Search Results (1,544)

The integration of enzyme-loaded polymeric matrices with carbon-based nanomaterials and metallic nanoparticles into wearable multisensing patches, coupled with miniaturized portable detection devices, enables real-time, highly sensitive, and simultaneous monitoring of key clinical biomarkers (e.g., glucose, lactate, and H₂O₂) in clinical and point-of-care applications. Multiplex biosensors were fabricated by modifying screen-printed carbon paste electrodes (SPEs) with different composite nanomaterials based on carbon nanomaterials such as multi-walled carbon nanotubes (MWCNTs), single-walled carbon nanotubes (SWCNTs), or fullerenol (FL), the redox mediator Prussian Blue, and platinum nanoparticles (PtNPs). Chitosan and sol–gel polymer matrices were used to immobilize the enzymes glucose oxidase (GOx) and lactate oxidase (LOx), thus ensuring not only increased sensitivity and operational stability, but also high specificity for biomarker detection (glucose and lactate). Among the nanomaterials used for the development of multiplex biosensors, the SWCNT-PtNP composite was highlighted by electrochemical studies as having a significantly superior electrocatalytic activity toward the reduction of H₂O₂. This reaction occurs at a low applied potential of only −0.2 V vs. Ag/AgCl, achieving a specific sensitivity of 224.6 mA·M⁻¹·cm⁻², over a concentration range of 0.07 to 28.26 mM, and a detection limit of 3.2 μM. When functionalized with enzymes, SWCNT-PtNP-based biosensors exhibit improved conductivity, allowing the detection of glucose and lactate at a potential of −0.05 V vs. Ag/AgCl. The specific sensitivities obtained are 20.25 mA·M⁻¹·cm⁻² for glucose and 94.76 mA·M⁻¹·cm⁻² for lactate, and the corresponding detection limits are 23.6 μM and 5.0 μM, respectively. Finally, a wearable patch integrating the multiplex (bio)sensor with a portable potentiostat enabled simultaneous, sensitive, and selective detection of glucose, lactate, and H₂O₂ in sweat samples. Full article

Porous multi-walled carbon nanotube (MWCNT) films combine strong optical absorption with thermal, Kerr-like, thermo-optical, and magneto-optical responses. However, these effects depend on film structure and may require different design conditions. In this work, a multiphysics model was used to analyze 12 MWCNT film configurations with dependance on thicknesses, porosity, and orientation parameters. The model included optical attenuation, transient heating, nonlinear refraction, thermo-optic modulation, magneto-optical response, and optical phase shift under irradiances of 7–20 MW cm⁻² and magnetic fields up to 1 T. Optical density ranged from approximately 0.4 to 2.8, while transmittance showed negligible variation with irradiance. Thin and porous films produced the highest temperature rises, approximately 4.5 K, and the largest total refractive-index changes. In contrast, thicker films generated larger accumulated phase shifts. The thermo-optic contribution is dominated under nanosecond laser irradiation. As the pulse duration approached the picosecond regime, the lower deposited energy reduced the photothermal response, so the Kerr-like and magneto-optical terms accounted for a larger total refractive-index change. This predictive parametric study identifies architecture- and pulse-dependent trends for future experimental evaluation of multifunctional MWCNT films. Full article

This study investigates the crystallization behavior of poly(butylene succinate) (PBS) through blending with highly crystalline polyoxymethylene (POM) to address the inherently slow crystallization rate of PBS. The non-isothermal crystallization kinetics of the individual constituents within the blend systems were systematically investigated to elucidate their crystallization behavior under cooling conditions. In addition, the influence of multi-walled carbon nanotube (MWCNT) incorporation on the mechanical, thermomechanical, and morphological properties of PBS/POM blends was evaluated. The crystallization behavior was analyzed using kinetic approaches under non-isothermal conditions. Spherulite morphology was observed via polarized optical microscopy equipped with a controlled heating–cooling stage to elucidate spherulitic development. Scanning electron microscopy (SEM) revealed no obvious micron-scale phase separation in the PBS/POM blends, while the distinct crystallization behavior of the PBS and POM phases observed by differential scanning calorimetry (DSC) indicated that the two components retained their individual crystalline phases, supporting the partial miscibility of the blends. In the ternary systems, SEM observations showed a relatively uniform distribution of MWCNTs at the spatial scale accessible by SEM, with no pronounced micron-scale agglomerates readily discernible within the examined regions. Mechanical analyses demonstrated that the incorporation of MWCNTs enhanced the properties of the blends, particularly the elastic modulus and tensile strength. Kinetic analysis further indicated that MWCNTs influenced the crystallization behavior of the PBS and POM phases through nucleation effects, with their influence depending on the PBS/POM blend composition. Full article

