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Highlights A strategy based on metal-organic decomposition is proposed to enhance the tube-tube interactions of carbon nanotubes (CNTs). The robust tube-tube interactions of CNTs enhance both EMI shielding performance and mechanical properties of CNT film. This innovative approach provides an effective way to obtain high-performance CNT film.

The organic passivated carbon nanotube (CNT)/silicon (Si) solar cell is a new type of low‐cost, high‐efficiency solar cell, with challenges concerning the stability of the organic layer used for passivation. In this work, the stability of the organic layer is studied with respect to the internal and external (humidity) water content and additionally long‐term stability for low moisture environments. It is found that the organic passivated CNT/Si complex interface is not stable, despite both the organic passivation layer and CNTs being stable on their own and is due to the CNTs providing an additional path for water molecules to the interface. With the use of a simple encapsulation, a record power conversion efficiency of 22% is achieved and a stable photovoltaic performance is demonstrated. This work provides a new direction for the development of high‐performance/low‐cost photovoltaics in the future and will stimulate the use of nanotubes materials for solar cells applications. [ABSTRACT FROM AUTHOR]

Lattice defects significantly affect the mechanical performance of metallic materials. In this study, lattice defects of a carbon nanotube reinforced 2024 aluminum alloy (CNT/2024Al) composite were systematically investigated and the contribution of carbon nanotubes was illustrated. The results showed that dislocations and grain boundaries were closely related to the deformation behavior and lead to discontinuous yielding phenomena. Moreover, the carbon nanotubes reduced the stacking fault energy, which was conducive to forming stacking faults and a small number of twins in the composite. The stacking faults, twin boundaries, and intragranular Al 4 C 3 phases hindered dislocation motion, thus enhancing the mechanical properties of the composite. In addition, the novel formation mechanism of the 9R structure was revealed: the Σ 3 (1 1 ‾ 1) / (151) incoherent twin boundary may dissociate into two tilt walls bounding a 9R structure (zone axis: [ 1 ‾ 01 ]), which enriches understanding of the relationship between Σ 3 twin boundaries and the 9R structure. [Display omitted] • The discontinuous yielding phenomenon of a CNT/2024Al composite is clarified. • Stacking faults, twins and 9R structure are observed in CNT/2024Al composite. • Deformation twins can be induced by MAP and SAP twinning. • The Σ 3 (1 1 ‾ 1) / (151) incoherent twin boundary dissociates into two tilt walls, with the intermediate 9R structure. [ABSTRACT FROM AUTHOR]

Abstract Co-continuous morphology in polymer blends has been well demonstrated to reduce percolation threshold and enhance electrical conductivity by selective dispersion of carbon nanotubes in one phase or at interfaces. In this work, a flexible, co-continuous, and conductive poly(ethylene-co-1-octene)/thermoplastic polyurethane/multi-walled carbon nanotube (POE/TPU/MWCNT) composite has been fabricated by controlling the dispersion of MWCNTs in the TPU phase. The interfacial interaction between the two polymers in the composites has been enhanced by using a gentle crosslinking reaction. The percolation threshold of the composites decreased from 0.43 to 0.29 vol% and electrical conductivity rose more than one order of magnitude after gentle crosslinking because of the very continuous TPU/MWCNT phase, the MWCNT fillers selective distribution, and the strong interfacial interaction between the two polymers. Furthermore, the complex viscosity, storage modulus, tensile strength, and elongation at break of the composites were improved by the gentle crosslinking reaction. For example, the composites with 0.58 vol% MWCNT fillers achieved 1.4- and 2.4-fold improvement in tensile strength and elongation at break after gentle crosslinking, respectively. In addition, the flexibility of the composites was well maintained by the gentle crosslinking reaction, resulting in excellent piezoresistive behavior of the composites. The stability and reliability of the piezoresistive response of the composites were enhanced by the gentle crosslinking reaction, owing to the stability of the MWCNT conductive network and the strong interfacial interaction. We propose that a gentle chemical crosslinking reaction between the two polymers is an alternative method for improving electrical conductivity and stabilizing the conductive network for co-continuous conductive polymer composites. Highlights • The interfacial interaction between TPU and POE was enhanced by a gentle crosslinking reaction. • The very continuous TPU/MWCNT phase was found in the crosslinking POE/TPU/MWCNT composites. • The crosslinking composites exhibited high electrical conductivity and low percolation threshold. • The stability and reliability of piezoresistive response were enhanced by the gentle crosslinking reaction. • The gentle crosslinking reaction also enhanced the mechanical properties of the composites. [ABSTRACT FROM AUTHOR]

