Addition Of CNT Research Articles

Photoinduced modulation and the effect of CNT loading on field effect transistor characteristics of CNT/ZnO/PVDF composite.

CNT/ZnO/PVDF polymer composite phototransistor is studied for the effect of CNT loading and the photoinduced modulation on its transfer characteristics. XRD study shows that the induced strain in the composite is due to the addition of CNT to the ZnO/PVDF composite. The percentage of β-phase present in PVDF is estimated through Raman spectroscopy and the composite's spectral response is determined by UV-Vis absorbance spectroscopy. From the DC electrical conductivity study it is found that the percolation threshold for the composites is obtained for 0.3 wt% of CNT, and 0.44 wt % of CNT loading makes the composite conductive. On adding 1 wt% of CNT, the electrical conductivity of the ZnO/PVDF composite increases 40 times (~ 0.2 μS/m). The temperature-dependent DC conductivity shows that the conductivity of the composites changes from variable range hopping (VRH) to band conductance upon an increase in CNT loading above the percolation threshold and exhibits a negative temperature coefficient (NTC). Two terminal photoconductivity studies are done to understand the photo enhancement and sensitivity of all the devices. PE hysteresis studies show that the polarization of the composites increases drastically from 0.05 μC/cm2 below the percolation threshold to 10 - 30 μC/cm2 above the percolation threshold of CNT in the composite. To study the effect of interfacial polarization on photoconductivity, the composite is studied in a three-terminal device format using SiO2 as a gate dielectric. A band diagram analysis of the oxide-composite and CNT/ZnO interface is done to understand the mechanism behind the photoinduced field effect on transfer characteristics and the effect of CNT loading. The switching behavior and decay time under UV illumination are studied to understand the effect of CNT loading and photoinduced polarization. The persistent photoconductivity decreases and the charge collection efficiency of the FET increases as the CNT loading increases.

Plasticized PVC composites comprising MWCNT‐RGO hybrid filler–the synergetic effect of hybrids on the dielectric and mechanical properties

AbstractModification of polymers with hybrid fillers has sought much attention in the past few years. The addition of hybrid fillers will lead to a synergistic effect in reinforcing and is advantageous in polymer nanocomposites. One such attempt is presented here that explores the effect of incorporation of hybrid derived from reduced graphene oxide (RGO) and multiwalled carbon nanotubes (MWCNT) on the dielectric and mechanical properties of plasticized polyvinyl chloride (PPVC). This system of hybrid composite incorporating RGO‐CNT and PPVC has not been prepared and reported yet. Melt mixing techniques were effectively used for the fabrication of PPVC nanocomposites containing the hybrid filler in different ratios. The prepared composites showed enhanced dielectric strength in the lower frequency region up to 450 and high AC conductivity. The mutual stacking and penetration of the 1D‐2D nanomaterials lead to effective dispersion and enhancement in the electronic conduction. Among the hybrids, the R1C5 (with the filler ration RGO 1 wt% and CNT 5%) was having the optimum properties. The tensile modulus showed a cumulative variation with the addition of CNT. Even though the tensile strength decreased slightly because of the immobilization of the PPVC chains by the hybrid effect, the modulus value showed a marked increase of over 90% from the virgin polymer. The PPVC composite with R1C5 hybrid filler exhibited an EMI shielding efficiency of ⁓23 dB and it was frequency independent. The results suggest the composite R1C5 should be used as a cost‐effective material for applications in the L‐band and S‐band regions.

Design of Experiment Is All You Need: Utilizing AI for High-Entropy Alloy Water Splitting Catalyst

