Addition Of Multi-walled Carbon Nanotubes Research Articles

Improvement in the corrosion resistance of electrodeposited Ni-W alloy by MWCNT co-deposition and prevention of metal-carbon interfacial corrosion by carbide formation

Composite plating is an effective method which can enhance the properties of conventional metal plating by co-deposition of composite materials. In this study, multi-walled carbon nanotubes (MWCNTs) were used as a composite material to improve the corrosion resistance of Ni-W alloys, and the effect of the MWCNTs addition on the anti-corrosion properties was discussed. The corrosion current density of the Ni-W/MWCNTs composite decreased approximately 4 times from 16.6 to 4.6 μA·cm-2 in 3 wt% NaCl solution compared to the pristine Ni-W; this showed that the co-deposition of MWCNTs was effective for improvement in the corrosion resistance. However, the interfacial corrosion between the metal matrix and MWCNTs occurred in the high potential region and degraded the passivation properties of plating. This interfacial corrosion is caused by the high O content due to the hydroxyl groups on the acid-treated MWCNTs surface and the difference in W concentration between the interface of MWCNTs and the Ni-W matrix. Heat treatment in Ar atmosphere removes these hydroxyl groups and diffuses Ni and W into MWCNTs to form metal carbide (Ni6W6C), effectively alleviating interfacial corrosion. This study presents interfacial corrosion can be effectively mitigated by forming metal carbides at the interface of carbon materials in metal/carbon composites.

Corrigendum to “Effects of the addition of multi-walled carbon nanotubes on the microstructure and properties of Ti(C,N)-based cermets prepared by spark plasma sintering” [Materials Characterization 193 (2022) 112289

Corrigendum to “Effects of the addition of multi-walled carbon nanotubes on the microstructure and properties of Ti(C,N)-based cermets prepared by spark plasma sintering” [Materials Characterization 193 (2022) 112289

The influence of carbon nanotube addition on the shear-thickening performance of suspensions

The shear thickening fluid as a protective material has received increasing attention, and its impact resistance and its rheological properties are controllable by integrating various kinds of additives to a single phase shear thickening fluid. In this paper, the rheological properties of shear thickening fluids with 26 wt.% fume silica, PEG200 and different mass fraction of multi-walled carbon nano-tubes are investigated, and the effect of temperature from -5?C to 55?C on steady state rheological properties of 1.0 wt.% multi-walled carbon nanotubes reinforced shear thickening fluids is studied. Finally a single yarn pull-out test is conducted to examine the influence of multi-shear thickening fluid on the shear strength and inter-yarn friction of fabrics. The results show that the addition of multi-walled carbon nanotubes can improve significantly the viscosity and shear thickening efficiency.

Investigation of Thermal and Morphological Properties of PVC/PMMA Nanocomposite Added Carbon Nanotube at Various Ratios

Bu çalışmada çeşitli oranlarda karbon nanotüp katılmış PVC/PMMA nanokompozitinin termal ve morfolojik özelliklerinin incelenmesi amacıyla PMMA ve PVC gibi iki endüstriyel polimerin blendi ve çok duvarlı karbon nanotüp (MWCNT) katkısıyla bir polimerik nanokompozit hazırlanmıştır. Nanokompozitler, çözeltiden dökme tekniği ile hazırlanmıştır. Polimer blendine, toplam ağırlığın %1, %3 ve %5 oranlarında katılan çok duvarlı karbon nanotüplerin, nanokompozitin termal ve morfolojik özelliklerine etkisi incelenmiştir. Artan oranlı CNT katkısının TGA ve DSC üzerinde küçük değişiklikler yarattığı gözlendi. CNT oranı arttıkça camsı geçiş sıcaklığının (Tg) yükseldiği görüldü. SEM görüntülerinden, CNT ve polimer blendinin uyumlu bir etkileşim sergilediği görüldü.

