Search

Three different types of carbon screen-printed electrodes consisting of mesoporous carbon (MC), carbon nanofibers (CNF), and single-walled carbon nanotubes (SWCNT) were used as carbon supports for deposition of Ag, in the absence of reductant in the plating solution. The SPEs were characterized by Raman spectroscopy and show marked differences in their structure. To drive the metal deposition, the carbon supports were potentiostatically pre-treated in supporting electrolyte. The metal deposition occurred in AgNO3 solution and resulted in the formation of homogeneously distributed metal nanoparticles with type and amount depending on both the potential used in the pre-treatment step and the structure of the carbon electrodes. Larger metal amounts and higher particle densities (in the 109 cm−2 range) together with smaller particle mean sizes (in the 40- to 60-nm range) were obtained by using more negative potential for the pre-treatment. A further way to influence the characteristics of the metal deposit was based on double or triple consecutive pre-treatment/deposition cycles. The obtained results are discussed in view of the possible sources of electron supply, necessary for the formation of the metal particles on the carbon carrying substrates. [ABSTRACT FROM AUTHOR]

With the rapid development of science and technology, multifunctional wearable devices have become a major trend in medical field. There is an urgent need to fabricate multifunctional materials with thermal insulation, mechanical flexibility, piezoresistance, and adjustable heating behavior to cope with the thermal management and health monitoring of human body in the harsh environment. To address this issue, three-dimensional melamine-based carbon foams (CMF) have been developed, with sericin-functionalized carbon nanotubes (CNTs) and in situ-grown carbon nanofibers (CNFs) in the CMF skeleton. The strategy of hierarchical porous micro-nanostructure enhanced the synergistic effect between CNTs and CNFs, resulting in exceptional resilience at 0–80 % compressive strain and cyclic stability at 20 % strain. Such carbon foam composites demonstrated excellent piezoresistive sensing performance, wide pressure range (0–20 kPa), high sensitivity (S = 0.11 kPa−1), and quick response (response/recovery time of 150/120 ms). They also showed good thermal insulation and Joule heating properties, particularly in presenting strain-dependent Joule heating mode at low voltage. Such amazing characteristics provide inspiration for temperature regulation of flexible, energy-efficient heating devices, and make them promising for smart sportswear, human-machine interfaces, and wearable medical devices. [ABSTRACT FROM AUTHOR]

In the present work, the effects of carbon-based nanofillers (0.5 wt%), i.e., graphene nanoplatelets (GNPs), carbon nanofibers (CNFs), and carbon nanotubes (CNTs), on the cryogenic temperature (77 K) mechanical properties of carbon fiber reinforced polymers (CFRPs) were investigated. The study utilized an ex situ conditioning method for cryogenic tests. The nanofillers were mixed with the epoxy matrix by a solvent-free fluidized bed mixing technique (FBM), while unidirectional carbon fibers were impregnated with the resulting nanocomposites to manufacture CFRP samples. Optical microscopy was employed to analyze the dispersion of the carbon-based fillers within the matrix, revealing a homogeneous distribution in nanocomposites containing GNPs and CNFs. Fracture toughness tests confirmed the homogeneity of the GNP-loaded systems, showing an improvement in the stress intensity factor (KC) by 13.2% and 14.7% compared to the unmodified matrix at RT (25 °C) and 77 K, respectively; moreover, flexural tests demonstrated a general increase in flexural strength with the presence of carbon-based nanofillers at both temperature levels (RT and 77 K). Additionally, interlaminar shear strength (ILSS) tests were performed and analyzed using the same ex situ conditioning method. [ABSTRACT FROM AUTHOR]

This study presents the development of a facile and sensitive method of analysis for the determination of paracetamol. For this purpose, a boron doped diamond electrode (BDDE) was modified with a composite of carbon nanotubes (CNT), carbon nanofibers (CNF) and carbon black nanoballs (CNB). The voltammetric properties of paracetamol were studied, compared and discussed on unmodified BDDE, CNB/BDDE, CNF/BDDE, CNT/BDDE, CNB@CNF/BDDE, CNF@CNT/BDDE and CNF@CNB@CNT/BDDE. An increase in peak response (Ip) and a dramatic decrease in peak separation (ΔEp) were observed at electrodes in an order from bare BDDE to CNB/BDDE, CNF/BDDE, CNT/BDDE, CNB@CNF/BDDE, CNF@CNT/BDDE and CNF@CNB@CNT/BDDE. This clearly showed that the composite material of CNF@CNB@CNT provided an excellent surface on BDDE leading to a fast electrode reaction of paracetamol. Interestlingly, the amount composite layer on the voltammetry of paracetamol also caused a remarkable decrease in ΔEp and resulted in high electrocatalytic activity. The detection of paracetamol based on the BDDE modified with a composite of CNF@CNB@CNT exhibited stability, excellent selectivity and good sensitivity, with a low detection limit of 0.47±0.002 nM (based on 3sb/m) and wide linear range of 1.5 nM–200 nM. These results demonstrate that CNF@CNB@CNT/BDDE can serve as an ideal voltammetric platform for constructing a paracetamol sensor. The proposed electrochemical platform (CNF@CNB@CNT/BDDE) was also successfully applied for the determination of paracetamol in pharmaceuticals and body fluids. [ABSTRACT FROM AUTHOR]

Sub-fluorinated carbon nanofibers (F-CNFs) can be described as a non-fluorinated core surrounded by a fluorocarbon lattice. The core ensures the electron flux in the cathode during the electrochemical discharge in the primary lithium battery, which allows a high-power density to be reached. The ball-milling in an inert gas (Ar) of these F-CNFs adds a second level of conductive sp2 carbons, i.e., a dual sub-fluorination. The opening of the structure changes, from one initially similar multi-walled carbon nanotube to small lamellar nanoparticles after milling. The power densities are improved by the dual sub-fluorination, with values of 9693 W/kg (3192 W/kg for the starting material). Moreover, the over-potential of low depth of discharge, which is typical of covalent CFx, is suppressed thanks to the ball-milling. The energy density is still high during the ball-milling, i.e., 2011 and 2006 Wh/kg for raw and milled F-CNF, respectively. [ABSTRACT FROM AUTHOR]

The review systematizes data on the wide possibilities of practical application of carbon nanostructures. Much attention is paid to the use of carbon nanomaterials in medicine for the visualization of tumors during surgical interventions, in the creation of cosmetics, as well as in agriculture in the creation of fertilizers. Additionally, we demonstrate trends in research in the field of carbon nanomaterials with a view to elaborating targeted drug delivery systems. We also show the creation of nanosized medicinal substances and diagnostic systems, and the production of new biomaterials. A separate section is devoted to the difficulties in studying carbon nanomaterials. The review is intended for a wide range of readers, as well as for experts in the field of nanotechnology and nanomedicine. [ABSTRACT FROM AUTHOR]