High-entropy alloy (HEA) is a new group of material that have excited both fields of electrochemistry and computational chemistry, based on its intriguing concept and outstanding catalytic activity. Nevertheless, there exists a clear limitation to the 'trial-and-error' based research: its compositional space is too large. Therefore, AI-based high-throughput research is considered as an efficient way to optimize the composition of HEA electrocatalysts. To fully utilize AI's potential, the quality of data and rational Design of Experiment (DoE) is of importance. In this regard, we have 1) developed an automated one-step synthesis method of HEA with liquid handler and 2) made machine learning model with Gaussian process (GP) regression to minimize the overpotential (fig. 1a).DoE helps developing a new experiment by categorizing the variables and steps that are necessary. First step of DoE is to start with listing the variables. For the one-step synthesis of HEAs, independent variable was the composition of each elements, where the control variables were:A. Solvent (Amine/ethanol)B. Addition of CNT (O/X)C. Reaction temperature (high/low)D. Reaction time (long/short)E. Concentration of solution (5 mM / 10 mM)Each of control variables have two options and the selection is represented by writing an alphabet. For example, if amine (A) and high reaction temperature (C) condition was selected while the second option is used for the rest, it is written as AC. Based on confounding method theory, by conducting AC experiment, we also get information about BDE experiment by assuming a negative correlation to each other. It is written as: AC = -BDE. Similarly, an equivalent combinatorial list can be made for every possible combination (=25) , while the number of experiment is reduced from 32 to 16. Among these combinations, ABCE was found to be optimal synthesis condition (fig.1b).Afterward, we searched the optimal composition of HEAs, starting with grid searching the six-dimensional compositional field. MnFeCoNiCuMoPdPt - octonary alloy was the targeted alloy where the compositions of noble metal were fixed. Binomial distribution design was used to make the distance between neighboring points in 6-dimension compositional space equal (fig. 1c-d). 8C3 = 56 combinations were selected and consequently, the corresponding amounts of precursor solutions were transferred to 56 heat-inert vials and underwent heat treatment of 200 °C. Overpotential of 56 samples were measured and simple GP regression model was constructed based on these datasets.GP regression is composed of two parts: exploration and exploitation. During exploration, the optimal combination is recommended by searching the point that has the largest deviation. Interestingly, by comparing the Shapley Additive explanations (SHAP) value of each elements, it is clearly proved that Cu was harmful and Ni was beneficial to water splitting performance. Thus, Cu was screened out during the end of the exploration step. After finishing exploration, the next combination was recommended by searching near the point with least overpotential (exploitation step). By using GP regression, the optimal composition among HEAs was discovered in less than 200 experiments. It showed the overpotential less than 30mV for HER and less than 250mV for OER, making the overall water-splitting potential less than 1.5 V. In summary, a GP regression model showed synergistic effect with DoE, and HEA with the optimal composition showed an outstanding water splitting performance, reducing overall overpotential by 50% compared to the first step. Figure 1

Tailoring hierarchical structures in cellulose carbon aerogels from sugarcane bagasse using different crosslinking agents for enhancing electrochemical desalination capability

Sugarcane bagasse is one of the most common Vietnamese agricultural waste, which possesses a large percentage of cellulose, making it an abundant and environmentally friendly source for the fabrication of cellulose carbon aerogel. Herein, waste sugarcane bagasse was used to synthesize cellulose aerogel using different crosslinking agents such as urea, polyvinyl alcohol (PVA) and sodium alginate (SA). The 3D porous network of cellulose aerogels was constructed by intermolecular hydrogen bonding, which was confirmed by Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and nitrogen adsorption/desorption. Among the three cellulose aerogel samples, cellulose – SA aerogel (SB-CA-SA) has low density of 0.04 g m−3 and high porosity of 97.38%, leading to high surface area of 497.9 m2 g−1 with 55.67% micropores of activated carbon aerogel (SB-ACCA-SA). The salt adsorption capacity was high (17.87 mg g−1), which can be further enhanced to 31.40 mg g−1 with the addition of CNT. Moreover, the desalination process using the SB-ACCA-SA-CNT electrode was stable even after 50 cycles. The results show the great combination of cellulose from waste sugarcane bagasse with sodium alginate and carbon nanotubes in the fabrication of carbon materials as the CDI-utilized electrodes with high desalination capability and good durability.

