0 to 100.0 µmol/L with the limit of detection of 0.014 µmol/L (3S0/S). The sensor was successfully applied to BVC tablet sample analysis with satisfactory results. This work provided the potential applications of zeolitic imidazolate framework-derived nanomaterials in the fabrication of electrochemical sensors for the sensitive detection of drug samples. [ABSTRACT FROM AUTHOR]

Context: CO2 and CO gas sensors are very important to recognize the insulation situation of electrical tools. ToCO explore the application of noble metal doped of aluminum nitride nanotubes for gas sensors, DFT computations according to the first principal theory were applied to study sensitivity, adsorption attributes, and electronic manner. In this investigation, platinum-doped aluminum nitride nanotubes were offered for the first time to analyze the adsorption towards CO2 and CO gases. Firm construction of platinum-doped aluminum nitride nanotubes (Pt-AlNNT) was investigated in four feasible places, and the binding energy of firm construction is 1.314 eV. Respectively, the adsorption energy between the CO2 and Pt-AlNNT systems was − 2.107 eV, while for instance of CO, the adsorption energy was − 3.258 eV. The mentioned analysis and computations are considerable for studying Pt-AlNNT as a new CO2 and CO gas sensor for electrical tools insulation. The current study revealed that the Pt-AlNNT possesses high selectivity and sensitivity towards CO2 and CO. Methods: In this research, Pt-doped AlNNT (Pt-AlNNT) has been studied as sensing materials of CO and CO2 for the first time. The adsorption process of Pt-AlNNT has been computed and analyzed through the DFT approach. DFT computations by using B3LYP functional and 6–31 + G* basis sets have been applied in the GAMESS code for sensing attributes, which contribute to potential applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Over the years, reducing friction and wear-induced deformation, damage and/or removal of material at various contact interfaces has always aroused significant interests due to the substantial benefits for impaired machinery components, as well as the efficiencies in energy and economy. Among numerous advanced nanomaterials, carbon nanotubes (CNTs) have been recognized as solid lubricants, or additives in the liquid/solid material systems (coatings, composites and lubricants) to effectively reduce friction and wear. This is well-motivated by CNTs' hollow tubular nanostructure and outstanding physicochemical properties which can potentially support them with many favorable frictional mechanisms, such as filling/mending effect, sliding/rolling effect, and tribofilm-forming effect. Despite the enormous efforts pertaining to CNTs for tribological optimizations, discussing them across the nano-scale to macro-scale for the understanding of critical interactions between the CNTs and contact objects remains rarely explored. In this review, the state-of-the-art advances in computational tribology research of the CNTs and their significant nano/macro-tribology mechanisms in related systems are methodically provided, beginning with a brief overview of CNTs on their manufacturing, structural properties, and functionalization. Additionally, we present a condensed summary of the encouraging findings, accompanied by some valuable recommendations for the sustaining prosperity of CNTs in tribology. [ABSTRACT FROM AUTHOR]

Sorting single‐walled carbon nanotubes (SWNTs) that are heterogeneous into homogeneous groups based on their electronic type, chirality, and handedness is crucial for optoelectronic and biological applications. To achieve this, researchers have utilized dispersants with different binding affinities to sort SWNTs according to their chiralities. This review article provides an overview of the methods developed for sorting SWNTs using dispersants, with a particular focus on the role played by dispersant binding affinities. The article is organized into six sections, including an introduction, a background on SWNTs and dispersant‐based individualization of SWNTs, information on dispersants and their binding affinities, separation methods for SWNTs based on controlling the dispersant binding affinity, parameters used to control dispersant binding affinity, and a conclusion. It is hoped that this review will enhance understanding of the intricate interactions between dispersants and SWNTs, leading to the development of new SWNT sorting methods for future applications. [ABSTRACT FROM AUTHOR]

Phenol-formaldehyde foams are lightweight polymer composites that are prepared by foaming the resin. The major goal is to reduce the weight of the composite significantly while increasing thermal stability and sorption behaviour.This paper gives information about the characteristics of the reinforced PF foams with (CNT/CNT-IL) by FT-IR spectrum, SEM images, and investigations on the thermal properties by TGA/DSC analysis. BET was used as a tool for porosity analysis and oil sorption of the foams is also investigated. According to the TGA data, adding nano-silica and CNT/CNT-IL to PF foams improves thermal stability. The sorption experiments for unmodified and modified foams with nano-silica, and CNT/CNT-IL reveal that increasing the nanofiller content results in higher sorption capacities. [ABSTRACT FROM AUTHOR]

