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This study evaluated the effect of multi‐walled carbon nanotubes (MWCNT) addition on the thermomechanical, and electrical responses of unidirectional flax fibers/Elium acrylic modified carbon nanotubes‐based composite. The manufacturing process of these laminated composites involved infusing the nanofillers onto the fibers, ensuring good dispersion of MWCNT within the matrix. Regardless of the rate of incorporated nanotubes, this study revealed a significant deterioration of the mechanical properties in tension and viscoelastic properties of the Elium acrylic resin‐based nanocomposite. The electrical conductivity significantly increased for all nanocomposites and laminated composites. In contrast to the nanocomposite, the unidirectional flax fibers/MWCNT/Elium acrylic composite exhibited a considerable improvement in mechanical properties. An increase in Young's modulus and stress at break of about 27% and 23% respectively, was achieved for the material loaded with 2 wt% of MWCNT. The presence of MWCNT reduces the saturation weight by 5% for the unidirectional composite filled with an amount of 1.5 wt% in MWCNT. Highlights: Improving the electrical properties of nanocomposites and unidirectional fibers (UD) composites.Improving the mechanical properties of Elium/flax/multi‐walled carbon nanotubes (MWCNT) composites.Influence of MWCNTs on the water absorption of UD composites.Influence of MWCNT on the glass transition temperature of nanocomposites.Inhibiting polymerization of MWCNT with Elium. [ABSTRACT FROM AUTHOR]

In this work, a novel approach is taken to enhance the thermal conductivity and mechanical properties of composites by developing highly efficient thermally conductive PVDF‐based composites. This is developed by incorporating tetra‐pod zinc oxide whiskers (T‐ZnOw) in conjunction with multiwalled carbon nanotubes (MWCNT) to form binary hybrid fillers within a polyvinylidene fluoride (PVDF) matrix. Polydopamine (PDA), characterized by physical adsorption, is selected for surface coating on T‐ZnOw since T‐ZnOw is easy to self‐agglomerate and difficult to modify by physical and chemical methods. The coating aims to improve the dispersibility of T‐ZnOw and reduce the interfacial thermal resistance with the substrate. MWCNT is oxidized to improve its dispersion ability while strengthening the interaction with the matrix, due to the absence of interaction between MWCNTs and polymer matrix and poor dispersibility with the matrix. The dispersity of PDA@T‐ZnOw and o‐MWCNT is improved, and the three‐dimensional hybrid network structure can be better constructed to improve the thermal conductivity of the composite membrane. At a filler content of 25 wt%, the thermal conductivity reaches 0.302 W m−1 K−1 for T‐ZnOw–MWCNT–PVDF and 0.222 W m−1 K−1 for PDA@T‐ZnOw–o‐MWCNT–PVDF. [ABSTRACT FROM AUTHOR]

In order to explore the micro‐pore structure improvement mechanism of multi‐walled carbon nanotubes (MWCNT) on the frost resistance of concrete, five kinds of MWCNT concrete with different contents were prepared and the frost resistance test and mercury intrusion test were carried out. The results show that when the content of MWCNT is 0.1 wt%, the mass loss rate and compressive strength loss rate of concrete after freezing and thawing are 15.97% and 23.85% lower than that of ordinary concrete, respectively, indicating that this content is best amount to improve the frost resistance of concrete in this study. Moreover, 0.1 wt% MWCNT can significantly optimize the internal pore structure of concrete, and the average pore diameter growth rate and harmful pore ratio are 30.1% and 64.45%, respectively, after 200 freeze–thaw cycles. The proportion of more harmful pores has the greatest influence on compressive strength and relative elastic modulus, and the gray correlation degree is more than 0.8. Finally, the mathematical models of compressive strength‐pore parameters and relative dynamic elastic modulus‐pore parameters of MWCNT concrete after freeze–thaw cycle are established considering pore structure parameters and pore size distribution. [ABSTRACT FROM AUTHOR]

The synthesis of gold nanoparticles reinforced functionalized single‐walled/multi‐walled carbon nanotubes nanohybrid based polyaniline nanocomposites were carried out using in situ polymerization. The chemical interaction and nanostructured morphology of the synthesized nanocomposites are studied using ultraviolet–visible spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, x‐ray diffraction analysis, x‐ray photoelectron spectroscopy, and field emission scanning electron microscopy. Thermal stability of synthesized PANI/Au@f‐SWNTs is boosted by a magnitude of 30°C as compared with the pristine PANI matrix, which is attributed to a strong barrier effect because of the development of tortuous path that resulted from a uniform distribution of Au@f‐CNTs throughout the PANI matrix. For PANI/Au@f‐SWNTs, the AC conductivity and dielectric permittivity are improved by a value of 83.58 S/cm and 1.35 × 10−5 as well as the dielectric loss is reduced by a factor of 0.11 in comparison with the pure PANI matrix at an applied frequency of 106 Hz. PANI/Au@f‐SWNTs and PANI/Au@f‐MWNTs ternary nanocomposites exhibited excellent selectivity toward the hazardous Cr(VI) heavy metal ions in an aqueous medium with a limit of detection of 0.74 and 0.89 μM with a binding constant of 1.028 × 105 and 3.46 × 104 M−1, respectively, that can be selective and sensitive for the detection of Cr(VI) metal ions in water at trace level. [ABSTRACT FROM AUTHOR]

In this work, new nanoadsorbents consisting of polymer‐modified multi‐walled carbon nanotubes (MWCNTs) were used to remove toxic ionic dyes, of methylene blue (MB) and methyl orange (MO), effectively from aqueous solutions. The MWCNTs were coated with polymer brushes of poly(potassium 3‐sulfopropyl methacrylate) (PKSPMA) and poly(2‐methacryloyloxyethyltrimethylammonium chloride) (PMETAC) via surface‐initiated atom transfer‐radical polymerization. The PKSPMA@MWCNTs and PMETAC@MWCNTs delivered removal efficiencies of ~80% at pH 7. Maximum adsorption capacity (qmax) reached 411.62 mg/g for MB using PKSPMA@MWCNTs and 224.60 mg/g for MO using PMETAC@MWCNTs, showcasing the effectiveness of these novel nanoadsorbents. The experimental results were analyzed using adsorption isotherm models (Langmuir, Freundlich, and Temkin) and kinetic models (pseudo‐first‐order, pseudo‐second‐order, and intraparticle diffusion). The Freundlich model provided an excellent fit for MB adsorption on both adsorbents, whereas the Temkin model best described MO adsorption on PKSPMA@MWCNTs and the Langmuir model on PMETAC@MWCNTs. The fitting results showed that the pseudo‐second‐order kinetic model was the most accurate fit for MB and MO adsorption on both nanoadsorbents, suggesting that the removal mechanism was chemisorption. In conclusion, PKSPMA@MWCNTs and PMETAC@MWCNTs demonstrate significant potential as effective adsorbents for dye removal from water, providing a promising approach for water treatment and environmental remediation. [ABSTRACT FROM AUTHOR]