Characterization of Functional Polyphenylsilsesquioxane (PhSiO<sub>3/2</sub>) Hybrid Glass Reinforced with MWCNTs

Hybrid (inorganic- organic) glass is an emerging material for engineering applications like protection and functional coatings. This material is very brittle and cannot stand mechanical loads. In this work, multi-wall carbon nanotubes were suggested as a reinforcing material to toughen the hybrid glass. Sol-gel method was used to prepare the hybrid glass (melting glass) by mixing two alkoxysilanes precursors, mono-substituted and di-substituted alkoxysilanes. Four weight ratios (0.0125, 0.025, 0.05, 0.25 wt%) of multi-wall carbon nanotubes were employed. The composite coatings were synthesized by mixing multi-wall carbon nanotubes with the sol once and with the gel another route. The mechanical, structural and functional properties to the yield composite films were characterized. The results showed that the addition of multi-wall carbon nanotubes to the hybrid glass has lowered the wettability of the resulting composite, where the maximum contact angle (θ) was 102°. Besides, existing of multi-wall carbon nanotubes in the matrix has increased the hardness of the hybrid glass to about 43 MPa at 0.0125 wt%. Correspondingly, the fracture toughness (kIC) has decreased in comparison to the hybrid glass alone. This refers to lower the glass ability to absorb the energy of fracture. The optical transmission has reduced as the weight ratio of multi-wall carbon nanotubes increased.

Creep Behavior of A356 Aluminum Alloy Reinforced with Multi-Walled Carbon Nanotubes by Stir Casting.

Lightweight aluminum alloy components are often used to manufacture a variety of engineering components in many industries. In recent years, researchers have studied the effect of improving the mechanical properties of metal alloys by incorporating nano-carbon into its structure. In this study, the effect of the addition of 0.2, 0.5, and 1 wt% of multi-walled carbon nanotubes (MWCNTs) on the stress-strain behavior and creep phenomenon of an A356 aluminum alloy were studied. The effect of nickel coating on 0.2 wt% MWCNTs was also investigated. Samples were prepared using the stir-casting method. The results revealed that the grain size became finer when MWCNT nano-particulates were introduced. Although the MWCNTs were distributed homogeneously in the A356 matrix, as confirmed by FESEM analysis, there were some agglomerations observed in a specific area with dimensions smaller than 100 nm. Nevertheless, the addition of MWCNTs was found to be beneficial in enhancing the hardness of alloys containing 0.2 wt%, 0.2 wt% nickel-coated, 0.5 wt%, and 1 wt% MWCNTs by 9%, 24%, 32%, and 15%, respectively, as compared with the unreinforced A345 matrix. It was also found that the 0.5 wt% MWCNT-A356 matrix exhibited an improvement in the creep lifetime by more than two orders of magnitude.

Development of nanomodified self-healing mortar and a U-Net model based on semantic segmentation for crack detection and evaluation

In this study, a cement-based self-healing (SH) mortar mixed with multiwalled carbon nanotubes (MWCNTs) was developed, and the effect of MWCNT addition on the electromechanical properties of mortar was studied. In addition, a deep learning based U-shaped Network (U-Net) model was adopted for the crack healing evaluation in SH mortar specimens. The trained U-net model is capable to detect the cracks with the accuracy of 99 %. The MWCNT content in the mortar was varied from 0.05 % to 0.10 % by weight of the cement. A minerals-based SH admixture was incorporated at concentrations of 2.5 %, 5 %, and 7.5 % by weight of cement. Compression and flexural strength tests were performed to investigate the mechanical performance of the nanomodified mortar. Piezoresistive sensing properties of MWCNT/cement composite were monitored during flexural test. For crack healing evaluation, cracked mortar prisms were exposed to water for 28 days. Mechanical and piezoresistive sensing evaluation demonstrated improved mechanical performance of SH mortar with appreciable self-sensing properties. Specimens with 2.5 % admixture exhibited a crack sealing efficiency of approximately 90 %, while the cracks in specimens with 5 % and 7.5 % SH admixture content healed 100 % after 28 days of water exposure.

