Vertically Aligned Multi-walled Carbon Nanotubes Research Articles

Dryout suppression and significantly enhanced flow boiling heat transfer through the two-tier vertically aligned carbon nanotube channel

It is crucial to design multi-functional structure to improve heat transfer characteristics. Here we report significantly enhanced saturated flow boiling heat transfer of water using the two-tier vertically aligned multiwalled carbon nanotube (VAMWNT) channel (tube diameter: 11.5 nm). The channel size is 10 × 10 × 2 mm3 (height: 2 mm). The tube aggregation-generated large voids act as micropores (10-200 µm) whereas the interstitial spaces between the tubes act as nanopores (< 72 nm). The microcavities at the periphery of aggregated nanotubes increase bubble nucleation sites while constraining bubble size. The high nanotube thermal conductivity induces more uniform bubble nucleation, and departed bubbles are swept away through the micropores. On the other hand, water is effectively replenished through the nanopores by high capillary pumping. Overall, the path separation of bubble departure and water replenish effectively prevents dryout and increases critical heat flux (CHF). The experiment is carried out at 3 different mass velocities (62, 83, and 104 kg m−2 s−1). The VAMWNT channel provides a high heat transfer coefficient (h = 100,666 W m−2 K−1 at 183 W cm−2), even before reaching CHF without any sign of local dryout, compared with microchannels and porous media in literature (under the similar heat flux and mass velocity). In contrast, the CHF condition is observed for a plain channel of the same size without the nanotubes, resulting in smaller h values than those of the VAMWNT channel. The novel two-tier structure separated liquid-vapor pathways, significantly enhancing heat transfer characteristics.

Vertical alignment of carbon nanotubes in photo-curable polymer for multi-functional hybrid materials

Carbon nanotubes (CNTs) are nanomaterials with excellent mechanical strength, electric conductivity, and low weight. Interestingly, vertically aligned CNTs show much higher mechanical and electrical properties than randomly networked CNTs, because CNTs are much more resistant to axial impacts than lateral impacts; this study suggests an efficient process to produce vertically aligned multi-walled carbon nanotubes (VA-MWNT)-photocurable polymer hybrid materials. VA-MWNTs can fortify the mechanical properties of polymer composites even with very small amounts of MWNTs in the composite. Previous studies have produced VA-MWNT–polymer hybrid materials by coating polymers on MWNT forests synthesized in the vertical direction. However, this method cannot be extended to the large-scale production of hybrid polymers because of the limited area of substrates for the synthesis of the MWNT forests, and because the synthesis requires a complex and expensive process. We arranged MWNTs in the vertical direction in VA-MWNT-polymer mixtures in a short process via electrophoresis. Subsequently, UV irradiation for a few minutes completely cured the photocurable polymer while the MWNTs were fixed in the vertical direction. The VA-MWNT-polymer showed a 17% higher compressive force than the polymer itself and interestingly, a 49% higher compressive force than the polymer with randomly dispersed MWNTs, indicating that the orientation of MWNTs in polymer composites affects their curing behavior as well as mechanical strength. These polymer-MWNT composites can be used as-is or coated on other materials and can be expected to exhibit enhanced mechanical properties in various applications.

Evaluation of conductivity and piezo-impedance response of VACNTs/PDMS nanocomposite-based strain sensors under small deformations

The vertically aligned multi-walled carbon nanotubes (VACNTs) / polydimethylsiloxane (PDMS) nanocomposite-based strain sensors presented in this study show different behavior depending on catalyst concentrations for VACNT growth. Under static tensile load, the sensor with lower catalyst concentration shows a high gauge factor (GF~1400), whereupon tunneling effect is the mechanism that dictates the sensitivity. For higher concentrations, the GF decreases (GF~40) and shows an ohmic conduction. Morphological examinations showed VACNTs are homogeneously and randomly distributed as clusters with CNT bridging in the PDMS polymer matrix. Based on dielectric impedance (DI) and direct current (DC) electrical analysis, it was possible to identify that cut-off frequency (fc) increases with VACNTs concentration. Cut-off frequency can also define high sensitivity VACNT sensors with lower VACNT density. When compared with dispersed MWCNT sensors, VACNTs have a reduced fc due to the larger internal resistance variation associated with the high tunneling effect. This effect associated with the high sensitivity of the VACNT/PDMs sensors makes it a key factor to understand the mechanisms responsible for increasing the sensitivity and manufacturing of high GF nanocomposite stretchable sensors.