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

Mechanical and electromagnetic interference (EMI) shielding properties are investigated for developed synthesized green composite. The varying content of kenaf fiber‐reinforced high‐density polyethylene (HDPE) composite has been fabricated using microwave‐assisted compression molding techniques with and without the addition of multi‐walled carbon nanotubes (MWCNTs). X band range has been used for EMI shielding characterization. Optimization for mechanical strength has been done using tensile test, impact test, and translaminar fracture toughness test. Fractography by scanning electron and optical microscopy concluded that interfacial adhesion between kenaf fiber and HDPE matrix and the degree of ductility of the matrix are primary governing factors for change in mechanical properties. The differential scanning calorimetry confirmed no change in the degree of crystallization of the matrix with the addition of MWCNTs. Composite with EMI shielding effect above 30 dB along with superior mechanical properties is obtained at 16% (v/v) kenaf fiber content with the addition of 5% (wt.) conductive MWCNTs for possible application in electronic equipment casing, overhead bin, or unmanned aerial vehicles. [ABSTRACT FROM AUTHOR]

BACKGROUND: Biogenic amines (BAs) in high concentrations are toxic and may cause a series of health symptoms. A sensitive measurement of BA levels is essential for human health. Capillary electrophoresis (CE) has emerged for the separation of eight BAs due to simple sample preparation and highly efficient separation. However, an important drawback for CE is low sensitivity. Magnetic solid‐phase extraction (MSPE) has become a technique of interest owing to its brief operation and low solvent consumption. Hence, MSPE as a pretreatment has great potential to improve CE sensitivity for the analysis of BAs in complex food. RESULTS: Results showed that the Pt‐Co‐MWCNTs‐COOH possessed strong magnetism, good reusability, and high adsorptive ability toward eight biogenic amines based on the hydrogen bonding between the −COOH of Pt‐Co‐MWCNTs‐COOH and −NH2 groups of BAs. Using it as an adsorbent, a magnetic solid‐phase extraction coupled with capillary electrophoresis (MSPE‐CE) method was developed to effectively extract and sensitively analyze eight BAs. Under optimal conditions, the MSPE‐CE method has wide linearities (10.0–1000.0 μg L−1) and low limits of detection (1.0–6.1 μg L−1). The accuracy of the developed method yielded recovery values from 82.07% to 102.58%. Meanwhile, the BAs contents in two samples were analyzed using the MSPE‐CE method, with the results consistent with those detected by a high‐performance liquid chromatography method. CONCLUSION: Given those advantages, the established MSPE‐CE method promises the practical guidance of monitoring a variety of BAs and provides a foundation for the detection of other food hazards. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Diazepam (DZP), a long‐lasting benzodiazepine and controlled substance, is prevalent on the illegal market, notably as a date rape drug. This study presents a novel electrochemical sensor (CPE/GCPE/MWCNTs) for DZP determination in lab routines. Characterized through LSV, EIS, and SEM, the sensor revealed a pH‐dependent, irreversible reduction process at approximately −0.70 V (vs. Ag/AgCl(sat)). Optimization with SWV and 0.1 mol L−1 B–R solution (pH 1.0) produced a calibration curve spanning 1.49 to 21.5 μmol L−1. LOD and LOQ were 0.33 and 1.10 μmol L−1, respectively. Quantification in spiked samples exhibited no significant differences compared to HPLC‐DAD, endorsing the sensor for monitoring date rape drugs in forensic analysis. [ABSTRACT FROM AUTHOR]

This work describes the synthesis of novel nickel tetra substituted 6‐bromobenzothiazole carboxamide nickel (II) phthalocyanine (NiTBBTCAPc) and confirmed by spectroscopic‐microscopic methods and as well as electrochemical analysis. The electrochemical oxidation of nitrite was studied on NiTBBTCAPc‐multiwalled carbon nanotube (MWCNTs)/glassy carbon electrode (GCE) due to its better electron transferring ability than bare GCE and NiTBBTCAPc/GCE. As there is acceleration in surface area of GCE by multiwalled carbon nanotubes, a cyclic voltammetry (CV), differential pulse voltammetry (DPV), and amperometric techniques utilized for nitrite sensor were developed. The sensor exhibited a fast response towards nitrite with a detection limit of 3.012 nM and a linear concentration range of 50–900 nM by the CV method. The fabricated sensor shows excellent electrocatalytic activity compared with the modified electrode with Pc with a composite of MWCNTs towards oxidation of nitrite. The NiTBBTCAPc‐MWCNTs/GCE shows good repeatability, stability, and high selectivity even in the presence of excess ascorbic acid (AA), dopamine (DA), uric acid (UA), paracetamol (PA), glucose, Pb (II), Cd (II), Ca (II), and Mg (II). Finally, for usage in practical applications, the modified electrode was employed to achieve quantitative detection of nitrite in drinking water and cabbage vegetable samples, respectively. [ABSTRACT FROM AUTHOR]

The present study was an attempt to improve the toughness, mechanical and adhesion properties, and thermal stability of a two‐phase epoxy DGEBA/Resole phenolic resin through the use of carboxyl‐modified multi‐walled carbon nanotubes (c‐MWCNTs) and ground rubber tire (GRT) powder. The effect of a hybrid reinforcement containing GRT and c‐MWCNT blend on the mechanical properties, thermal stability, and microstructure of the epoxy‐phenolic adhesive were evaluated by tensile test, TGA, and FESEM, respectively. The formulated adhesive was utilized in a lap joint metal to a composite in order to peruse the adhesion features, where the composite was an epoxy resin reinforced with carbon fibers and the metal was stainless steel 316 L. According to the tensile test, there were 32% rise in tensile strength, 27% rise in modulus, and a 64% rise in toughness with adding 0.5% wt c‐MWCNTs and 15 phr waste GRT powder to the epoxy‐phenolic matrix. Furthermore, adding 1% wt c‐MWCNTs of nanoparticles and GRT powder has resulted in a 15% increase in lap shear strength. It also can be seen that thermal stability for the formulated samples has experienced an upward trend compared to the neat epoxy composite. Highlights: Epoxy adhesives based on GRT Powder, c‐MWCNTs particles and phenolic resin have been successfully prepared.The hybrid uses of GRT Powder and c‐MWCNTs particles can synergistically increase the tensile and lap shear strengthThe addition of c‐MWCNT nano particles and GRT Powder in an epoxy adhesive can have a dramatic rise in the toughness system compared to the neat epoxy adhesive.Maximum degradation temperature of the produced newly adhesive has increased considerably in contrast with the neat epoxy adhesive. [ABSTRACT FROM AUTHOR]

This article reports the quantitative effect on carbon nanotubes (CNTs), which are exposed to low‐temperature plasma, for the purpose of a filler application of polyurethane (PU) composite. The plasma exposure provides an opportunity for the surface modification of the CNTs, so the exposure possibly enhances the interfacial interaction in PU composite. In this article, we carried out a wear‐resistant examination to investigate the mechanical property of the PU composite with plasma‐treated CNTs with a variation of the CNT concentration in the PU composite. Our results showed that plasma treatment assisted the resistance of the PU composite. Furthermore, our observation showed that plasma treatment gives a good dispersion in the composite and possibly enhances interfacial interaction due to surface modification. [ABSTRACT FROM AUTHOR]

Dopamine (DA) plays an essential role in the central nervous, renal, hormonal and cardiovascular systems. Various modified carbon nanotubes (CNT)‐based dopamine sensors have been reported, but inexpensive, highly sensitive plain CNT‐based ones are seldom studied. In this work, a facile and inexpensive CNT‐based DA sensor is made by rich‐defect multi‐walled carbon nanotubes (RD‐CNT) via an ultrasound method. The defect and elemental states of the RD‐CNT are systematically studied by transmission electron microscopy (TEM), high‐resolution transmission electron microscopy (HR‐TEM), Raman spectroscopy, X‐ray powder diffraction (XRD) and X‐ray‐photoelectron spectroscopy (XPS). Results show that massive holes and cracks exist in RD‐CNT. The level of defects increases from the additional exposed edges. The electrochemical characterizations indicate that the electrochemical sensor has the highest sensitivity of 438.4 μA/(μM ⋅ cm2) among all carbon materials‐based DA sensors while well meeting the clinically required detection range and selectivity. The DA sensor was further used to detect live healthy human serum and live PC12 cells with satisfactory results, thus holding great promise for an inexpensive but sensitive DA sensor in practical applications of clinical diagnosis and biological research. [ABSTRACT FROM AUTHOR]

