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Interfacial shear strength of reduced graphene oxide polymer composites
Interfacial shear strength (IFSS) between particle and matrix in particulate polymer composites is a critical property in determining the mechanical behaviors since it is directly related to not only their Young’s modulus or specific strength, but also energy absorbing capability. However, the conventional techniques often present a technical challenge to accurately measure the IFSS between f...


Carbon nanotube-gelatin-hydroxyapatite nanohybrids with multilayer core–shell structure for mimicking natural bone
We attempted to mimic collagen fibrils bearing apatite crystals in natural bone, using gelatin, carboxylic acid functionalized carbon nanotubes (f-CNTs), and hydroxyapatite (HA). Gelatin molecules were covalently grafted on the surface of f-CNTs by the formation of amide linkages. HA crystals were then assembled onto the gelatin-grafted f-CNTs in a highly concentrated CaP solution, resulting a ...
Improved strength and toughness of polyketone composites using extremely small amount of polyamide 6 grafted graphene oxides
Polyketone (PK) composites were prepared by a solution casting method using 1,1,1,3,3,3-hexafluoro-2-propanol as a solvent and polyamide 6 grafted graphene oxides (PA 6-GOs) as filler materials. PA 6-GOs were obtained by in situ polymerization of ε-caprolactam using GOs having different amounts of oxygen functional groups. The PK composites containing only an extremely small amount of the PA 6...


Thermal transport for flexural and in-plane phonons in graphene nanoribbons
The thermal transport properties of graphene nanoribbons with cavities are studied by non-equilibrium Green’s function approach. A comparative analysis between in-plane and out-of-plane modes is made. The results show that the quantized thermal-conductance plateau of in-plane modes is wider and not broken in graphene nanoribbon with cavities. Contribution of the out-of-plane modes to the tota...
Thermal transport in monolayer graphene oxide: Atomistic insights into phonon engineering through surface chemistry
Thermal transport in monolayer graphene oxide (GO) with randomized surface epoxy and hydroxyl groups, at various degrees of oxidation (O:C ratio), is investigated using non-equilibrium molecular dynamics simulations. We find that the in-plane thermal conductivity of finite sized pristine graphene or GO (5–50nm in simulation) increases with length due to reduced phonon-boundary scattering. The...


Effect of hydrogen flow during cooling phase to achieve uniform and repeatable growth of bilayer graphene on copper foils over large area
The growth of single-layer graphene on copper foil by chemical vapor deposition (CVD) method has been investigated extensively by several groups, however, achieving the same for the bilayer graphene, using a fast and reproducible process, is proven to be difficult and most of the efforts in this direction so far have been on controlling the nucleation phase during active growth regime. In this ...
On the stability of conventional and nano-structured carbon-based catalysts in the oxidative dehydrogenation of ethylbenzene under industrially relevant conditions
Relevant carbon-based materials, home-made carbon–silica hybrids, commercial activated carbon, and nanostructured multi-walled carbon nanotubes (MWCNT) were tested in the oxidative dehydrogenation of ethylbenzene (EB). Special attention was given to the reaction conditions, using a relatively concentrated EB feed (10vol.% EB), and limited excess of O2 (O2:EB=0.6) in order to work at full oxyg...

Nitrogen ion casting on vertically aligned carbon nanotubes: Tip and sidewall chemical modification
Nitrogen inclusion in vertically aligned carbon nanotubes (v-CNTs) was performed in situ and in ultra-high vacuum by nitrogen ion implantation and evaluated by X-ray photoelectron spectromicroscopy. The creation of defects induced by the ions drives the formation of different nitrogen species (pyridinic, pyrrolic, and graphitic) at the CNT surface. While nitrogen implantation in CNT sidewalls h...
Characterization of the effects of 3-MeV proton irradiation on fine-grained isotropic nuclear graphite
The irradiation-induced damage on the fine-grained isotropic nuclear graphite, IG-110, was investigated by 3-MeV proton irradiation at room temperature. The irradiation effects were characterized using scanning electron microscopy, transmission electron microscopy (TEM), Raman spectroscopy, X-ray diffraction (XRD), and nano-indentation. The surface morphology showed a fragmented shape after irr...

Adhesion and differentiation of human mesenchymal stem cells on plasma-functionalized graphenes with different feeding gases
Surface functionalisation of graphene layer has been investigated to improve the efficiencies in bio-applications such as stem cell differentiation or protein sensing. Plasma treatment can induce various functionalities on graphene surface simply by changing feeding gas. In this study, the surface chemistry of graphene is modified by plasma treatment using three different feeding gases of H2, N...
Graphene oxide functionalized with ethylenediamine triacetic acid for heavy metal adsorption and anti-microbial applications
The development of functionalized nanomaterials that leads to multi-functionality, such as the ability to adsorb heavy metals coupled with anti-microbial properties is very attractive for diverse applications. The present study evaluated for the first time the antimicrobial activity of graphene oxide silanized with N-(trimethoxysilylpropyl) ethylenediamine triacetic acid (GO–EDTA) against Gra...

Phonon transport in helically coiled carbon nanotubes
We perform theoretical studies on the phonon thermal transport in helically coiled carbon nanotubes (HCCNTs). The Grüneisen parameter, as a function of the phonon wave vector and phonon branch, is numerically evaluated for each vibrational mode, so that the three-phonon Umklapp scattering rates can be calculated exactly by taking into account all allowed phonon relaxation channels. We consider...
Preparation and lithium-storage performance of carbon/silica composite with a unique porous bicontinuous nanostructure
A class of carbon/silica composite with a porous bicontinuous nanostructure is prepared via a simple sol–gel method and then used as anode material for lithium-ion batteries. The reversible specific capacity of the as-prepared composite stays over 560mAhg−1 after 30 cycles, much higher than that of many other carbon materials including commercial graphite and carbon/silica composites. The g...
Thermal performance of vertically-aligned multi-walled carbon nanotube array grown on platinum film
Vertically-aligned carbon nanotube array is expected to inherit high thermal conductivity and mechanical compliance of individual carbon nanotube and serve as thermal interface material. In this paper, vertically-aligned multi-walled carbon nanotube arrays have been directly grown on Pt film and the thermal performance has been studied by using laser flash technique. The determined thermal diff...
Flipping nanoscale ripples of free-standing graphene using a scanning tunneling microscope tip
We present a scanning tunneling microscopy study of the stress–strain behavior of a rippled single-layer free-standing graphene (FSG) and report that FSG exhibits a non-linear sigmoidal stress–strain behavior. We managed to pull and push nanoripples by controlling the STM tip–FSG interaction forces. In this way, we found that the initial deformations of a rippled FSG involve sign reversal...