Lithography-free synthesis of periodic, vertically-aligned, multi-walled carbon nanotube arrays

Until now, the growth of periodic vertically aligned multi-walled carbon nanotube (VA-MWCNT) arrays was dependent on at least one lithography step during fabrication. Here, we demonstrate a lithography-free fabrication method to grow hexagonal arrays of self-standing VA-MWCNTs with tunable pitch and MWCNT size. The MWCNTs are synthesized by plasma enhanced chemical vapor deposition (PECVD) from Ni catalyst particles. Template guided dewetting of a thin Ni film on a hexagonally close-packed silica particle monolayer provides periodically distributed Ni catalyst particles as seeds for the growth of the periodic MWCNT arrays. The diameter of the silica particles directly controls the pitch of the periodic VA-MWCNT arrays from 600 nm to as small as 160 nm. The diameter and length of the individual MWCNTs can also be readily adjusted and are a function of the Ni particle size and PECVD time. This unique method of lithography-free growth of periodic VA-MWCNT arrays can be utilized for the fabrication of large-scale biomimetic materials.

Plasma and Thermal Processing for Designing Hybrid Carbon-Nickel Sulfide Composite Electrodes

There are enormous efforts being made to develop alternative energy storage devices and to meet the energy needs beyond consumer electronics and electric vehicles. Considering batteries and supercapacitors as one of the best performing energy storage devices with high specific energy and power density, there are lots of efforts have been applied to improve the electrochemical features. Amide the different approaches, one of the direct method to improve the performance of such devices are by employing potential electrode materials. Transition metal sulfides are considered as the potential candidates for the next-generation energy storage electrodes. The conversion-reaction induced charge storage mechanism makes them as a promising material for designing high-capacity electrodes for electrochemical energy storage devices. However, poor conductivity and pulverization during the cycling process limits their applications as energy storage devices by limiting the cycle life, capacity and energy density. Thus a combination of metal sulfide phases with hierarchical carbon nanostructures is proposed to address these limitations. Additionally, the direct growth of electrode material on the current collector can overcome the issues related to the binders and internal resistance. In this aspect combining metal sulfides with carbon nanostructures directly grown on current collectors can be used as an advanced electrode material for energy storage applications. Herein, a fast, two-step approach is demonstrated for fabricating a hybrid electrode, consisting of trinickel disulfide (Ni3S2), metallic Ni nanoparticle and vertically aligned multi-walled carbon nanotubes (VCN) in the form Ni3S2/Ni@VCN. The VCN structure is prepared by plasma-assisted techniques, and the nickel sulfide is anchored by the thermal annealing. These Ni3S2/Ni@VCN composites can be directly used as a binder-free electrode for energy storage devices without any further processing, which makes the procedure as a promising technique for the fast fabrication of electrode materials for energy storage devices.

One-step synthesis of highly pure and well-crystallized vertically aligned carbon nanotubes

The one-step aerosol-assisted catalytic chemical vapor deposition (CCVD) process, when operated in a H2-based carrier gas, is shown to be effective at an extremely low ferrocene content (0.1 wt% in toluene), which enables to efficiently prepare forests of vertically aligned multiwalled carbon nanotubes (VACNTs) with high purity and good crystalline level. The resulting iron content in VACNT sample is only 0.5 wt% corresponding to a high catalytic yield of 200 while the steady growth rate (20 μm/min) is maintained at a significant value. The iron content in the sample is found proportional to the ferrocene concentration in the precursor, and when it decreases, a noticeable reduction in the iron encapsulation frequency in the nanotube channel is plainly observed. Lowering the ferrocene concentration generates a reduction in the VACNT number density while the growth rate increases and CNT diameters and crystalline structure remain similar. Such significant purity and crystalline levels involves a high oxidation resistance of the VACNT forest. These results, together with the in-situ continuous growth feature of the one-step aerosol assisted CCVD process, open up towards a new VACNT range made of pure and well-crystallized multi-walled carbon nanotubes, which is of interest for industrial production and commercial applications.

Vertically-Aligned Multi-Walled Carbon Nano Tube Pillars with Various Diameters under Compression: Pristine and NbTiN Coated.

