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• GNP and MWCNT collectively affect mechanical stability and electrical property of the PFHD. • Optimized PFHD contains 67 wt% MWCNT and 33 wt% GNT. • Paper-based low cost and rapid heating device shows a T max of 116.3 ℃ at 2.5 V. • Flexible and lightweight heating device ideal for PEMFC driven aerial vehicle can serve as a disposable container for hydrogen fuel. A paper-based flexible heating device (PFHD - paper-based flexible heating device) composed of a cellulose paper substrate and a carbonaceous functional electrode is reported. The functional composite electrodes containing graphene nanoplatelets (GNP - graphene nanoplatelets) and multi-walled carbon nanotubes (MWCNT) in various compositional ratios were prepared by dip-coating the oxygen plasma-treated paper substrate into the composite ink, and subsequently dried at 110 ℃ for 30 min to prepare PFHDs. The electrochemical characteristics and heat generation properties of PFHDs indicated that the GNP component in the functional electrode enhanced the electrical conductivity of the electrode, and the physical stability was enhanced mainly by the MWCNT component. Accordingly, PFHD 0.33 which contains 33 % GNP and 67 % MWCNT in the functional electrode shows excellent heating performance with high stability and areal rated power of 0.68 W cm−2 (specific rated power = 45 W g−1). The measured sensitivity of PFHD 0.33 is 31.50 ℃ V−1 at the applied DC voltage of 0.1–2.0 V. [Display omitted] [ABSTRACT FROM AUTHOR]

A facile strategy is designed for the fabrication of flexible and free-standing ternary CoSnO 3 /graphene/carbon nanotubes (CoSnO 3 /GN/CNTs) composite papers through a simple filtration, followed by annealing process. The CoSnO 3 /GN/CNTs composite papers with high flexibility and tailorability can be easily fabricated. The CoSn(OH) 6 nanoparticles/graphene oxide/carbon nanotubes (CoSn(OH) 6 /GO/CNTs) composite papers obtained by a simple filtration method are transformed into CoSnO 3 /GN/CNTs composite papers after a thermal treatment process. In this unique composite structure, CoSnO 3 nanoparticles (nanocubes and nanoboxes) are embedded homogenously into the 3D framework of graphene and carbon nanotubes, respectively, in which offers not only a 3D conductive network and a dual restriction on the aggregation of CoSnO 3 nanoparticles, but also accommodates the large volume expansion of CoSnO 3 nanoparticles. When used directly as binder- and conductive agent-free anodes for lithium-ion batteries, the CoSnO 3 /GN/CNTs composite papers exhibit superb electrochemical properties including extraordinary reversible capacities, superior rate capabilities and stable cycle performances compared to CoSnO 3 nanoparticles and GN/CNTs paper, suggesting a new pathway for the rational engineering of anode materials. [ABSTRACT FROM AUTHOR]

The increasing demands for portable, wearable, and implantable sensing devices have stimulated growing interest in innovative electrode materials. In this work, we have demonstrated that printing a conductive ink formulated by blending three-dimensional (3D) porous graphene–carbon nanotube (CNT) assembly with ionic liquid (IL) on two-dimensional (2D) graphene paper (GP), leads to a freestanding GP supported graphene–CNT–IL nanocomposite (graphene–CNT–IL/GP). The incorporation of highly conductive CNTs into graphene assembly effectively increases its surface area and improves its electrical and mechanical properties. The graphene–CNT–IL/GP, as freestanding and flexible substrates, allows for efficient loading of PtAu alloy nanoparticles by means of ultrasonic-electrochemical deposition. Owing to the synergistic effect of PtAu alloy nanoparticles, 3D porous graphene–CNT scaffold, IL binder and 2D flexible GP substrate, the resultant lightweight nanohybrid paper electrode exhibits excellent sensing performances in nonenzymatic electrochemical detection of glucose in terms of sensitivity, selectivity, reproducibility and mechanical properties. [ABSTRACT FROM AUTHOR]

Adding or mixing CNTs to different matrix materials may change and enhance the functionality in particular, the electrical properties of the formed CNTs nanocomposite. Keywords: nanoparticles; multiwalled carbon nanotubes; graphene; 2D layered materials; perovskites; surface plasmon resonance; 2D photonic crystals; sensors EN nanoparticles multiwalled carbon nanotubes graphene 2D layered materials perovskites surface plasmon resonance 2D photonic crystals sensors 1 4 4 12/23/22 20220611 NES 220611 This Special Collection on I Nanomaterials and Nanotechnology i is devoted to the collection of articles from several different research fields and applications of nanotechnology which have been presented at the NanoMITe Annual Symposium and Nanotechnology Malaysia Annual Symposium (NanoSym2019) in Putrajaya during 21 SP st sp -22 SP nd sp August 2019. Another interesting topic, the multiwalled carbon nanotubes (CNTs), unique one-dimensional carbon structures, is the object of the third selected paper in this field by P.Y. Foong. In this paper, multiwalled carbon nanotubes were proposed as the susceptor for the microwave welding of high-density polyethylene, considering multiwalled carbon nanotube is a good microwave absorber. [Extracted from the article]