PENGECORAN ALUMINIUM MATRIKS KOMPOSIT BERPENGUAT CARBON NANOTUBE (CNT) DENGAN VARIASI PENAMBAHAN SERBUK MAGNESIUM

Aluminum matrix composite reinforced CNT have been developed to improve the mechanical properties of aluminum. In this study, the melting of Aluminum 1100 reinforced Carbon Nanotube (1 wt.% CNT) with variations in the addition of Magnesium powder was carried out by the slurry-based method. The casting of the specimens is carried out using a metal mold. CNT powder was first mixed with magnesium powder at 60°C. Then the aluminum is melted to a temperature of 700°C until it melts, then the temperature is lowered to 500°C or the texture has changed to be like mush (slurry based) and then mixed with CNT powder and Magnesium powder are added. After that the alloy was raised again at 720°C for 30 minutes and the stirring process was carried out, after that it was poured into a metal mold with a mold temperature of around 400°C. The samples were then analyzed for mechanical properties and microstructure observations. The results of the Vickers hardness test before the addition of Mg powder and CNT were 36.7 HV. While after the variation of adding 1wt.% Mg powder, the hardness of the specimen increased to 44.5 HV, the variation of adding 3% Mg powder was 45.3 HV, and the variation of adding 5% Mg powder reached a hardness value of 46 HV. The tensile test results on 3% Mg powder is 241.6 MPa. The wear test results show the wear rate value for the 1% Mg variation of 0.146 mg/s, the 3% Mg variation of 0.106 mg/s, and the 5% Mg variation with a wear rate value of 0.093 mg/s. The α-Al phase is the dominant phase formed, where the grain size and grain boundaries in the 3% Mg variation have a relatively small size and the spread of CNT is evenly distributed in the alloy, so the addition of Mg to the alloy can help spread CNT in Aluminum alloys.

Composite phase change materials with thermal-flexible and efficient photothermal conversion properties for solar thermal management

Composite phase change material (CPCM) with the advantages of high enthalpy and constant temperature phase change, has been widely used in many fields, such as photovoltaic thermal system, building envelope structure and so on. However, conventional CPCM is often rigid, poor light absorption and low thermal conductivity, which limits the application of solar energy utilization. In this paper, a novel Paraffin wax/Thermoplastic elastomer/Carbon nanotube(PA/SEBS/CNT) with shape stability, thermos-flexibility and high photothermal conversion efficiency was prepared, PA as the phase change material, SEBS as the flexible material and CNT as the light-absorbing material. The results show that the addition of CNT increases the absorbance of PA/SEBS from 0.3 to 1.0, and the photothermal conversion efficiency of PA/SEBS/CNT-10 % is as high as 96.17 %. In addition, the CPCM also has a high enthalpy value of 180 J/g, and a high thermal conductivity of >0.3403 W/(m·K), and also exhibits shape-driven memory. At the same time, outdoor photothermal experiments show that PA/SEBS/CNT has excellent photothermal conversion performance under real sunlight, and the highest temperature can reach 99.51 °C. The new CPCM developed has a broad application prospect in solar thermal systems.

Anticorrosion mechanism of ethylene-chlorotrifluoroeethylene coatings reinforced with hydroxylated carbon nanotubes: An experimental and molecular dynamics simulation study

Carbon nanotubes/ethylene-chlorotrifluoroeethylene (CNT/ECTFE) composite coatings were prepared on the surface of carbon steel via electrostatic spraying and low temperature heat treatment. The influence of hydroxylated carbon nanotubes on the anticorrosive properties of ECTFE coatings during water penetration stage was investigated through characterization tests of the coating micromorphology, phase structure, hydrophilicity/hydrophobicity, microhardness and electrochemical corrosion performance. Additionally, simulation analysis of the coating internal structure and water molecular infiltration law by molecular dynamics was conducted. The results indicate that the addition of CNT can augment the efficacy of ECTFE coating against water penetration, thereby improving the corrosion protection performance. This is primarily attributed to the ability of CNT to reinforce structural stability by impeding the free movement of ECTFE molecular segments and obstructing water molecules from infiltrating. Meanwhile, the hydroxyl groups on the surface of CNT can capture a large number of water clusters through hydrogen bonding and restrict the infiltration of water molecules by occupying osmotic channels. In addition, CNT can prolong the penetration path of water through the labyrinth effect.