In this paper, the compressive stress of pristine and coated vertically-aligned (VA) multi-walled (MW) carbon nanotube (CNT) pillars were investigated using flat-punch nano-indentation. VA-MWCNT pillars of various diameters (30–150 µm) grown by low-pressure chemical vapor deposition on silicon wafer. A conformal brittle coating of niobium-titanium-nitride with high superconductivity temperature was deposited on the VA-MWCNT pillars using atomic layer deposition. The coating together with the pillars could form a superconductive vertical interconnect. The indentation tests showed foam-like behavior of pristine CNTs and ceramic-like fracture of conformal coated CNTs. The compressive strength and the elastic modulus for pristine CNTs could be divided into three regimes of linear elastic, oscillatory plateau, and exponential densification. The elastic modulus of pristine CNTs increased for a smaller pillar diameter. The response of the coated VA-MWCNTs depended on the diffusion depth of the coating in the pillar and their elastic modulus increased with pillar diameter due to the higher sidewall area. Tuning the material properties by conformal coating on various diameter pillars enhanced the mechanical performance and the vertical interconnect access (via) reliability. The results could be useful for quantum computing applications that require high-density superconducting vertical interconnects and reliable operation at reduced temperatures.

Functionalized, Vertically Super-Aligned Multiwalled Carbon Nanotubes for Potential Biomedical Applications.

Currently, there is a lack of ultrasensitive diagnostic tool to detect some diseases such as ischemic stroke, thereby impacting effective and efficient intervention for such diseases at an embryonic stage. In addition to the lack of proper detection of the neurological diseases, there is also a challenge in the treatment of these diseases. Carbon nanotubes have a potential to be employed in solving the theragnostic challenges in those diseases. In this study, carbon nanotubes were successfully synthesized for potential application in the detection and treatment of the neurological diseases such as ischemic stroke. Vertically aligned multiwalled carbon nanotubes (VA-MWCNTs) were purified with HCl, carboxylated with H2SO4:HNO3 (3:1) and acylated with SOCl2 for use in potential targeting studies and for the design of a carbon-based electrode for possible application in the diagnosis of neurological diseases, including ischemic stroke. MWCNTs were washed, extracted from the filter membranes and dried in a vacuum oven at 60 °C for 24 h prior to functionalization and PEGylation. CNTs were characterized by SEM, TEM, OCA, DLS, CV and EIS. The HCl-treated CNT obtained showed an internal diameter, outer diameter and thickness of 8 nm, 34 nm and 75 µm, while these parameters for the H2SO4-HNO3-treated CNT were 8 nm, 23 nm and 41µm, respectively. PEGylated CNT demonstrated zeta potential, polydispersive index and particle size distribution of 6 mV, 0.41 and 98 nm, respectively. VA-MWCNTs from quartz tube were successfully purified, carboxylated, acylated and PEGylated for potential functionalization for use in targeting studies. For designing the carbon-based electrode, VA-MWCNTs on silicon wafer were successfully incorporated into epoxy resin for diagnostic applications. Functionalized MWCNTs were nontoxic towards PC-12 neuronal cells. In conclusion, vertically super-aligned MWCNTs have been successfully synthesized and functionalized for possible theragnostic biomedical applications in neurological disorders such as ischemic stroke.

Infrared absorbance of vertically-aligned multi-walled CNT forest as a function of synthesis temperature and time

In this paper, the growth of optimized vertically aligned multi-walled carbon nanotube (VA-MWCNT) forests by LPCVD method for use in a large-area absorber in infrared detectors is presented. The effect of synthesis temperature (500−700 °C) and time (1−10 min) on the optical absorption coefficient in the infrared (2−20 μm) is investigated by FT-IR measurement at various incident angles (15-80°). The structural properties of VA-MWCNT are characterized by SEM, TEM and Raman spectroscopy. Spectral measurements show an increasing absorption with the height of the forest that results at increased synthesis time and temperature. However, the absorption coefficient decreases with increasing synthesize time and temperature, while it is also affected by other properties, such as diameter, density, alignment, and uniformity. Moreover, the reduction in absorption at oblique incident angles demonstrates the relevance of surface properties. Finally, a circular graphite waveguide system is used to model the absorption characteristics of an MWCNT forest.