An analytical model of the interaction between Al and C atoms at the interfaces formed by carbon nanoparticles and aluminum is proposed. The model is convenient for practical use in calculating the free energy of the interface, which is essential for nanocomposites and determines their mechanical, thermophysical, and other properties. The paper considers nanoparticles of various structures that are used in the development of aluminum matrix composites: fullerenes of various diameters, single-layer carbon nanotubes of metal and semiconductor types of various radii and chirality, graphene, and graphite. The proposed model employs the Lennard–Jones potential and approximately takes into account the effect of the local structure of the nanoparticle on the interaction of pairs of aluminum and carbon atoms using additional parameters. In this paper, we assume that the average local curvature of the nanoparticle surface determines the depth and location of the potential well. The work is supplemented with the study of interphase interaction in the framework of the density functional theory. The comparison of the results of calculations performed using approximations of various levels of accuracy is used to establish the limits of applicability of the proposed potential, and the possibility of its application in the study of interfacial interaction in nanocomposites based on aluminum and nanocarbon is shown. [ABSTRACT FROM AUTHOR]

In this study, the graphene supercapacitor based on the paper substrate, polyvinyl alcohol electrolyte and BaTiO3/poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) composite separator has been fabricated. The morphology of the separator, electrolyte and electrode surfaces and graphene two-dimensional sheets have been characterized using scanning electron microscopy and transmission electron microscopy. The specific capacitances of the graphene supercapacitor were measured using C-V curves and charge/discharge curves. The specific capacitances of the graphene supercapacitor using C-V curves and charge/discharge curves were 343 F g−1 and 195 F g−1 respectively. The Nyquist curve and Bode curve of the graphene supercapacitor have been measured using the electrochemical impedance spectroscopy analysis. From the Nyquist curve the internal resistance was 42 Ω. The supercapacitor based on the graphene two-dimensional sheets electrode and BaTiO3/PEDOT:PSS composite separator represents a progressive type of supercapacitors with excellent performance. [ABSTRACT FROM AUTHOR]

The review presents the results of modeling of the solvation of nanoparticles with deep eutectic solvents that act as stabilizers of metal nanoparticles, which provide a new platform for nanoparticle technology. It is calculated that there is a slower dynamics of solvent molecules, i.e., a slowing down of water near solutes. Such water has limited movement and cannot be organized into tetrahedral forms, in contrast to water in volume. Also, the paper describes systematic studies of the adsorption configuration, distribution density and adsorption energy of molecules H$_{2}$O, CO$_{2}$, CH$_{4}$, N$_{2}$, C$_{8}$H$_{18}$ and fluorocarbons C$_{3}$F$_{8}$ and C$_{5}$F$_{12}$ on the surface of kaolinite (0 0 1). Water adsorption is initiated and occurs due to the growth of clusters around surface groups, which is mainly regulated by the interactions of hydrogen bonds. Further, the paper investigates theoretically physical and mechanical properties of nanoscale systems, in particular, nanotips, amorphous carbon monolayer and nanoparticles. It is shown that the single-layer amorphous carbon is surprisingly stable and is deformed with a high ultimate strength without the propagation of cracks from the point of failure. The sliding on amorphous polyethylene and silicon studied using the method of molecular dynamics is described. The paper also discusses the dependencies of the friction force, acting on nanoparticles, on their velocity and sizes, in particular, the contact area, the structure and the type of the material, as well as on the direction of their shear and temperature. At an angle of rotation $ 45^\circ $, the silicon friction forces reach a minimum value, which can be termed superlubricity. The molecular dynamics modeling of the surface of carbon nanotubes, chitosan, polyvinyl acetate, titanium dioxide, $α$-quartz and zeolite is described to solve application problems ranging from reaction control to targeted delivery and creation of new drugs. The general principles have been identified that artificial water channels made of carbon nanotubes porins must satisfy, which can serve as a basis for further experiments. The organic modification mainly forms a modifier layer by crosslinking the hydrogen bond with the substrate, the flatness of the modified layer is strongly influenced by the type and concentration of the modifier. [ABSTRACT FROM AUTHOR]

This paper briefly introduced the classical fatigue fracture mechanism of rubber composites and reviewed the latest research process in the flurorubber composites with diatomite, nano zinc oxide, attapulgite, cerium dioxide, graphene, and carbon nanotubes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pulsed laser radiation forms a graphene/SWCNT hybrid film with a developed surface. • Functionalization of graphene/SWCNT film with BaO nanoparticles reduces the work function. • Emission current of carbon film increased by 42 times due to functionalization with BaO. • Hybrid carbon film with BaO nanoparticles can be used as efficient field cathode. This paper presents the manufacturing technology of hybrid nanostructures based on a buffer layer of reduced graphene oxide (rGO) flakes with vertical single-walled carbon nanotubes (SWCNTs) and their bundles functionalized with BaO nanoparticles. Using density functional theory (DFT) calculations, supercells of rGO/SWCNT/BaO films were constructed and the patterns of the electron work function were revealed. It has been demonstrated that the electron work function is influenced by both the mass fraction of BaO nanoparticles and the inter-tube distance. Branched carbon nanostructure was formed using a pulsed laser irradiation. Fragmentation of BaO nanoparticles on the carbon surface was achieved. It was shown that after laser treatment, Ba(NO 3) 2 particles up to 200 nm in size were fragmented into smaller BaO nanoparticles with sizes of a few nanometers, covering the nanotubes. The field emission current–voltage characteristics (CVCs) were measured and showed a 42-fold increase in emission current compared to the nanostructure without BaO functionalization and laser treatment. BaO-functionalized hybrid carbon nanostructures are predicted to be efficient field cathodes, with a current density of at least 2 A/cm2, for use in X-ray tubes, field emission displays, and vacuum microwave devices. [ABSTRACT FROM AUTHOR]

