The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
Nitrogen-rich mesoporous carbons were synthesized using an inexpensive and readily available gelatin biopolymer as a carbon/nitrogen precursor and colloidal silica as a hard template. The resulting materials exhibited large pore volumes of up to 4.38cm3/g, bimodal porosity (pores centered at approximately 3 and 24–28nm) and contained high levels of bulk and surface nitrogen (up to 10wt% and 5.8at...
Two-dimensional (2D) layers like graphene are subject to long-wavelength fluctuations that manifest themselves as strong height fluctuations (ripples). In order to control the ripples, their relationship with external strain needs to be established. We therefore perform molecular dynamics (MD) of suspended graphene, by the use of a newly developed force field model (MMP) that we prove to be extremely...
The impurity effects on the dynamics of polarons in armchair graphene nanoribbons are numerically investigated in the scope of a two-dimensional tight-binding approach with lattice relaxation. The results show that the presence of an impurity changes significantly the net charge distribution associated to the polaron structure. Moreover, the interplay between external electric field and the local...
Four three-dimensional graphdiyne polymers, namely Tri-C18, Hex-C36, Tri-C54, and Orth-C72, are predicted with first principles calculations. These carbon allotropes are constituted with interlinked sp3-hybridized carbon pillars and sp2-hybridized graphene-like nanoribbons. Graphdiyne polymers are energetically more stable than C60 and graphdiyne, and show lower phase transition energy barriers from...
Micro/meso-porous reduced graphite oxide (MMRGO) nanosheets were produced using precursor carbide-derived carbon (CDC), which was produced at a high temperature of 1200°C, through a massive wet chemistry synthetic route involving graphite oxidation and microwave reduction. X-ray diffraction (XRD) and transmission electron microscopy (TEM) show that the MMRGO nanosheets were fabricated with 2–3 layers...
A novel architecture of graphene wrapped copper–nickel (Cu–Ni) nanospheres (NSs)/graphene film was proposed to be TCO- and Pt-free counter electrode (CE) with high electrocatalytic activity for dye-sensitized solar cells (DSSCs). The novel architecture CE is composed of highly conductive graphene film, Cu–Ni alloy NSs and the wrapping graphene on the surface of alloy NSs. The graphene film as an electrically...
Coexistence of nonvolatile and volatile resistive switching behaviors was demonstrated in Cu/amorphous carbon/Pt sandwich-structure memory devices by adjusting compliance currents (CCs) to control the size of Cu conductive filament (CF). It was observed that the retention time of the volatile switching strongly depends on the CF’s size, and can be tuned in a wide range from hundreds of milliseconds...
Dispersion remains a technical challenge for effective applications of carbon nanotubes (CNTs). We observed an interesting sorption phenomenon that measured sorption capacity of small and polar aromatic organic molecules (SPAOMs) by CNTs is up to 230 times higher than their theoretically calculated monolayer sorption capacity. Therefore, here we report the dispersion of CNTs using SPAOMs. The stability...
We investigate dynamic fracture of C/SiC composites under high strain-rate compression or tension with split Hopkinson pressure bar (SHPB) and gas gun loading. Components of the as-fabricated composites are mapped and quantified with X-ray computed tomography, including C fibers and fiber bundles, SiC matrix, and inter- and intrabundle voids. Compression loading is applied along the out-of- and in-plane...
A large area carbon nanotube field emission backlight that is built with a new cathode structure is reported. The approach involves unique gate insulator formation by glass etching, highly populated multi wall nanotube tips, and gate electrode assembly by anodic bonding. Impressive lamping performances are noted through dynamic control of the built in fine 4320 local dimming blocks as small as 1cm...
We report sodium dodecyl sulfate (SDS) stabilization of graphene nanosheets, with two different sizes as auxiliary fillers inside the conventional electrically conductive adhesive (ECA) composite. Using this non-covalent modification approach we were able to preserve the single-layer structure of graphene layers and prevent their re-stacking inside the composite, which resulted in a significant electrical...
The effects of the length of single-wall carbon nanotubes (SWCNTs) on their thin film transistors (TFTs) were investigated by using SWCNTs sorted in length using size exclusion chromatography. Higher device performances were obtained in longer SWCNTs and it was found that the average length of the SWCNTs is an important factor to determine the device performance. Detailed analyses, in which the SWCNT...
Graphite is a widely used anode electrode material for Li-ion batteries. When the anode is polarized to a low potential, the electrolyte reduction products form a film called SEI (Solid Electrolyte Interphase) playing a crucial role in the reversibility of the electrochemical cycling. This SEI layer is preferentially formed through the carbon edge planes that can be divided into two main categories...
Ultra-thin single-walled carbon nanotubes (SWCNTs) with a narrow diameter distribution are prepared with a Fe catalyst under an optimized H2/He atmosphere by arc discharge first time. These SWCNTs were enriched with a pH–temperature controlled gel chromatography single-chirality separation process. The separation process uses the electrostatic interaction between the gel and the functional groups...
Knowledge of the pore structure of carbon materials including micropores is crucial for applications such as double layer supercapacitors, gas separation, and other applications requiring high specific surface area materials. High surface area is always associated with fine micropores. The pore size distribution (PSD) of microporous carbons is usually evaluated from nitrogen adsorption isotherms measured...
This article addresses the deployment and characterization of a micro-scale aerosol-jet additive manufacturing technology to print graphene interconnects. A highly concentrated graphene ink with viscosity of 21cP and 3.1mg/ml graphene flakes with the lateral size below 200nm was developed and adopted for this process to make a reliable and repeatable graphene deposition on the treated Si/SiO2 wafers...
Ordered polyacrylonitrile (PAN) interphase structures were formed in solution-cast PAN/carbon nanotube (CNT) composite films by enhancing polymer crystallization conditions and processing parameters for five types of CNTs. All film samples were heat-treated using similar stabilization and carbonization (up to 1100°C) processes. Both the precursor and carbonized materials were characterized by electron...
Molecular dynamics simulations using empirical potentials reveal HOPG graphite’s response to irradiations. Two different methodologies: displacement cascades and Frenkel pair accumulations, probe the primary damage and dose effect, respectively. This work reveals that in HOPG graphite primary knock-on atoms with initial energies less than 40keV do not induce amorphisation by direct impact. Rather,...
The p–n–p double transformation and ultrasensitive–insensitive gas sensing of reduced-graphene-oxide-flake stacked films (rGOFSFs) were controlled by changing the annealing temperature from 100 to 400°C on a sodium silicate substrate, as a result of the competition between the thermal reduction, decomposition, and diffusion of Na, as determined from comprehensive microstructure characterization. The...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.