Characterization of graphene grown by direct-liquid-injection chemical vapor deposition with cyclohexane precursor in N2 ambient

We synthesize graphene films by direct-liquid-injection chemical vapor deposition (DLI-CVD) method with cyclohexane precursor (C6H12) in N2 ambient. This process offers a safer, and more economical route for large-scale graphene production in which hydrogen gas is not required. Graphene films are grown on Cu foil substrates at 890 to 980 °C for 10 min in the total pressure of 2 mbar. The flow rate of cyclohexane is varied between 0.2 and 0.5 g/min. The Raman results shows continuous monolayer graphene films at growth temperature of 950 °C and a flow rate of 0.5 g/min. Hall and field-effect measurements show mobilities in the range of 450–800 cm2 /V·s. The relatively low D peak intensity suggests that carrier mobility is likely limited by impurities introduced to the devices during transfer process and device fabrication.Fil: Intaro, T.. Chulalongkorn University; TailandiaFil: Hodak, Jose Hector. Chulalongkorn University; Tailandia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Suwanyangyaun, P.. Chulalongkorn University; TailandiaFil: Botta, Raju. Thailand National Electronics And Computer Technology Center; TailandiaFil: Nuntawong, N.. Thailand National Electronics And Computer Technology Center; TailandiaFil: Niki, Masaya. Aoyama Gakuin University; JapónFil: Kosuga, S.. Aoyama Gakuin University; JapónFil: Watanabe, T.. Aoyama Gakuin University; JapónFil: Koh, S.. Aoyama Gakuin University; JapónFil: Taychatanapat, T.. Chulalongkorn University; TailandiaFil: Sanorpim, S.. Chulalongkorn University; Tailandi

Hybrids of carbon nanotube forests and gold nanoparticles for improved surface plasmon manipulation

We report the fabrication and characterization of hybrids of vertically-aligned carbon nanotube forests and gold nanoparticles for improved manipulation of their plasmonic properties. Raman spectroscopy of nanotube forests performed at the separation area of nanotube-nanoparticles shows a scattering enhancement factor of the order of 1 × 106. The enhancement is related to the plasmonic coupling of the nanoparticles and is potentially applicable in high-resolution scanning near-field optical microscopy, plasmonics, and photovoltaics. © 2014 American Chemical Society