The aim of the paper is to investigate the effect of size of multiwalled carbon nanotubes (MWCNTs) as additives for dispersion in gear oil to improve the tribological properties. Since long pristine MWCNTs tend to form clusters compromising dispersion stability, they are mildly processed in a ball mill to shorten the length and stabilized with a surfactant before dispersing in lubricant. Investigations are made to assess the effect of ball milling on the size and structure of MWCNTs using electron microscopy and Raman spectroscopy. The long and shortened MWCNTs are dispersed in EP 140 gear oil in 0.5% weight. The stability of the dispersed multiwalled carbon nanotubes is evaluated using light scattering techniques. The antiwear, antifriction, and extreme pressure properties of test oils are evaluated on a four-ball wear tester. It is found that ball milling of MWCNTs has a strong effect on the stability and tribological properties of the lubricant. From Raman spectroscopy, it is found that ball milling time of up to 10 hours did not produce any defects on the surface of MWCNTs. The stability of the lubricant and the antiwear, antifriction, and extreme pressure properties have improved significantly with dispersion shortened MWCNTs. Ball milling for longer periods produces defects on the surface of MWCNTs reducing their advantage as oil additives. [ABSTRACT FROM AUTHOR]

The addition of SiC or TiC nanoparticles to polycrystalline alumina matrix has long been known as an efficient way of improving the mechanical properties of alumina-based ceramics, especially strength, creep, and wear resistance. Recently, new types of nano-additives, such as carbon nanotubes (CNT), carbon nanofibers (CNF), and graphene sheets have been studied in order not only to improve the mechanical properties, but also to prepare materials with added functionalities, such as thermal and electrical conductivity. This paper provides a concise review of several types of alumina-based nanocomposites, evaluating the efficiency of various preparation methods and additives in terms of their influence on the properties of composites. [ABSTRACT FROM AUTHOR]

Nanotechnology is a dynamically developing field of science, due to the unique physical, chemical and biological properties of nanomaterials. Innovative structures using nanotechnology have found application in diverse fields: in agricultural and food industries, where they improve the quality and safety of food; in medical and biological sciences; cosmetology; and many other areas of our lives. In this article, a particular attention is focused on carbon nanomaterials, especially graphene, as well as carbon nanotubes and carbon quantum dots that have been successfully used in biotechnology, biomedicine and broadly defined environmental applications. Some properties of carbon nanomaterials prevent their direct use. One example is the difficulty in synthesizing graphene-based materials resulting from the tendency of graphene to aggregate. This results in a limitation of their use in certain fields. Therefore, in order to achieve a wider use and better availability of nanoparticles, they are introduced into matrices, most often polysaccharides with a high hydrophilicity. Such composites can compete with synthetic polymers. For this purpose, the carbon-based nanoparticles in polysaccharides matrices were characterized. The paper presents the progress of ground-breaking research in the field of designing innovative carbon-based nanomaterials, and applications of nanotechnology in diverse fields that are currently being developed is of high interest and shows great innovative potential. [ABSTRACT FROM AUTHOR]

In this study, we aimed to provide the recommended occupational exposure limits (OELs) for multi-walled carbon nanotubes (MWCNTs) and graphene nanomaterials based on data from a subchronic inhalation toxicity study using a lung dosimetry model. We used a no observed adverse effect level (NOAEL) of 0.98 mg m−3 and 3.02 mg m−3 in rats for MWCNTs and graphene, respectively. The NOAELs were obtained from a 13-week inhalation study in rats. The deposition fractions of MWCNTs and graphene in the respiratory tract of rats and humans were calculated by using the multi-path particle dosimetry model (MPPD model, v3.04). The deposition fraction in the alveolar region was 0.0527 and 0.0984 for MWCNTs and 0.0569 and 0.1043 for graphene in rats and human lungs, respectively. Then, the human equivalent exposure concentrations (HECs) of MWCNTs and graphene were calculated according to the method by the National Institute for Occupational Safety and Health (NIOSH). The HEC was estimated to be 0.17 mg m−3 for MWCNTs and to be 0.54 mg m−3 for graphene, which was relevant to the rat NOAEL of 0.98 mg m−3 and 3.02 mg m−3 for MWCNTs and graphene, respectively. Finally, we estimated the recommended OELs by applying uncertainty factors (UFs) to the HEC as follows: an UF of 3 for species differences (rats to humans), 2 for an experimental duration (subchronic to chronic), and 5 for inter-individual variations among workers. Thus, the OEL was estimated to be 6 μg m−3 for MWCNTs and 18 μg m−3 for graphene. These values could be useful in preventing the adverse health effects of nanoparticles in workers. [ABSTRACT FROM AUTHOR]

Abstract: SnO2–graphene–carbon nanotube (SnO2–G–CNT) mixture is synthesized using graphene oxide as precursor for application as anode material in rechargeable Li ion batteries. It is shown that the SnO2 nanoparticles of 3–6nm in diameter are not only attached onto the surface of graphene sheets by anchoring with surface functional groups, but they also are encapsulated in pore channels formed by entangled graphene sheets. The incorporation of carbon nanotubes reduces the charge transfer resistance of the anode made from the mixture through the formation of 3D electronic conductive networks. The SnO2–G–CNT anodes deliver remarkable capacities of 345 and 635mAhg−1 at 1.5 and 0.25Ag−1, respectively. Flexible electrodes consisting of highly-aligned SnO2–G–CNT papers are also prepared using a simple vacuum filtration technique. They present a stable capacity of 387mAhg−1 at 0.1Ag−1 after 50 cycles through the synergy of the high specific capacity of SnO2 nanoparticles and the excellent cycleability of G–CNT paper. [Copyright &y& Elsevier]