The Injected Foaming Study of Polypropylene/Multiwall Carbon Nanotube Composite with In Situ Fibrillation Reinforcement.

This paper explored the injection foaming process of in situ fibrillation reinforced polypropylene composites. Using polypropylene (PP) as the continuous phase, polytetrafluoroethylene (PTFE) as the dispersed phase, multi-wall carbon nanotubes (MWCNTs) as the conductive filler, and PP grafted with maleic anhydride (PP-g-MA) as the compatibilizer, a MWCNTs/PP-g-MA masterbatch was prepared by using a solution blending method. Then, a lightweight, conductive PP/PTFE/MWCNTs composite foam was prepared by means of extruder granulation and supercritical nitrogen (ScN2) injection foaming. The composite foams were studied in terms of rheology, morphological, foaming behavior and mechanical properties. The results proved that the in situ fibrillation of PTFE can have a remarkable effect on melt strength and viscoelasticity, thus improving the foaming performance; we found that PP/3% PTFE showed excellent performance. Meanwhile, the addition of MWCNTs endows the material with conductive properties, and the conductivity reached was 2.73 × 10-5 S/m with the addition of 0.2 wt% MWCNTs. This study's findings are expected to be applied in the lightweight, antistatic and high-performance automotive industry.

Implementation of Passing Vehicle Search Algorithm for Optimization of WEDM Process of Nickel-Based Superalloy Waspaloy.

Nickel-based superalloys find their main use in missile engines, atomic devices, investigational aircraft, aerospace engineering, industrial applications, and automotive gas turbines, spacecraft petrochemical tools, steam power, submarines, and broader heating applications. These superalloys impose certain difficulties during the process fabrication owing to their levels of higher hardness. In the current study, the precise machining of Waspaloy was attempted through the wire electrical discharge machining (WEDM) technique. A multi-objective optimization has been performed, and the influence of multi-walled carbon nanotubes (MWCNTs) has been assessed using the passing vehicle search (PVS) algorithm. The effects of machining variables like current, Toff, and Ton were studied using the output measures of material removal rate (MRR), recast layer thickness (RLT), and surface roughness (SR). The Box-Behnken design was applied to generate the experimental matrix. Empirical models were generated which show the interrelationship among the process variables and output measures. The analysis of variance (ANOVA) method was used to check the adequacy, and suitability of the models and to understand the significance of the parameters. The PVS technique was executed for the optimization of MRR, SR, and RLT. Pareto fronts were derived which gives a choice to the user to select any point on the front as per the requirement. To enhance the machining performance, MWCNTs mixed dielectric fluid was utilized, and the effect of these MWCNTs was also analyzed on the surface defects. The use of MWCNTs at 1 g/L enhanced the performance of MRR, SR, and RLT by 65.70%, 50.68%, and 40.96%, respectively. Also, the addition of MWCNTs has shown that the machined surface largely reduces the surface defects.

Density functional theory and experimental investigations of MWCNT-PDMS based triboelectric nanogenerator