Environmentally released carbon nanomaterials can alter polycyclic aromatic hydrocarbon (PAH) attenuation in agricultural soils, yet how their properties influence biodegradation in association with contaminant bioavailability and indigenous microbial responses remains unclear. This study compared nano-biochar (NBC), pristine and hydroxylated multi-walled carbon nanotubes (MWCNTs; 4–6 nm and >50 nm) in phenanthrene-contaminated soil, using raw biochar (RBC) as parent reference material. NBC showed the strongest promotion, reaching 68.17% biodegradation at 60 d and a maximum rate of 3.00 mg/kg/d, compared with 58.31% and 2.00 mg/kg/d in the unamended phenanthrene-spiked control. RBC exerted a weaker positive effect, suggesting biochar nanosizing favored biodegradation, accompanied by moderate bioavailability reduction and stimulation of microbial abundance, enzyme activity and diversity. In contrast, MWCNTs inhibited biodegradation, with reduced β-HPCD-extractable phenanthrene, suppressed polyphenol oxidase activity and more pronounced community shifts, while higher abundance of PAH-degradation gene nidA did not correspond to enhanced biodegradation. Pristine MWCNTs showed the lowest initial β-HPCD-extractable phenanthrene and biodegradation rates, whereas small-diameter MWCNTs most strongly limited final biodegradation extent, consistent with greater surface reactivity and intensified cell-contact stress. Hydroxylated MWCNTs exhibited weaker inhibition than pristine counterparts. These findings highlight the importance of material properties in shaping PAH fate and microbial ecology in agricultural soils. Full article

This study examined the combined effects on highly foamed cementitious materials of varying concentrations of multi-walled carbon nanotubes (MWCNTs), an air-entraining agent (AEA), and three superplasticizers (SPs): a lignosulfonate-based superplasticizer (SP-LS), a polyacrylate-based superplasticizer (SP-PA), and a polycarboxylate ether-based superplasticizer (SP-PCE). Setting time, semi-adiabatic exothermic-temperature (EXO) profile tests, zeta potential analysis, pH and electrical conductivity (EC) measurements, and foam stability were used to assess the suspensions and pastes. Adding up to 1.5% MWCNTs to an alkaline air-entraining agent (AEA) and SP-LS mostly shifts the zeta potential toward a negative value and stabilizes the suspension and foam. When MWCNTs and SP-LS were added to the foamed paste, the initial viscosity dropped by 12.1% to 7%, whereas with SP-PA and SP-PCE it dropped by 20–48% and 18–50%, respectively. Adding MWCNTs and SP-LS to the foamed paste mostly decreases the density. Using SP-LS is very helpful for interactions between AEA and MWCNTs, thereby stabilizing the air bubble walls. This study underscores the importance of pH and EC of the AEA and SP in affecting the cement paste’s hydration process. Full article

It is essential to design electrode structures which simultaneously ensure mechanical strength and facilitate rapid sodium-ion transport to enable practical and large-scale sodium-ion battery (SIB) applications. In this study, we report a novel anode material featuring a cross-linked architecture composed of MoS₂ reinforced internally by catalytically derived CoS₂@C-supported carbon nanotubes (CNTs), and externally by commercial multi-walled carbon nanotubes (MWCNTs). This dual-reinforced configuration effectively prevents MoS₂ layer aggregation, enhances structural integrity, and establishes continuous conductive frameworks for efficient electron transmission. Additionally, it offers ample ion-diffusion pathways and mechanical resilience to buffer volume changes during cycling. Density functional theory (DFT) simulations reveal that the modified MoS₂ structure exhibits a significantly reduced sodium-ion diffusion barrier, contributing to enhanced charge-discharge kinetics. The CoS₂@C/CNTs@MoS₂@MWCNTs electrode achieves remarkable cycling stability, retaining 395 mA h g⁻¹ at 1 A g⁻¹ for 2000 cycles. In situ X-ray diffraction (XRD) along with kinetic analyses confirm a pseudocapacitance-dominated storage mechanism. Furthermore, full coin-type cells assembled with Na₃V₂(PO₄)₃ cathodes demonstrate excellent cycling performance, demonstrating the practical potential of this design strategy for advanced SIBs. Full article

