Large-Scale Synthesis of Perpendicularly Aligned Helical Carbon Nanotubes

Abstract

Large-scale perpendicularly aligned helical carbon nanotube arrays were prepared by co-pyrolysis of Fe(CO)5 and pyridine onto the pristine quartz glass plates in a tube furnace at 900-1100 degrees C under a mixture flow of Ar and H2. The resultant aligned helical carbon nanotubes could not only facilitate the structure-property characterization for helical carbon nanotubes but also allow them to be effectively incorporated into devices for practical applications.

Origin of periodic rippling during chemical vapor deposition growth of carbon nanotube forests

“…The rippling is characterized by smooth consistent curves without any sharp kinks or bends. For any given nanotube, the rippling occurs in a plane, thus they are not helixes such as those observed in other systems [29]. The ripples generally encircle the entire forest (Fig.…”

Carbon nanotubes and helical carbon nanofibers grown by chemical vapour deposition on C60 fullerene supported Pd nanoparticles

“…Reducing pressure Co particles [14]. Also the co-pyrolysis of pyridine and Fe(CO) 5 as floating catalyst showed excellent result [15] and could even lead to vertically aligned helical carbon nanotubes (VAHCNTs) [16]. Sulfur has been shown to play a key role in enabling different catalyst, that under normal conditions are used for the growth of straight structures, to grow helical structures [11,17].…”

Superelastic and Spring Properties of Si3N4 Microcoils

“…[2,3] Various morphologies of Si 3 N 4 in the nano-or micrometer scale [4][5][6][7][8][9] have been explored in the last few years because of their potentials in applications where mechanical strength and high temperature/corrosive durability are required. Compared with other configurations, such as wires, tubes and belts, helical springs observed in a number of inorganic materials [10][11][12][13][14][15][16][17][18][19][20] are expected to have remarkable properties in some aspects. For example, helical spring structures having dimensions on the order of nano-or micrometers are expected to have remarkable mechanical properties due to their helicity and periodicity or as a novel reinforcement in high strain composites.…”