The emergence of triboelectric nanogenerators (TENG) have transformed the landscape of self-powered electronics and sensing mechanisms by exploiting the remarkable potential of innovative functional nanomaterials. However, there is a lack of theoretical in-depth analysis of the triboelectric devices. Herein, for the first time, the triboelectric performance of Polydimethylsiloxane (PDMS) and Multi-walled Carbon Nanotubes (MWCNT) - PDMS based TENG is unveiled by rigorous investigation of electronic structures through density functional theory (DFT) computations. Experimentally, PDMS and MWCNT-PDMS thin films are fabricated that are used as tribo-negative layers in the fabrication of TENGs. Further, the material characterisations are performed for the fabricated nanocomposite films. The output performance of TENGs is realised by using a dynamic test platform that imitates the finger tapping mechanism and the influence of contact surface area (1 cm 2 , 4 cm 2 , 9 cm 2 , 16 cm 2 , 25 cm 2 ) between triboelectric layers on open circuit voltage (V oc ) of TENGs is investigated. The outcomes demonstrate linear increase in V oc corresponding to increase in contact area of TENG. With a contact area of 1 cm 2 , the maximum peak-to-peak open circuit voltage (V mpp ) is recorded to be 32.2 V and 94.2 V for PDMS and MWCNT-PDMS based TENG respectively. An increase in V mpp by ~65% is synergistically validated by ~95% decrease in band gap endowing to addition of MWCNT into PDMS elastomer. Importantly, the energy band gap analysis is quantified by calculating HOMO/LUMO states and density of states responsible for the development of electric potential which can be used for small power applications. • Analysing the enhancement in triboelectric performance of PDMS on addition of MWCNT using density functional theory (DFT) calculations. • MWCNT-PDMS based TENG exhibited ~65% higher open circuit voltage than pure PDMS TENG. • Band gap reduced by ~95% on incorporation of MWCNT into PDMS elastomer. • Increased DOS peak intensity in valence band and conduction band along with the shift towards fermi level provides assistance to charge transport in comparison to pristine PDMS • Experimental outcomes are synergistically validated by DFT findings.

Graphene- and MWCNT-reinforced magnesium oxychloride composite modified by tannic acid

New multi-component composites based on Magnesium Oxychloride Cement (MOC) were developed as an alternative to commonly used construction materials. In this study, the MOC matrix was modified by the addition of tannic acid, graphene, and multi-walled carbon nanotubes (MWCNT). The prepared samples were analyzed in detail with a focus on micro- and macrostructural parameters, phase composition, and assessment of physical and mechanical properties. The influence of tannic acid addition on the hygric parameters and softening coefficient was also studied in detail. The results confirmed that the application of the carbon–based nanomaterials even in a very low amount significantly improved the mechanical properties of the multi-component composites. Interestingly, the addition of tannic acid led to an improvement in mechanical performance as well as water resistance. It was also demonstrated that the material porosity dramatically decreased with the application of dopants. The developed composites with improved material properties will find applications mainly in the construction industry.

Effect of addition of MWCNTs to a mineral lubricant on Diesel engine performance

In this research, a diesel engine lubricant, modified with Multi-Walled Carbon Nanotubes (MWCNTs) was evaluated. Carboxylic group functionalized MWCNTs were dispersed in 15W40 mineral oil for Diesel engines and retaining ring and cylinder sleeve materials from F300 diesel engine were used for tribological tests. The Nanofluid (0.1 0.5 and 1% wt.) rheological behavior was characterized. Nanolubricants with 1% wt and base oil were evaluated on a Pin-on-Disk test. Results suggest both wear rate and coefficient of friction reduction when MWCNTs are used, while no significant rheological properties changes were observed.

A sustainable biochar-based shape stable composite phase change material for thermal management of a lithium-ion battery system and hybrid neural network modeling for heat flow prediction

