Search results for "NANOTUBES"

Mismatch strain versus dangling bonds: formation of "coin-roll nanowires" by stacking nanosheets.

2010

VS2 nanotubes containing organic-amine templates from the NT-VOx precursors and reversible copper intercalation in NT-VS2.

2004

Tunable invisibility cloaking by using isolated graphene-coated nanowires and dimers

2017

AbstractWe investigate, both theoretically and numerically, a graphene-coated nano-cylinder illuminated by a plane electromagnetic wave in the far-infrared range of frequencies. We have derived an analytical formula that enables fast evaluation of the spectral window with a substantial reduction in scattering efficiency for a sufficiently thin cylinder. This polarization-dependent effect leads to tunable resonant invisibility that can be achieved via modification of graphene chemical potential monitored by the gate voltage. A multi-frequency cloaking mechanism based on dimer coated nanowires is also discussed in detail.

One-pot synthesis of ZnO nanoparticles supported on halloysite nanotubes for catalytic applications

2020

Abstract A versatile catalyst based on halloysite and zinc oxide (HNT@ZnO) was prepared, for the first time, starting from ZnO commercial bulk form as Zn precursor source, in a one-pot procedure. This strategy gives the possibility to obtain small ZnO nanoparticles loaded on the HNT surface without the use of inorganic salts which envisage the removal of undesired anions and therefore a calcination process at high temperature. It was found that the presence of halloysite improved the UV–vis spectral absorption ability of ZnO. The hybrid was successful used as photocatalyst for the methylorange and rhodamine B degradation. In addition, after eight consecutive cycles for the methylorange phot…

Hybrid and 2D nanomaterials

2020

International audience; In order to still improve the performances of chemical sensors, numerous hybrid materials were synthesized that combined at least two types of materials reported in the three previous chapters. We will distinguish materials combining macrocyclic molecules with polymers, those in which these molecules are associated to carbonaceous materials, mainly carbon nanotubes (CNTs) and graphene, and organic-inorganic hybrid materials. In this chapter, we will also include 2D materials introduced recently as sensing materials after the huge development of graphene and graphene oxide-based materials.

Surface plasmon effects on carbon nanotube field effect transistors

2011

Herein, we experimentally demonstrate surface plasmon polariton (SPP) induced changes in the conductivity of a carbon nanotube field effect transistor (CNT FET). SPP excitation is done via Kretschmann configuration while the measured CNT FET is situated on the opposite side of the metal layer away from the laser, but within reach of the launched SPPs. We observe a shift of 0.4 V in effective gate voltage. SPP-intermediated desorption of physisorbed oxygen from the device is discussed as a likely explanation of the observed effect. This effect is visible even at low SPP intensities and within a near-infrared range. peerReviewed

The Engineering of Hot Carbon Nanotubes with a Focused Electron Beam

2004

Single-wall and multiwall carbon nanotubes at high temperature are irradiated with the focused electron beam in an electron microscope. Nanotubes can be tailored with monolayer precision, and new morphologies of nanotubes are created. Atoms from layers of multiwall tubes can be removed and the tubes can be bent by a predefined angle. Bundles of single-wall tubes are transformed locally to multiwall tubes with coherent transition between the two modifications.

Second-harmonic Generation Microscopy of Carbon Nanotubes

2012

We image an individual single-walled carbon nanotube (SWNT) by second-harmonic generation (SHG) and transmission electron microscopy and propose that SHG microscopy could be used to probe the handedness of chiral SWNTs.

Advanced ultra-high molecular weight polyethylene/antioxidant-functionalized carbon nanotubes nanocomposites with improved thermo-oxidative resistance

2015

Multiwalled carbon nanotubes (CNTs) functionalized with hindered phenol moieties are dispersed in ultra-high molecular weight polyethylene (UHMWPE), and the stabilizing action of the antioxidant (AO) functionalized CNTs (AO-f-CNTs) is studied through a combination of rheological and spectroscopic (FT-IR) analyses. The effectiveness of two alternative compounding methods, namely hot compaction (HC) and melt mixing (MM), is compared. The combination of high temperature and mechanical stress experienced during MM brings about noticeable degradation phenomena of the matrix already in the course of the compounding step. Differently, the milder conditions of the HC process preserve the stability …

Mechanical and rheological properties of polystyrene-block-polybutadiene-block-polystyrene copolymer reinforced with carbon nanotubes: effect of proc…

2017

Abstract Styrene-b-butadiene-b-styrene (SBS)-based nanocomposites filled with unmodified and –COOH functionalized carbon nanotubes (CNTs) have been formulated at different processing conditions in order to provide an understanding of the influence of the processing temperature and mixing speed on the nanofillers dispersion and on the overall properties of the nanocomposites. The evaluation of the nanocomposites’ mechanical and rheological behavior reveals that the effect of the processing speed on the final properties is almost negligible. Differently, the processing temperature influences strongly the mechanical and rheological properties of SBS-based nanocomposites. Indeed, for the nanoco…