An ultra‐high‐performance liquid chromatography‐tandem mass spectrometry method was developed for simultaneous determination of 10 kinds of aminoglycosides in edible parts of aquatic products. The samples were extracted with 10 mmol/L potassium dihydrogen phosphate buffer solution, then the pH value of the extract was adjusted to neutral by sodium hydroxide. Half volume of the extract was loaded onto multiwalled carbon nanotubes cartridge. All the target compounds were separated on a mixed‐mode ion exchange column and detected by ultra‐high‐performance liquid chromatography‐tandem mass spectrometry with electrospray in the positive ionization mode. Under optimized conditions, this method had a good linearity with a squared correlation coefficient > 0.999. For neomycin, the limit of detection and limit of quantification were 5.0 μg/kg and 10.0 μg/kg, respectively; for hygromycin B and apramycin, values were 2.0 μg/kg and 5.0 μg/kg, respectively; for the other seven kinds of aminoglycosides, values were 1.0 μg/kg and 2.0 μg/kg, respectively. The average recoveries presented 75.8%–107.2% with intra‐ and interday reproducibility ranging between 3.8% and 12.5%. The method was rapid with good separation and sharp peak shapes, had the characteristicsis of high accuracy and good precision, and was suitable for simultaneous determination of 10 kinds of aminoglycosides in aquatic products. [ABSTRACT FROM AUTHOR]

Metallopolymers (MEPEs) show a strong absorption band attributed to a metal‐to‐ligand charge transfer (MLCT) transition. Fe‐MEPE and Ru‐MEPE thin films switch reversibly from blue‐purple (λmax=584 nm, Fe2+) to colorless (Fe3+) or orange (λmax=518 nm, Ru2+) to pale green (Ru3+). The addition of multi‐walled carbon nanotubes (MWCNTs) enhances the electrochromic (EC) properties of Fe‐ and Ru‐MEPE electrodes in several ways: (1) faster response for bleaching/coloring; (2) enhanced Coulombic efficiency; and (3) improved cycling stability, particularly for Ru‐MEPE. Moreover, the charge density of the thin film electrodes can be increased upon the addition of the MWCNTs. This performance improvement is demonstrated in electrochromic devices (ECDs) with titanium‐doped vanadium oxide (TiVOx) as the optically‐passive ion storage layer. The visible light transmittance τv values of the ECDs are improved by the addition of the MWCNTs from 20 %/56 % to 17 %/56 % and from 31 %/47 % and 34 %/55 % in the dark/bright state, for Fe‐MEPE and Ru‐MEPE, respectively. Thus, the addition of MWCNTs to Fe‐ or Ru‐MEPE is a very promising route for future fast‐switching EC applications, e. g., displays, sunroofs, and rear‐view mirrors. [ABSTRACT FROM AUTHOR]

Although a high figure of merit (zT) over a wide range of temperatures has been shown in n‐type Zintl Mg3(Sb, Bi)2, further improvement of its near‐room‐temperature performance is still required to promote its application in next‐generation thermoelectric coolers and power generators. Here, a novel strategy of phonon spectra mismatch for enhancing the thermoelectric performance of Mg3(Sb, Bi)2 is reported by incorporating multi‐walled carbon nanotubes (MWCNT). The introduction of very small amounts of MWCNT generates a large interfacial thermal resistance and thus significantly reduces the lattice thermal conductivity of the resulting composites, while maintaining a high power factor. As a result, a zT of ≈1.5 at 573 K and an average zT of 1.14 between 323 and 573 K can be achieved in the 0.5 wt% MWCNT composite. Moreover, a high conversion efficiency of ≈8.1% under a temperature difference of 283 K is realized in a resulting single‐leg device, making it a promising candidate material for low‐grade heat recovery. This study provides not only a material with a high near‐room‐temperature zT but also a unique insight into the design of high‐performance thermoelectric materials via compositing to exploit the large difference in phonon spectra between the components of the composite. [ABSTRACT FROM AUTHOR]

In this study, we investigated the performance and elucidated the synergistic effects of microalgae–fungi symbionts co‐cultured with 10−7 and 10−9 mol L−1 of GR24 and supplemented with endophytic bacteria, multi‐walled carbon nanotubes (MWCNTs) or vitamin B12 (VB12), on nutrient removal and biogas upgrading. The results showed that the microalgae–fungi–bacteria symbiotic system co‐cultured with 10−9 mol L−1 GR24 presented the optimal growth performance of 0.368 ± 0.04 d−1, chlorophyll a of 249.36 ± 22.31 μg L−1, and extracellular carbonic anhydrase activity of 42.55 ± 3.755 enzyme units. In this co‐culture system, the organic matter, nutrients, and CO2 purification obtained the highest removal efficiency, with 81.35 ± 7.96% for chemical oxygen demand, 83.56 ± 7.91% total nitrogen, 84.17 ± 7.95% total phosphorus, and 63.72 ± 6.06% CO2. The symbiont system also greatly increased the methane content in the biogas by 30.67%. The remarkable performance of the microalgae–fungi–bacteria symbiotic system shows its ability to be broadly applied in simultaneous biogas upgrading and wastewater treatment. Practitioner Points: The optimal GR24 concentration for microalgae–fungi consortia was 10−9 M.Endophytic bacteria were superior to MWCNTs and VB12.Fungi–algae–bacteria consortia presented excellent growth and removal performance.Removal efficiencies of COD, TN, and TP were about 81% under optimum treatment. [ABSTRACT FROM AUTHOR]

Here, we report multiwalled carbon nanotubes (MWCNTs) functionalized with γ‐cyclodextrins (γCD) as a novel electrochemical strategy for Rutin determination, showing superior performance than β‐cyclodextrins (βCD) modified MWCNTs, suggesting an adequate environment for host‐guest interactions. Under optimized conditions, the sensor showed a linear range of 39–975 nmol L−1 and a limit of detection of 7 nmol L−1. When tested with quercetin, catechin, and caffeine, the platform presented high selectivity with an interference response <10 %. The method was employed to quantify Rutin in spiked pharmaceutical and herbal extracts, providing recovery of 93–98.4 %. Also, HPLC‐PDA confirmed the method's accuracy. [ABSTRACT FROM AUTHOR]

