Gold nanoparticles were selectively attached to chemically functionalized surface sites on nitrogen-doped carbon (CN x ) nanotubes. A cationic polyelectrolyte was adsorbed on the surface of the nanotubes by electrostatic interaction between carboxyl groups on the chemically oxidized nanotube surface and polyelectrolyte chains. Negatively charged 10 nm gold nanoparticles from a gold colloid suspension were subsequently anchored to the surface of the nanotubes through the electrostatic interaction between the polyelectrolyte and the nanoparticles. This approach provides an efficient method to attach other nanostructures to carbon nanotubes and can be used as an illustrative detection of the functional groups on carbon nanotube surfaces.

No abstract

No abstract

methanol produced from the hydrolysis of the TMOS was slowly removed using a diaphragm vacuum pump (DIVAC 1.2 L) connected to a rotary evaporator at ambient temperature to avoid the destruction of the liquid-crystalline order [20,22]. Within about 5 min, the resulting viscous liquid changed to a translucent, gel-like substance and acquired the desired shape and size of the reaction vessel (Fig. 1). The translucent glassy monoliths were collected and dried at 40 C for 16 h. The surfactant and the incorporated alkanes were removed by calcination at 450 C (3 h under nitrogen and then 14 h under oxygen).XRD patterns were measured using a MXP 18 diffractometer (Mac Science Co. Ltd.) with Cu Ka radiation. The N 2 isothermal data were collected with a Shimadzu ASAP 2020 surface area analyzer. All samples were outgassed at 300 C for 8 h before the N 2 adsorption analyses. The TEM micrographs were obtained with a JEOL JEM-2000 FXII Apparatus operating at an acceleration voltage of 200 kV. SEM micrographs were also obtained with a Hitachi S-800 SEM operated at 7 kV.