Titanium dioxide (TiO2) is the material of choice for photocatalytic and electrochemical applications owing to its outstanding physicochemical properties. However, its wide bandgap and relatively low conductivity limit its practical application. Modifying TiO2 with carbon species is a promising route to overcome these intrinsic complexities. In this work, we propose a facile method to modify TiO2 nanotubes (NTs) based on the remnant organic electrolyte retained inside the nanotubes after the anodization process, that is, without removing it by immersion in ethanol. Carbon‐modified TiO2 NTs (C‐TiO2 NTs) showed enhanced H2 evolution in photocatalysis under UV illumination in aqueous solutions. When the C‐TiO2 NTs were subjected to UV light illumination, the carbon underwent modification, resulting in higher measured photocurrents in the tube layers. After UV illumination, the IPCE of the C‐TiO2 NTs was 4.4‐fold higher than that of the carbon‐free TiO2 NTs. [ABSTRACT FROM AUTHOR]

Composite polymer materials have high strength and lightness, which makes them attractive for use in a variety of structures and products. The present article contains an overview of modern works devoted to the production of composite materials based on poly(methyl methacrylate) (PMMA) with improved characteristics. The possibility of obtaining such materials can be a key area for creating more efficient and durable products in various industries. Various methods were considered to improve the characteristics of PMMA by doping the polymer matrix with carbon nanotubes (CNTs), graphite, nanohydroxyapatite particles, micro-zirconia nanoparticles, titanium dioxide, etc. The possibilities of using the obtained composite materials in various industries such as aviation, automotive, construction, medical and others are discussed. This article also presents the results of our own research on the mechanisms of interaction of PMMA with single-layer CNTs, leading to the creation of a composite polymer system "PMMA+CNT", achieved using the modern quantum chemical method DFT. This article presents a review of the recent research on the effect of CNTs on the mechanical and electrically conductive properties of nanocomposite materials. The outcomes of this study can be important for the development of science and technology in various fields, from fundamental chemistry to applied scientific research. [ABSTRACT FROM AUTHOR]

As power sources for Internet-of-Things sensors, thermoelectric generators must exhibit compactness, flexibility, and low manufacturing costs. Stretchable and flexible painted thermoelectric generators were fabricated on Japanese paper using inks with dispersed p- and n-type single-walled carbon nanotubes (SWCNTs). The p- and n-type SWCNT inks were dispersed using the anionic surfactant of sodium dodecylbenzene sulfonate and the cationic surfactant of dimethyldioctadecylammonium chloride, respectively. The bundle diameters of the p- and n-type SWCNT layers painted on Japanese paper differed significantly; however, the crystallinities of both types of layers were almost the same. The thermoelectric properties of both types of layers exhibited mostly the same values at 30 °C; however, the properties, particularly the electrical conductivity, of the n-type layer increased linearly, and of the p-type layer decreased as the temperature increased. The p- and n-type SWCNT inks were used to paint striped patterns on Japanese paper. By folding at the boundaries of the patterns, painted generators can shrink and expand, even on curved surfaces. The painted generator (length: 145 mm, height: 13 mm) exhibited an output voltage of 10.4 mV and a maximum power of 0.21 μW with a temperature difference of 64 K at 120 °C on the hot side. [ABSTRACT FROM AUTHOR]

Utilizing hydrogen as a viable substitute for fossil fuels requires the exploration of hydrogen storage materials with high capacity, high quality, and effective reversibility at room temperature. In this study, the stability and capacity for hydrogen storage in the Sc-modified C3N4 nanotube are thoroughly examined through the application of density functional theory (DFT). Our finding indicates that a strong coupling between the Sc-3d orbitals and N-2p orbitals stabilizes the Sc-modified C3N4 nanotube at a high temperature (500 K), and the high migration barrier (5.10 eV) between adjacent Sc atoms prevents the creation of metal clusters. Particularly, it has been found that each Sc-modified C3N4 nanotube is capable of adsorbing up to nine H2 molecules, and the gravimetric hydrogen storage density is calculated to be 7.29 wt%. It reveals an average adsorption energy of −0.20 eV, with an estimated average desorption temperature of 258 K. This shows that a Sc-modified C3N4 nanotube can store hydrogen at low temperatures and harness it at room temperature, which will reduce energy consumption and protect the system from high desorption temperatures. Moreover, charge donation and reverse transfer from the Sc-3d orbital to the H-1s orbital suggest the presence of the Kubas effect between the Sc-modified C3N4 nanotube and H2 molecules. We draw the conclusion that a Sc-modified C3N4 nanotube exhibits exceptional potential as a stable and efficient hydrogen storage substrate. [ABSTRACT FROM AUTHOR]

The paper proposes a quantitative description of the emission properties of fibrous conductive materials (graphite with carbon nanotubes) under the intense electric field. These materials are used as cold cathodes in electronic devices; they have a significant effect on the electrical strength of vacuum and gas-filled gaps. The emission current density is theoretically evaluated for cathodes made of carbon nanofiber and those with stochastic parameters of the surface texture. It is shown that the stochastic nanotexture provides the enhanced current emission as compared to that yielded from the theory of the Fowler–Nordheim tunneling process at the similar conditions of the localized enhancement of the external electric field. [ABSTRACT FROM AUTHOR]