To reveal a relationship among crystallization, conductivity and electromagnetic shielding properties of full biodegradable polymer after ultraviolet (UV) aging, polybutylene succinate (PBS)‐based composites with different weight ratios of multi‐wall carbon nanotubes (MWCNTs)/polylactic acid (PLA) /PBS masterbatch were processed via melt‐compounding approach. Morphology of the MWCNTs/PLA/PBS masterbatch prepared by Pickering emulsion method was confirmed by scanning electron microscope (SEM) and transmission electron microscope (TEM) observation. Comprehensive effects of different content of masterbatch and UV aging time on the morphology, crystallization, and electrical and electromagnetic shielding properties of MWCNTs/PLA/PBS composites were shown by Fourier transform infrared spectroscopy (FTIR), SEM, wide angle X‐ray diffraction (WAXD), differential scanning calorimeter (DSC), polarizing microscope (POM), ultra‐depth of field optical microscope, resistance tester, and vector network analyzer. Compared with PBS composite with 0.1 wt% MWCNTs, the electrical conductivity of PBS composite with the MWCNTs/PLA/PBS masterbatch increased by two orders of magnitude, and dispersed morphology for the composite showed double percolation structure. After UV aging, both MWCNTs/PBS composites and the PBS composites with the MWCNTs/PLA/PBS masterbatch, their surface presented burnt yellow and parts of flaws, while both their electrical conductivity and total electromagnetic shielding effectiveness gradually increased. Moreover, with the increasing of UV aging time, not only crystal size of these PBS‐based composites became large, but also their crystal interface became clearer. Furthermore, when UV aging time reached 528 h, the tensile strength of 0.6 M/PLA/PBS composite decreased by 12.6%, while its total electromagnetic shielding effectiveness increased by 39.8%, compared with the composite without UV aging. [ABSTRACT FROM AUTHOR]

The rapid growth in traffic volume and loads has increased the demand for high strength and durability paving materials. As the primary paving material of long‐life pavements and long‐span steel bridge decks, epoxy asphalt (EA) has the problems of poor tensile strength and low fracture toughness. In this study, graphene oxide nanosheets (GOs) and multiwalled carbon nanotubes (CNTs) were used to improve the mechanical properties of EA. Tensile tests, segregation experiments, Fourier transform infrared analysis, X‐ray diffraction, and fluorescence microscope (FM) were used to analyze the mechanical properties and micromorphology of nano‐modified EA, and to explore the optimal content of these two nano‐modifiers in EA. The results of tensile properties tests show the tensile properties of advanced nano‐modified EA are better when 0.01 wt% CNTs and 0.02 wt% GOs are added. Among them, EA modified by CNTs has the best toughening effect, and its fracture toughness is increased by 21%. Finally, combining macroscopic and microscopic experimental analysis, it is concluded that the mechanical homogeneity of the advanced nano‐modified EA is better, and the asphalt is uniformly dispersed in the continuous phase of epoxy resin. Furthermore, CNTs are chemically reacted with the amino group in oleylamine and modified EA through fiber network reinforcement, and GOs modified EA through the amidation reaction with oleylamine. [ABSTRACT FROM AUTHOR]

Carbon‐based nanomaterials are renowned for their exceptional properties, making them propitious candidates for oxygen reduction reaction (ORR) electrocatalysis. However, their intrinsic activity is often challenging to investigate unambiguously with conventional methodologies due to the inherent complexities of such systems and the material itself. Zooming into the material and gaining electrochemical information with high resolution is a way to get rid of many experimental factors that influence the catalytic activity in macro‐scale measurements. Herein, we employ nano‐scale scanning electrochemical cell microscopy (SECCM) to investigate individual catalyst agglomerates with and without Nafion content. The intrinsic ORR activity of the catalyst was unravelled by using a unique approach of normalizing the data of all measured points by their distinctive electrochemical surface area (ECSA). When coupling with scanning electron microscopy (SEM), the structure and morphology of the catalytically active agglomerates were visualized. [ABSTRACT FROM AUTHOR]

Herein, pre-dispersed ball-milling and space-holder methods are used to prepare carbon nanotubes (CNTs) reinforced aluminum (Al) matrix composite foams (C-AMCFs). Systematic research is conducted on the mechanical and electromagnetic shielding properties of C-AMCFs as well as the optimal ball-milling time. The results demonstrate a quasi-linear relationship between CNTs contents and optimal ball-milling time. With the addition of CNTs, the compressive performances of C-AMCFs first increase and subsequently decrease. The 2.5 wt% C-AMCFs have the best mechanical performance, whose yield strength (19.25MPa), plateau stress (20.87MPa), and energy absorption capacity (8.874 MJm-3), are both 1.72, 1.72, and 1.79 times than those of AFs, respectively. In the X-band (8.2-12.4GHz), the addition of CNTs in C-AMCFs can increase their electromagnetic shielding effectiveness. The greatest electromagnetic shielding effectiveness of the 2.0 wt% C-AMCFs is 30-40 dB. By enhancing the reflection loss at the first interface as well as the absorption and reflection loss inside the cell walls, CNTs play an important role in improving the electromagnetic shielding performance of C-AMCFs. [ABSTRACT FROM AUTHOR]

As a typical plant hormone, indole‐3‐acetic acid (IAA) can regulate the biological activities including division, growth and differentiation of plant cells. In this paper, a MXene and multi‐walled carbon nanotubes composite was prepared by self‐assembly procedure, which was modified on screen‐printed electrode (SPE) to construct a wireless portable electrochemical sensor. Electrochemical investigations of IAA were studied by cyclic voltammetry and an irreversible oxidation process could be observed. The excellent electroanalytical method of IAA was realized on the modified SPE with the detection range as 0.05–125.0 μmol/L and the detection limit as 16.7 nmol/L. The sensor was used for IAA content analysis in different part of pea seedlings with satisfactory results. [ABSTRACT FROM AUTHOR]

In this paper, novel embolic microspheres with efficient drug delivery and slow drug release properties were developed, which have potential applications in transarterial chemoembolization (TACE). The microspheres were prepared by suspension polymerization using vinyl acetate, 10‐Undecen‐1‐ol (UO), multi‐walled carbon nanotubes, and crosslinking agent (1,4‐butanediol divinyl ether). In the process, porous titanium tubes are used to control the particle size of the microspheres. In addition, the introduction of long‐chain (UO) makes the microsphere good swelling property in acetone. Multi‐walled carbon nanotubes modified by hexadecyltrimethoxysilane (HDTMS) are helpful for increasing both spherical morphology stabilization and swelling properties in acetone as well (C‐PVA‐2UO/CNT). Target drug was dissolved in acetone and the mcirospheres were dispersed in acetone to realize drug load. In vitro biocompatibility analysis showed that C‐PVA‐2UO/CNT is non‐cytotoxic and hemocompatible. The sustained drug release properties of C‐PVA‐2UO/CNT were confirmed by drug indomethacin (IMC) loading and release experiments. These findings suggest that the newly developed C‐PVA‐2UO/CNT has great potential to be used as a drug‐loaded embolization agent. [ABSTRACT FROM AUTHOR]

This work reports an electrochemical sensing framework for nicotine determination based on glassy carbon electrode (GC) immobilized with Fe(bpy)32+ (where bpy is 2,2'‐bipyridyl) supported by Nafion and multi‐walled carbon nanotubes (Nf‐MWCNTs). Fe(bpy)32+ immobilized Nf‐MWCNTs modified GC (GC/Nf‐MWCNTs/Fe(bpy)32+) manifests stable redox peaks, characteristics of Fe(bpy)32+. The GC/Nf‐MWCNTs/Fe(bpy)32+ exhibits effective electrochemical oxidation of nicotine, diminishing the overpotential relative to GC/Nf‐MWCNTs. The limit of detection is 0.1 μM (experimentally observed) with two different linear calibration ranges between 0.1 to 600 μM and 600 to 3000 μM. Electrocatalytic responses observed at GC/Nf‐MWCNTs/Fe(bpy)32+ indicate superior performance for nicotine determination with acceptable selectivity, stability, and reproducibility. Additionally, the nicotine present in real samples such as beedi and tobacco are also analyzed with satisfactory recovery percentages. [ABSTRACT FROM AUTHOR]

