Engineering On The Edge

Nanotube defects can heal quickly before they get into the tube wall, according to new research. Image: Rice University

Researchers at Rice University, Hong Kong Polytechnic, and Tsinghua University claim that it is theoretically possible to grow perfect, single-walled carbon nanotubes (thinner than a human hair) up to a meter long over a period of 11.5 days.

The team published its report in the journal Physical Review Letters.

That type of growth would be enabled by the nanotubes’ kinetic self-healing mechanism during catalytic growth. According to the team:

“Our study indicates that, with the assistance of a metal catalyst, TDs formed during the addition of C atoms can be efficiently healed at the CNT-catalyst interface. Theoretically, a TD-free CNT wall with 10^8–10^11 carbon atoms is achievable, and, as a consequence, the growth of perfect CNTs up to 0.1–100 cm long is possible since the linear density of a CNT is about 100 carbon atoms per nanometer.”

This process would help find and fix errors and defects that occur during nanotube production before they became part of the nanotube wall. The researchers identified iron as the best and fastest catalyst, and that the slower the growth, the longer the nanotube could be. According to the research, those longer nanotubes such could be woven into long cables and used for power distribution over the “grid of the future.” They could also play a role in developing cables for a certain space elevator we’ve previously discussed.

Source: Rice University