Carbon reinforcements are used to improve the mechanical properties of cement, allowing the preparation of a strengthened and toughened composite. Functionalization through a reaction with acid is necessary to guarantee both a good dispersion in water and a strong interaction with cement. Different functionalized reinforcements improve the mechanical properties of the composites in comparison with pristine cement. The use of a combination of carbon fibers, carbon nanotubes, and graphene nanoplatelets were analyzed in order to verify their synergistic effect. The use of functionalized carbon nanotubes and carbon fibers demonstrates an improvement of 71% in flexural strength and 540% in fracture energy. [ABSTRACT FROM AUTHOR]

This study focuses on epoxy hybrid systems prepared by incorporating multi-wall carbon nanotubes (MWCNTs) and graphene nanosheets (GNs) at two fixed filler amounts: below (0.1 wt%) and above (0.5 wt%), with varying MWCNT:GN mix ratios. The hybrid epoxy systems exhibited remarkable electrical performance, attributed to the π–π bond interactions between the multi-wall carbon nanotubes and the graphene layers dispersed in the epoxy resin matrix. The material's properties were characterized through dynamic mechanical and thermal analyses over a wide range of temperatures. In addition to excellent electrical properties, the formulated hybrid systems demonstrated high mechanical performance and thermal stability. Notably, the glass transition temperature of the samples reached 255 °C, and high storage modulus values at elevated temperatures were observed. The hybrid systems also displayed thermal stability up to 360 °C in air. By comparing the mechanical and electrical performance, the formulation can be optimized in terms of the electrical percolation threshold (EPT), electrical conductivity, thermostability, and mechanical parameters. This research provides valuable insights for designing advanced epoxy-based materials with multifunctional properties. [ABSTRACT FROM AUTHOR]

• G-CNTs-FeCo grown by vertically electrochemical exfoliation and hydrothermal. • FeCo growing on graphene can enhance electrochemical performance. • FeCo acts as catalyst for growing CNTs on graphene. • Electrochemical performance of G-CNTs-FeCo is better than pure graphene. • CNTs and FeCo growing on the graphene enhance conductivity and capacity. In this work, we grow CNTs on electrochemical exfoliation graphene with few FeCo(G-CNTs-FeCo) by hydrothermal as a new supercapacitors electrode. It has excellent specific capacitance (560.26 F/g at 1 mV/s) and low charge transfer resistance (30.79 Ω). The supercapacitor electrode exhibits better electron conductivity and electrochemical performance than pure graphene which was found to combine the merit of graphene, CNTs and FeCo metals. This paper would help to provide a method to improve graphene SCs performance. [ABSTRACT FROM AUTHOR]

Carbon is one of the most abundant elements on Earth. In addition to the well-known crystallographic modifications such as graphite and diamond, other allotropic carbon modifications such as graphene-based nanomaterials and carbon nanotubes have recently come to the fore. These carbon nanomaterials can be designed to help deliver or target drugs more efficiently and to innovate therapeutic approaches, especially for cancer treatment, but also for the development of new diagnostic agents for malignancies and are expected to help combine molecular imaging for diagnosis with therapies. This paper summarizes the latest designed drug delivery nanosystems based on graphene, graphene quantum dots, graphene oxide, reduced graphene oxide and carbon nanotubes, mainly for anticancer therapy. [ABSTRACT FROM AUTHOR]

Nano-sized carbons, such as graphene nanoparticle (GNP) and multiwall carbon nanotube (MWCNT), have attracted a great deal of attention due to their extraordinary intrinsic properties. Extensive research has been done on each carbon material for epoxy nanocomposites but only a few have ventured into a comparison study. In this paper, the effect of GNP and MWCNT, at various filler loadings, on the mechanical, thermal and dielectric properties of epoxy nanocomposites have been investigated. The experimental results demonstrate that GNP filled epoxy nanocomposites showed higher thermal and dielectric properties, but slightly lower mechanical properties compared to the MWCNT filled epoxy nanocomposites. The tensile strength, flexural strength, thermal conductivity and dielectric constant of GNP filled epoxy nanocomposites improved up to 11%, 17%, 126%, and 171% respectively, and MWCNT filled epoxy nanocomposites improved up to 26%, 29%, 60%, and 73% respectively. [ABSTRACT FROM AUTHOR]

Nowadays, a strong demand exists for printable materials with multifunctionality and proper rheological properties to overcome the limitations to deposit layer-by-layer in additive extrusion. The present study discusses rheological properties related to the microstructure of hybrid poly (lactic) acid (PLA) nanocomposites filled with graphene nanoplatelets (GNP) and multiwall carbon nanotubes (MWCNT) to produce multifunctional filament for 3D printing. The alignment and slip effects of 2D-nanoplatelets in the shear-thinning flow are compared with the strong reinforcement effects of entangled 1D-nanotubes, which govern the printability of nanocomposites at high filler contents. The mechanism of reinforcement is related to the network connectivity of nanofillers and interfacial interactions. The measured shear stress by a plate–plate rheometer of PLA, 1.5% and 9% GNP/PLA and MWCNT/PLA shows an instability for high shear rates, which is expressed as shear banding. A rheological complex model consisting of the Herschel–Bulkley model and banding stress is proposed for all considered materials. On this basis, the flow in the nozzle tube of a 3D printer is studied by a simple analytical model. The flow region is separated into three different regions in the tube, which match their boundaries. The present model gives an insight into the flow structure and better explains the reasons for printing enhancement. Experimental and modeling parameters are explored in designing printable hybrid polymer nanocomposites with added functionality. [ABSTRACT FROM AUTHOR]