In this work, simultaneously enhanced thermal conductivity, heat dissipation and dielectric constant of poly(vinylidene fluoride) (PVDF) were prepared by adding ionic liquid (IL)-coated carbon nanotubes (IL@CNTs). IL@CNTs and common CNTs were melt-compounded with PVDF to prepare the composites, respectively. The results clearly demonstrated that IL@CNTs exhibited better dispersion and higher ability to form the percolated network structure. Studying on crystallization behaviors showed that IL@CNTs not only exhibited better nucleation effect on PVDF crystallization but also induced a large number of the polar β/γ-form crystallites formation in the composites. Thermal properties measurements showed that IL@CNTs exhibited more apparent role in enhancing the thermal conductivity of the composites. Specifically, IL@CNT endowed the composite sample with higher heat dissipation ability compared with the common CNTs during the cooling process. In addition, the largely enhanced dielectric constant was also achieved for the PVDF/IL@CNT composites. The mechanisms were analyzed and suggested to be mainly related to the improved dispersion and denser percolated network structure of IL@CNTs in the composites, the improved interfacial interaction between fillers and matrix, and the varied crystalline structure of the PVDF matrix. The prepared composites have great potential application as the heat management material of the flexible electronic devices. [ABSTRACT FROM AUTHOR]

• A comparative analysis about dispersion ability of six representative surfactants on CNTs was conducted. • The MD simulations and experimental investigations were combined to facilitate the comparison. • The inherent structures of surfactants and CNTs-surfactant ratios directly affected their adsorption behaviours on CNTs surface. • Triton X-100 and SDBS showed the strongest dispersion ability. Poor dispersion is a major obstacle limiting the practical application of carbon nanotubes (CNTs) in composites. A comparative analysis of the dispersion ability of six representative surfactants for CNTs was conducted using both molecular dynamics (MD) simulations and experimental investigations. The dispersion stability of the surfactant-assisted CNTs was characterised via ultraviolet–visible spectroscopy, surface potential analysis, and transmission electron microscope. The chemical structures of the surfactants and CNTs-surfactant ratios directly affected the adsorption behaviours of surfactants on CNTs surface, thus exerting significant impacts on the final dispersion effect. The interaction energy analysis showed that Triton X-100 and sodium dodecyl benzenesulfonate (SDBS) exhibited the strongest interaction with CNTs with respect to other surfactants, whereas sodium dodecyl sulfate (SDS) displayed the weakest interaction. The van der Waals forces were the main driving forces of this adsorption process. Several structural factors, such as the presence of benzene rings and long alkyl chains, were important and favourable in enhancing the adsorption efficiency of surfactants on CNTs surface. The MD simulation results also revealed that different concentrations of surfactants in the system led to different adsorption behaviours, as low amounts of surfactants tended to exhibit random adsorption without a particular orientation on CNTs surface. Based on the experimental results, Triton X-100 and SDBS showed the strongest dispersion ability, which was consistent with the MD calculation results. Notably, excess amounts of surfactants above the optimum amount caused the entanglement and agglomeration of CNTs owing to the interaction between unfavourable micelles. This study provides an effective guidance for the selection of optimal surfactants for CNTs dispersion. [ABSTRACT FROM AUTHOR]