The impressive improvement of CoCrFeMnNi high entropy alloy mechanical properties and pitting corrosion resistance by incorporation of carbon nanotube reinforcement

CoCrFeMnNi high entropy alloy without carbon nanotube (referred to as HEA) and with 0.2 wt% CNT (called HEA + CNT) were successfully synthesized through mechanical alloying and subsequent spark plasma sintering. The samples' phase composition, microstructure, mechanical properties, and corrosion performance were investigated. XRD results showed that the addition of CNT leads to a decrease in crystallite size, reducing it from 209 nm in HEA to 190 nm in HEA + CNT. FESEM results revealed a relatively uniform distribution of smaller carbide phases in the structure of HEA + CNT sample. The addition of CNT increased the ultimate compressive stress (UCS) from 1850 MPa for HEA to 2510 MPa for HEA + CNT. Cyclic polarization results demonstrated higher pitting corrosion resistance in HEA + CNT nanocomposite, where the pitting potentials for HEA and HEA + CNT were equal to 0.127 and 0.201 V vs. SCE, respectively. The CNT addition promoted the repassivation process of the pits in HEA + CNT sample.

Pushing the Electrochemical Performance Limits of Polypyrrole Toward Stable Microelectronic Devices

HighlightsOptimizing the current collectors with rGO and the addition of CNT in PPy, and the structural pulverization is prevented significantly.Areal capacitances of 65.9 to 70 mF cm−2 are achieved for PPy-CNT@rGO microsupercapacitors (MSCs) with 79% capacitance retention after 10,000 cycles.The MSC-derived capacitive micro-strain sensor is capable of biosignals detection.The micro strain sensor is capable of detecting wide levels of applied strain with short response/recovery time and excellent reliability.

Bi-Porphyrins MOF with confinement and ion-attracting effects in concert with RuO2-doped CNT as efficient electrocatalysts for HER in acidic and alkaline media

It is highly desirable and challenging to design efficient and stable hydrogen evolution reaction (HER) electrocatalysts in a variety of acidic and alkaline media. Here, a novel ternary catalyst has been proposed consisting of ruthenium dioxide doped carbon nanotubes (denoted as RuO2@CNT) wrapped in a multi-step strategy with a first synthesis of a bismuth metal porphyrin-based organic framework as co-catalyst (denoted as RuO2@CNT@MOF). The addition of CNT improves not only the conductivity of the electrocatalyst but also the distribution of the active RuO2 particles. Furthermore, the highly symmetrical conjugated structure of Bi-TCPP MOF facilitates both the adsorption of hydrogen ions and the generation of hydroxyl radicals (•OH). The Bi-TCPP MOF encapsulated in the outer layer of RuO2@CNT enhances the mechanical strength and creates the confinement effect, leading to the synthesis of RuO2@CNT@MOF as a HER electrocatalyst that exhibits excellent catalytic performance and acid and base resistance. In particular, low overpotentials of 13 mV and 50 mV can be achieved to provide current densities of 10 mA cm−2 in alkaline and acidic media, respectively. Significantly, this work provides new ideas for the careful design and development of MOFs as co-catalysts to improve the overall performance of materials in energy-related fields.

Effect of annealing and carbon nanotube infill on the mechanical and electrical properties of additively manufactured polyether-ether-ketone nanocomposites via fused filament fabrication

The light-weight, high-strength poly-ether-ether-ketone (PEEK) and its composite materials are the ideal candidate for a plethora of engineering applications. However, the inherent high viscosity and melting temperature of PEEK pose great challenges for the extrusion-based 3D printing process, leaving a wide knowledge gap on the properties and functionalities of novel PEEK-based composites. In this work, the PEEK/CNT composite filaments with different CNT content ranging from 1 to 7 wt% are prepared by single-screw extruder and subsequently printed with a custom-made high temperature 3D printer. The effects of CNT content and annealing on the mechanical strength and electrical conductivity of the 3D printed parts are investigated in detail. The tensile test result shows that the presence of CNT significantly enhances the mechanical strength of the composite. With 7 wt% CNT content, the maximum tensile strength and elastic modulus reaches 107.7 MPa and 1908.0 MPa, respectively, which amounts to a rise of 27.4% and 17.0% compared with the neat PEEK sample. The annealing treatment is similarly effective in strengthening the printed composites. The addition of CNT is also found to greatly improve the electrical conductivity to the PEEK, reaching 101 S/m for 7 wt% CNT. With such superior electrical conductivity, the printed PEEK/CNT composite sample exhibits outstanding electromagnetic interference (EMI) shielding performance, reaching 32.4 dB. However, additional annealing treatment decreases the electrical conductivity as wells as EMI shielding performance. Such decrease is mainly attributed to the growth of the crystals during annealing, which expels the CNTs to the grain boundaries and leads to remarkable agglomeration, which disconnects the pervasive conductive networks. The finding in this work can provide insights on the new designs of PEEK composite feedstock materials and cultivate new 3D printing strategies targeted specifically for highly-functional, high-strength novel composites.