Experimental studies were focused on decomposition of formic acid over carbon nanofibers (CNF) and carbon nanotubes (CNT) to produce pure hydrogen. These carbon materials were shown to provide decomposition of formic acid to form preferably hydrogen and carbon dioxide. It was established that structural features of carbon nanomaterials affect their activity in the decomposition of formic acid. The specific catalytic activity of CNF (ini) is at least twice as high as that of CNT (ini). The treatment of CNF (NaOH) with an alkali solution of NaOH is shown to improve noticeably both activity and selectivity of the catalytic decomposition of formic acid. The synthesized catalysts were characterized using X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM) and adsorption. It was shown by XPS that the alkali treatment of CNF results in the appearance of C–O–Na fragments on the carbon surface. • CNT and CNF with essentially different structures were synthesized. • The specific catalytic activity of CNF (ini) is at least twice as high as that of CNT (ini). • Alkali-treated CNF have significantly higher catalytic activity in the FA dehydrogenation. • Carbon nanofibers catalyzed FA decomposition to hydrogen and carbon dioxide. • The CNF (NaOH) catalyst is comparable in activity to the 0.2–0.4%Pt/N-graphene catalysts. [ABSTRACT FROM AUTHOR]

The addition of carbon nanotubes (CNTs) and graphene (G) to nitrogen-doped carbon nanofibers (N–C/CNFs) greatly improves their performance as sodium ion battery anodes. However, there is currently limited research on whether the introduction of nanocarbon materials will affect the surface functional groups, defects, and material structure. Herein, the classical G and CNT were introduced into the N–C/CNFs. And the addition of G promotes the transformation of nitrogen-containing functional groups (NFGs), resulting in a substantial pore structure and an enlarged interlayer distance, which enhances the macroscopic electrochemical performance significantly. The nitrogen-doped graphene/carbon composite nanofibers (N–G/CNFs) exhibit superior electrochemical performance compared to N–C/CNFs and nitrogen-doped carbon nanotube/carbon composite nanofibers (N–CNT/CNFs). After 200 cycles, the N–G/CNFs demonstrate a reversible capacity of 295 mA h g−1 at 0.05 A g−1, significantly higher than the capacities of N–C/CNFs (193 mA h g−1) and N–CNT/CNFs (237 mA h g−1). The Na3V2(PO4)3@C//N–G/CNFs exhibit promising energy and power densities. [ABSTRACT FROM AUTHOR]

In the present study, carbon nanofibers containing multi‐walled carbon nanotubes (MWCNTs) were fabricated and employed as electrodes for structural supercapacitors. Carbon nanofibers were utilized as the electrode material in structural supercapacitors to increase the specific surface area. Electrospun polyacrylonitrile (PAN) nanofibers underwent conversion to carbon nanofibers through stabilization and carbonization processes aided by thermal treatment. The specific surface area of the electrospun carbon nanofiber electrodes was further increased approximately 118 times (1946.9 m2/g) using an activation process in comparison with that of non‐activated carbon nanofibers (16.43 m2/g). Multifunctional supercapacitors were fabricated by employing electrospun carbon nanofibers and a vacuum resin infusion technique. The specific capacitance of activated carbon nanofibers (ACNF) and ACNF‐MWCNT exhibited significant improvement (14.87 and 48.25 mF/cm2, respectively) compared to non‐activated carbon nanofibers (CNF‐MWCNT: 1.71 mF/cm2). This improvement was attributed to the reduction in equivalent series resistance and the increase of the surface area of the nanofiber electrodes. Additionally, the carbon nanofiber electrodes contributed to an increased interlaminar fracture toughness of structural supercapacitors, acting akin to "Velcro" between fabric interfaces. This work serves as a "proof of concept" for a straightforward and efficient method to manufacture electrodes for structural supercapacitors based on the electrospinning technique. Highlights: Fabrication of carbon nanofibers containing MWCNTs using electrospinning.The carbon nanofiber as an electrode for structural supercapacitors.Simple and effective method.Dramatically improving specific capacitance of the supercapacitors. [ABSTRACT FROM AUTHOR]

Thermochemical conversion is a promising waste plastic recycling technology from both an economic and environmental point of view, as it can convert plastics into high-value chemicals. In this work, the co-production of hydrogen and carbon nanotubes (CNTs) by catalytic pyrolysis of polyethylene over Fe/ZSM-5 catalysts with different Fe loading (5, 10, 20 and 30 wt%) was investigated using a two-stage fixed bed reactor. The results show that the yield of CNTs and hydrogen increases first and then decreases with the increase of Fe loading. The 20Fe/ZSM-5 catalyst generated the highest CNTs yield of 262.24 mg/g PE and the maximum hydrogen production of 31.72 mmol/g PE. The fresh and spent catalysts were characterized by XRD, H2-TPR, SEM, TEM, etc., in order to explore the correlation between the catalytic activity and the Fe active metal load of the catalysts. The results showed that, within a certain range, the number of active sites increased with the increase of Fe loading, which promoted the conversion of hydrogen and CNTs. However, when the Fe loading reached 30%, the active particles agglomerated and inhibited the growth of CNTs. 30Fe/ZSM-5 catalyst produced many carbon nanoonions (CNOs) and carbon nanofibers (CNFs). Overall, in terms of the yield of the produced hydrogen and CNTs, the 20Fe/ZSM-5 catalyst shows the best catalytic performance. • A series of Fe-based catalyst was prepared for polyethylene pyrolysis. • Appropriate increase of Fe content can enhance CNTs and H 2 yield. • The highest CNTs yield of 262.24 mg/g PE was obtained from 20Fe/ZSM-5 catalyst. • The highest H 2 yield of 31.72 mmol/g PE was obtained from 20Fe/ZSM-5 catalyst. • More carbon nanofibers were obtained from 30Fe/ZSM-5 catalyst. [ABSTRACT FROM AUTHOR]

Hydrogen is a promising energy source for resolving the world's energy demands without releasing pollution, but storing hydrogen poses a significant challenge. Carbon materials such as activated carbon (AC), carbon nanotubes (CNT), carbon nanofibers (CNF), carbon nano-onions (CNOs) and graphene are potential substrate materials for hydrogen storage through physisorption/chemisorption due to their large surface areas and the ability to bind hydrogen. We investigate the hydrogen storage capacity of CNOs synthesized through thermal chemical vapour deposition using acetylene in this paper. SEM and XRD analysis revealed that the CNOs are spherical and comprised 18 shells at 850 °C and 7 shells at 1000 °C. However, the CNO interlayer thickness increased from 3.42 to 3.58 A0, which has a significant impact on the physisorption process. Functionalized CNOs were studied for their hydrogen storage capacities at 77 K and 1.5 atm, demonstrated a hydrogen storage capacity of 18.2%. The BET measurements revealed that the CNOs samples have a surface area of 642 m2/gm and FTIR showed a significant increase in –OH and –CH bond vibrations. Desorption studies of hydrogen reveal primarily two stages. The removal of hydrogen from CNO requires a first-stage activation energy of 6 kJ/mol and a second-stage activation energy of 127 kJ/mol, confirming the presence of both physiosorbed and chemisorbed hydrogen. This study found that hydrogen storage capacity of CNOs is extremely promising, and has a potential for mobile applications. • The hydrogen storage capacity of synthesized CNOs was determined. • The functional groups are determined using FTIR analysis. • The number of shells, carbon atoms, interlayer thickness are calculated by XRD. • The hydrogen desorption kinetics are investigated using Coat's-Redfern's method. [ABSTRACT FROM AUTHOR]

