"We identify the mechanisms required for mass amplification of nanotubes," said co-lead author Jia Liu, a doctoral student in chemistry at the USC Dornsife College of Letters, Arts and Sciences, recalling the moment when, alone in a dark room, she finally saw the spectral data supporting their method. "It was my Eureka moment."
"To understand nanotube growth behaviors allows us to produce larger amounts of nanotubes and better control that growth," she continued.
Each defined type of carbon nanotube has a frequency at which it expands and contracts. The researchers showed that the newly grown nanotubes had the same atomic structure by matching the Raman frequency.
"This is a very exciting field, and this was the most difficult problem," said co-lead author Bilu Liu, a postdoctoral research associate at the USC Viterbi School of Engineering. "I met Professor Zhou [senior author of the paper] at a conference and he said he wanted to tackle the challenge of controlling the atomic structure of nanotubes. That's what brought me to his lab, because it was the biggest challenge."
In addition, the study found that nanotubes with different structures also behave very differently during their growth, with some nanotube structures growing faster and others growing longer under certain conditions.
"Previously it was very difficult to control the chirality, or atomic structure, of nanotubes, particularly when using metal nanoparticles," Bilu Liu said. "The structures may look quite similar, but the properties are very different. In this paper we decode the atomic structure of nanotubes and show how to control precisely that atomic structure."
|Contact: Suzanne Wu|
University of Southern California