In the present study, paclitaxel (PTX), multi‐walled carbon nanotubes (MWCNTs), and doxorubicin (DOX) have been simultaneously doped into the poly(ϵ‐caprolactone) (PCL)/chitosan/zein core‐shell nanofibers to increase its cytotoxicity for MCF‐7 breast cancers killing. The physico‐chemical properties of synthesized nanofibers were determined by scanning electron microscope, Fourier‐transform infrared spectroscopy, tensile strength, and degradation rate determinations. The in vitro release studies demonstrated the sustained release of drugs from core‐shell nanofibrous scaffold. The cytotoxicity and compatibility of core‐shell nanofibers were investigated by their treating with MCF‐7 breast cancer cells and L929 normal cells, respectively. PCL/PTX/chitosan/zein/MWCNTs/DOX core‐shell nanofibers containing 1 wt% MWCNTs, 100 μg ml−1 DOX and 100 μg ml−1 PTX had a high biocompatibility with a 84% MCF‐7 cancer cells killing. The in vivo studies revealed the synergic effects of MWCNTs and anticancer drugs on the tumor inhibition. This method could be considered as a new way for developing of MWCNTs loaded‐nanofibers for cancer treatment in future. [ABSTRACT FROM AUTHOR]

In this article, alteration in the mechanical performance of glass fiber/epoxy (GE) composite due to individual and simultaneous incorporation of multi‐walled carbon nanotubes (CNT) and multi‐layered graphene sheets (MLG) in both their pristine and oxidized forms are discussed. Further, the effect of two different nanofiller concentrations (0.1 and 0.3 wt%) were also studied to optimize the performance. Flexural testing of these composites was performed at room temperature (RT), 70 and 110°C in‐situ temperatures to understand their temperature dependence behavior. From all considered composites, GE composite with 0.1 wt% of oxidized CNT and MLG mixture (O‐(CNT‐MLG)) (1:1) showed best flexural performance at all the in‐situ temperatures. The presence of oxidized CNTs and MLGs in the GE composite provided a synergetic strengthening effect like CNT pull‐outs and crack bridging confirmed through SEM imaging. Besides, oxidation helped in the dispersion of CNT and MLG in the composite. Glass transition temperature (Tg) of all the considered composites was evaluated using Differential Scanning Calorimetry (DSC). Fourier Transformed Infra‐red Spectroscopy (FTIR) was also conducted to confirm the functionalization of CNT and MLG after oxidation. During the fractography study, these composites showed variation in fiber/matrix interfacial bonding, matrix deformation, dispersion of nanofillers and fiber imprints, which helped to understand different failure modes responsible for the gross failure of the composites. [ABSTRACT FROM AUTHOR]

The development of tunable UV‐curable polymeric composites for functional applications, taking into consideration environmental issues and additive manufacturing technologies, is a research topic with relevant challenges yet to be solved. Herein, acrylic composites filled with 0–3 wt.%. polyaniline/ multiwalled carbon nanotubes (PANI/MWCNT) are prepared by Digital Light Processing (DLP) in order to tailor morphology, thermal, mechanical, and electromechanical properties. Viscosity, real‐time infrared spectroscopy, and cure depth tests allow optimizing resin composition for suitable DLP printing. 2 wt.% is the maximum filler content reproducibly embedded in the polymer matrix. The advantages of PANI/MWCNT (50/50 wt.%) compared with single‐component composites include safety issues, enhanced printability, increased electrical conductivity and thermal stability, and lower electrical percolation threshold (0.83 wt.%). Above this threshold the composites display excellent piezoresistive response, no hysteresis, and stability for over 400 compression cycles. The pressure sensibility (PS) of 2 wt.% composites decreases with applied pressure from PS ≈ 15 to 0.8 Mpa−1 for maximum pressures of 0.02 and 0.57 MPa, respectively. A proof‐of‐concept of the functionality of the novel materials is developed in the form of a tactile sensor, demonstrating their potential for pressure sensing applications as cost‐effective, sustainable, and flexible materials for printed electronics. [ABSTRACT FROM AUTHOR]

The present work reports a sensitive and simple sensor based on an electrochemically treated pencil graphite electrode (pre‐PGE) modified with multi‐walled carbon nanotubes (MWCNTs) for electrochemical determination of L‐tryptophan (L‐Try) detection in the presence of uric acid. Electrochemical and physical characterizations of the MWCNTs/pre‐PGE were investigated using cyclic voltammetry (CV), Electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM) techniques. Under the optimized conditions, the linear working range was 0.030–200.0 μM with a limit of detection of 9.0 nM using the differential pulse adsorptive stripping voltammetry (DPAdSV) method. The proposed sensor exhibited good sensitivity, repeatability, reproducibility, and stability. The MWCNTs/pre‐PGE were successfully applied to L‐Try determination in commercial poly‐amino acid supplements with good recovery and accuracy. [ABSTRACT FROM AUTHOR]

As a nanometer material, carbon nanotubes can inhibit the expansion of microcracks and is of great significance to improve the mechanical properties and durability of concrete. In order to explore the mechanism of dynamic mechanical properties enhancement of carbon nanotube reinforced concrete under impact load after freeze–thaw cycles, the dynamic compression test of carbon nanotube reinforced concrete samples was carried out by using the control variable method with freeze–thaw cycles and impact air pressure as variables. The results showed that under the same impact pressure, the peak stress of carbon nanotube reinforced concrete sample decreased gradually with the increase of freeze–thaw cycles. The corresponding strain increased slightly, and the stress–strain curve moved to the right and down as a whole. Under the same freeze–thaw cycle, the peak stress of carbon nanotube reinforced concrete sample increased with the increase of strain rate, and the dynamic strength growth factor DIF also increased, showing an obvious strain rate strengthening effect. In addition, under the same freeze–thaw cycles and external impact load, the dynamic strength of carbon nanotube concrete is 41.97 and 54.21 MPa, respectively, which is 22.27 and 25.81% higher than that of ordinary plain concrete. The results show that carbon nanotube reinforced concrete samples have higher dynamic mechanical properties and freeze–thaw cycle resistance than ordinary plain concrete samples. [ABSTRACT FROM AUTHOR]

Phthalic Acid Esters (PAEs) are a well‐known ubiquitous environmental pollutant that holds a significant threat to human health. Despite their harmful effects, the constant use of PAEs in producing flexible plastic products has awakened society's great concern, especially with their ability to leach, migrate, or evaporate from plastics to the surrounding. Therefore, rapid and easy monitoring of the PAEs presence in different environments is crucial. This study introduces a rapid PAE detection technique that shows potential for overcoming the limitations of already existing PAE detecting methods. This novel PAE sensing platform (buckypaper) is developed using highly conducting Multi‐Walled Carbon Nanotubes (MWCNT). The buckypaper adsorbs PAEs in solutions and decreases its conductivity. This conductivity decrement is detected using the Nyquist and Bode plots obtain from three‐electrode Electrochemical Impedance Spectroscopy (EIS) analysis. This novel method has shown that it has the potential to distinguish DEHP (di‐(2‐ethylhexyl) phthalate), DPHP (di‐(2‐propylheptyl) phthalate), and DnOP (di‐octyl phthalate) from other aromatic molecules such as toluene, xylene, naphthalene, and bisphenol‐A. Moreover, the developed buckypaper is sensitive down to 1000 (v/v) ppm concentrated PAEs in methanol solutions at room temperature, which exhibits the potential of using this platform as an in‐situ and real‐time PAE detecting sensor. [ABSTRACT FROM AUTHOR]