Plastic waste pyrolysis to clean energy (H 2) and valuable carbon nanotubes or nanofibers (CNTs/CNFs) is the most promising waste management and energy regeneration process. In this study, microwave-mediated single-step pyrolysis is used to produce COx-free hydrogen and CNTs/CNFs from real-world plastic films. Nickel, iron, and cobalt-based catalysts were prepared by the incipient wet-impregnation method and tested for real-world polyethylene plastic film degradation. In addition, the quality of CNTs produced and hydrogen yield were also compared for these catalysts. Various characterization tools were used to characterize the calcined catalysts, spent catalysts, and CNTs. Further, the effect of temperature ramp rate on hydrogen yield and CNTs properties was also analyzed. The results show that the iron-based catalyst produces a high yield of hydrogen and low-diameter and uniform-quality CNTs compared to other catalysts. [Display omitted] • The microwave was utilized for real-world waste plastic pyrolysis. • Transition metal-based alumina catalysts were used as microwave susceptors. • 10% Fe/Al 2 O 3 catalyst provides high selectivity towards hydrogen and CNTs. • Heating ramp rates do not affect the selectivity toward product distribution. [ABSTRACT FROM AUTHOR]

Herein, a novel multi-component electrocatalyst that integrates CuCo-MnO nanoparticles (NPs), carbon nanotubes and electrospun carbon nanofibers (CuCo-MnO@CNTs/CNFs) was prepared by combining electrospinning technology and an NH3 assisted graphitization process. The self-supported CuCo-MnO@CNTs/CNFs achieves impressive catalytic activity with overpotentials of 33 and 184 mV at 10 mA cm−2 for the HER, and 180 mV and 250 mV for the OER at 10 mA cm−2 in both acidic and alkaline solutions, respectively. [ABSTRACT FROM AUTHOR]

Stealth technology is used to enhance the survival of military equipment in the field of military surveillance, as it utilizes a combination of techniques to render itself undetectable by enemy radar systems. Radar absorbing materials (RAMs) are specialized materials used to reduce the reflection (or absorption) of radar signals to provide stealth capability, which is a core component of passive countermeasures in military applications. The properties of RAMs can be optimized by adjusting their composition, microstructure, and surface geometry. Carbon‐based materials present a promising approach for the fabrication of ultrathin, versatile, and high‐performance RAMs due to their large specific surface area, lightweight, excellent dielectric properties, high electrical conductivity, and stability under harsh conditions. This review begins with a brief history of stealth technology and an introduction to electromagnetic waves, radar systems, and radar absorbing materials. This is followed by a discussion of recent research progress in carbon‐based RAMs, including carbon blacks, carbon fibers, carbon nanotubes, graphite, graphene, and MXene, along with an in‐depth examination of the principles and strategies on electromagnetic attenuation characteristics. Hope this review will offer fresh perspectives on the design and fabrication of carbon‐based RAMs, thereby fostering a deeper fundamental understanding and promoting practical applications. [ABSTRACT FROM AUTHOR]

Nitrogen-doped carbon nanoribbons and nanotubes decorated with Co3O4 nanoparticles were prepared by a metal-catalyzed graphitization–nitridization and oxidization process, using triazole and melamine as a solid nitrogen/carbon co-source, and assessed as anodes of lithium ion batteries (LIBs). These composite anodes display perfect electrochemical performance, indicating their potential for application in LIBs. [ABSTRACT FROM AUTHOR]

Galvanostatic copper deposition is studied on two types of screen-printed electrodes (SPEs) coated with carbon nanofibers (CNF) or single-walled carbon nanotubes (SWCNT) in view of possible applications for electrochemical sensing of nitrate ions. It is found that the efficiency of the copper electrodeposition and the number and size of the obtained metal particles depend on the type of the carbon support. By varying the galvanostatic current and time the metal deposition is optimized in view of the use of the Cu-modified SPEs for nitrate reduction in slightly acidic solutions. It is demonstrated that under optimized conditions the Cu-modified CNF SPE shows better electrochemical stability and electroanalytical sensitivity for nitrate reduction than the Cu-modified SWCNT one. [ABSTRACT FROM AUTHOR]

With the continuous shrinkage of integrated circuit (IC) dimensions, traditional copper interconnect technology is gradually unable to meet the requirements for performance improvement. Carbon nanotubes have gained widespread attention and research as a potential alternative to copper, due to their excellent electrical and mechanical properties. Among various methods for producing carbon nanotubes, chemical vapor deposition (CVD) has the advantages of mild reaction conditions, low cost, and simple reaction operations, making it the most promising approach to achieve compatibility with integrated circuit manufacturing processes. Combined with through silicon via (TSV), direct application of CVD-grown carbon nanotubes in IC interconnects can be achieved. In this article, based on the above background, we focus on discussing some of the main challenges and developments in the application of CVD-grown carbon nanotubes in IC interconnects, including low-temperature CVD, metallicity enrichment, and contact resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • PdCl 2 precursor (PdCl) enhances electron-donation to Pd nanoparticles (NPs). • Carbon nanotubes (CNT) promote smaller Pd NPs and charge transfer to Pd NPs. • Small Pd NPs with high electron density favor selectivity to olefins and stability. • PdCl/CNT gives more than 80 % selectivity to olefins with H 2 /chloroform = 10. • Carbon nanofibers and Pd(NO 3) 2 favor bigger Pd NPs accelerating deactivation. The upgrading of wasted chloroform in hydrodechlorination for the production of olefins such as ethylene and propylene is studied by employing four catalysts (PdCl/CNT, PdCl/CNF, PdN/CNT, and PdN/CNF) prepared by different precursors (PdCl 2 and Pd(NO 3) 2) supported on carbon nanotubes (CNT) or carbon nanofibers (CNF). TEM and EXAFS-XANES results confirm that Pd nanoparticle size increases in the order: PdCl/CNT < PdCl/CNF ∼ PdN/CNT < PdN/CNF, descending the electron density of Pd nanoparticles in the same order. It illustrates that PdCl-based catalysts show donation of electrons from support to Pd nanoparticles, which is not observed in PdN-based catalysts. Moreover, this effect is more evident in CNT. The smallest and well-dispersed Pd nanoparticles (NPs) on PdCl/CNT with high electron density favor an excellent and stable activity and a remarkable selectivity to olefins. In contrast, the other three catalysts show lower selectivity to olefins and lower activities which suffer strong deactivation due to the formation of Pd carbides on their larger Pd nanoparticles with lower electron density, compared to PdCl/CNT. [ABSTRACT FROM AUTHOR]