This review summarizes the current knowledge on current and future applications of carbon nanoparticles in medicine. The carbon nanoparticle family has a large number of representatives with unique physicochemical properties that make them good candidates for use in clinical medicine. The best-known (and most researched) carbon nanoparticles include graphene, graphene oxide, and carbon nanotubes. The main direction of use involves medical diagnostics, which includes bioimaging and the detection of chemicals or metabolites present in the body. Since the question of nanoparticle toxicity has not been fully answered, the use of nanoparticles in the fields of therapeutics (drug delivery), regenerative medicine (cell scaffolding, tissue engineering), and vaccine production is still under research and many in vivo studies are ongoing. These preclinical studies suggest that carbon nanoparticles have great potential for diagnosis and treatment; the results show that the nanoparticles used do not have significant toxic effects; however, great caution is needed before nanoparticles are introduced into routine clinical practice. [ABSTRACT FROM AUTHOR]

Although robust chemical vapor detection by chemielectric point sensors remains as a largely unmet challenge at present, the best performance to date and the most likely avenue for future progress is with sensor designs in which the transductive element is a disordered nanostructured material. We here review the evidence for this claim, with illustrations drawn from recent work on sensors made from gold nanoparticles, carbon nanotubes, and reduced graphene oxide nanoplatelets. These examples can be regarded as being prototypical of disordered nanostructured films formed of primitive objects that are nanoscopic in 3-D, 2-D, and 1-D, respectively. [ABSTRACT FROM PUBLISHER]

Graphene nanoplatelets (GNPs) and multiwall carbon nanotubes (CNTs)-polypropylene (PP) composite materials for electromagnetic interference (EMI) shielding applications were fabricated as 1 mm thick panels and their properties were studied. Structural and morphologic characterization indicated that the obtained composite materials are not simple physical mixtures of these components but new materials with particular properties, the filler concentration and nature affecting the nanomaterials' structure and their conductivity. In the case of GNPs, their characteristics have a dramatic effect of their functionality, since they can lead to composites with lower conductivity and less effective EMI shielding. Regarding CNTs-PP composite panels, these were found to exhibit excellent EMI attenuation of more than 40 dB, for 10% CNTs concentration. The development of PP-based composite materials with added value and particular functionality (i.e., electrical conductivity and EMI shielding) is highly significant since PP is one of the most used polymers, the best for injection molding, and virtually infinitely recyclable. [ABSTRACT FROM AUTHOR]

Lung cancer is one of the malignant tumors with the highest mortality rate, and the detection of its tumor marker carcinoma antigen 125 (CA125) is significant. Here, an electrochemical immunoassay for CA125 was described. Nitrogen-doped reduced graphene oxide (N-rGO), carboxylated multi-walled carbon nanotubes (CMWCNTs) and gold nanoparticles (AuNPs) were applied to co-modify glassy carbon electrode (GCE), after incubation with Anti-CA125, the modified electrode was employed for the specific detection of CA125. The N-rGO@CMWCNTs (Nitrogen-doped reduced graphene oxide@carboxylated multi-walled carbon nanotubes) were used as a matrix, while CS@AuNPs (Chitosan@gold nanoparticles) with high conductivity and biocompatibility was immobilized on it through the reaction between carboxyl groups from CMWCNTs and amino groups, hydroxyl groups from chitosan (CS), resulting in the effect of double signal amplification. The immunosensor demonstrated excellent electrochemical performance with a linear detection range of 0.1 pg mL−1–100 ng mL−1, and the detection limit was as low as 0.04 pg mL−1 (S/N = 3). It had been verified that this method had good precision and high accuracy, and the immunosensor could remain stable for 10 days. This research provided a new method for the detection of CA125 in serum. [ABSTRACT FROM AUTHOR]

Carbon-based nanoparticles create a huge group with substantial applications in the diagnosis and therapy of diseases. Herein, the mechanism of their outstanding properties was discussed to form a new insight for handling their issues and developing new applications in medical field. In addition, the strategies to remove the possible toxicity effects were gathered and a complete literature review about their production by economical methods was done. At the end of this article, the future applications of these nanoparticles and their new derivatives were noted. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we report the effect of Fe film thickness on the growth, structure and electron emission characteristics of carbon nanotubes (CNTs) and multilayer graphene deposited on Si substrate. It is observed that the number of graphitic shells in carbon nanostructures (CNs) varies with the thickness of the catalyst depending on the average size of nanoparticles. Further, the Fe nanoparticles do not catalyze beyond a particular size of nanoclusters leading to the formation of multilayer graphene structure, instead of carbon nanotubes (CNTs). It is observed that the crystallinity of CNs enhances upon increasing the catalyst thickness. Multilayer graphene structures show improved crystallinity in comparison to CNTs as graphitic to defect mode intensity ratio (I D /I G ) decreases from 1.2 to 0.8. However, I 2D /I G value for multilayer graphene is found to be 1.1 confirming the presence of at least 10 layers of graphene in these samples. CNTs with smaller diameter show better electron emission properties with enhancement factor (γC  = 2.8 × 103) in comparison to multilayer graphene structure (γC  = 1.5 × 103). The better emission characteristics in CNTs are explained due to combination of electrons from edges as well as centers in comparison to the multilayer graphene. [Copyright &y& Elsevier]