Exploiting mono‐ and hybrid nanocomposite materials for fused filament fabrication with acrylonitrile butadiene styrene as polymer matrix

AbstractAcrylonitrile butadiene styrene (ABS) based polymeric composites consisting of mono‐ and hybrid nano‐compounds, that is, graphene nanoplatelets (GNP's), multi‐walled carbon nanotubes (CNT's), and titanium dioxide (TiO2), are studied for fused filament fabrication (FFF). Rheological analysis in a screening step reveals that nanocomposites containing CNT result in a better nano‐filler dispersion within the matrix and enhanced matrix interaction. The addition of GNP and TiO2 leads to a better coalescence between the deposited filaments. For the actual FFF specimens, emphasis is on the tensile, flexural and impact properties as well as the void content. It is shown that the joint addition of GNP, CNT, and TiO2 gives rise to a remarkable synergistic effect, leading to an improved dispersion and an increased tensile modulus and strength of 3D printed ABS by 16 and 20%. Decreasing the layer thickness increases the mechanical properties of the materials, while the printing temperature does not lead to major variations of the mechanical properties, due to a dominant effect of the addition of nanoparticles. It is also shown that for well‐designed composites the slower sintering and higher void content is overruled by the reinforcement effect.

Mechanical Properties, Melting and Crystallization Behaviors, and Morphology of Carbon Nanotubes/Continuous Carbon Fiber Reinforced Polyethylene Terephthalate Composites.

Carbon nanotube/continuous carbon fiber reinforced poly(ethylene terephthalate) (CNT/CCF/PET) composites are prepared by melt impregnating. The effects of CF and CNT content on the mechanical properties, melt and crystallization behaviors, and submicroscopic morphology of CNT/CCF/PET composites are studied. The tensile test results show that the increase of CF and the addition of appropriate amount of CNT improved the tensile strength and tensile modulus of the composites. When the content of CNT is 1.0 wt% and the content of CF is 56 wt%, the properties of the composites are the best, with tensile strength of 1728.7 MPa and tensile modulus of 25.1 GPa, which is much higher than that of traditional resin matrix composites. The results of dynamic mechanical analysis (DMA) show that the storage modulus of the composites increased with the increase of CF and CNT content. In particular, the addition of CNT greatly reduced the loss modulus of the composites. Morphological analysis show that the addition of CNT improved the fiber–matrix interface of the composite, which changes from fiber pull-out and fracture failure to fiber matrix fracture failure, and the fiber matrix interface is firmly bonded. In addition, there are polymer coated CNT protrusions on the surface of the fiber was observed. The results of differential scanning calorimetry (DSC) show that the melting temperature and crystallization temperature of the composites increased with the increase of CF content. The addition of CNT had little effect on the melting temperature of the composites, but it further improved the crystallization temperature of the composites. The effect of CNT content on the crystallization kinetics of the composites is studied. The non-isothermal crystallization kinetics of the composites is described by Jeziorny’s improved Avrami equation. The results show that CNT has a great influence on the crystallization type of the composites. As a nucleating agent, CNT has obvious heterogeneous nucleation effect in the composites, which improves the crystallization rate of PET.

Effect of Carbon Nanotubes on the Mechanical, Crystallization, Electrical and Thermal Conductivity Properties of CNT/CCF/PEKK Composites.

Carbon nanotube/continuous carbon fiber–reinforced poly(etherketoneketone) (CNT/CCF/PEKK) prepreg tapes were prepared by the wet powder impregnation method, and then the prepreg tapes were molded into laminates. The effects of carbon nanotubes on the mechanical properties, conductivity, thermal conductivity and crystallinity of the composites were studied by universal testing machine, thermal conductivity and resistivity tester, dynamic mechanical analyzer (DMA) and differential scanning calorimeter (DSC). The results show that when the content of carbon nanotubes is 0.5 wt% (relative to the mass of PEKK resin, the same below), the flexural strength and interlaminar shear strength of the laminates reach the maximum, which are increased by 15.99% and 18.16%, respectively, compared with the laminates without carbon nanotubes. The results of conductivity and thermal conductivity show that the higher the content of carbon nanotubes, the better the conductivity and thermal conductivity of the material. DSC results show that the addition of CNT promoted the crystallization of PEKK in the material and decreased the cold crystallization of PEKK. DMA results show that the deformation resistance of the material can be improved by adding an appropriate amount of CNT and the bonding between CF and PEKK can be enhanced, while excessive CNT destroys this phenomenon.