The reaction of methane decomposition is an endothermic process that produces hydrogen without any impurities as a gas product and carbon nanotubes/carbon nanofibers as a solid product. In this study, NiO–MgO catalysts with different nickel loadings (20, 30, 40, and 50 wt. %) were synthesized using the mechanochemical method. The Physicochemical features of the synthesized catalysts were characterized by various methods such as BET, XRD, SEM, TPO, and H2-TPR. The prepared samples were tested in the methane decomposition process at various temperatures under the GHSV value of 48,000 ml/(gcat h). Among the prepared samples, the 50wt.%NiO–MgO exhibited the best activity (40% methane conversion at 575 °C) in this process due to its higher concentration of active metal and better catalyst reducibility. Also, the effect of different parameters such as feed ratio, GHSV, and calcination temperature was studied on the activity of this catalyst. The results showed that with the increase of GHSV and feed ratio, the methane conversion decreased due to the lesser contact time and diminishing the proportion of accessible active sites per methane entrance molecules. Moreover, the results showed that with the rise of calcination temperature from 500 to 700 °C, the methane conversion decreased due to the sintering of nickel particles. The results also showed that the addition of 15 wt.% Cr2O3 to the catalyst formulation improved the catalytic performance and lifetime in the thermocatalytic decomposition of methane due to the higher reducibility and dispersion of the active species on the catalyst surface. [ABSTRACT FROM AUTHOR]

Carbon materials with elusive 0D, 1D, 2D, and 3D nanostructures and high surface area provide certain emerging applications in electrocatalytic and photocatalytic CO2 utilization. Since carbon possesses high electrical conductivity, it expels the photogenerated electrons from the catalytic surface and can tune the photocatalytic activity in the visible-light region. However, the photocatalytic efficiency of pristine carbon is comparatively low due to the high recombination of photogenerated carriers. Thus, supporting carbon materials, such as graphene, CNTs (Carbon nanotubes), g-C3N4, MWCNs (Multiwall carbon nanotubes), conducting polymers, and its other simpler forms like activated carbon, nanofibers, nanosheets, and nanoparticles, are usually combined with other metal and non-metal nanocomposites to increase the CO2 absorption and conversion. In addition, carbon-based materials with transition metals and organometallic complexes are also commonly used as photocatalysts for CO2 reduction. This review focuses on developing efficient carbon-based nanomaterials for the photoconversion of CO2 into solar fuels. It is concluded that MWCNs are one of the most used materials as supporting materials for CO2 reduction. Due to the multi-layered morphology, multiple reflections will occur within the layers, thus enhancing light harvesting. In particular, stacked nanostructured hollow sphere morphologies can also help the metal doping from corroding. [ABSTRACT FROM AUTHOR]

Due to the advent of nanotechnology, deficiencies and limitations inherent in stimuli-responsive shape memory polymeric matrices (SMP), have been effectively mitigated, through the inclusion of a versatile range of organic or inorganic nanoparticulates within the confines of SMP matrice/s. This phenomenon has resulted in the emergence of shape-memory polymeric nanoarchitectures (SMPNs) possessing enhanced and outstanding properties, when compared with the pristine SMP, and this has subsequently enlarged their scope of applications (civil engineering, biomedical gadgets, aerospace, bionics engineering, energy, electronic engineering, household products, and textile engineering). Furthermore, SMPNs enhances athermal stimuli-activities including electroactivity, magneto-activity, water-activity, and photo-activity, as well as shape memory effect (SME) including multiple-shape memory effect (MSME), spatial shape memory effect (SSME), as well as dual-route shape memory effect (DRSME). This elucidation is essential and imperative at this time to enlighten the polymeric universe on new advancements in fabrication, features and applications of stimuli responsive SMPNs. Therefore, this paper, presents, very recently emerging advancements, in construction, characterization, properties and multifunctional applications of stimuli-responsive SMPNs with special emphasis on carbon nanotubes (CNT), carbon nanofibers (CNF), cellulose nanocrystals, and nanoclay reinforced SMPNs. [ABSTRACT FROM AUTHOR]

The application of composite materials as catalysts for the oxidation of CO and other toxic compounds is a promising approach for air purification. In this work, the composites comprising palladium and ceria components supported on multiwall carbon nanotubes, carbon nanofibers and Sibunit were studied in the reactions of CO and CH4 oxidation. The instrumental methods showed that the defective sites of carbon nanomaterials (CNMs) successfully stabilize the deposited components in a highly-dispersed state: PdO and CeO2 nanoparticles, subnanosized PdOx and PdxCe1−xO2−δ clusters with an amorphous structure, as well as single Pd and Ce atoms, are formed. It was shown that the reactant activation process occurs on palladium species with the participation of oxygen from the ceria lattice. The presence of interblock contacts between PdO and CeO2 nanoparticles has an important effect on oxygen transfer, which consequently affects the catalytic activity. The morphological features of the CNMs, as well as the defect structure, have a strong influence on the particle size and mutual stabilization of the deposited PdO and CeO2 components. The optimal combination of highly dispersed PdOx and PdxCe1−xO2−δ species, as well as PdO nanoparticles in the CNTs-based catalyst, makes it highly effective in both studied oxidation reactions. [ABSTRACT FROM AUTHOR]

Coal is a cheap and sustainable precursor for the preparation of fluorescent carbon nanomaterials (FCNMs). Based on the size and morphology, these nanomaterials are classified as carbon quantum dots (CQDs), carbon nanotubes (CNTs), carbon nanofibers (CNFs), carbon nanosheets (CNSs), graphene quantum dots (GQDs), carbon polymer dots (CPDs) etc. The FCNMs have sparked interest because of their distinctive fluorescence, effective catalysis, water solubility, biocompatibility, ease of surface functionalization, cost-effective synthesis, photostability, and other potential benefits for various advanced applications. A substantial percentage of the scientific community has been driven by a strong desire to prepare carbon nanomaterials (CNMs) using environmentally acceptable and low-cost synthesis methods. The precursors used in the preparation of carbon-based nanomaterials are critical to the technology's future success. Most traditional synthesis procedures use high-cost carbon feedstocks like hydrocarbons and graphite, limiting their commercialization. In this review, coal is used as starting material for the synthesis of FCNMs and is applied in various current fields. Highlights : • Coal and its derivatives derived fluorescent carbon nanomaterials are discussed. • Different type of methodology basically top-down and bottom-up for the preparation of fluorescent carbon nanomaterials are described. • The physical and optical properties of fluorescent carbon nanomaterials are discussed. • The origin of fluorescence on coal-based nanomaterials have been discussed. • The multifunctional applications of fluorescent carbon nanomaterials are summarized in detail. • The advantage, challenges and future prospects of fluorescent Carbon Nanomaterials from Coal is discussed. [ABSTRACT FROM AUTHOR]

Artificial muscle fibers driven electrothermally with excellent properties of response, stroke, and work capacity are expected to serve in some intelligent structures and systems. However, muscle fibers that operate in subzero environments are highly needed in industrial production and aerospace applications but remain challenging. Herein, we reported a coaxial artificial muscle fiber by electrospinning a sheath of polycaprolactone (PCL) nanofibers on the surface of a carbon nanotube (CNT) fiber core, achieving the actuation in response to thermal at subzero temperatures. The CNT@PCL coaxial muscle fiber under 0.3 MPa achieved a maximum contractile stroke of ~18% as the temperature changed from −130°C to 45°C. The actuation mechanism at subzero temperatures of this muscle fiber was analyzed in combination with the temperature-deformation schematic curve of different polymers. Furthermore, a temperature sensor based on this muscle fiber was developed, due to the excellent linear relationship between the contraction and temperature. A 3D-printed prosthetic arm was designed to further exhibit the application demonstrations of this muscle fiber in subzero environments. This work provides new insights into artificial muscle fibers for serving in extreme environments with ultralow temperatures. [ABSTRACT FROM AUTHOR]