Suffering from sluggish charge transfer kinetics, carbon‐based perovskite solar cells (C‐PSCs) lag far behind the Ag/Au‐based normal PSCs in power conversion efficiency (PCE). Herein, the use of defective multi‐walled CNT (D‐MWCNT) is demonstrated to tune the charge transfer kinetics regarding hole transport layer (HTL) and the interface between HTL and carbon electrode. Benefiting from the electrostatic dipole moment interaction between the terminal oxygen‐containing groups of D‐MWCNT and 2,2′,7,7′‐tetrakis(N,N‐di‐p‐methoxyphenylamine)‐9,9′‐spirobifluorene, an interface coupling at molecular level is established and in turn, allows rapid charge transfer by edge effect induced electron redistribution and 1D hyper‐channels. Meanwhile, a seamless connection between HTL and carbon electrode is achieved in a novel modular C‐PSCs due to D‐MWCNT induced interface coupling with graphene at nanometer scale. Based on this strategy, high PCEs up to 22.07% (with a certified record PCE of 21.9% to date for C‐PSCs) and excellent operational stability have been achieved. [ABSTRACT FROM AUTHOR]

Lightweight and low‐cost flexible thermoelectric (TE) materials improve the heat‐to‐electricity conversion efficiency compared to rigid materials by minimizing the heat loss between TE devices and heat sources in waste heat recovery. Multi‐walled carbon nanotube (MWCNT) has excellent mechanical and electrical properties. However, the TE power factor (PF) of MWCNTs is much lower than single/double‐walled carbon nanotube (S/DWCNT), which is often lower than 40 µW m−1‐K−2. Herein an effective way to achieve high PFs of ≈1800 µW m−1‐K−2 for p‐type and ≈1000 µW m−1‐K−2 for n‐type in flexible MWCNT films is reported. The high power factor is achieved by taking advantage of the anisotropic electrical conductivity and isotropic Seebeck coefficient feature of 1D CNTs as well as the following doping and cold‐pressing to improve the electrical conductivity of MWCNT films. The PF values are comparable to that of state‐of‐the‐art S/DWCNT films and most inorganic TE materials. A Lego‐like TE generator (TEG) with an assembling structure is fabricated to show the heat‐to‐electricity ability of the materials, which exhibits the highest areal output power of ≈27 W m−2 among CNT‐based flexible TEGs. This method may be extended to other 1D‐material based composites to boost the development of high PF flexible TE materials. [ABSTRACT FROM AUTHOR]

Multi‐walled carbon nanotubes (MWCNT) were first non‐covalently functioned by tannic acid (TA), then blended with nitrile rubber (NBR) and ethylene propylene diene monomer (EPDM) with NBR:EPDM:TA‐MWCNT = 70:30:5. TA‐MWCNT and the composites had been characterized by various techniques, including Fourier transform infrared spectroscopy (FT‐IR), Raman analysis, transmission electron microscopy (TEM), mechanical properties testing, thermal‐oxidative aging testing, differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), and scanning electron microscopy (SEM). Results indicated that TA molecules were successfully absorbed to the surface of MWCNT. And compared with NBR/EPDM/MWCNT composites, the compatibility between NBR and EPDM had been significantly improved. The NBR/EPDM/TA‐MWCNT exhibited excellent mechanical properties and thermal‐oxidative aging properties due to the phenolic hydroxyl groups on the surface of TA‐MWCNT, which had high chemical reactivity and physical adhesion. These phenolic hydroxyl groups gave TA‐MWCNT better dispersion in the rubber matrixes and can participate in the vulcanization process, creating the firm interface between the rubber matrixes and the surface of MWCNT. [ABSTRACT FROM AUTHOR]

In this work, multi‐walled carbon nanotubes (MWCNTs) was modified with nitric acid and applied as efficient adsorbents for the removal of methylene blue (MB) in aqueous solution. The morphologies of the modified MWCNTs were characterized by N2 adsorption‐desorption (BET), transmission electron microscope (TEM) and X‐ray photoelectron spectroscopy (XPS). Batch experiments were conducted systematically to explore the effects of various parameters including mass dosage of adsorbents, initial concentration of MB dye, pH of solution and ionic strength about the adsorption performance with modified MWCNTs. The adsorption for MB pollutants achieves the highest efficiency of 95.18 % occurring at about pH 11 when the adsorbent dosage is at 1.0 g L−1, the initial dye concentration is at 50 mg L−1 and the concentration of NaCl is 0 M. And the Langmuir, Freundlich and Temkin equilibrium isotherms were researched. The results revealed both the Freundlich and Langmuir isotherms fitted well to experimental data suggesting adsorption of MB onto MWCNTs as a result of a monolayer formation. In addition, the adsorption behavior of MB dye followed the pseudo second‐order kinetics indicating there was a synergistic effect in the adsorption process based on the factors of mass transfer resistance in the particles, the external liquid membrane diffusion, surface adsorption and internal diffusion of the particles. [ABSTRACT FROM AUTHOR]

This paper investigates combined heat transfer improvement methods. These methods include introducing pulsating flow, adding nanofluids, and manipulating the flow's characteristics in a corrugated plate heat exchanger. Tests are carried out with multi‐walled carbon nanotube (MWCNT), graphene nanoplate (GNP), and a mixture of GNP and MWCNT meeting the requirement of 0.01% nanofluids volume fraction and exposed to pulsation. Results demonstrated that the use of pulsating frequencies from 0 to 30 Hz of GNP‐water, MIX nanofluids–water, and MWCNT–water nanofluids with a constant concentration of 0.01 wt% leads to a significant improvement in heat transfer. Using pure water at frequency f = 0 Hz as a benchmark, the Nusselt number of the mixture nanofluid increases by 15.2%, 27.5%, 40.4%, and 52.8% with the increase of frequency pulsation from 0 to 30 Hz with a slight effect on the pressure‐drop at this low used constant nanofluid concentration = 0.01%. The highest Nusselt number value for GNP‐water nanofluid improved by an amount of 58.3% at the highest frequency compared with pure water at f = 0 Hz. [ABSTRACT FROM AUTHOR]

BACKGROUND Potentiometric detections based on ion‐selective electrodes offer the advantages of simplicity, speed, and low cost over other electrochemical methods. In this work, the preparation of a novel carbon‐paste electrochemical sensor containing the synthesized N‐(1‐(4‐bromophenyl)‐3‐oxo‐3‐phenylpropyl)acetamide is described. Multi‐walled carbon nanotubes (MWCNTs) were incorporated into the electrode composition to promote electron transfer reactions. The modified carbon paste electrode was evaluated as a selective sensor for the detection of chromium (III). RESULTS: The prepared sensor showed nearly stable potentials in the pH range of 4.0–6.5, with a fast response time (<15 s). At the optimum conditions, the potentiometric method exhibited a linear response toward Cr(III) concentration in the range of 5.0 × 10−7 to 1.0 × 10−3 mol L−1 with a Nernstian slope of 19.5 ± 0.1 mV per decade and a detection limit of 3.1 × 10−7 mol L−1. CONCLUSION: The proposed sensor possesses the advantages of good selectivity to Cr(III) and an improved detection limit compared to the results of some other studies. Better selectivity can be attributed to the ability of the ionophore to form a stable chelate with Cr(III) ions. The new Cr(III) sensor showed excellent stability over 8 weeks and its response time was comparable to other previously reported chromium ion‐selective electrodes (ISEs). The simple, fast, and cheap synthesis method of ionophore provided other advantages for this study. The modified electrode was also used as a sensor for the end‐point detection in the potentiometric titration of Cr(III) against ethylenediaminetetra acetic acid (EDTA). © 2021 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