Buckypaper (BP), a flexible and porous material, exhibits photovoltaic properties when exposed to light. In this study, we employed radio frequency (RF) sputtering of zinc oxide (ZnO) followed by rapid thermal annealing to enhance the photovoltaic response of BP. We investigated the impact of various sputtering parameters, such as the gas flow ratio of argon to oxygen and deposition time, on the morphology, composition, resistivity, and photovoltaic characteristics of ZnO-modified BP. Additionally, the photovoltaic performance of the samples under different illumination modes and wavelengths was compared. It was found that optimal sputtering conditions—argon to oxygen flow ratio of 1:2, deposition time of 20 min, and power of 100 watts—resulted in a ZnO film thickness of approximately 45 nanometers. After annealing at 400 °C for 10 min, the ZnO-modified BP demonstrated a significant increase in photocurrent and photovoltage, along with a reduction in resistivity, compared to unmodified BP. Moreover, under gradient illumination, the ZnO-modified BP exhibited a photovoltage enhancement of 14.70-fold and a photocurrent increase of 13.86-fold, compared to uniform illumination. Under blue light, it showed a higher photovoltaic response than under other colors. The enhancement in photovoltaic response is attributed to the formation of a Schottky junction between ZnO and BP, an increased carrier concentration gradient, and an expanded light absorption spectrum. Our results validate that ZnO sputtering followed by annealing is an effective method for modifying BP for photovoltaic applications such as solar cells and photodetectors. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) are well known for their outstanding field emission (FE) performance, facilitated by their unique combination of electrical, mechanical, and thermal properties. However, if the substrate of choice is a poor conductor, the electron supply towards the CNTs can be limited, restricting the FE current. Furthermore, ineffective heat dissipation can lead to emitter–substrate bond degradation, shortening the field emitters' lifetime. Herein, temperature-stable titanium nitride (TiN) was deposited by plasma-enhanced atomic layer deposition (PEALD) on different substrate types prior to the CNT growth. A turn-on field reduction of up to 59% was found for the emitters that were generated on TiN-coated bulk substrates instead of on pristine ones. This observation was attributed exclusively to the TiN layer as no significant change in the emitter morphology could be identified. The fabrication route and, consequently, improved FE properties were transferred from bulk substrates to free-standing, electrically insulating nanomembranes. Moreover, 3D-printed, polymeric microstructures were overcoated by atomic layer deposition (ALD) employing its high conformality. The results of our approach by combining ALD with CNT growth could assist the future fabrication of highly efficient field emitters on 3D scaffold structures regardless of the substrate material. [ABSTRACT FROM AUTHOR]

Electrodes are one of the key components that influence the performance of all-vanadium redox flow batteries (VRFBs). A porous graphite felt with modified fiber surfaces that can provide a high specific activation surface is preferred as the electrode of a VRFB. In this study, a simple binder-free approach is developed for preparing stable carbon nanotube modified graphite felt electrodes (CNT-GFs). Heat-treated graphite felt electrodes (H-GFs) are dip-coated using CNT homogeneous solution. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) results conclude that CNT-GFs have less resistance, better reaction currents, and reversibility as compared to H-GF. Cell performances showed that CNT-GFs significantly improve the performance of a VRFB, especially for the CNT-GF served in the positive side of the VRFB. CNT presence increases the electrochemical properties of the graphite electrode; as a result, reaction kinetics for both VO2+/VO2+ and V3+/V2+ are improved. Positive CNT-GF (P-CNT-GF) configured VRFB exhibits voltage efficiency, coulombic efficiency, and energy efficiency of 85%, 97%, and 82%, respectively, at the operating current density of 100 mA cm−2. At high current density of 200 mA cm−2, the VRFB with P-CNT-GF shows 73%, 98%, and 72% of the voltage, coulombic, and energy efficiencies, respectively. The energy efficiency of the CNT-GF is 6% higher when compared with that of B-H-GF. The VRFB with CNT-GF can provide stable performance for 300 cycles at 200 mA cm−2. [ABSTRACT FROM AUTHOR]

This article presents, for the first time, a comparative analysis of the emission characteristics of large-area field-effect cathodes (LAFE) based on carbon nanotubes (CNTs) of various morphologies according to key parameters using a unique computerized technique. The work presents a description of a technology for creating various CNT arrays and their comprehensive structure characterization. All CNT arrays synthesized by the catalytic PECVD method on a silicon substrate showed a high degree of chemical purity under the presented technological conditions. In some cases, nanoisland films of Fe were used as a catalyst; in others, thin films of NiO were used, which were deposited on a silicon wafer by chemical vapor deposition (CVD) and atomic layer deposition (ALD), respectively. As a result of these studies, it turned out that an array with a thick CNT coating has good resistance to the action of strong electric fields, fairly good uniformity of distribution of emission centers, a fairly high selection current (2.88 mA/cm2 at 4.53 V/μm), and compliance with the normal current mode according to the "orthodox" test, which makes the morphology of such structures the most promising for further technological optimization of CNT-based cathodes for various practical applications. [ABSTRACT FROM AUTHOR]