Transition metal chalcogenides (TMCs) have been widely explored and utilized in sodium-ion battery (SIB) anodes owing to their unique advantages, such as high theoretical specific capacity and low cost. However, their inherent defects, such as low electronic conductivity and severe volume expansion, seriously limit the further development of TMC-based anodes. Here, a novel composite material of CoSe2 nanoparticles (NPs) encapsulated in a dual one-dimensional (1D) carbon composite structure (CoSe2@CNTs/N-CNFs) was designed deliberately. Carbon nanotubes (CNTs) were grown in situ on the surface of carbon nanofibers (CNFs) with eco-friendly ethanol as the carbon source, while electrospun polyacrylonitrile (PAN) fibers were pyrolyzed to form nitrogen-doped nanofibers. It is noted that the wrapping with the composite carbon structure greatly improved the stability of CoSe2 NPs and solved its inherent defects as an anode material. When assembled into a half-cell, the CoSe2@CNTs/N-CNFs electrode exhibited outstanding sodium storage performance with a reversible specific capacity of 442 mA h g−1 after 100 cycles at 0.1 A g−1, as well as excellent rate performance, and the discharge specific capacity still reached 265 mA h g−1 even after 2000 cycles at a high current density of 5 A g−1. This study shows a new way to build a novel carbon substrate and TMC composite sodium storage material with low cost. [ABSTRACT FROM AUTHOR]

Lithium–sulfur (Li–S) batteries have attracted great research attention because of their high energy density and low cost. However, shuttling effects of polysulfides and insulation from elemental sulfur hinder their practical application. Herein, we report hollow carbon nanofibers filled with carbon nanotubes (denoted as HCNF/CNT) as host materials for sulfur to mitigate the shuttling behavior and improve the kinetics of insulative sulfur. The as-prepared HCNF/CNT with nano-conductive domains in the hollow carbon nanofibers enables high loading and efficient utilization of sulfur. Owing to their unique structural superiority, the sulfur-encapsulated HCNF/CNT cathode materials for Li–S batteries deliver excellent electrochemical performance, including high specific capacity of 1156 mA h g−1 at 0.2 C, good rate performance and cycling stability with a capacity retention of 77.2% after 200 cycles at 2 C. Such a unique structure can provide inspiration for the rational structural design of carbon materials as hosts for high performance Li–S batteries. [ABSTRACT FROM AUTHOR]

Herein, highly transparent, flexible, and ultrathin piezocomposite, in which electrospun poly(vinylidene fluoride‐co‐trifluoroethylene) [P(VDF‐TrFE)] nanofibers (NFs) and aerosol‐synthesized single‐walled carbon nanotubes (SWCNTs) are embedded in elastomer matrix, is fabricated. The P(VDF‐TrFE) NF mat is exploited as a piezoelectric layer of the piezocomposite while the SWCNT film is applied as a transparent conductive electrode thereof. The use of these 1D nanomaterials allows the piezocomposite not only to be high transparency along with low diffusion of light (i.e., haze factor) but also to exhibit enhanced mechanical properties. In addition, the coupling effect of piezo‐ and flexoelectricity exhibited from the electrospun NFs and the acid‐doping effect conducted on the SWCNTs facilitates a significant improvement in kinetic energy‐harvesting performance, leading to a maximum output voltage of 26.8 V. Moreover, electrospinning and aerosol chemical vapor deposition methods employed here are facile, scalable, and cost‐effective, thus are expected to accelerate the development of industrially feasible next‐generation wearable electronics. [ABSTRACT FROM AUTHOR]

The need for cementation constructions and material usage has increased tremendously. However, finding the optimum mix and designing the required construction is challenging. Hence, the present research work has planned to design a novel fruit fly-based mix selection (FFbMS) for designing the carbon nanotube (CNT). Here, the mixes that have been considered to design the single-walled CNT are polyvinyl alcohol (PVA) microfibre, carbon nanofibre (CNF) and cement paste (CP). Initially, the mixes are selected based on the ASTM C 305 standard, and the casting process has been performed. Then, several optimization iterations were executed to find the optimal state by valuing the mechanical properties in each iteration. Moreover, based on the gained compressive rate, tensile strength and crack rate, the optimal value has been set, and the mix range has been noted. The temperature range for testing Thermal characteristics varied from 100 to 1000 °C. The gained maximum compressive strength by a novel FFbMS is 24 GPA, and the flexural strength is 6.9 MPa at 600 °C and 4.8 at 1000 °C, which is quite better than the conventional mixes. Finally, the performance score has been measured in five ways: CP, CP + CNF, CP + PVA, CP + CNF + PVA and optimal CP + CNF + PVA. Here, the optimal CP + CNF + PVA have recorded the finest performance outcome. The gained maximum compressive strength by a novel FFbMS is 24 GPA, and the flexural strength is 6.9 MPa at 600 °C and 4.8 at 1000 °C, which is quite better than the conventional mixes. [ABSTRACT FROM AUTHOR]

Carbon nanotubes/Carbon nanofibers (CNT/CNF), owing to their abundant active sites and high acidic resistance, have emerged as promising electrocatalysts for high-energy-density vanadium redox flow batteries (VRFB). However, the utilization of CNT/CNF has been obstructed owing to problems such as cost, and the detachment of CNT/CNF from the carbon electrode caused by the flowing electrolyte in VRFB. In this study, we proposed a novel strategy for uniformly implanted multiwall CNT in electrode materials such as graphite felt, for the development of efficient electron-networked electrodes. The weed root-like morphology of the electrode improved the charge transfer ability and minimized the increase in overpotential even after 1000 cycles of stability test. As a result, the electrode exhibited a high discharge capacity of 30.7 Ah·L−1 and an energy efficiency of 86.9%. Therefore, the proposed CNT implanted electrode can be used as an alternative design in practically feasible VRFB exhibiting sustainable electrochemical performance. [Display omitted] [ABSTRACT FROM AUTHOR]

The development of new scaffolds and materials for tissue engineering is a wide and open realm of material science. Among solutions, the use of biopolymers represents a particularly interesting area of study due to their great chemical complexity that enables creation of specific molecular architectures. However, biopolymers do not exhibit the properties required for direct application in tissue repair—such as mechanical and electrical properties—but they do show very attractive chemical functionalities which are difficult to produce through in vitro synthesis. The combination of biopolymers with nanostructured carbon fillers could represent a robust solution to enhance composite properties, producing composites with new and unique features, particularly relating to electronic conduction. In this paper, we provide a review of the field of carbonaceous nanostructure-containing biopolymer composites, limiting our investigation to tissue-engineering applications, and providing a complete overview of the recent and most outstanding achievements. [ABSTRACT FROM AUTHOR]