Electric vehicles are gaining global popularity lately, and along with it, efficient battery thermal management systems (BTMS) are also gaining traction amongst the research community. Phase change material (PCM) based BTMS can be an attractive solution due to its high energy density and isothermal energy exchange. However, pure PCM has some drawbacks like low thermal conductivity, volume expansion, and leakage during phase change. A shape stable composite PCM (SSCPCM) resolves these drawbacks but is an expensive solution due to the high cost of conventional supporting materials. Biochar (BC) based SSCPCM developed in this study can be a cheap and sustainable solution for BTMS. The characterization studies are carried out for combination of pure PCM (Myristyl Alcohol) and biochar at various loadings of 6 %, 12 %, 18 %, and 24 % by weight, using Fourier transform infrared analysis (FT-IR), X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), particle size analysis (PSA), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The shape stability studies reveal that the PCM with minimum of 24 % biochar (PCM-BC24) is shape stable. The thermal conductivities and effusivities of pure and shape-stable composite PCMs are also studied. Enhancement in thermal conductivity of PCM-BC24 is studied with the addition of multi-walled carbon nanotubes (MWCNT) in 0.5 % and 1 % concentrations. FT-IR and XRD results reveal that the interaction of biochar and MWCNT with pure PCM is purely physical and chemically stable. The degree of supercooling is reduced by 19.26 %, 23.49 %, and 25.17 % for PCM-BC24 with 1 % MWCNT compared to pure PCM at a heating rate of 5.0, 7.5, and 10 °C/min, respectively. Thermal conductivity and effusivity of PCM-BC24 with 1 % MWCNT are 458.72 % and 146.25 % higher than the pure PCM, respectively. The TGA results reveal that PCMs thermal stability is not adversely affected by the addition of BC & MWCNT. Furthermore, an ANFIS model is developed to predict the heat flow (mW/mg) values of PCM samples and found that the generalized bell-shaped input and linear output membership function is best suitable with a coefficient of determination (R2) of 0.971.

A comparative study of GNPs and MWCNTs additives on dispersion behavior and strength characteristics of the adhesively bonded joints

In this research, the effects of graphene nanoplatelets (GNPs) and multi-walled carbon nanotubes (MWCNTs) inclusion at various weight fractions (0.25, 0.5, 0.75, and 1 wt%) on the dispersion behavior and strength characteristics of adhesively bonded joints were experimentally investigated and compared. For uniform dispersion of GNPs and MWCNTs across adhesive, an extensive solution mixing technique was carefully carried out. Two types of lap joints, that is, single lap joint (SLJ) and double strap joint (DSJ) were prepared using the neat and modified adhesive. The joints were fabricated using Al 5083 as adherends. A comparison of the strength properties was made after tensile testing of the lap joints. A substantial increase in the strength properties was observed with the added GNPs and MWCNTs. However, the strength response depicted by MWCNTs was superior to GNPs. A maximum improvement of 60% and 31% in lap shear strength was observed for SLJ and DSJ, respectively. This improved response was depicted at 1 wt% of MWCNTs addition in the adhesive. Fourier-transform infrared spectroscopy (FTIR) and ultraviolet–visible spectroscopy (UV–Vis-Nir) were utilized for chemical and dispersion analysis. Digital and scanning electron microscopy techniques were utilized in close examination of the fracture surfaces at high magnifications. Finally, a comprehensive discussion on the difference in strengthening mechanism between the two nanofillers was critically discussed.

Effects of the addition of multi-walled carbon nanotubes on the microstructure and properties of Ti(C,N)-based cermets prepared by spark plasma sintering

To improve the toughness of Ti(C,N)-based cermets, multi-walled carbon nanotubes (MWCNTs) and nano-WC were added, and spark plasma sintering (SPS) technology was applied. The effects of the addition of MWCNTs on the phase composition, microstructure, and the comprehensive properties of Ti(C,N)-based cermets were investigated. The results show that the cermet (0.4 wt% MWCNTs) prepared by SPS (1350 °C, 16 min, and 35 MPa) has uniform microstructure and excellent comprehensive properties. The hardness and fracture toughness of this sample reach maximum values of HV 3050.29 and 10.90 MPa·m1/2, respectively. Compared with the sample without MWCNTs, the values are increased by 82.57% and 105.66%, respectively. A small number of carbon atoms from the MWCNTs enter the lattice of Ti (C,N) solid solution, which is conducive to improving the bonding ability and high-temperature wettability between MWCNTs and the matrix, thus enhancing the strength and toughness of the matrix materials. The addition of MWCNTs plays a bridging and toughening role at different interfaces. Moreover, the addition of nano-WC is conducive to the plastic flow and particle rearrangement of hard particles at high temperature.