A facile and one-step method is demonstrated to prepare carbon nanofibers (CNFs)-bridged porous carbon nanosheets (PCNs) through carbonization of the mixture of bacterial cellulose and potassium citrate. The CNFs bridge PCNs to form integrated porous carbon architecture with high specific surface area of 1037 m 2 g −1 , much higher than those of pure PCNs (381 m 2 g −1 ) and CNFs (510 m 2 g −1 ). As a consequence, the PCN/CNF composite displays high specific capacitance of 261 F g −1 , excellent rate capability and outstanding cycling stability (97.6% of capacitance retention after 10000 cycles). Moreover, the assembled symmetric supercapacitor with PCN/CNF electrodes delivers an ultrahigh energy density of 20.4 Wh kg −1 and outstanding cycling life (94.8% capacitance retention after 10000 cycles) in an aqueous electrolyte. [ABSTRACT FROM AUTHOR]

Objective To study single wall carbon nanotubes (SWCNT) and its role in inducing inflammatory cytokines in the cruor-fibrinolysis system of rat. Methods Twenty one Wistar rats were divided into four groups: 1) control; 2) low-dose SWCNT (0.15 mg/kg BW); 3) medium-dose SWCNT (0.75 mg/kg BW); 4) high-dose SWCNT (1.5 mg/kg BW): Intratracheal instillation of SWCNT suspensions was administered to rats once per day for 21 days. In order to assess the exposure effect of SWCNT to the rats, activity of Inflammatory cytokine was measured and markers of cruor-fibrinolysis system were studied via ELSIA. Also, change in clotting time was recorded and histopathology was studied. Results IL-6 and IL-8 concentrations of rats exposed to SWCNT were significantly higher than those in controls (P<0.05). The activity of inflammatory cytokines and histopathological change indicated that oxidative damage occurred. Change in clotting time in rats exposed to SWCNT decreased compared with controls. Meanwhile, t-PA (tissue-tupe plassminogen activator) and AT-111 (antithrombin-lll) levels in rats exposed to particulates increased or decreased significantly compared with controls (P<0.05). A similar trend was observed for D-dimer (D2D) levels, indicating that SWCNT can impact the cruor-fibrinolysis system of rat. Conclusion The results from our study suggest that an increased procoagulant activity and reduced fibrinolytic activity in rats exposed to SWCNT can cause pulmonary oxidative stress and inflammation, due to the release of pro-thrombotic and inflammatory cytokines into the blood circulation of rat. [ABSTRACT FROM AUTHOR]

Abstract: Graphene nanosheet/carbon nanotube/polyaniline (GNS/CNT/PANI) composite is synthesized via in situ polymerization. GNS/CNT/PANI composite exhibits the specific capacitance of 1035Fg−1 (1mVs−1) in 6M of KOH, which is a little lower than GNS/PANI composite (1046Fg−1), but much higher than pure PANI (115Fg−1) and CNT/PANI composite (780Fg−1). Though a small amount of CNTs (1wt.%) is added into GNS, the cycle stability of GNS/CNT/PANI composite is greatly improved due to the maintenance of highly conductive path as well as mechanical strength of the electrode during doping/dedoping processes. After 1000 cycles, the capacitance decreases only 6% of initial capacitance compared to 52% and 67% for GNS/PANI and CNT/PANI composites. [Copyright &y& Elsevier]

Abstract: Carbon nanotube (CNT)/MnO2 composites are synthesized by reduction of potassium permanganate under microwave irradiation. The morphology and microstructure of samples are examined by scanning electron microscopy (SEM), transition electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Electrochemical properties are characterized by cyclic voltammetry (CV), galvanostatic charge/discharge and electrochemical impedance spectroscopy (EIS). Birnessite-type MnO2 homogeneously coats on the surfaces of CNTs. For CNT–15%MnO2 composite, the specific capacitance based on MnO2 is 944 (85% of the theoretical capacitance) and 522Fg−1 at 1 and 500mVs−1, respectively. When the content of MnO2 reaches 57wt%, the composites have the maximum power density (45.4kWkg−1, the energy density is 25.2Whkg−1). Therefore, CNT/MnO2 composites prepared by microwave irradiation are promising electrode materials in hybrid vehicle systems. [Copyright &y& Elsevier]