Mechanical, microstructural and electrical properties of Al7075/SiC based hybrid composites with nano B4C, Graphene and CNT reinforcements

Superfluous properties of Graphene and CNT reinforced composites are making significant revolution in the application area of metal matrix nano-composites. Fabrication of these composites without any flaw is the challenging task due to its inherent properties such as limited wettability, unique structure, load transfer efficiency, shape and size. The individual reinforcements such as 0.1wt.% B4C, 0.1wt.% Graphene and 0.1wt.% CNT were successfully incorporated in common Al7075/10wt.% SiC base through squeeze casting method combined with ultrasonic vibration. The influence of reinforcements on the mechanical, metallurgical and electrical properties of the composites was analysed in this study. The hardness value of the B4C-based, Graphene-based and CNT-based composites has enhanced to 167 BHN, 145 BHN and 135 BHN respectively from the base matrix. Tensile strength has also improved to 239 MPa, 324 MPa and 308 MPa. In the case of micro-structural characteristics, the addition of Graphene in the Graphene reinforced composite improved the grain structure due to the grain refining effect followed by the CNT and B4C reinforced composites with the similar weight fraction and processing methods. The influence of various reinforcements was analysed using Optical Microscope (OM), Scanning Electron Microscope (SEM) and Energy-Dispersive X-ray analysis (EDX) techniques. Addition of Graphene and CNT increased the electrical conductivity of respective composites to 24.2 MS/m and 21.1 MS/m.

Supercritical Fluids-Assisted Processing Using CO2 Foaming to Enhance the Dispersion of Nanofillers in Poly(butylene succinate)-Based Nanocomposites and the Conductivity

With the rapid development of electronic information technology, traditional metal conductive materials can no longer satisfy the needs of a wider industry. Poly(butylene succinate)/multiwalled carbon nanotubes (PBS/CNT) conductive polymer nanocomposites with varied CNT content were prepared by a HAAKE torque rheometer. The addition of CNT significantly improved the crystallization, viscoelasticity, and mechanical properties as well as thermal and electrical conductivity. Conductivity of the PBS/CNT nanocomposite with 5 wt% CNT increased from 8.23 × 10–15 S m−1 of pure PBS to 33.3 S m−1, an increase of 16 orders of magnitude. Moreover, the electrical percolation threshold \({\mathrm{\varphi }}_{\mathrm{c}}\) of the PBS/CNT nanocomposites was 2.8 wt% and the critical index was 1.56, showing that the conductive network structure was between 2 and 3D and 2D network structure dominated. To further improve the conductivity, microcellular foams were successfully fabricated by batch foaming with supercritical fluids (scCO2). The electrical conductivity of the PBS/CNT foam with 5 wt% CNT reached 67.8 S m−1 and it was 104% higher than the corresponding solid nanocomposite.

Enhancing Seebeck coefficient and electrical conductivity of polyaniline/carbon nanotube–coated thermoelectric fabric

In this work, flexible thermoelectric fabrics, polyester/yarn fabrics coated with polyaniline/carbon nanotube (PANI/CNT) nanocomposite, were fabricated by sequential processing: (I) polyaniline/carbon nanotube nanocomposites preparation by a one-step in-situ polymerization and (II) dip coating of a mixture solution of CNT-doped PANI on a polyester/yarn fabric. Nanocomposites were synthesized with various CNT content (0.5, 2.5, 5, and 10 wt%) and characterized using different methods. The Seebeck coefficient and electrical conductivity measurements were used to determine their thermoelectric properties. The results revealed significant improvement in both electrical conductivity and the Seebeck coefficient with the addition of CNT. The electrical conductivity increased from 0.011 to 0.1345 S/cm with the increment of CNT from 0.5 to 10 wt%. The highest Seebeck coefficient of 11.4 μV/K was observed for the sample containing 5 wt% CNT at 338 K where the maximum power factor of 1.598×10−3 μWm−1K−2 was obtained for the fabric coated with nanocomposite containing 10 wt% CNT.