Sacrificial Template Method to Fabricate Highly Sensitive Porous Capacitive Pressure Sensor for Full Pulse Waveform Detection

Due to the recent advancements in sensing technology, skin mountable wearable devices have gained much attention due to their non-invasive usage and wearer comfort for health care monitoring. For instance, monitoring pulse waveform from the wrist arterial sites bears tremendous information about cardiovascular health and can show abnormalities such as hypertension or arterial fibrosis. Acquiring a high-quality pulse waveform from the wrist artery requires high-pressure sensitivity and fast response time. However, the need for building highly sensitive and low-cost fabrication of the sensors for subtle physiological monitoring is still challenging. Targeting these issues, this study presents a facile and cost-effective approach to realizing a flexible capacitive pressure sensor by sandwiching porous polydimethylsiloxane (PDMS) polymer functionalized by multi-walled carbon nanotubes (MWCNTs) fabricated by sacrificial template method for physiological monitoring. The fabrication steps for the dielectric layer involve mixing sucrose as the porogens and MWCNTs as the functionalizing material with PDMS followed by casting the mixture in a mold and curing of the PDMS. Subsequently, the sucrose particles are dissolved in water. The sucrose particles are easily dissolved in water leaving a highly uniform and porous structure behind. The dielectric layer is then sandwiched between two conductive textile based electrodes for physiological monitoring. The electromechanical tests were performed for different concentration of MWCNTs content in porous PDMS to obtain the best sensing performance. The champion sensor exhibits ultrahigh-pressure sensitivity of 2.41kPa-1 and a minimum detection limit of 1.4Pa in contrast to the sensor exhibiting only 0.31kPa-1 without addition of any MWCNTs. In addition, the pressure sensor shows a fast response time of 0.18s and excellent cyclic stability over 6000 cycles. The ultrahigh-pressure sensitivity comes from the addition of conductive MWCNTs filler that increases the dielectric permittivity. The highly porous structure of the polymer reduces the typical viscoelastic effects of polymer resulting in fast response time. The pressure sensor could detect arterial pulse waveform from the wrist artery with all the key characteristic points showing its promises for low-cost physiological monitoring. The detailed results will be discussed during the presentation.

Nonwoven Mats Based on Segmented Biopolyurethanes Filled with MWCNT Prepared by Solution Blow Spinning.

To prepare nonwoven mats constituted by submicrometric fibers of thermally responsive biopolyurethanes (TPU) modified with multiwalled carbon nanotubes (MWCNT), solution blow spinning (SBS) was used. The TPU was the product of synthesis using poly(butylene sebacate)diol, PBSD, ethyl ester L-lysine diisocyanate (LDI), and 1,3-propanediol (PD) (PBSe:LDI:PD) as reactants. TPU was modified by adding different amounts of MWCNT (0, 0.5, 1, 2, and 3 wt.%). The effect of the presence and amount of MWCNT on the morphology and structure of the materials was studied using field-emission scanning electron microscopy (FESEM) and Fourier-transform infrared spectroscopy (FTIR), respectively, while their influence on the thermal and electric behaviors was studied using differential scanning calorimetry (DSC) and capacitance measurements, respectively. The addition of MWCNT by SBS induced morphological changes in the fibrous materials, affecting the relative amount and size of submicrometric fibers and, therefore, the porosity. As the MWCNT content increased, the diameter of the fibers increased and their relative amount with respect to all morphological microfeatures increased, leading to a more compact microstructure with lower porosity. The highly porous fibrous morphology of TPU-based materials achieved by SBS allowed turning a hydrophilic material to a highly hydrophobic one. Percolation of MWCNT was attained between 2 and 3 wt.%, affecting not only the electric properties of the materials but also their thermal behavior.