The design and exploration of efficient, stable and environmentally compatible organic emitters for an electrochemiluminescence (ECL) sensor is a promising topic. Herein, a novel environmentally-friendly luminophore, ZnBCBTP@MWCNTs, were fabricated via selfassembly of porphyrin molecules (ZnBCBTP) onto multiwalled carbon nanotubes (MWCNTs). The resulting luminophore ZnBCBTP@MWCNTs displayed not only the highly ECL property and but also the good accelerated electron mobility. Then, a label-free ECL biosensor based ZnBCBTP@MWCNTs was constructed for the ultrasensitive detection of uric acid. Excitingly, this proposed ECL biosensor performed a good linear relationship in the range of 0-300 µM with a low detection limit of 1.4 µM, thus offering another reliable and feasible sensing platform for clinical bioanalysis with good selectivity, stability, and repeatability. [ABSTRACT FROM AUTHOR]

In this study, a novel electrochemical sensor was developed for the detection of baicalein based on multi‐walled carbon nanotube (MWCNT) and banana peel derived biomass carbon (BPBC) composite modified glassy carbon electrode (GCE). The BPBC was synthesized by carbonization and alkali activation method using commonly available banana peel as the raw material, which was further mixed with MWCNT to obtain BPBC‐MWCNT composite. Then the composite modified GCE was fabricated and used for voltammetric detection of baicalein with a wide detection range from 0.0040 to 100.0 μM as well as a low detection limit of 1.33 nM (3σ/S). Also, the electrochemical behaviors of baicalein on BPBC‐MWCNT/GCE were investigated by cyclic voltammetry in detail. The proposed method was applied to the detection of baicalein content in Shuanghuanglian oral liquid with satisfactory results. Therefore, this work extended the electrochemical method for the drug analysis by using biomass‐derived carbon‐based composite. [ABSTRACT FROM AUTHOR]

In this article, we introduced a novel electrochemical biosensor for the detection of microRNA‐126. The biosensor utilizes a hybridization assay combined with multi‐walled carbon nanotubes and gold nanorod‐decorated screen‐printed carbon electrodes. For electrode preparation, gold nanorods were first immobilized onto the surface of bare and multi‐walled carbon nanotube‐modified screen‐printed carbon electrodes, and the thiol tagged‐capture probe was immobilized on the electrode surface through gold and thiol group interaction. After the immobilization, thiol tagged‐capture probe hybridized with the target sequence. Under optimum conditions, we determined limit of detection (LOD) and limit of quantification (LOQ) as high as 11 nM and 36 nM, respectively. [ABSTRACT FROM AUTHOR]

We report a hybrid material obtained by dispersing the polyoxometalate n‐[Bu4‐N]2[Mo6O18NC13H9] functionalized with 2‐aminofluorene (POMAF) and multi‐walled carbon nanotubes (MWCNTs) in 1,3‐dioxolane (MWCNT‐ POMAF). We demonstrate the peroxidase‐like activity of the hybrid material and its application for the amperometric quantification of hydrogen peroxide at −0.450 V previous drop‐coating at glassy carbon electrodes, with a linear range between 1.0 μM and 6.0 μM and a detection limit of 330 nM. The reproducibility was 2.2 % using one MWCNTs‐POMAF dispersion, and 3.9 % using 4 different dispersions. The sensor was successfully used for the quantification of hydrogen peroxide in enriched milk samples. [ABSTRACT FROM AUTHOR]

In this work, new ways to reinforce the performance of starch by incorporating nano‐diamond (ND) and chitosan‐grafted MWNTs (MWNTs‐CS) are developed. The composites are characterized by tensile properties, dispersion properties, thermal analysis, fourier transform infrared (FT‐IR), X‐ray diffractions (XRD) studies, and water vapor permeability (WVP) tests. Loading of ND not only improves the solubility, but also increases the tensile strength, elongation at break and Young's modulus of the starch composite films, which increases by 235.82%, 78.98%, and 976.51%, respectively. In particular, the synergy effects of Young's modulus achieves the effect of "1 + 1 > 2" which may be attributed to the fact that ND can be adsorbed on the surface of MWNTs by π‐π interactions, which prevents aggregation of MWNTs. Meanwhile, hydrogen bonds between grafted CS and the starch matrix are responsible for generating effective load transfer between ND/MWNTs‐CS and the starch matrix, resulting in the simultaneously increased strength and toughness of the nanocomposites. Furthermore, composite film containing ND and MWNTs‐CS shows the lowest water vapor permeability among the composite films prepared in this study. [ABSTRACT FROM AUTHOR]

The combination of nanostructured transition metal oxides and carbon materials is a promising approach to obtain inexpensive, highly efficient, and stable bifunctional electrocatalysts for the oxygen reduction (ORR) and the oxygen evolution (OER) reactions. We present a strategy for improving the bifunctional ORR/OER activity of supported FeCoOx nanoparticles by tuning the properties of multi‐walled carbon nanotubes (MWCNT) via nitrogen doping during their synthesis in the presence of ammonia and subsequent oxidative functionalization. In‐depth structural characterization indicates that oxidative treatment provides fine control of the dispersion and localization of FeCoOx nanoparticles in MWCNT, while the optimal degree of nitrogen doping leads to increased bifunctional activity due to enhanced electrical conductivity as well as improved catalyst stability, in both OER and ORR conditions, for nanoparticles formed by two different synthesis routes. The findings reported can be strategically considered for the design of high‐performance reversible ORR/OER electrocatalysts. [ABSTRACT FROM AUTHOR]

Wearable flexible electronic strain sensor devices have developed rapidly in recent years due to their potential capacity to detect human motion in various situations. However, it still remains still a big challenge to fabricate strain sensors with high sensitivity over a wide workable strain range. In order to meet this challenge, a new type of strain sensor based on elastomer/carbon nanotube composite fiber is reported in this work. Elastomer fibers are initially prepared via the electrospinning of styrene ethylene butene styrene block copolymer (SEBS). The resultant SEBS fibers are then functionalized by sequentially coating with dopamine (DA) coating and carboxyl group (‐COOH) grafted multi‐walled carbon nanotubes (MWCNTs) under vacuum filtration and ultrasonication. Scanning electron microscopy (SEM) and thermogravimetric analysis reveals that a large amount of MWCNTs is firmly bonded onto the SEBS fibers and evenly distributed. SEBS@PDA/MWCNTs composite fibers based strain sensors exhibit excellent performance, including a high gauge factor of 3717 and large workable strain range up to 530%. Furthermore, the developed sensors demonstrate excellent washing fastness and superior sensitivity in monitoring both small strains (e.g., pulse beats and vocal cord vibrations) and large strains (e.g., finger, elbow, and knee bending). [ABSTRACT FROM AUTHOR]