Novel carbon nanotubes reinforced copper composite electrode for improved performance of electric discharge machining

Composite electrode fabrication is an effective strategy to improve the performance of the Electric Discharge Machining (EDM) process. In this work, a new copper/carbon nanotube (Cu/CNT) metal matrix composite electrode at a different volume fraction of CNT (0.35%, 0.70% and 1.05%) is developed using a spark plasma sintering (SPS) method. The real-time functional performance of the developed electrode on the EDM machining is also examined by changing the EDM process parameters (discharge current, pulse-on time and voltage). The composite electrode characterization results indicated that as the percentage of CNT increases from 0.35 to 1.05 vol%, the density reduced and electrical resistivity increased due to the rise in porosity. Performance review of CNT-infused electrodes during EDM machining revealed a higher Material removal rate (MRR) and good surface finish than the Cu electrodes due to high discharge energy and enlargement in the spark gap. However, Cu/CNT electrodes wore out faster than Cu electrodes by 90%, possibly due to the reduction in thermal conductivity induced by porosity effects. Comprehensively, although the addition of CNT affected the mechanical attributes of the electrode, it offered significantly better output (MRR and Surface finish) than the Cu electrode with limitations on electrode wear.

Experimental studies on the effect of Carbon nanotube additives with Calophyllum Inophyllum biodiesel in CI engine

The rapid depletion of Non-renewable fuel sources coupled with environmental degradation, has led us further into the exploration of alternate energy resources. Biodiesels originating from non-edible feedstocks have garnered much attention in a span of few years. The current study focuses on the addition of Carbon Nanotubes in Tamanu oil biodiesel in a Diesel engine. In this study, parameters such as brake thermal efficiency, unburned hydrocarbon, carbon monoxide, and NOx emissions have been studied. The performance of these biodiesel-diesel blends were charted and results are compared with diesel. It is noted that the inclusion of nano-additives in dosages of 30 and 60 ppm enhances brake thermal efficiency, the drawback being increased specific fuel consumption. The emissions of HC, NOx and emissions show a favorable trend with addition of CNT but CO2 emissions were observed to be on the higher side. Also graphs were plotted revealing the relevant combustion characteristics of the test fuels. They are further discussed in detail and a comprehensive conclusion was made.

О влиянии углеродных нанотрубок на физико-механические свойства полипропилена

One of the most interesting and promising materials of our time is carbon nanotubes. Most applications of nanotubes are associated with the possibility of combining them with other materials in the form of alloys, mixtures, composites or hybrid materials. In particular, the idea of including carbon nanotubes as a filler in various polymer-based matrices (for example, traditional polymers such as thermoplastics, thermosetting materials or elastomers, as well as conjugated polymers) for the formation of polymer/carbon nanotube nanocomposites has revolutionized materials science and engineering. The introduction of carbon nanotubes into the composite structure affects the structure and properties of the polymer binder, as well as the composite material as a whole. Currently, there are no experimental developments on the basis of which the introduction, distribution and stabilization of the dispersion of carbon nanotubes in polymer composites would be implemented in industrial technology. The development of the most effective methods for introducing carbon nanotubes into polymer materials and determining their effect on the physical and mechanical properties of polymers is an urgent and priority task. It is possible that these methods will be able to find application in the industrial production of polymer composite materials intended for use and operation in various extreme conditions (whether it is high temperatures, erosion, high force exposure or highly acidic/highly alkaline environments). The main physical and mechanical properties of polypropylene samples saturated with carbon nanotubes taken at different concentrations (0; 0.01; 0.05 and 0.1 wt. %), who found that the addition of CNT in large quantities negatively affects the tensile and bending strength limits, which may be associated with an increase in the degree of heterogeneity of the structure and the appearance of large agglomerates, which will be points of stress concentration. With an increase in the mass fraction of carbon nanotubes in the polymer nanocomposite, the tangent of the dielectric loss angle increases, which leads to better conductivity of the sample containing a larger number of nanotubes. This may be due to the fact that nanotubes become conductors of electric current in the volume of the polymer matrix.