The multiwalled carbon nanotube, MWCNT-7, is carcinogenic to rat lungs when inhaled over the course of 2 years, but does not induce pleural mesothelioma. In contrast, intratracheal instillation of MWCNT-7 causes both lung tumors and pleural mesotheliomas. To explore the possibility of the use of the intratracheal instillation technique in risk characterization, we administered this widely used reference material using instillation to male F344 rats at doses of 0.0175, 0.07, 0.28, or 0.42 mg/kg once per week for 13 weeks, followed by an observation period of 91 weeks and compared the dose–response toxicological data with the 2-year inhalation study. Lung tumors and pleural mesotheliomas were induced in a dose-dependent manner (the 0.42 mg/kg group was excluded from analysis of lung tumor formation). The lung burden of MWCNT-7 at week 13 was dose-dependent: 0.0302, 0.191, 0.98, and 1.369 mg/lung in the 0.0175, 0.07, 0.28, and 0.42 mg/kg groups, respectively. The number of fibers in the pleural lavage fluid was also dose-dependent. The no-observed-adverse-effect-level (NOAEL) of MWCNT-7’s carcinogenicity was 0.0302 mg/lung based on no significant lung tumor induction and no mesothelioma induction in the 0.0175 mg/kg group. When compared based on lung burden, the dose–response relationship and NOAEL of lung tumor induction resembled those in the 2-year inhalation study, offering the possibility of the application of this protocol for risk characterization. Full article

Carbon nanotubes (CNTs) are widely used as nanoscale reinforcements in polymer composites because of their high stiffness, high aspect ratio, and ability to enhance interfacial stress transfer. In woven Kevlar/epoxy composites, however, the mechanical benefit of CNT addition depends not only on nanotube presence, but also on whether the fabric Fiber orientation enables the CNT-modified interface to participate effectively in the dominant load path. In this study, woven Kevlar/epoxy composites with and without 4 wt.% multi-walled carbon nanotube (MWCNT) treatment were investigated under three displacement rates, namely 1, 10, and 100 mm/s, for two specimen orientations relative to the woven yarn directions: 0°/90° and ±45°. The 0°/90° Fiber orientation represents a tension-dominant load path, whereas the ±45° Fiber orientation promotes yarn rotation and matrix-shear-dominant deformation. The experimental results show that CNT treatment produces a clear increase in elastic modulus in the 0°/90° composites, with an improvement of approximately 40–50% at the lowest loading rate and continued enhancement at higher rates. In contrast, only limited gains are observed in the ±45° composites. The calculated CNT engagement index reached 0.8667 in the 0°/90° Fiber orientation but remained low or negative in some ±45° loading conditions, indicating that the effectiveness of CNT reinforcement depends strongly on Fiber orientation relative to the woven yarn directions. To interpret this behavior in a design-oriented manner, three Fiber orientation-sensitive comparison parameters are introduced: the CNT engagement index, the Fiber orientation sensitivity factor, and the rate amplification factor. These descriptors distinguish absolute stiffness from actual reinforcement utilization and indicate that modulus improvements depend on specimen orientation relative to the woven yarn directions. This study indicates that fabric Fiber orientation governs whether the CNT-modified interface is effectively mobilized or largely bypassed. This provides a useful framework for selectively deploying CNT reinforcement in woven protective composite systems and for rethinking nanotube reinforcement as a load-path-dependent design feature rather than a universally effective additive. Full article

This work describes the design and characterization of nanocomposites based on multi-walled carbon nanotubes (MWCNTs) and commercial polymer matrices for innovative electronic applications. This work addresses the need for advanced materials for flexible electronics, sensing, and electromagnetic shielding. Sipolprene^® 25170-W, a flexible and durable polyester–polyether block copolymer, was used as the matrix. For filler incorporation, the commercial masterbatch Plasticyl™ PBT-1501 (15 wt% of MWCNTs in PBT, polybutylene terephthalate) was employed, ensuring operational safety and ease of dispersion. The samples were produced as films (with masterbatch contents ranging from 10% to 30% corresponding to a MWCNT content ranging from 1.5 wt% to 4.5 wt%) via twin-screw extrusion with a flat die. Characterization included SEM, FT-IR, TGA, DSC, tensile testing, surface wettability, volume resistivity measurements, and electro-mechanical tests. All the results confirmed good dispersion of the filler within the matrix: from a mechanical point of view, the addition of MWCNTs increased the Young’s modulus from 25 MPa of the neat material to 122 MPa of the material containing 4.5 wt% of MWCNTs, enhancing stiffness while maintaining good film handleability. Thermal analysis revealed the high stability of the obtained system and allowed us to identify the appropriate processing temperature parameters to guarantee the thermal stability of the materials during processing. Finally, electrical tests demonstrated a significant reduction in volume resistivity with increasing filler content: the volume resistivity decreased by about eleven orders of magnitude, from approximately 10⁸ Ohm × cm of the unmodified material to 10⁻³ Ohm × cm for the material containing 4.5 wt% of MWCNTs. the sample with 30% of filler exhibited the typical behavior of a conductive material, and it was demonstrated that it could be used as an in situ strain sensor. All these findings confirm the potential of the developed materials for advanced technological applications. Full article