As a smart implant, magnesium (Mg) is highly biocompatible and non-toxic. In addition, the elastic modulus of Mg relative to other biodegradable metals (iron and zinc) is close to the elastic modulus of natural bone, making Mg an attractive alternative to hard tissues. However, high corrosion rates and low strength under load relative to bone are some challenges for the widespread use of Mg in orthopedics. Composite fabrication has proven to be an excellent way to improve the mechanical performance and corrosion control of Mg. As a result, their composites emerge as an innovative biodegradable material. Carbon nanotubes (CNTs) have superb properties like low density, high tensile strength, high strength-to-volume ratio, high thermal conductivity, and relatively good antibacterial properties. Therefore, using CNTs as reinforcements for the Mg matrix has been proposed as an essential option. However, the lack of understanding of the mechanisms of effectiveness in mechanical, corrosion, antibacterial, and cellular fields through the presence of CNTs as Mg matrix reinforcements is a challenge for their application. This review focuses on recent findings on Mg/CNT composites fabricated for biological applications. The literature mentions effective mechanisms for mechanical, corrosion, antimicrobial, and cellular domains with the presence of CNTs as reinforcements for Mg-based nanobiocomposites. [ABSTRACT FROM AUTHOR]

The incorporation of a "graphene-carbon nanotube-graphene" structure as a filler in polyimide composites to enhance their mechanical and thermal properties was investigated. The performance of the composites was evaluated by molecular dynamics simulations. Findings revealed that this arrangement significantly enhanced the mechanical strength and stiffness of the composites, improving their tensile and shear properties. [ABSTRACT FROM AUTHOR]

Large amplitude vibrations are inevitable in the life cycle of a composite structure. On the other hand, the large amplitude deflections may give rise to cracks and fractures in the composite structure. Consequently, in order to avoid such issues, in this study, the examination of nonlinear events including bifurcation analysis of a beam structure made of advanced materials exposed to superharmonic excitation is presented, for the first time. In this regard, an unshearable model is developed for an aggregated carbon nanotube-strengthened beam in line with the Eshelby–Mori–Tanaka hypothesis. Making use of the advantage of the direct method of multiple scales, the reduced order equations for the aggregated nanocomposite beam subjected to primary, and superharmonic excitations are disclosed. Some fascinating numerical simulations clarify nonlinear aspects of the aggregated beam under the alterations of agglomeration parameters as well as temperature. It is deduced that the increment of heterogeneity enlarges the maximum quantity of the steady-state response until, two more steady-state responses are generated. Thereafter, the heterogeneity increment reduces the gap between the two stable steady-state responses. After a catastrophic bifurcation, one stable steady-state response remains. The amplitude of the remained steady state response decreases as a consequence of the heterogeneity increment. The aggregation decreases the temperature at which the multi-valued steady-state response zone starts, when the nanocomposite beam is superharmonically excited. Moreover, the heterogeneity doesn't change the maximum steady-state amplitude of the nanocomposite beam undergone superharmonic excitation at a given force frequency. On the other hand, the gap between the two steady state amplitudes of the nanocomposite beam subjected to primary resonance excitation extends as a consequence of the heterogeneity increment. [ABSTRACT FROM AUTHOR]

Nanocomposites have gained fame due to their characteristics and are used in many industries such as automotive, aerospace, and biomedical. Also, curled structures (arches) are deeply applicable in fields of engineering. So, in this paper, the influence of nanoparticles' aggregation on the behavior of the dispersed elastic waves in the hybrid nanocomposite arches is evaluated for the first time. The arches are supposed to be made of hybrid multi-scale nanocomposite reinforced with single-walled carbon nanotubes and carbon fibers. The physical properties of arches are calculated in the framework of the rule of the mixture and the Eshelby–Mori–Tanaka homogenization model. The theoretical formulation of kinetic relations of the arches is presented based on the Euler–Bernoulli curved beam theory. Moreover, Hamilton's principle is applied to obtain the partial differential governing equations of arches. In the next step, an analytical solution method is implemented to solve the derived partial differential equations, and then, the frequency and velocity of the dispersed waves will be calculated. Next, the impacts of different effective parameters on the change of wave dispersion of hybrid nanocomposite arches are comprehensively studied. Finally, the obtained outcomes are reported in detail namely the correlations between phase velocity, wave frequency, weight fraction, etc. [ABSTRACT FROM AUTHOR]