Investigation of the thermal conductivity enhancement mechanism of polymer composites with carbon-based fillers by scanning thermal microscopy

In order to elucidate the mechanism of enhancement of heat transfer in polymer composites, in this work, we investigated two types of polymer-carbon filler composites. This investigation was made using scanning thermal microscopy (SThM) with the Wollaston microprobe operated in active mode as a function of the carbon filler weight fraction within the polymer matrix. Samples consist of high-density polyethylene (HDPE) filled with 50 µm expanded graphite (EG) and polyvinylidene difluoride (PVDF) containing multiwall carbon nanotubes (MWCNTs). For HDPE/EG samples, SThM images allow the detection of zones with a thermal conductance larger than that of the matrix for the highest studied filler concentration. These zones correspond to EG filler agglomerations within the polymer and explain the observed enhancement of the thermal conductivity k of the HDPE/EG composite. For PVDF/MWCNTs samples, it is found that k increases from 0.25 W m−1 K−1 for pristine PVDF to 0.37 W m−1 K−1 for PVDF nanocomposites filled with 8 wt. % MWCNTs. This k variation vs filler concentration is found in good correspondence with that of the β phase relative percentage in the PVDF nanocomposites. This suggests that the observed heat transfer enhancement is rather due to the formation of β phase for PVDF/MWCNTs samples, resulting from the addition of MWCNTs than the addition of MWCNTs itself. Thus, tuning the thermophysical properties of polymer-based nanocomposites can establish new design laws to confer them specific thermal properties.

Evaluation of MWCNT as fuel additive to diesel–biodiesel blend in a direct injection diesel engine

In this study, effects of multi-walled carbon nanotube (MWCNT) addition to waste frying oil biodiesel (B20) on performance, combustion, and exhaust emissions in a direct-injection compression ignition engine were investigated. Experiments were carried out at maximum engine torque speed and four different engine loads. The results show that engine performance has deteriorated somewhat by using B20 fuel without MWCNT additive compared with neat diesel. The addition of MWCNT to B20 improved fuel properties. This occurred because MWCNT additive improved engine performance. By using 100 ppm additive to B20 fuel, the combustion duration has been shortened compared to neat diesel, indicating that thermal efficiency has increased with the decrease of heat losses. The highest indicated thermal efficiency was recorded as 33.16% at 15 Nm engine load using 100 ppm additive to B20 test fuel. Also, 100 ppm additive to B20 test fuel reduced hydrocarbon, CO and soot emissions by 41, 36.4 and 31.8%, respectively, compared to reference neat diesel fuel. The MWCNT additive improved the in-cylinder combustion reactions, thereby increasing engine performance. With the improvement of combustion, in-cylinder gas temperatures increased. For this reason, higher NOx emissions were obtained using MWCNT additive fuels compared to neat diesel.

Role of adding carbon nanotubes in the electric and electromagnetic shielding behaviors of three different types of graphene in hybrid nanocomposites

Graphene-related materials (GRM) are promising materials to improve mechanical, electrical, and optical polymer properties. Adding multi-wall carbon nanotubes (MWCNT) on GRM nanocomposites promotes synergistic effects on its electrical properties and electromagnetic interference shielding effectiveness (EMI SE). This study focused on evaluating the addition of MWCNT on three different polycarbonate (PC)/acrylonitrile butadiene styrene (ABS)/GRM nanocomposites. These hybrid nanocomposites were prepared by melt mixing using extrusion and injection-mold processes. The morphologies of the nanocomposites were evaluated by field emission gun scanning electron microscopy (FEG-SEM), and their proprieties were characterized by X-ray diffraction (XRD), oscillatory rheological, dielectric spectroscopy, and EMI SE analyses. The electrical behavior of all hybrid nanocomposites was anisotropic due to the injection-molded preparation process. The lateral size, thickness, and production method of the GRM were indicated to be critical factors for the electrical and EMI SE behaviors of these composites. The nanocomposites with GRM2, which had the smallest lateral size and thickness (graphene nanoplatelets), promoted total attenuation levels around 20 dB with 1.5 wt% of MWCNT, matching the EMI SE required for some commercial applications.