The formation of novel structures by the passage of an electric current through graphite is described. These structures apparently consist of hollow three-dimensional graphitic shells bounded by curved and faceted planes, typically made up of two graphene layers. The curved structures were frequently decorated with nano-scale carbon particles, or short nanotubes. In some cases, nanotubes were found to be seamlessly connected to the thin shells, indicating that the formation of the shells and the nanotubes is intimately connected. Small nanotubes or nanoparticles were also sometimes found encapsulated inside the hollow structures, while fullerene-like particles were often seen attached to the outside surfaces. With their high surface areas and structural perfection, the new carbon structures may have applications as anodes of lithium ion batteries or as components of composite materials. [ABSTRACT FROM AUTHOR]

Abstract: Carbon nanofibres (CNFs) obtained by plasma-enhanced chemical vapour deposition are made of cone-shaped graphene layers, the opening angle of which has a significant influence on their properties: the smaller the angle, the closer the properties to those of carbon nanotubes. That angle is determined by the shape of the metal nanoparticle used to catalyse the growth. We show in this paper that the shape of Ni nanoparticle catalysts, and in turn the CNF properties, can be tuned during plasma-enhanced chemical vapour deposition, by the choice of the etchant gas. We show in particular that a water-containing etchant (H2O or H2O+H2) increases the growth rate by an order of magnitude at 600°C compared to an ammonia-containing etchant (NH3 or NH3 +H2), and leaves more elongated Ni particles with a cone angle three times smaller. We conclude that the cone angle and the growth rate are directly related, and propose a mechanism to explain that large difference between the two etchants [ABSTRACT FROM AUTHOR]

Underwater sound absorption materials with broadband and resistance to high pressure are crucial for noise control in the ocean. Herein a new method is presented to synergistically improve material's resistance to high pressure with broadband by hybridizing carbon nanotubes (CNTs) with graphene nanoplatelets (GNPs) in polydimethylsiloxane (PDMS) matrix. The micro‐structure shows the geometrical synergy between the nanoplatelets (GNPs) and nanotubes (MWCNT‐COOH). Besides, GNPs also form junctions with air micro‐voids. The underwater acoustic tests reveal that, compared with equivalent nanocomposites containing only CNTs or GNPs, the hybridized materials show significantly better sound absorption performance with a high hydrostatic pressure increased from 0.4 MPa to 1.0 MPa at the frequency range of 1500 Hz to 7000 Hz. Therefore, the hybridization of one‐dimensional (1D) and two‐dimensional (2D) nano‐carbon materials provides a new route for increasing the underwater sound absorption performance at high hydrostatic pressure. [ABSTRACT FROM AUTHOR]

This articles reviews till-date available literature on metal matrix composites reinforced with graphene, CNT and other carbonaceous materials. The article has a special focus on the mechanical, tribological and challenges associated with the fabrication of nanocomposites. Simultaneously, it reviews the synthesis, strengthening mechanism and applications of graphene along with research gap associated with graphene metal matrix nanocomposites (GMMNC). Carbonaceous nanofillers, e.g. Graphene, are known to have extraordinary mechanical, thermal and electrical properties along with multifaceted characteristics. These materials have the potential to become an ideal material in numerous application which requires reinforcement. Graphene nanoplatelets (GNP) suffers various challenges starting from its synthesis to the uniform distribution within the matrix material. Our concern is to give details on the challenges associated with graphene and metal matrix composites along with the solution so that new research can be done at its ease. Section 1 of the article gives a detailed analysis of various carbonaceous reinforcement materials. Preparation, processing and dispersion technique for graphene and composite material is given in section 2. Section 3 of the article deals with different matrix material used in MMNC along with the properties and challenges associated with it in tabulated form. Strengthening mechanism used for the enhancement of mechanical properties of composites is described in section 4, whereas, Section 5 deals with the applications and Research gap. [ABSTRACT FROM AUTHOR]

Nanotechnology is a dynamically developing field of science, due to the unique physical, chemical and biological properties of nanomaterials. Innovative structures using nanotechnology have found application in diverse fields: in agricultural and food industries, where they improve the quality and safety of food; in medical and biological sciences; cosmetology; and many other areas of our lives. In this article, a particular attention is focused on carbon nanomaterials, especially graphene, as well as carbon nanotubes and carbon quantum dots that have been successfully used in biotechnology, biomedicine and broadly defined environmental applications. Some properties of carbon nanomaterials prevent their direct use. One example is the difficulty in synthesizing graphene-based materials resulting from the tendency of graphene to aggregate. This results in a limitation of their use in certain fields. Therefore, in order to achieve a wider use and better availability of nanoparticles, they are introduced into matrices, most often polysaccharides with a high hydrophilicity. Such composites can compete with synthetic polymers. For this purpose, the carbon-based nanoparticles in polysaccharides matrices were characterized. The paper presents the progress of ground-breaking research in the field of designing innovative carbon-based nanomaterials, and applications of nanotechnology in diverse fields that are currently being developed is of high interest and shows great innovative potential.