Airborne viral transmission necessitates effective indoor air purification strategies. Conventional methods often face operational challenges, including potential secondary aerosolization and performance degradation under high-humidity conditions. This study evaluates a hybrid control system integrating a multi-walled carbon nanotube (MWCNT) field-emission plasma with a UV-LED/TiO₂ photocatalyst to continuously inactivate airborne bacteriophages. The system’s performance was assessed under varying applied voltages and relative humidity (RH) levels. The kinetic results demonstrated that the hybrid configuration yields a synergistic inactivation effect compared to the isolated plasma or photocatalytic treatments. Based on the kinetic enhancement, it is hypothesized that trace ozone generated by the plasma discharge serves as an electron acceptor on the UV-illuminated TiO₂ surface, thereby mitigating electron–hole recombination and enhancing the generation of hydroxyl radicals (·OH). Furthermore, the hybrid system exhibited operational resilience under high-moisture conditions, maintaining a robust active inactivation constant (k_a = 0.190 min⁻¹) at 70% RH without statistical degradation. This stability indicates that the continuous field emission effectively utilizes ambient moisture for secondary radical generation rather than being quenched by water condensation. Ultimately, this hybrid technology presents a continuous and adaptable engineering control measure for mitigating airborne pathogens in enclosed occupational environments, including those in high-humidity climates. Full article

The removal of phenol from contaminated effluents presents an industrial challenge owing to its toxicity at trace concentrations. Multi-walled carbon nanotubes (MWCNTs) have been studied as adsorbents for this purpose, given their high adsorption capacity and ease of separation. This work presents a theoretical phenomenological and numerical analysis of mass transport coupled to phenol adsorption on MWCNTs (external diameter $d_{ext}=50$ nm), parameterized using published experimental equilibrium data acquired under neutral pH conditions at 298 K. The mathematical model incorporates an effective pore diffusivity ($D_e=3.213\times {10}^{-10}$ m²/s) derived from pore structure parameters and describes three distinct scenarios: (1) pure physical adsorption via a modified Fick’s Second Law; (2) coupled diffusion–reaction with 0.5-order kinetics, herein treated as an empirical kinetic ansatz with phenomenological divergence from lumped empirical models (PFO/PSO); and (3) a parametric and sensitivity analysis on particle size (1–100 nm) and inlet concentration (1–5 mg/L). Numerical solutions confirm a Thiele modulus $\varphi \ll 1$ across the tested range, indicating a kinetically controlled regime with effectiveness factor $\eta \approx 1.0$, and validate the theoretical scaling $\varphi \propto C_s^{-0.25}$. During effluent polishing operations (reduction from 5 to 1 mg/L), the relative diffusive resistance increases by 49.5%, suggesting proportional increases in contact time or adsorbent dosage are required. A one-at-a-time (OAT) sensitivity analysis on $D_e$, $\kappa$, and $k_{obs}$ confirms that the kinetically controlled regime is preserved across plausible parameter ranges. The nanoscale architecture of MWCNTs reduces theoretical intraparticle diffusional resistance by several orders of magnitude relative to macroscopic granular adsorbents. We emphasize that these conclusions describe theoretical mass-transport advantages; experimental and pilot-scale validation under realistic, multi-component wastewater conditions remains an essential step before industrial deployment. Full article

Lithium-ion batteries are widely used in digital, power and energy storage fields due to their high capacity and high cycle life advantages. This paper systematically screens the formulation system and designs a high-efficiency production line that can effectively improve production efficiency, reduce production costs, and lower energy consumption per unit product. The produced nano-silicon-enhanced graphite anode material has excellent performance. The selection of silicon raw materials, types of solvents, types of dispersants, and grinding processes is studied to investigate the influence of these four factors on the wet grinding process for preparing nano-silicon. Finally, metal silicon obtained by air flow pulverization is selected as the raw material, isopropanol is used as the solvent, FA01 (carboxylic acid type) is used as the dispersant, and a two-stage wet grinding process is adopted to prepare the nano-silicon dispersion solution. Zirconia beads of 0.5 mm and 0.2 mm size are used as the grinding media for the first and second stages, respectively, with filling rates of 80% and 90%, respectively. The final prepared nano-silicon dispersion is stable in dispersion and has a narrow particle size distribution. The nano-silicon dispersion solution and the multi-walled carbon nanotube dispersion solution are mechanically ground and mixed using a sand mill. At the same time, the multi-walled carbon nanotubes are coated with the nano-silicon. Then, artificial graphite is added for compounding. Finally, through spray drying, the Si@MWCNTs@graphite (SMG) nano-silicon-enhanced graphite negative electrode material is prepared. The SMG nano-silicon-enhanced graphite negative electrode material with a silicon content of 2% has a first Coulomb efficiency of up to 84.32%. Full article