Vertically aligned carbon nanotube micropillars induce unidirectional chondrocyte orientation

Articular cartilage is a highly organized tissue with very limited regenerative capacities. One limitation to mimic cartilage structure in tissue engineering is due to specific orientation of chondrocytes. Here, we use vertically aligned multi-wall carbon nanotubes (VA-MWCNT) micropillars to achieve unidirectional orientation of chondrocytes. We demonstrate that the attachment, proliferation and extracellular matrix (ECM) production by the chondrocytes is enhanced on VA-MWCNT micropillars compared to controls. The nanostructures offered by the VA-MWCNT allow the chondrocytes to anchor at cellular structure level, while mechanical flexibility of the VA-MWCNT micropillars mimics the cartilage’s natural ECM Young’s modulus. We exploit these features to extrapolate the contractile forces exerted by the chondrocytes on the micropillars. Our findings will guide the design of VA-MWCNT templates to model cell’s contractile forces. Furthermore, the capability of VA-MWCNTs to induce unidirectional chondrocytes orientation open new perspectives in cartilage tissue engineering.

Vertically aligned multi-walled carbon nanotubes based flexible immunosensor for extreme low level detection of multidrug resistant leukemia cells

We report an advanced flexible immunosensor for extreme low level detection of multidrug resistant myeloid leukemia cells. The detection mechanism is analyzed in terms of novel nanoscale interactions of target molecules with vertically aligned multi-walled carbon nanotubes (VA-MWNT). The immunosensor is fabricated by transferring VA-MWNTs on a polyethylene terephthalate substrate by hot press technique without losing CNTs’ pristine character. Sensing is performed using doxorubicin treated leukemia K562 cells in varying concentrations from 1.5 × 102 cells mL–1 to 1.5 × 107 cells mL–1 and sensor showed detection limit of 10 cells mL–1. The calibration plot of peak current versus logarithmic concentration of DOX/leukemia K562 cells exhibited good linearity with a regression coefficient of ˜0.98. Sensing mechanism is explained in terms of charge transfer induced Fermi level shift of sub μeV order, causing band bending at the interface of CNT-molecular species; and it is reflected in lowering detection limit of the fabricated sensor. Theoretical analysis is done to correlate Fermi energy shift with sensitivity of the device on cancer cell immobilization. Additionally, the developed immunosensor shows good stability, reproducibility and fast detection vis-à-vis the devices reported so far. The notable advantages of proposed flexible sensor are its durability, chemical and moisture resistance, making it a potentially competitive device for point-of-care diagnostics.

Dexamethasone-Loaded, PEGylated, Vertically Aligned, Multiwalled Carbon Nanotubes for Potential Ischemic Stroke Intervention

The complete synthesis, optimization, purification, functionalization and evaluation of vertically aligned multiwalled carbon nanotubes (VA-MWCNTs) was reported for potential application in dexamethasone delivery to the ischemic brain tissue. The conditions for high yield were optimized and carbon nanotubes functionalized and PEGylated prior to dexamethasone loading. Morphological changes were confirmed by SEM and TEM. Addition of functional groups to MWCNTs was demonstrated by FTIR. Thermal stability reduced following MWCNTs functionalization as demonstrated in TGA. The presence of carbon at 2θ of 25° and iron at 2θ of 45° in MWCNTs was illustrated by XRD. Polydispersive index and zeta potential were found to be 0.261 and −15.0 mV, respectively. Dexamethasone release increased by 55%, 65% and 95% in pH of 7.4, 6.5 and 5.5 respectively as evaluated by UV-VIS. The functionalized VA-MWCNTs were demonstrated to be less toxic in PC-12 cells in the concentration range from 20 to 20,000 µg/mL. These findings have demonstrated the potential of VA-MWCNTs in the enhancement of fast and prolonged release of dexamethasone which could lead to the effective treatment of ischemic stroke. More work is under way for targeting ischemic sites using atrial natriuretic peptide antibody in stroke rats.

Tuning SERS properties of pattern-based MWNTs-AuNPs substrates by adjustment of the pattern spacings

Vertically-aligned multi-walled carbon nanotubes (MWNTs) arrays were designed with different pattern spacings on silicon wafer and tunable three-dimensional (3D) surface-enhanced Raman scattering (SERS) substrates were fabricated by decorating the patterned MWNTs arrays with gold nanoparticles (AuNPs) via magnetron sputtering and annealing. SERS substrates with large amounts of “hot spots” were achieved by adjusting the thickness of sputtered gold film. The microstructure of MWNTs-AuNPs hybrid materials were examined under scanning electron microscopy (SEM) and transmission electron microscope (TEM). The Raman scattering behavior of MWNTs arrays was systematically investigated. Surface-enhanced Raman scattering property of MWNTs-AuNPs was demonstrated using molecular probes Rhodamine 6G (R6G) solutions as standard analyte and the pattern spacing was found to significantly affect Raman intensity. MWNTs-AuNPs substrates with pattern spacing of 100 nm were used to evaluate the SERS property of the material and the detection concentration level was found as low as 10−10 M.

