Iodine-aided fabrication of hollow carbon fibers from solid poly(vinyl alcohol) fibers

✍ Scribed by Ummul Khair Fatema; Chiemi Tomizawa; Masaru Harada; Yasuo Gotoh

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 573 KB
• Volume: 49
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/j.carbon.2011.01.048

✦ Synopsis

of iron. So, the size and the composition of each active catalytic growth site are the same, giving rise to CNTs of the same diameters. Quantitative analysis indicates that 80 g of CNTs can be achieved when 100 g of natural black jew's-ear fungus are used as catalysts. The iron content of natural organic precursors is closely related with the diameter of CNTs. Higher content of Fe is responsible for large sizes of CNTs, whereas lower content of Fe leads to small sizes of CNTs. As to black sesame seeds, the iron content is 0.05%, the diameter of the obtained CNTs is 100 nm. As for black jew's-ear fungus, the iron content is 0.03%, the diameter of the achieved CNTs is 80 nm.

In conclusion, each catalyst particle arises from Fe content of a single cell of the precursor, hence the distribution of catalyst particles is uniform and their size and composition are almost identical. CNT arrays can grow by CVD when black sesame seeds are used as catalyst precursors. The diameter (about 100 nm) is uniform. When natural black jew's-ear fungus are used as catalyst precursors, CNTs can be produced through CVD at 800 °C in a relatively high yield. The diameter is 80 nm and the length is over 100 lm. CNTs are uniformly distributed and no amorphous carbon is produced. This is encouraging for future industrial applications.