Nowadays, the main obstacle for further miniaturization and integration of nucleic acids point‐of‐care testing devices is the lack of low‐cost and high‐performance heating materials for supporting reliable nucleic acids amplification. Herein, reduced graphene oxide hybridized multi‐walled carbon nanotubes nano‐circuit integrated into an ingenious paper‐based heater is developed, which is integrated into a paper‐based analytical device (named HiPAD). The coronavirus disease 2019 (COVID‐19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) is still raging across the world. As a proof of concept, the HiPAD is utilized to visually detect the SARS‐CoV‐2 N gene using colored loop‐mediated isothermal amplification reaction. This HiPAD costing a few dollars has comparable detection performance to traditional nucleic acids amplifier costing thousands of dollars. The detection range is from 25 to 2.5 × 1010 copies mL−1 in 45 min. The detection limit of 25 copies mL−1 is 40 times more sensitive than 1000 copies mL−1 in conventional real‐time PCR instruments. The disposable paper‐based chip could also avoid potential secondary transmission of COVID‐19 by convenient incineration to guarantee biosafety. The HiPAD or easily expanded M‐HiPAD (for multiplex detection) has great potential for pathogen diagnostics in resource‐limited settings. [ABSTRACT FROM AUTHOR]

While the efficiency of synthetic surfactants in controlling the dispersion behaviour of nanomaterials in aqueous solution has been well documented, issues on environmental impact remain unsolved. The aim of this study is to synthesize multi‐walled carbon nanotubes (MWCNTs) inks using green surfactants and their chemical, physical, and electrical performances are compared to those of synthetic surfactant inks. The conductive ink is synthesized by dispersing MWCNTs in surfactant solution (gum Arabic [GA], alkali lignin [AL], polyvinylpyrrolidone [PVP] or pluronic F‐127 [PL]) with various concentrations. Among four investigated surfactants, GA/MWCNTs and PVP/MWCNTs inks are selected for further investigation due to their excellent dispersion stability. The printability of both inks is assessed by analyzing the quality of the conductive patterns printed with different inkjet printers theoretically and experimentally. It is found that multi‐nozzle printer is capable of developing printed patterns with lower sheet resistance compared to single‐nozzle printer. Overall, 5 GA/MWCNTs ink recorded as the most stable ink with only 14.4% reduction of absorbance after 30 days and with zeta potential value of −40.3 ± 5.36 mV. Ten layers of 5 GA/MWCNTs ink printed on PVA demonstrate a dense MWCNTs networks, which contribute to the lowest surface resistance of 3.0 kΩ sq−1. [ABSTRACT FROM AUTHOR]

A highly sensitive, simple and low cost sensor for the quantification of the diclofenac has been constructed. This sensor consists of a carbon paste nano‐structured by Multi‐Walled Carbon Nanotubes (G‐MWCNT)‐CPE. Scanning electron microscopy (SEM) and voltammetry technique were used to characterize the electrode material and to determine the analytical performances of the sensor in comparison with those obtained at a G‐CPE. The electrochemical oxidation of diclofenac on both G‐CPE and (G‐MWCNT)‐CPE electrodes is mainly controlled by adsorption, presenting a maximum peak current intensity in H2SO4 0.5 mol L−1. The carbon nanotubes, as well as they provide higher conductivity of the paste, act as spacers between the flake graphite particles and avoid their stacking in order to make the surface of graphite particles more accessible to DCF adsorption. The voltammetric measurements of diclofenac on (G‐MWCNT)‐CPE provide a large quantification range from 0.02 to 1 μmol L−1, a detection limit of 0.004 μmol L−1 and quantification limit of 0.014 μmol L−1 under the optimized operating conditions (H2SO4, 0.25 M+KCl 0.25 M, scan rate of 30 mV s−1, preconcentration time 18 min. and MWNTC% (30 %)). The (G‐MWCNT)‐CPE sensor was successfully applied to natural water samples, just acidified with sulfuric acid (pH<1). These samples were doped with diclofenac in sub‐micromolar range and the developed method was validated with excellent recoveries (within a maximum of 3 % difference from 100 %) for all samples indicating no interference effects of the water matrix. [ABSTRACT FROM AUTHOR]

Graphene oxide (GO)/multi‐walled carbon nanotubes (MWCNTs) modified nanofiltration (NF) membranes were successfully fabricated by interfacial polymerization of piperazine (PIP) and 1,3,5‐benzenetricarbonyl trichloride (TMC). Compared with the pristine polyamide (PA) membrane and GO membrane, the typical structure of the granular protrusions on the surface of the GO/MWCNTs membrane gradually disappeared, and a regular ordered morphology appeared. The membrane thickness and surface roughness were increased according to the results of field emission scanning electron microscopy (FE‐SEM) and atomic force microscopy (AFM). The contact angle of GO/MWCNTs NF membranes progressively decreased from 57° to 23°, indicating the enhancement of surface hydrophilicity. The best NF performance was achieved when the ratio of GO to MWCNTs was 6:3 (G‐M‐3). The water flux was 55.6 L/m2.h, which was 33.7% higher than that of the GO membrane, and the rejection rate for Na2SO4 was maintained at approximately 94%. Both modified NF membranes could treat actual dyeing‐printing wastewater effectively. The anti‐fouling performance of G‐M‐3 was better than that of G3. Therefore, GO/MWCNTs‐modified NF membranes have a good application prospects in the field of wastewater treatment and water purification. [ABSTRACT FROM AUTHOR]

Polyethyleneimine‐modified magnetic multi‐walled carbon nanotubes were developed to extract 10 mycotoxins. Simple modification of polyethyleneimine was achieved on the magnetic substrate by using an epoxy‐containing silane agent as a linker. The resultant magnetic adsorbent was integrated with reverse phase and anion exchange interaction sites. Under optimal extraction conditions, only 20.0 mg adsorbent was used to extract the mycotoxins from 50.0 mL loading solution. The maximum adsorption capacities of the adsorbent toward the mycotoxins ranged from 4.9 to 10.2 mg/g. Adsorption and desorption were completed within 3.0 and 2.0 min, respectively. The adsorbent could be used for six repeated runs without evident change in extraction performance. The adsorbent combined with liquid chromatography–tandem mass spectrometry was applied further to analyze the mycotoxins in milk. The absolute recoveries of the 10 mycotoxins ranged from 88.3 to 103.5% with relative standard deviations that ranged from 2.4 to 6.5%, and their limits of detection were 0.003 to 0.442 μg/kg. The proposed adsorbent has great potential in the routine analysis of mycotoxins in ordinary analytical chemistry laboratory. [ABSTRACT FROM AUTHOR]

In this work, the removal of a model antibiotic named 'doxycycline' by three‐layered double hydroxides (LDHs) such as Mg–Fe LDH, Mg–Al LDH and Mg–Al/MWCNT LDH was investigated. Almost full characterisation of the prepared LDHs before and after adsorption was conducted using X‐ray diffraction, Fourier‐transform infrared spectroscopy, zeta potential, Brunauer–Emmett–Teller used for detecting the surface area, high‐resolution transmission electron microscope (HRTEM) and field emission scanning electron microscope. The effect of different factors on doxycycline adsorption capacity was investigated. The removal percentages of doxycycline were 80, 82 and 92% by Mg–Fe LDH, Mg–Al LDH and Mg–Al/MWCNT LDH, respectively. These results were attributed to the difference in the pore volume and geometry between the different LDHs. The isothermal and kinetic models of adsorption were also studied. The kinetics of adsorption were described by the second‐order equation with a better fit showed by a high R2 value. Mathematically, the Langmuir and Freundlich models best fitted the equilibrium data. [ABSTRACT FROM AUTHOR]