Synchronous enhancement of strength and ductility is a persistent challenge in the development and application of carbon nanotube (CNT)-reinforced aluminum matrix composites. This study proposed a low-temperature aging strategy to induce the nanoscale precipitates and evade the strength and ductility trade-off dilemma. The composites under various aging conditions were characterized in detail at the macro, micro, and nano scales. The precipitation behavior and strengthening mechanism were investigated systematically. Results indicated that the composite exhibited a better mechanical performance when aged at 100 °C. Compared to as-extruded composites, the yield and ultimate tensile strength of CNT/2024Al composites increased by 82.7 % and 64.8 %, respectively, whereas the elongation decreased by only 1.1 %. The results of microstructure and theoretical estimation suggested the dense nanoscale GP zones were primarily responsible for achieving the strength-ductility synergy. This present study on tailoring precipitate evolution could provide fundamental insights and references to enhance the mechanical properties of aluminum matrix composites. [Display omitted] • Strength-ductility synergy is achieved by a low-temperature aging strategy. • The enhancement in strength is primarily attributed to dense nano-scale GP zones. • A high volume of grain boundaries exacerbates the formation of GBPs and PFZ. • Neither CNT nor Al 4 C 3 can serve as the substrate for heterogeneous nucleation. [ABSTRACT FROM AUTHOR]

[Display omitted] • A nanofibrous composite membrane with photothermally induced reversible wettability is prepared. • PNIPAM improves the interfacial interaction and hence the durability of the nanofiber composite. • The composite membrane can separate different oil/water mixtures and emulsions with excellent recyclability. How to quickly, conveniently and efficiently separate different kinds of oil–water mixtures and emulsions remains a great challenge. Herein, we fabricate a photo-thermally responsive nanofiber composite membrane with switchable superwettability by carbon nanotubes (CNTs) adsorption onto electrospun polyurethane (PU) nanofibers and then poly (N-isopropyl acrylamide) (PNIPAM) modification. The PNIPAM enhances the interfacial interaction between CNTs and PU nanofibers without sacrificing the flexibility of the membrane. The outstanding photothermal conversion behavior endows the nanofiber composite with quick reversible conversion of superhydrophilicity and good hydrophobicity. The nanofiber composite membrane can successfully separate the oil/water mixture with different oil densities, oil-in-water emulsions at room temperature and water-in-oil emulsions under the assistance of the infrared light, with both high liquid permeation flux and separation efficiency. In addition, the PNIPAM/CNTs@PU shows superior cyclic separation performance. This multi-functional composite membrane exhibits promising applications in intelligent, smart and controllable separation of oil contaminated wastewater. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotubes (SWCNTs) based nanocomposites demonstrate remarkable electromagnetic interference (EMI) shielding potential. However, the efficient and rapid fabrication of SWCNT-based nanocomposite remains a technical challenge. This study successfully one-step synthesizes iron (Fe) nanoparticle-enriched SWCNTs (Fe@SWCNT) using the floating catalyst chemical vapor deposition (FCCVD) method in the aerosol phase. The aerosol-synthesized Fe@SWCNTs were directly integrated with carbon cloth (CC) and polydimethylsiloxane (PDMS) to develop a compelling nanocomposite film for multifunctional EMI shielding. The composite film exhibits exceptional shielding effectiveness of 50.2 dB in the X-band (8.2–12.4 GHz) with absolute shielding effectiveness (SSE t) of 3279.3 dB cm²/g. Notably, the film also displays rapid and uniform electrical heating at low voltages, reaching a temperature of 110.4 °C under a 1.0 V. Overall, this study reveals the potential applications of multifunctional textiles in fields such as EMI shielding, hydrophobicity, and thermal management. [Display omitted] • One-step synthesis of Fe@SWCNT in aerosol phase has been achieved. • The number of Fe nanoparticles can be well regulated by controlling the feeding rate. • The Fe@SWCNT film demonstrated EMI shielding of 50.2 dB at the X-band. • The composite film displays good hydrophobicity and electrical heating performance. [ABSTRACT FROM AUTHOR]