BACKGROUND: With the continuous progress and development of oral nanomaterials, a large number of studies have found that carbon nanomaterials are widely used in the field of oral implant.OBJECTIVE: To review the main classification, structural characteristics, osteogenesis, antibacterial, protein/drug carrier and related applications of carbon nanomaterials in oral implant. METHODS: After clarifying the classification of carbon nanomaterials, the Chinese search terms were “graphene/carbon nanotubes/Carbon Nanofibers/carbon nanomaterials, oral implant/osteogenesis and oral cavity/antibacterial and oral cavity/drug loaded and oral cavity”. English search terms were “Graphene/ carbon nanotubes/Carbon Nanofibers/carbon nanomaterials, dental implant/osteogenesis AND oral/ antibacterial AND oral/drug loaded AND oral”. The first author searched the relevant articles published from January 1998 to August 2021 in CNKI, Wanfang, VIP, and PubMed databases by computer. The search time limit of some classical articles was extended. Finally, 64 English articles and 9 Chinese articles were included according to the inclusion criteria. RESULTS AND CONCLUSION: (1) Carbon nanomaterials are mainly divided into three categories: zero dimensional, one-dimensional and two-dimensional carbon nanomaterials. Because of their unique spatial structure and good physical and chemical properties, they have a great application potential in implant surface coating, scaffold material modification, drug loading, and preparation of barrier membrane. (2) In addition, the osteogenic and antibacterial effects of the material are also conducive to the formation of stable bone integration and good soft tissue sealing. It also has certain research significance in the prevention and treatment of periimplant inflammation. (3) There are many kinds of carbon nanomaterials. Many studies also functionalize carbon nanomaterials and other biomolecular materials into composites, so that some properties can be obtained. In addition, carbon nanomaterials also have antibacterial effect, and graphene is often functionalized with other antibacterial agents (such as silver nanoparticles) to enhance antibacterial performance. (4) In general, graphene, as a typical two-dimensional carbon nanomaterial, has always been a research hotspot in oral implant and other fields. Graphene oxide is a widely used class of graphene derivative materials. It is found that when it is applied to implant surface modification, it has certain research significance in the treatment and prevention of periimplant inflammation. (5) However, the research on the signaling pathway and immune regulation mechanism of stem cell differentiation/osteogenesis induced by carbon nanomaterials is not clear, and the cytotoxicity, degradation and adverse reactions of materials still need to be further studied. (6) At present, a cost-effective, scalable and repeatable process for the preparation of carbon nanomaterials and the evaluation index of material biocompatibility need to be studied. In addition, it is also necessary to further study the significance of carbon nanomaterials in the prevention and treatment of periimplant inflammation when applied to implant surface coating. [ABSTRACT FROM AUTHOR]

A scheme for the full cycle of developing 3D products containing carbon nanostructures (CNSs) was developed. The scheme takes into account the state of initial carbon for the synthesis of CNSs and involves the preparation of CNSs for various 3D printing techniques (FDM, CJP, SLA, SLS) with post-processing of the printed 3D products. The developed cycle allows for the transformation of graphite or other carbon-containing materials into functional 3D products using a 3D printer. The 3D development cycle consists of three stages: Stage I is intended to select the starting material and method for CNS synthesis, Stage II involves preparation of CNSs as a consumable for 3D printing, and Stage III includes printing of a 3D product followed by post-processing. Each stage is described in detail and tested for each 3D printing technique (FDM, CJP, SLA, SLS). The entire range of CNSs (fullerenes and fullerene-like nanostructures, graphenes, carbon nanotubes (CNTs), carbon nanofibers (CNFs), nanocomposites, etc.) and their synthesis employing three methods (plasmaassisted chemical synthesis in gaseous and liquid environments and pyrolytic synthesis) in the 3D printing cycle were analyzed. The advantages and disadvantages of the considered 3D printing processes were addressed, and results of the comparison were summarized in a table. Materials for 3D printing and development of associated composites containing soluble and insoluble CNSs were studied. Methods for processing CNSs and preparing CNS-based composites prior to their use in various 3D printing processes were developed. The post-processing results for 3D products prepared with the FDM, CJP, SLA, and SLS 3D printing processes were provided. [ABSTRACT FROM AUTHOR]

The increasing resistance of bacteria and fungi to antibiotics is one of the health threats facing humanity. Of great importance is the development of new antibacterial agents or alternative approaches to reduce bacterial resistance to available antibacterial drugs. Due to the complexity of their properties, carbon nanomaterials (CNMs) may be of interest for a number of biomedical applications. One of the problems in studying the action of CNMs on microorganisms is the lack of universally standardized methods and criteria for assessing antibacterial and antifungal activity. In this work, using a unified methodology, a comparative study of the antimicrobial properties of the CNM systemic kit against common opportunistic microorganisms, namely Escherichia coli and Staphylococcus aureus, was carried out. Multiwalled carbon nanotubes (MWNTs), catalytic filamentous carbon with different orientations of graphene blocks (coaxial–conical and stacked, CFC), ionic carbon (OLC), and ultrafine explosive nanodiamonds (NDs) were used as a system set of CNMs. The highest antimicrobial activity was shown by NDs, both types of CFCs, and carboxylated hydrophilic MWCNTs. The SEM results point out the difference between the mechanisms of action of UDD and CFC nanotubes. [ABSTRACT FROM AUTHOR]

The specific geometry and distinct properties of one‐dimensional nanostructures make them the most ideal candidates as reinforcing elements in composites and the dependence of physical, mechanical, thermal, and wear properties of polymer composites on their dimensionality, nature, and dispersion is interesting. The upsurging demands for high‐performance elastomer composites require the application of such nanomaterials as reinforcing agents. Here, we offer a detailed characterization of some of the novel fibrous nanofillers such as silicon carbide nanofibers, aramid nanofibers, carbon nanotubes, and graphite nanofibers. Morphology, crystallinity, surface chemistry, polarity, and thermal stability of these nanofibers were analyzed using techniques such as electron microscopy, X‐ray diffraction, infrared and Raman spectroscopy, and thermogravimetric analysis. Natural Rubber nanocomposites were developed using these fibrous nanofillers, and their rheometric, mechanical, dynamic mechanical, and thermal properties were studied. ANF‐reinforced compounds gave the highest increment in 300% modulus while the highest tensile strength was obtained by CNT reinforced compounds at 4 phr filler loading. CNT and GNF‐reinforced compounds improved the wear resistance simultaneously by 43% and 33% respectively, while SiC and ANF improved it by 10% and 8% respectively. Lower tan delta and better thermal stability were also recorded. Future exploration may involve the use of these nanofibers in conjunction with carbon black or silica to achieve high‐performance elastomer compounds for real‐life applications. [ABSTRACT FROM AUTHOR]

