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Suspended graphene flakes are exposed simultaneously to fluorine and sulfur ions produced by the μ-wave plasma discharge of the SF 6 precursor gas. The microscopic and spectroscopic analyses, performed by Raman spectroscopy, scanning electron microscopy and photoelectron spectromicroscopy, show the homogeneity in functionalization yield over the graphene flakes with F and S atoms covalently bonded to the carbon lattice. This promising surface shows potential for several applications ranging from biomolecule immobilization to lithium battery and hydrogen storage devices. The present co-doping process is an optimal strategy to engineer the graphene surface with a concurrent hydrophobic character, thanks to the fluorine atoms, and a high affinity with metal nanoparticles due to the presence of sulfur atoms. [ABSTRACT FROM AUTHOR]

The chemical modification of Multi-Walled Carbon Nanotubes (MWCNTs) with a long chain mercapto- acid is reported as a way to improve sensitivity and response time of gas sensors for detecting alcohols, acetone and toxic gases such as DMMP. We have developed sensors employing MWCNTs decorated with gold nanoparticles and modified with a monolayer of 16-mercaptohexadecanoic acid (MHDA). Morphological and compositional analysis by Transmission Electron Microscopy (TEM), Fourier Transform Infra-red Spectroscopy (FTIR) and X-ray photoelectron spectroscopy were performed to characterize the gold nanoparticles and to check the bonding of the thiol monolayer. The detection of aromatic and non-aromatic volatiles vapors by MWCNT/Au and MWCNT/Au/MHDA shows that the presence of the self-assembled layer increases sensitivity, selectivity and ameliorates response dynamics of the sensors. [ABSTRACT FROM AUTHOR]