Terahertz emission from vertically aligned multi-wall carbon nanotubes and their composites by optical excitation

Terahertz (THz) emission has been successfully observed from vertically aligned multi-wall carbon nanotube (VAMCNT) materials excited with polarized laser pulse in a reflection configuration. The effects of experimental parameters on THz generation are investigated systematically. The results indicate that the linear dependence of THz electric field on the pump power shows a typical second-order nonlinear optical effect and the transient photocurrent for generating THz waves is mainly originated from photon drag effect. By comparing with THz emission from polymer-coated VAMCNT composites, the detailed generation process of THz waves from VAMCNT materials is clarified: the free carriers in VAMCNT films could transport both along single nanotube and between the adjacent nanotubes, while free carriers in VAMCNT composite films transport mainly along the tube axis due to the isolated carrier transport between the adjacent nanotubes by the coated polymer. Thus, transient photocurrent for generating THz emission from VAMCNT composite films is only along the tube axis and its intensity depends on the component of the pump light electric field along the tube axis. In addition, THz emission from VAMCNT composites shows more regular response than that from pure VAMCNT films, which paves a way for stable performance of VAMCNT-based THz emitter.

Extensive growth of MWCNTs on copper substrates using various diffusion barrier layers

The massive growth of vertically aligned multiwall carbon nanotubes (VA-MWCNTs) on metallic substrates has been a challenge since their early days. In this paper, we demonstrate a way of replacing conventional and expensive crystalline silicon (Si) substrates with cheaper metallic substrates such as Copper (Cu) that are of great interest because of their low cost and high thermal and electrical conductivities for various potential applications. The present work addresses several issues regarding the diffusion of the catalytic particles into the Cu surface at high temperature, which hinders the growth of CNTs through chemical vapor deposition (CVD) process. Different barrier layers such as nickel (Ni), chromium (Cr), and alumina (Al2O3) have been deposited to determine their effectiveness in improving the yield of CNTs growth by stopping this diffusion. The high quality growth of VA-MWCNTs with diameter in 20–60 nm range and the length up to several hundreds of micrometers is achieved on Cu substrates with carpet thickness up to 1 mm using Al2O3 as barrier layer. Moreover, this growth process gives a good reproducibility overcoming an issue which posed a challenge to the scientific community until today. The alignment and the quality of CNTs are characterized by SEM, EDX, TGA, XPS and Raman spectroscopy and results are compared with CNTs grown in similar conditions on Si substrates. CNT grown on Cu, under the similar conditions, have less impurities, better graphitization and lower surface oxidation. The reason for interposing diffusion barrier layer is also discussed in details. This reported progress in the growth may result in a much cheaper VA-MWCNTs production. Moreover, Cu is more suitable as substrate for thermal and various other practical applications of MWCNTs.

Fast mass transport-assisted convective heat transfer through a multi-walled carbon nanotube array.

The recently reported fast mass transport through nanochannels provides a unique opportunity to explore nanoscale energy transport. Here we experimentally investigated the convective heat transport of air through vertically aligned multi-walled carbon nanotubes (VAMWNTs). The flow through the unit cell, defined as an interstitial space among four adjacent nanotubes (hydraulic diameter = 84.9 nm), was in the transition (0.62 ≤ Knudsen number ≤ 0.78) and creeping flow (3.83 × 10-5 ≤ Reynolds number (Re) ≤ 1.55 × 10-4) regime. The constant heat flux (0.102 or 0.286 W m-2) was supplied by a single-mode microwave (2.45 GHz) instantly heating the VAMWNTs. The volume flow rate was two orders of magnitude greater than the Hagen-Poiseuille theory value. The experimentally determined convective heat transfer coefficient (h, 3.70 × 10-4-4.01 × 10-3 W m-2 K-1) and Nusselt number (Nu, 1.17 × 10-9-1.26 × 10-8) were small partly due to the small Re. A further increase in Re (2.12 × 10-3) with the support of a polytetrafluoroethylene mesh significantly increased h (5.48 × 10-2 W m-2 K-1) and Nu (2.37 × 10-7). A large number of nanochannels in a given cross-section of heat sinks may enhance the heat dissipation significantly.

