摘要:
A process for the transformation of carbon nanotubes (CNTs) to nanoribbons composed of a few layers of graphene by a two-step electrochemical approach is disclosed in this invention. This consists of the oxidation of CNTs at controlled potential, followed by reduction to form graphene nanoribbons (GNRs) having smooth edges and fewer defects, as evidenced by multiple characterization techni-ques, including Raman spectroscopy, atomic force micro-scopy, and transmission electron microscopy. This type of'unzipping" of CNTs (single-walled, multi- walled) in the presence of an interfacial electric field provides unique advantages with respect to the orientation of CNTs, which might make possible the production of GNRs with con-trolled widths and fewer defects. The extent of oxidation was confirmed by various characterization techniques like XRD, XPS and Raman spectroscopy. In the second step of experiments, the CNT oxide were reduced for different periods such as 4, 8, 12 hours at fixed negative potentials of -0.5 V, so as to get layers of graphene ribbons as tabulated herein.
摘要:
A graphene-reinforced polymer matrix composite comprising an essentially uniform distribution in a thermoplastic polymer of about 10% to about 50% of total composite weight of particles selected from graphite microp articles, single-layer graphene nanoparticles, multilayer graphene nanoparticles, and combinations thereof, where at least 50 wt % of the particles consist of single- and/or multi-layer graphene nanoparticles less than 50 nanometers thick along a c-axis direction. The graphene-reinforced polymer matrix is prepared by a method comprising (a) distributing graphite microparticles into a molten thermoplastic polymer phase comprising one or more matrix polymers; and (b) applying a succession of shear strain events to the molten polymer phase so that the matrix polymers exfoliate the graphite successively with each event until at least 50% of the graphite is exfoliated to form a distribution in the molten polymer phase of single- and multi-layer graphene nanoparticles less than 50 nanometers thick along a c-axis direction.
摘要:
Apparatus and system of components to mechanically exfoliate particulate materials using a multi-axis approach to deliver predetermined forces to a particulate material, including containers to hold particulate material and media, also including media, and, the associated parameters for operating such equipment along with methods and compositions provided by the apparatus and methods.
摘要:
A wiring includes a graphene having a five-seven-membered ring-dense region. The graphene has a plurality of unit cells each including a five-seven-membered ring. The length of the unit cell is 1 nm or more. The shortest distance between most closely adjacent unit cells among the unit cells is 5 nm or less in the five-seven-membered ring-dense region.
摘要:
A graphene-reinforced polymer matrix composite comprising an essentially uniform distribution in a thermoplastic polymer of about 10% to about 50% of total composite weight of particles selected from graphite microp articles, single-layer graphene nanoparticles, multilayer graphene nanoparticles, and combinations thereof, where at least 50 wt % of the particles consist of single- and/or multi-layer graphene nanoparticles less than 50 nanometers thick along a c-axis direction. The graphene-reinforced polymer matrix is prepared by a method comprising (a) distributing graphite microparticles into a molten thermoplastic polymer phase comprising one or more matrix polymers; and (b) applying a succession of shear strain events to the molten polymer phase so that the matrix polymers exfoliate the graphite successively with each event until at least 50% of the graphite is exfoliated to form a distribution in the molten polymer phase of single- and multi-layer graphene nanoparticles less than 50 nanometers thick along a c-axis direction.
摘要:
The invention relates to an electrode (100) for an electrochemical gas sensor (1) wherein the electrode has a gas-permeable membrane, and wherein a graphene layer (3) is deposited on the gas-permeable membrane (4) as electrode material. An electrode (1) of this type is manufactured, for example, in that a dispersion of graphene or graphene oxide in a volatile liquid is applied onto a gas-permeable membrane and the volatile liquid is evaporated.
摘要:
A method of reducing a gaseous carbon oxide includes reacting a carbon oxide with a gaseous reducing agent in the presence of a non-ferrous catalyst. The reaction proceeds under conditions adapted to produce solid carbon of various allotropes and morphologies, the selective formation of which can be controlled by means of controlling reaction gas composition and reaction conditions including temperature and pressure. A method for utilizing a non-ferrous catalyst in a reactor includes placing the catalyst in a suitable reactor and flowing reaction gases comprising a carbon oxide with at least one gaseous reducing agent through the reactor where, in the presence of the catalyst, at least a portion of the carbon in the carbon oxide is converted to solid carbon and a tail gas mixture containing water vapor.