Nanotube brush

Bando and co-workers271 have prepared BN nanolubes by the reaction of MgO, FeO and B in the presence of NH, at 1400 °C. Reaction of boric acid or B20, with N2 or NH, at high temperatures in the presence of carbon or catalytic metal particles has been employed in the preparation of BN nanotubes.2 2 Boron nitride nanotubes can be grown directly on substrates at 873 K by a plasma-enhanced laser-deposition technique.172 Recently, GaN nanotube brushes have been prepared using amorphous carbon nanotubes templates obtained using AAO membranes.274... 

A mixture of boric acid (1 g) and urea (11.8 g) was taken in 40 ml distilled water and heated at 70 °C until the solution became viscous the a-CNTs were soaked in it for nearly 2 h. They were later separated physically and dried in air at 40 C overnight. The dried sample was thermally treated at 970 °C for 3 h for 40 nm nanotubes in a N2 atmosphere, and for 12 h in the case of the larger diameter (170 nm) nanotubes, and then cooled down to room temperature. The product was subsequently heated in an NHt atmosphere at 1050 °C in case of 170 nm nanotubes and 900 C in case of 40 nm nanotubes for three hours to give black-coloured boron-carbon-nitride nanotube brushes. The products were investigated by transmission electron microscopy and other physical techniques. 

In order to obtain Au/Pt nanoparticle-covered BCN nanotube brushes, the nanotubes obtained by the template method described earlier were soaked in 2 mL of 5 mM aqueous solutions of hydrogen hexachloroplatinatc (rv) or hydrogen tetrachloroaurate (III) for 12 h. The nanotubes were washed with distilled water twice followed by a washing with 10 mM sodium borohydride solution before drying at 40 °C for an hour. The resulting products were examined by electron microscopy. 

Fig. 7 Adsorption-desorption isotherms of (a) N2 at 77 K (inset shows the pore size distribution), (b) C02 at 195 K and (c) i F at 77 K for HC..N nanotube brushes.

Fig, 1 (a) SEM image of amorphous carbon nanotube brushes, (b) TEM image of individual amorphous carbon nanotubes. 

Pushparaj, V., et al. (2012). Deformaticn and Capillary Self-Repair of Carbon Nanotube Brushes. Carbon, 50(15), 5618-5620. 

Applying our experience in three-dimensional, selective carbon nanotube growth techniques, we have constructed multifunctional conductive brushes with carbon nanotube bristles grafted on fiber handles, and demonstrated their several unique tasks such as cleaning of nanoparticles from narrow spaces, coating of the inside of holes, selective chemical adsorption, and as movable electromechanical brush contacts and switches [49], The nanotube brush consists of a silicon carbide fiber as the handle and aligned multiwalled carbon nanombes grafted on the fiber ends as bristles. 

In the CVD process to produce multifunctional nanotube brushes, the continuous version of the above-mentioned CVD process was applied a solution made by dissolving 0.3 g ferrocene into 30 ml xylene was injected into the furnace at a constant speed (0.5 ml min ). Argon was flowed to carry the solution into a preheated steel bottle (180°C) before entering the furnace. SiC fibers were placed into the middle of the furnace in an alumina boat. The typical reaction temperature was 800°C, and the growth time took 10 minutes to 1 hour. 

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