The bioactive sphingolipid ceramide has many important roles in cell signaling processes, particularly in signaling programmed cell death in cancer. However, ceramide levels are often impaired in multi‐drug resistant and radiation resistant cancers due to the dysregulation of ceramide metabolism. Restoration of ceramide levels through external delivery therefore represents a potential therapeutic target for the treatment of resistant cancers. However, as a lipid, ceramide is extremely hydrophobic and requires a delivery system to enter cells. Here we report the development of a method to load significant amounts of the long chain C16 and C24 ceramides onto oxidized graphene nanoribbons (O‐GNRs) derived from carbon nanotubes. Using O‐GNRs as a delivery system for these ceramides, we were able to induce significant biological effects in HeLa cells in conjunction with C6 ceramide and ultraviolet radiation treatment. However, we found that O‐GNRs themselves exert significant biological effects and can interfere with the actions of these ceramides and ultraviolet treatment. Loading of ceramides onto O‐GNRs did not have a significant effect on the entry of the nanoparticles into cells. Despite the need for further improvement, these data represent an important first step in the development of O‐GNRs as a delivery system for long chain ceramides. [ABSTRACT FROM AUTHOR]

The anisotropic diffusive behavior of nanoparticles with complex shapes attracts great interest due to its potential applications in many fields ranging from bionics to aeronautic industry. Although molecular dynamics (MD) simulations are used widely to investigate nanoparticle diffusion properties, universal methods to describe the diffusion process comprehensively are still lacking. Here, we address this problem by introducing diffusion tensor as it can describe translational and rotational diffusion in three dimensions both individually and their coupling. We take carbon triple sphere suspended in argon fluid as our model system. The consistency of our results and velocity autocorrelation function(VAF) method validates our simulations. The coupling between translational and rotational diffusion is observed directly from analyzing diffusion tensor, and quantified by coupling diffusion coefficient. Our simulation reveals non-trivial effect of some factors in diffusion at nanoscale, which was not considered in previous theories. In addition to introducing an effective method to calculate the diffusion tensor in MD simulations, our work also provides insights for understanding the diffusion process of arbitrary-shaped particles in nanoengineering. [ABSTRACT FROM AUTHOR]

In this perspective paper, we critically analyse the state-of-the-art of arc discharge technique of carbon nanoparticle synthesis. We discuss improving controllability of the arc discharge synthesis of carbon nanotubes, synthesis of graphene as well as general understanding of the synthesis process. Fundamental issues related to relationship between plasma parameters and carbon nanostructure characteristics are considered. Effects of electrical and magnetic fields applied during single-wall carbon nanotube synthesis in arc plasma are explored. Finally our personal opinion on what future trends will be in arc discharge synthesis is offered. [ABSTRACT FROM AUTHOR]

This review paper presents historical perspectives, recent advances and future directions in the multidisciplinary research field of plasma nanoscience. The current status and future challenges are presented using a three-dimensional framework. The first and the largest dimension covers the most important classes of nanoscale objects (nanostructures, nanofeatures and nanoassemblies/nanoarchitectures) and materials systems, namely carbon nanotubes, nanofibres, graphene, graphene nanoribbons, graphene nanoflakes, nanodiamond and related carbon-based nanostructures; metal, silicon and other inorganic nanoparticles and nanostructures; soft organic nanomaterials; nano-biomaterials; biological objects and nanoscale plasma etching. In the second dimension, we discuss the most common types of plasmas and plasma reactors used in nanoscale plasma synthesis and processing. These include low-temperature non-equilibrium plasmas at low and high pressures, thermal plasmas, high-pressure microplasmas, plasmas in liquids and plasma-liquid interactions, high-energy-density plasmas, and ionized physical vapour deposition as well as some other plasma-enhanced nanofabrication techniques. In the third dimension, we outline some of the 'Grand Science Challenges' and 'Grand Socio-economic Challenges' to which significant contributions from plasma nanoscience-related research can be expected in the near future. The urgent need for a stronger focus on practical, outcome-oriented research to tackle the grand challenges is emphasized and concisely formulated as from controlled complexity to practical simplicity in solving grand challenges. [ABSTRACT FROM AUTHOR]

This study presents multiwall and bamboo-like carbon nanotubes found in samples from the Allende carbonaceous chondrite using high-resolution transmission electron microscopy (HRTEM). A highly disordered lattice observed in this material suggests the presence of chiral domains in it. Our results also show amorphous and poorly-graphitized carbon, nanodiamonds, and onion-like fullerenes. The presence of multiwall and bamboo-like carbon nanotubes have important implications for hypotheses that explain how a probable source of asymmetry in carbonaceous chondrites might have contributed to the enantiomeric excess in soluble organics under extraterrestrial scenarios. This is the first study proving the existence of carbon nanotubes in carbonaceous chondrites. [ABSTRACT FROM AUTHOR]

Functional carbon-based nanomaterials have become important due to their unique combinations of chemical and physical properties, and also because of the increasing research efforts in various fields. A significant gap in nanotechnology is the disregarding of physicochemical transformation under real conditions for the examination and comparison on the effect of carbon based nanomaterials. In this study, the behavior of some carbon based nanomaterials (multi-walled carbon nanotubes and graphene nanoplatelets) in environmental media (sea water, soil, and airborne fine particulate) were evaluated by using the influence on nanomaterial physicochemical properties (size, zeta potential, surface chemistry, morphology and sedimentation) and on the toxicity of bacterium (gram positive and gram negative bacteria) to contribute to their environmental hazard and risk assessment on the environment. The bacteria were exposed to the carbon based nanomaterials, and cultivated on nutrient agar plates including each environmental media, and then counted for the colony forming units. The physicochemical properties of the carbon based nanomaterials dispersed in these environmental media were also investigated. Our results indicated that the toxicity depended on the type of environmental media and their concentration, and the physicochemical properties of the carbon based nanomaterials changed when compared to the results obtained in controlled conditions. [ABSTRACT FROM AUTHOR]