• Cable-like PI@CNTs is designed and prepared via an in-situ polymerization approach. • The PI@CNTs anode exhibits far better long-term cycling performance than pure PI. • The structure of PI@CNTs facilitates Li ion diffusion and electron transportation. Polyimide (PI) with C = O groups and C 6 rings is considered as a promising anode material for lithium ion batteries. However, the potential application of PI is extremely hindered by its inherent properties with unsatisfied lithium ions diffusion and electron conductivity. Herein, the PI nanoflakes are grown on the carbon nanotubes (CNTs) to construct a cable-like structure (PI@CNTs) via an in-situ polymerization approach. The dispersed PI nanoflakes provide shorter lithium ion transmission distance and the CNTs substrate promotes electron transportation, leading to enhanced electrochemical performance. When served as anode material, PI@CNTs exhibits a specific capacity of 493 mAh g−1 at 1 A g−1 after 2000 cycles, demonstrating remarkable long-term cycling properties. Moreover, the kinetic analysis reveals that the increased capacity can be ascribed to an enlarged diffusion-controlled process. In addition, the COMSOL simulation displays the high concentration of Li ions flux on the PI@CNTs surface. This work suggests a facile strategy to fabricate capable hierarchical polymer electrode materials for lithium ion batteries. [ABSTRACT FROM AUTHOR]

Single-walled carbon nanotubes (SWCNTs) are ideal candidates for transparent conductive films (TCFs) due to their excellent optical transparency and electrical conductivity. The geometry of SWCNTs, including the tube diameter, bundle length and bundle diameter, is vital to high-performance TCFs. Herein, we synthesized SWCNTs by floating catalyst chemical vapor deposition (FCCVD). The SWCNT geometries were tuned by hydrogen (H 2), and we found that the tube diameter, bundle length and bundle diameter increase with the H 2 concentration. Besides, we observed the formation of SWCNT loop at the tube ends. Both the number and circumference of loops increased with the increment of bundle length. Further, the loops were also found to affect the conductivity of SWCNT thin film. Excessive number of loops with large size could reduce the conductivity of SWCNT thin film. At the optimized H 2 concentration, we obtained the SWCNT TCF with sheet resistances of 290 and 95 Ω/sq. for the pristine and AuCl 3 doped SWCNT films, respectively, at 90% transmittance. Our work demonstrates the importance of H 2 for SWCNT synthesis and the critical role of loops on film conductivity, blazing new ideas for future research to obtain SWCNT TCFs with improved performance. [Display omitted] • The geometry of SWCNT (i.e. tube diameter and length) is controlled by H 2. • As the length of SWCNT increases, the number and size of SWCNT loops increase. • The large proportion of the loops in SWCNT reduces the conductivity of TCFs. [ABSTRACT FROM AUTHOR]

[Display omitted] • High spin polarized ultrafine Rh nanoparticles/CNT is designed and synthesized. • Rh/CNT is efficient and stable nitrogen reduction reaction catalyst. • Electrolyte adjustment is used to optimize catalytic performances. • High spin electron state of Rh/CNT improves the activity for nitrogen reduction. The electroreduction of nitrogen (N 2) to ammonia (NH 3) is gravely restricted by its inherent kinetic complexity and energy-intensive multi-electron steps. Most literature has reported that the first step of N 2 adsorption and activation is the bottleneck of electrochemistry N 2 reduction reaction (NRR). However, it is a considerable challenge to understand the design rule of catalysts with perfect performances for NRR. Here, as a proof-of-concept experiment, we apply the theoretical calculations with the experimental studies to reveal the influence of the high spin related to the size effect and the charge density related to the substrate effect on the catalytic activity of NRR catalysts. The desired ultrafine Rh nanoparticles anchored on CNT exhibit excellent NRR performances, especially high NH 3 yield (26.91 μg h−1 mg cat. −1), Faradaic efficiency (23.48 %) and energy efficiency (20.50 %), outperforming most reported NRR electrocatalysts under ambient conditions, which can be attributed to excellent synergism of the high-spin polarization of Rh NPs and the charge exchange between Rh NPs and the substrate that can promote N 2 adsorption and activate its intrinsic N N triple bond. [ABSTRACT FROM AUTHOR]