Optical bandgap modelling from the structural arrangement of carbon nanotubes.

The optical bandgap properties of vertically-aligned carbon nanotube (VACNT) arrays were probed through their interaction with white light, with the light reflected from the rotating arrays measured with a spectrometer. The precise deterministic control over the structure of vertically-aligned carbon nanotube arrays through electron beam lithography and well-controlled growth conditions brings with it the ability to produce exotic photonic crystals over a relatively large area. The characterisation of the behaviour of these materials in the presence of light is a necessary first step toward application. Relatively large area array structures of high-quality VACNTs were fabricated in square, hexagonal, circular and pseudorandom patterned arrays with length scales on the order of those of visible light for the purpose of investigating how they may be used to manipulate an impinging light beam. In order to investigate the optical properties of these arrays a set of measurement apparatus was designed which allowed the accurate measurement of their optical bandgap characteristics. The patterned samples were rotated under the illuminating white light beam, revealing interesting optical bandgap results caused by the changing patterns and relative positions of the scattering elements (VACNTs).

Dielectric properties of vertically aligned multi-walled carbon nanotubes in the terahertz and mid-infrared range

We investigate the broadband dielectric properties of vertically aligned, multi-wall carbon nanotubes (VACNT), over both the terahertz (THz) and mid-infrared spectral ranges. The nominally undoped, metallic VACNT samples are probed at normal incidence, i.e. the response is predominantly due to polarisation perpendicular to the CNT axis. A detailed comparison of various conductivity models and previously reported results is presented for the non-Drude behaviour we observe in the conventional THz range (up to 2.5 THz). Extension to the mid-infrared range reveals an absorption peak at , reminiscent of that observed in single-wall CNT, only there it arises for polarisation parallel to the CNT axis. To account for the observed resonance here, we apply a Bergman-type effective-medium theory, based on first-principles’ electromagnetic simulations for the perpendicular polarisation including both the intra- and inter-tube response, which can reproduce the observed spectrum if one assumes a much higher plasma frequency and scattering rate than that reflected in the low-frequency spectra, and proposes an explanation for the non-Drude behaviour at low-frequencies.

Laser-driven coating of vertically aligned carbon nanotubes with manganese oxide from metal organic precursors for energy storage

Carbon nanotubes-transition metal oxide systems are intensively studied due to their excellent properties for electrochemical applications. In this work, an innovative procedure is developed for the synthesis of vertically aligned multi-walled carbon nanotubes (VACNTs) coated with transition metal oxide nanostructures. VACNTs are grown by plasma enhanced chemical vapor deposition and coated with a manganese-based metal organic precursor (MOP) film based on manganese acetate solution. Subsequent UV pulsed laser irradiation induces the effective heating-decomposition of the MOP leading to the crystallization of manganese oxide nanostructures on the VACNT surface. The study of the morphology, structure and composition of the synthesized materials shows the formation of randomly oriented MnO2 crystals, with few nanometers in size, and to their alignment in hundreds of nm long filament-like structures, parallel to the CNT’s long axis. Electrochemical measurements reveal a significant increase of the specific capacitance of the MnO2-VACNT system (100 F g−1) as compared to the initial VACNT one (21 F g−1).

Elastic modulus measurements of vertically aligned multi walled carbon nanotubes carpets by using the nanoindentation technique

Electrical, thermal and mechanical properties of Vertically Aligned Multi Walled Carbon NanoTubes (VA-MWCNT) make them an ideal candidate to replace some of conventional materials in micro and nano-electronic components. Integrating this material in micro components requires a good knowledge of their properties. As the electrical and thermal properties, the MWCNT mechanical properties are difficult to assess. Several techniques have been developed to estimate the CNT Young's modulus and the obtained results cover a large range of scale. In this study, we propose an indirect technique for MWCNT carpet Young's modulus measurements by using the nanoindentation technique. Nanoindentation tests are performed on a metallic film deposited on MWCNT. The measured equivalent reduced modulus takes into account the elastic properties of the metallic thin film and those of the MWCNT substrate. Bec et al. model, introduced in 2006, is used to separate elastic properties, and thus determine the MWCNT reduced Young’s modulus which is estimated between 329 and 352GPa. Knowing the indenter mechanical properties, we estimate the Young’s modulus in the 461 to507GPa range.