Abstract: Over the past decades, the development of high performance lightweight polymer nanocomposites and, in particular, of epoxy nanocomposites has become one the greatest challenges in material science. The ultimate goal of epoxy nanocomposites is to extrapolate the exceptional intrinsic properties of the nanoparticles to the bulk matrix. However, in spite of the efforts, this objective is still to be attained at commercially attractive scales. Key aspects to achieve this are ultimately the full understanding of network structure, the dispersion degree of the nanoparticles, the interfacial adhesion at the phase boundaries and the control of the localization and orientation of the nanoparticles in the epoxy system. In this Personal Account, we critically discuss the state of the art and evaluate the strategies to overcome these barriers. [ABSTRACT FROM AUTHOR]

Abstract: Visible‐light‐driven conversion of CO2 to CO and high‐value‐added carbon products is a promising strategy for mitigating CO2 emissions and reserving solar energy in chemical form. We report an efficient system for CO2 transformation to CO catalyzed by bare CoP, hybrid CoP/carbon nanotubes (CNTs), and CoP/reduced graphene oxide (rGO) in mixed aqueous solutions containing a Ru‐based photosensitizer, under visible‐light irradiation. The in situ prepared hybrid catalysts CoP/CNT and CoP/rGO show excellent catalytic activities in CO2 reduction to CO, with a catalytic rates of up to 39 510 and 47 330 μmol h−1 g−1 in the first 2 h of reaction, respectively; a high CO selectivity of 73.1 % for the former was achieved in parallel competing reactions in the photoreduction of CO2 and H2O. A combination of experimental and computational studies clearly shows that strong interactions between CoP and carbon‐supported materials and partially adsorbed H2O molecules on the catalyst surface significantly improve CO‐generating rates. [ABSTRACT FROM AUTHOR]

Immunosensors have experienced a very significant growth in recent years, driven by the need for fast, sensitive, portable and easy-to-use devices to detect biomarkers for clinical diagnosis or to monitor organic pollutants in natural or industrial environments. Advances in the field of signal amplification using enzymatic reactions, nanomaterials such as carbon nanotubes, graphene and graphene derivatives, metallic nanoparticles (gold, silver, various oxides or metal complexes), or magnetic beads show how it is possible to improve collection, binding or transduction performances and reach the requirements for realistic clinical diagnostic or environmental control. This review presents these most recent advances; it focuses first on classical electrode substrates, then moves to carbon-based nanostructured ones including carbon nanotubes, graphene and other carbon materials, metal or metal-oxide nanoparticles, magnetic nanoparticles, dendrimers and, to finish, explore the use of ionic liquids. Analytical performances are systematically covered and compared, depending on the detection principle, but also from a chronological perspective, from 2012 to 2016 and early 2017. [ABSTRACT FROM AUTHOR]

Nanocomposites based on PtPd nanoparticles with chemical ordering like disordered solid solution on surface of multilayer graphene have been prepared through thermal shock of mechanically obtained mixture of double complex salt [Pd(NH)][PtCl] and different carbon materials-exfoliated graphite, graphite oxide and graphite fluoride. An effect of original carbon precursors on formation of PtPd bimetallic nanoparticles was studied using X-ray absorption spectroscopy (XAFS), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). It was shown that the distribution of bimetallic nanoparticles over the multilayer graphene surface as well as the particles size distribution is controlled by the graphene precursors. For all nanocomposites, the surface of the nanoparticles was found to be Pd-enriched. In case when the thermal exfoliated graphite and graphite oxide were used as the graphene precursors a thin graphitized layer covered the nanoparticles surface. Such a graphitized layer was not observed in the nanocomposite, which used the fluorinated graphite as the precursor. [ABSTRACT FROM AUTHOR]

Herein, we examine the influence of adding functionalized graphene (FG), distinct expanded graphites and carbon nanofillers such as carbon black and multiwall carbon nanotubes on mechanical properties, morphology, pyrolysis, response to small flame and burning behavior of a V-2 classified flame-retarded polypropylene (PP). Among carbon fillers, FG and multilayer graphene (MLG) containing fewer than 10 layers are very effectively dispersed during twin-screw extrusion and account for enhanced matrix reinforcement. In contrast to the other fillers, no large agglomerates are detected for PP-FR/FG and PP-FR/MLG, as verified by electron microscopy. Adding FG to flame-retardant PP prevents dripping due to reduced flow at low shear rates and shifts the onset of thermal decomposition to temperatures 40°C higher. The increase in the onset temperature correlates with the increasing specific surface areas (BET) of the layered carbon fillers. The reduction of the peak heat release rate by 76% is attributed to the formation of effective protection layers during combustion. The addition of layered carbon nanoparticles lowers the time to ignition. The presence of carbon does not change the composition of the evolved pyrolysis gases, as determined by thermogravimetric analysis combined with online Fourier-transformed infrared measurements. FG and well-exfoliated MLG are superior additives with respect to spherical and tubular carbon nanomaterials. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Novel flower-like composite architecture was successfully synthesized by spray drying and post-calcinating method for the first time. Scanning electron microscopy and transmission electron microscopy observations confirmed that reduced graphene oxides/carbon nanotubes hybrid (rGO/CNTs) formed a flower-like micrometer structure and Cu2O, CuO (CuxO, x = 1 or 2) nanoparticles were decorated inside them. The photocatalytic properties were further investigated by evaluating the photodegradation of a pollutant methyl orange (MO). The experimental results indicated that this novel architecture enhanced photocatalytic performance with 96.2% decomposition of MO after 25 min in the presence of H2O2 under visible light irradiation, which was much higher than that of CuxO powders (33.2%). This could be attributed to the more efficient adsorption of MO molecules on flower-like rGO/CNTs and provide a high concentration of MO near to the CuxO nanoparticles, thus promoting the photocatalytic degradation process. [ABSTRACT FROM AUTHOR]