Move over, silicon. In a breakthrough in the quest for the next generation of computers and materials, researchers at USC have solved a longstanding challenge with carbon nanotubes: how to actually build them with specific, predictable atomic structures.
"We are solving a fundamental problem of the carbon nanotube," said Chongwu Zhou, professor in the Ming Hsieh Department of Electrical Engineering at the USC Viterbi School of Engineering and corresponding author of the study published August 23 in the journal Nano Letters. "To be able to control the atomic structure, or chirality, of nanotubes has basically been our dream, a dream in the nanotube field."
If this is an age built on silicon, then the next one may be built on carbon nanotubes, which have shown promise in everything from optics to energy storage to touch screens. Not only are nanotubes transparent, but this research discovery on how to control the atomic structure of nanotubes will pave the way for computers that are smaller, faster and more energy efficient than those reliant on silicon transistors.
"We are now working on scale up the process," Zhou said. "Our method can revoutionize the field and significantly push forward the real applications of nanotube in many fields."
Until now, scientists were unable to "grow" carbon nanotubes with specific attributes—say metallic rather than semiconducting—instead getting mixed, random batches and then sorting them. The sorting process also shortened the nanotubes significantly, making the material less practical for many applications.
For more than three years, the USC team has been working on the idea of using these short sorted nanotubes as "seeds" to grow longer nanotubes, extending them at high temperatures to get the desired atomic structure.
A paper last year by the same team in Nature Communications outlined the technique, and in the current Nano Letters paper, the researchers report on their latest major success: identifying the "growth recipes" for building carbon nanotubes with specific atomic structures.
"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."
Written By: University of Southern Californiacontinue to source article at phys.org