The electrospinning technique was used to prepare nanofibers samples consisting of three groups, each group has a different polystyrene concentration (12, 14, 16 wt.%). Multiwalled carbon nanotubes were added to each group with four ratios to yield four samples comprising (polystyrene/MWCNT) constituents. The UV-Visible test was carried out to know how uniformly nanofibers and Mutli-walled carbon nanotubes were distributed in the polymeric nanofibers and their effect on the final nanofiber's properties through the absorption peaks. The morphological test used "Field Emission Scanning Electron Microscope". The results showed that; MWCNTS has a dominant effect on prepared nanofibers in the (12 wt.% Polystyrene) group, and both (PS, MWCNT) have a shared effect, highest steady absorption curves, and uniformly scattered radiation at (14 wt.% PS) group, and random results at (16 wt.% PS) group. From FESEM results we notice that increasing polymer concentration causes an increase in the nanofiber's diameter and beads formation chance increases at (12,16 wt.% PS) groups. In the group of (14 wt.% Polystyrene), it produces nanofibers with free beads and uniform distribution, the addition of MWCNT lowers the diameter of nanofibers much more and enhances the orientation, and improves their UV absorption, strength, and mechanical properties. [ABSTRACT FROM AUTHOR]

Herein, we propose novel, highly effective Pt-free counter electrode (CE) material for dye-sensitized solar cells (DSSC) based on the hierarchical carbon nanofibers/carbon nanotubes/NiCo (eCNF/CNT/NiCoNP) ternary nanocomposites. The materials were obtained by combining the electrospinning technique and CCVD synthesis of carbon nanotubes directly on the surface of eCNF. By using various conditions of the CNT growth, it was possible to obtain series of nanocomposites differing with their morphology, surface chemistry, and structural ordering. The conducted studies unraveled significant correlations between the disordering of the nanocomposites, and their electrocatalytic activity towards reduction of I 3 −. The investigation methods included i.a. SEM, TEM, XPS, UPS, EDS, XRD, SAED, CV, EIS and J-V characterizations. The counter electrodes based on the nanocomposite synthetized at the lowest CCVD temperature of 700 °C exhibited remarkable catalytical activity as evidenced by very low charge transfer resistance of 0.93 Ω cm2. Based on the obtained data, we propose new, alternative interpretation of the additional minor arc appearing at the high-frequency region of EIS Nyquist spectra of carbon based-CE. The DSSC with eCNF/CNT/NiCoNP-electrodes were characterized by efficiencies up to 7.08% (avg. η = 6.95%), which was higher than for Pt-based devices (avg. η = 6.80%), thus demonstrating excellent performance of prepared CE. Our results confirm that the eCNF/CNT/NiCoNP nanocomposite material is a promising low-cost CE alternative for DSSC. [Display omitted] • High catalytic activity of hierarchical carbon nanofibers/NiCoNP in I 3 −/I− redox. • Defects in CNT were majorly responsible for the enhanced activity of nanocomposites. • Temperature of CCVD controlled electrochemical performance of nanocomposites. • Minor hi-freq. EIS arc seems to originate from charge transfer at FTO/particle IF. • Hierarchical carbon nanocomposites are promising Pt-free counter electrode for DSSC. [ABSTRACT FROM AUTHOR]

The fabrication and design of carbon-based hierarchical structures with tailored nano-architectures have attracted the enormous attention of the materials science community due to their exceptional chemical and physical properties. The collective control of nano-objects, in terms of their dimensionality, orientation and size, is of paramount importance to expand the implementation of carbon nanomaterials across a large variety of applications. In this context, porous anodic alumina (PAA) has become an attractive template where the pore morphologies can be straightforwardly modulated. The synthesis of diverse carbon nanomaterials can be performed using PAA templates, such as carbon nanotubes (CNTs), carbon nanofibers (CNFs), and nanodiamonds, or can act as support for other carbon allotropes such as graphene and other carbon nanoforms. However, the successful growth of carbon nanomaterials within ordered PAA templates typically requires a series of stages involving the template fabrication, nanostructure growth and finally an etching or electrode metallization steps, which all encounter different challenges towards a nanodevice fabrication. The present review article describes the advantages and challenges associated with the fabrication of carbon materials in PAA based materials and aims to give a renewed momentum to this topic within the materials science community by providing an exhaustive overview of the current synthesis approaches and the most relevant applications based on PAA/Carbon nanostructures materials. Finally, the perspective and opportunities in the field are presented. [ABSTRACT FROM AUTHOR]

At present, carbon nanomaterials are widely used to improve the tribotechnical characteristics of various materials, including liquids. In the presented article, the issues of improving the tribotechnical characteristics of lubricating liquid media are considered. These liquids were modified with hybrid carbon materials, which are a mixture of graphite, graphene, and carbon nanotubes. Carbon mixtures of nanoparticles were obtained by the method of self-propagating high-temperature synthesis. It has been established that the introduction of mixtures of nanocarbon particles into a liquid lubricating medium significantly changes the tribological and viscosity characteristics. The most significant reductions in the values of the friction coefficient of modified liquids are observed at low concentrations of the carbon nanomodifier. [ABSTRACT FROM AUTHOR]

The combination of carbon nanotubes (CNTs) and graphene produce a CNTs-graphene hybrid material with excellent electrical and mechanical properties that improved from their single form. This CNTs-graphene hybrid material has the potential to be used as electrodes and interconnects as it has better properties compared to copper (Cu). This work intended to grow CNTs on graphene using a CVD technique. The growth process used graphene on a Cu substrate with ferrocene as the catalyst, acetone as the carbon precursor and reactor temperature of 800oC. However, the process has unintentionally grown carbon nanofibers (CNFs). To observe the progression in the growth of CNTs and CNFs on graphene, the effect of growth reaction time is crucial. Hence, this work investigates the growth progression of the CNTs and CNFs on graphene based on different reaction times of 10 min, 20 min, 30 min and 60 min. It was found that the agglomeration of carbon is incomplete at 10 min reaction time and produced cylindric nanostructures. A further reaction time of 20 min and 30 min has significantly changed the size of the cylindric nanostructures into CNTs and CNFs with a very slight difference in the size, density, and coverage. The 30 min reaction time produced denser CNTs and CNFs with more uniform size and coverages. A longer reaction time of 60 min led to very long CNFs with an average length of 120 µm. In conclusion, meticulous fine-tuning of the reaction time is required to control the formation of CNTs and CNFs on graphene. [ABSTRACT FROM AUTHOR]

Aceclofenac (ACL) is an anti-inflammatory drug, which is taken by patients who mainly suffer from rheumatoid conditions. In this work, we propose a new voltammetric method that allows the determination of ACL in pharmaceutics, urine, and plasma. As a working electrode, a glassy carbon electrode (GCE) modified with carbon nanofibers, carbon nanotubes, and NiCo nanoparticles (eCNF/CNT/NiCo-GCE) was used. The mentioned sensors are characterized by good repeatability and sensitivity, and their process of preparation is simple, fast, and cost-effective. Instrumental and method parameters were optimized, and the influence of interferences was investigated. To validate the analytical performance of the method, calibration was conducted. Good linearity was obtained (0.05–1.4 µM, r = 0.998), as well as excellent limit of detection (LOD) and limit of quantification (LOQ) values (0.7 nM and 2.1 nM, respectively). Calculated recoveries that were in the range of 98%–105% indicate that this method is accurate and might be used in routine laboratory practice. [ABSTRACT FROM AUTHOR]