Multiwalled carbon nanotubes (MWCNTs) and nanoalumina (nano-Al₂O₃) have each been studied separately in asphalt binders, but whether their combined thermal gain translates into microwave-induced healing at the mixture scale remains unestablished. This study aimed to evaluate, through a multiscale approach, their combined incorporation into a polymeric asphalt binder modified with 4% styrene-butadiene-styrene (SBS), focusing on mechanical performance and microwave-induced healing. Binders with 0 to 6% hybrid nanomaterial (50:50) were characterized structurally, chemically, rheologically, and thermally, and mixtures were evaluated for rutting, four-point bending fatigue, and microwave heating and healing. A content of 2.3% was selected from rheological and thermal criteria. At this content, the mixture heating rate rose from 0.18 to 0.41 °C/s (127.8%) and rut depth decreased by 22.1%. The nanomodified binder reduced the top-to-bottom Jnr_3.2 gradient from over 250% to 56–59%, indicating improved storage compatibility rather than complete stability. Fatigue life at 250 μm/m decreased by 53.7%. Despite this, healing increased by 9.6% in dynamic modulus recovery and 61.9% in fatigue healing index. Overall, hybrid nanomodification improved resistance to permanent deformation and microwave-induced healing, clarifying their combined effect, although the fatigue penalty requires further investigation. Full article

In this work, composites based on thermosetting polymers (epoxy, polyester and vinylester resins) are presented, in which carbon particles and cenospheres are embedded. The influence of combinations of multi-walled carbon nanotubes (MWCNTs) and cenospheres, as well as amorphous carbon and cenospheres, on the mechanical properties and electromagnetic attenuation in (part of) the X-band range (812 GHz) of the developed composites has been studied. It has been established that the used combinations of carbon particles and cenospheres have the greatest positive effect on the mechanical properties of the composites based on vinylester resin. The developed materials demonstrate effectiveness for electromagnetic protection in the X-band range. The combination of a polymer matrix and appropriate fillers leads to significant attenuation of the radio frequency signal. The presented composites are suitable materials for integration into various defense systems—from coatings to structural elements with functional purposes. Full article

Environmental impacts of wastewater from textile and dyestuff industries are of growing concern due to limited freshwater availability and inadequate treatment facilities. Carbon nanotubes (CNTs) offer excellent adsorption potential because of their outstanding mechanical and chemical properties, however; their application in textile effluent treatment has not been widely studied. Moreover, laboratory-based studies are often costly and limited to a few variables, making it challenging to reveal the underlying relationships among several physicochemical parameters and CNT treatments. Multivariate statistical analysis (MVSA) offers an effective approach to overcome this challenge. To the best of our knowledge, no studies have integrated laboratory analysis of nanotube-based textile effluent treatment with an MVSA approach. This study aims to evaluate the physicochemical characterization of textile effluent, treat effluent with CNT, and explore the relationship between physicochemical parameters and CNT by integrating laboratory experiments with MVSA. For this purpose, single-walled CNT (SWCNT) and multi-walled CNT (MWCNT) were applied in batch mode adsorption experiments using various dosages and adsorption times. Scanning electron microscopy and Fourier transform infrared spectroscopy (FTIR), along with physicochemical analyses, were conducted to characterize the effluent and adsorption processes. The FTIR spectrum indicated that the absorption peaks of C=C, C=O, and the acidic f -OH group on CNTs enhance wettability and hydrophilic character, thereby increasing adsorption capacity. Experimental results demonstrated significant reductions in electrical conductivity (EC), total dissolved solids (TDS), turbidity, total organic carbon (TOC), and chemical oxygen demand (COD). CNT dosages of 1 to 5 g/100 mL and adsorption times of 2 to 5 h achieved removal efficiencies ranging from approximately 20% to 90% for SWCNT and MWCNT. MVSA indicated that MWCNT was more strongly associated with ionic and physical parameters (turbidity, TDS, EC, and pH), whereas SWCNT was more strongly related to organic load indicators, particularly COD and TOC. Overall, this study highlights the potential of CNT coupled with the MVSA technique as an effective and sustainable approach for textile wastewater treatment and offers valuable insights for researchers working in this field. Full article