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In this paper, we present a novel method for graphene nanoribbons formation using nickel nanowires as templates. Modification of electrochemical procedure for nickel nanowires synthesis was introduced by implementing graphene quantum dots as a carbon source. Thus, nickel nanowires with graphene quantum dots were prepared. These wires were exposed to rapid thermal annealing at high temperatures (500 degrees C, 700 degrees C and 800 degrees C). During this process carbon atoms dissolve in metal and precipitate to the nickel surface forming nickel-carbon nanowires. Atomic force microscopy, scanning electron microscopy and Raman spectroscopy were characterization methods used for analysis of changes in nickel-carbon nanowires properties depending on the different annealing temperatures. After etching nickel with nitric acid, graphene nanoribbons with average diameters of 32 nm and average lengths of 4 mu m were obtained. (C) 2016 Elsevier B.V. All rights reserved.

In this paper, we performed synthesis of graphene thin films by rapid thermal annealing (RTA) of thin nickel copper (Ni/Cu) layers deposited on spectroscopic graphite as a carbon source. Furthermore, we investigated the effect of annealing temperature and annealing time on formation and quality of synthesized graphene films. Raman spectroscopy study showed that annealing at lower temperatures results in formation of monolayer graphene films, while annealing at higher temperatures results in formation of multilayer graphene films. We used Raman mapping to determine the distribution of graphene sheets. Surface morphology of graphene thin films was investigated by atomic force microscopy and scanning electron microscopy with EDS probe.

Enhanced conductivity, transparency and stability are the most important factors to consider in order to prepare electrodes for optoelectronic devices. In this paper, we investigated the properties of poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films doped with graphene and graphene quantum dots. Samples were deposited by spin-coating onto glass substrates. Thin films were characterized by UV-vis and Raman spectroscopy, atomic force microscopy (AFM), scanning electron microscopy (SEM) and four-point probe measurements. It was found that both graphene and graphene quantum dots improve the conductivity of PEDOT:PSS films with only small decrease in transparency. AFM and SEM analysis showed homogenous distribution of spherical nanoparticles of graphene quantum dots and irregular shaped nanoparticles of graphene in PEDOT:PSS.

In this paper we report fabrication and characterization of highly conductive carbon cryogel. The carbon cryogels were prepared by the sol-gel polymerization of resorcinol and formaldehyde in an aqueous surfactant stabilized suspension of graphene. Cryogels with varying graphene loading were fabricated and characterized by four-probe method, scanning electron microscopy, Raman and FTIR spectroscopy, XRD and nitrogen porosimetry. Several properties of carbon cryogels were highly dependent on small change of graphene loading. Carbon cryogel with smaller graphene loading has superior electrical conductivity of 133 S/m. Pore radius varies between 1.5 and 10 nm which means that samples are micro- and mesoporous. Significant transfer of charge to graphene layers was observed by Raman spectroscopy. (C) 2012 Elsevier B.V. All rights reserved.