In this paper, we present a number of novel pure-carbon structures generated from cyclo[18]carbon. Due to the very high reactivity of cyclo[18]carbon, it is possible to link these molecules together to form bigger molecular systems. In our studies, we generated new structures containing 18, 36 and 72 carbon atoms. They are of different shapes including ribbons, sheets and tubes. All these new structures were obtained in virtual reactions driven by external forces. For every reaction, the energy requirement was evaluated exactly when the corresponding transition state was found or it was estimated through our new approach. A small HOMO–LUMO gap in these nanostructures indicates easy excitations and the multiple bonds network indicates their high reactivity. Both of these factors suggest that some potential applications of the new nanostructures are as components of therapeutically active carbon quantum dots, terminal fragments of graphene or carbon nanotubes obtained after fracture or growing in situ in catalytic reactions leading to the formation of carbonaceous materials. [ABSTRACT FROM AUTHOR]

Polymeric nanocomposites of polystyrene nanofibers and multiwall carbon nanotubes and natural pigment were synthesized using electrospinning technique the polystyrene concentration was 12 wt.% and multiwall carbon nanotube was added by (0, 100, 140, 200 ppm), and natural pigment added by two drops (0.063 g) to the prepared solutions and many tests were carried out to the prepared solutions and the final samples. The solution tests included viscosity test by using cone-plate viscometer and surface tension test using du-nouy ring method. The nano textiles tests included the Fourier transform infrared spectroscope (FTIR) test, Field emission scanning electron microscopy (FESEM) test, contact angle test, and ultraviolet test to extract the energy bandgap using (tauc plot) method. The tests results showed that the viscosity increased by increasing the multiwall carbon nanotube and natural pigment and surface tension slightly increased at a high ratio of 200 ppm of multiwall carbon nanotube and natural pigment and physical type of reaction between the components were confirmed through FTIR, and the addition of multiwall carbon nanotube and natural pigment makes the fibers smoother and fewer beads formation and increase the multiwall carbon nanotube addition made the samples more hydrophobic and the charts of tauc plot show that increasing the MWCNT with natural pigment addition will increase the electrical sensitivity of the prepared samples in which the energy band gap dropped from 1.18 ev to 0.2 ev for the sample of Polystyrene/200 ppm MWCNT/natural pigment this is regarded as an indication of using it as a typical electrical sensor. [ABSTRACT FROM AUTHOR]

Summary: Combining a high‐capacity material possessing a core@shell structure with a carbon material is a powerful tactic for reinforcing the performance of Li‐ion battery (LIB) anodes. As an efficient and simple approach to obtain tin(II) sulfide (SnS) with ultrafast lithium‐storage capability and cycling stability, we propose the hierarchical core@shell structure of carbon nanofibers@SnS nanotubes (CNF@SnSNTs) covered with S‐doped carbon via a one‐pot carbonization by harnessing the Kirkendall effect of camphene and sulfurization of SnO2 by L‐cysteine. This hierarchical core@shell structure contains mesoporous carbon nanofibers (CNFs) that reduce the Li‐ion diffusion pathway, SnS nanotubes (NTs) that expand the active site, and a S‐doped carbon layer at the faces of the SnS NTs that promotes the electrical conductivity and inhibits volume expansion of SnS. Therefore, a CNF@SnSNT‐C7 electrode achieves superb ultrafast electrochemical performance (528.1 mAh/g under a current density of 2000 mA/g), high specific capacity (2218.2 mAh/g under a current density of 100 mA/g), and an ultrafast cycling stability of 92.9% after 500 cycles under a current density of 2000 mA/g. These performance improvements are resulted from the synergistical effect of mesoporous CNFs, SnS NTs, and S‐doped carbon layer. Therefore, CNF@SnSNT is potential anode material for LIBs having superior Li‐storage capability. [ABSTRACT FROM AUTHOR]

Microwave absorbers with light weight and excellent microwave absorption performance are urgently needed in the microwave absorption field, which is still a challenge. Herein, N-doped carbon nanofibers decorated with nickel nanoparticles (Ni@CNFs) were synthesized by a facile electrospinning method combined with a two-step heat treatment, in which Ni nanoparticles are uniformly dispersed in carbon nanofibers. Benefitting from the special nanoarchitecture (including Ni nanoparticles encapsulated with graphitic carbon layers and carbon nanotube protrusions anchored on CNFs), three-dimensional conductive networks, the synergistic effect between suitable impedance matching and satisfactory electromagnetic (EM) attenuation ability, a superb comprehensive microwave absorption (MA) property is achieved for the optimal Ni@CNF sample with a rather low filler loading of 5 wt%. The optimal reflection loss (RL) reaches −66.3 dB at a small thickness of 3.1 mm and the maximum effective absorption bandwidth (EAB, RL < −10.0 dB) as wide as 4.56 GHz is obtained at 2.0 mm. This study demonstrates that the carefully designed Ni@CNF composites are superior to many previously reported magnetic carbon-based hybrid absorbers and can be applied as promising candidates for light weight and high-efficiency EM wave absorbers. [ABSTRACT FROM AUTHOR]

The kinetics of the formation of carbon nanotubes on a catalyst during the pyrolysis of carbon-containing gases is rather peculiar and little studied. Its main provisions proposed in the literature are debatable. The complexity of studying the kinetics of NT synthesis is confirmed by the use of about 10 parameters when creating a model. The kinetic regularities of the formation of carbon nanotubes during the pyrolysis of methane are studied in terms of the yield of carbon at the optimal composition of the catalyst. [ABSTRACT FROM AUTHOR]

The mechanical mixtures of titanium oxide (TiO2) with carbon nanostructures for 3D printing of CJP technology, which are used as consumables for the manufacturing of electrically conductive composite 3D products, are created in this work. Various carbon nanostructures (single- and multi-walled carbon nanotubes and carbon nanofibers) were used in the creation of composite 3D products (TiO2-CNS) by CJP 3D printing technology. Optimal conditions for processing of mechanical mixtures (TiO2/MWCNT) on a planetary ball mixer for composite 3D products (CJP) were studied and proposed. The dose of the deformation influence on the mechanical mixture under optimal conditions of mechanochemical processing (76 J/g), which allows not to deteriorate the electrical conductivity of the material, is determined. The dependence of the electrical conductivity of composite 3D products (CNS/TiO2, where the CNS content is 3 wt. %) on the type of carbon nanostructures (SWCNT, MWCNT and CNF) contained in ceramics (TiO2), is constructed. The exponential dependence of the specific electrical conductivity (G) of composite 3D products (TiO2-MWCNT) on the mass content of multi-walled carbon nanotubes, is also recorded in the work. In the framework of the study of the electrical conductivity of composite 3D products (CJP), a fuel cell cathode based on a Pt/TiO2-MWCNT composite was created. It was found that the catalyst Pt/TiO2-MWCNT, which contains 5 wt. % of carbon nanotubes, has the best catalytic activity in oxygen recovery. At the same time, the average particle size of platinum (Pt) is 5-10 nm, while the content of Pt in the EDX samples is approximately ~10 wt. %. Also, studies were carried out from the mixing of Pt/TiO2-MWCNT composites with MWCNT content 15 and 50 wt. %. Samples were analyzed by transmission and scanning electron microscopy. [ABSTRACT FROM AUTHOR]