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Advances in the chemical vapor deposition (CVD) growth of graphene have made this material a very attractive candidate for a number of applications including transparent conductors, electronics, optoeletronics, biomedical devices and energy storage. The CVD method requires transfer of graphene on a desired substrate and this is most commonly accomplished with polymers. The removal of polymer carriers is achieved with organic solvents or thermal treatment which makes this approach inappropriate for application to plastic thin films such as polyethylene terephthalate substrates. An ultraclean graphene transfer method under mild conditions is highly desired. In this article, we report a naphthalene-assisted graphene transfer technique which provides a reliable route to residue-free transfer of graphene to both hard and flexible substrates. The quality of the transferred graphene was characterized with atomic force microscopy, scanning electron microscopy, and Raman spectroscopy. Field effect transistors, based on the naphthalene-transfered graphene, were fabricated and characterized. This work has the potential to broaden the applications of CVD graphene in fields where ultraclean graphene and mild graphene transfer conditions are required.

The vibrational spectrum of saturation-doped insulating Rb6C60 has been measured by inelastic neutron scattering at nonzero momentum transfer in the energy range (5 ÷ 200) meV at 20 K. The two lowest-energy fivefold degenerate Hg modes sharpen substantially in comparison with superconducting K3C60, acquiring comparable widths to those found in pristine C60. This is interpreted as evidence for the importance of these modes in the pairing interaction for superconductivity. We estimate that the radial Hg modes make a substantial contribution to the total electron-phonon coupling strength in the superconducting fullerides.

Chemistry will play an increasingly important role in the realization of graphene applications. The chemical formation of covalent carbon–carbon bonds involving the basal plane carbon atoms offers an alternative approach to the control of the electronic properties of graphene, and potentially allows the generation of insulating and semiconducting regions in graphene wafers. This review summarizes recent progress in the covalent modification of epitaxial graphene and the effect that chemistry has on the electronic and magnetic properties of the material.

We present the results of THz, infrared and magneto-optical measurements performed on graphite nanoplatelet films as a function of temper- ature (4.2-300K) and magnetic field (0-17.5T). An effective medium analysis of the low-energy spectral response indicates that the nanoplatelet material is well described by a Drude function plus two infrared absorption bands. Interestingly, the Drude plasma frequency ( 1675cm 1 ) decreases slowly with temperature, whereas the carrier scattering rate ( 175cm 1 ) is temperature independent. Furthermore, measurements in an applied magnetic field at 4.2K show that a large portion of the Drude spectral weight is transferred to finite frequency features corresponding to various Landau-level transitions. Some of these transition energies scale as p B, as expected for Dirac-like quasi-particles in graphene and observed in other graphene-like materials. Thus, our results are consistent with recent theoretical calculations indicating that the spectrum of multilayer graphene can be decomposed into subsystems effectively identical to monolayer or bilayer graphene.

We report the thermal conductivities of graphite nanoplatelet-epoxy composites prepared by exfoliation of natural graphite flakes of varying lateral sizes. We found that utilization of natural graphite flakes of the optimum lateral dimensions (∼200-400 µm) as a starting material for exfoliation significantly enhanced the thermal conductivity of the composite. In order to understand this enhancement we developed a procedure for evaluation of the particle size distribution of graphite nanoplatelets and correlated the measured distributions with the resulting thermal conductivities. In order to expand the scope of our study we applied our statistical and thermal analysis to commercially available graphite nanoplatelet materials.

We report angular dependent 77Se NMR measurements on the partially quenched, metallic, and magnetic field-induced spin density wave (FISDW) states of (TMTSF)2CIO4. To correlate the NMR data with the FISDW phase diagram, electrical transport was also measured concurrently in some cases. Similar measurements on (TMTSF)2PF6 allow comparison of the behavior of the NMR signal of the spin density wave (SDW) transition with that of the FISDW transition. We present details of the experimental findings including the enhancement behavior, and correlations of the angular dependence of the NMR spectra with the spin-lattice relaxation rate 1/T1. A possible model to describe the behavior of the NMR signal intensity and 1/T1 in terms of a Hebel-Slichter mechanism upon crossing the metal-FISDW transition is presented.

We have demonstrated a NH3, NO2 and water vapour sensor based on poly(m-aminobenzene sulfonic acid) functionalized single-walled carbon nanotube (SWNT–PABS) networks. The SWNT–PABS based sensors were fabricated by simple dispersion of SWNT–PABS on top of pre-fabricated gold electrodes. SWNT–PABS sensors showed excellent sensitivity with ppbv level detection limits (i.e., 100 ppbv for NH3 and 20 ppbv for NO2) at room temperature. The response time was short and the response was totally reversible. The sensitivity could be tuned by adjusting the sensor initial resistance. The sensors were also suitable for monitoring relative humidity in air.