Emerging methods to produce carbon nanotubes, which have potential applications in fields as varied as molecular electronics and performance materials, are generating considerable excitement in the scientific community.
Scientists worldwide are conducting extensive research on these carbon forms, which are excellent conductors and provide useful strength and electrical properties.
Commonly produced through methods such as arc discharge, laser ablation, or chemical vapour deposition, nanotubes can also be produced by ball milling, hydrothermal pressure, decomposition of buckyballs, and annealing of soot. However, obtaining large enough quantities of the material continues to be one of the biggest challenges facing nanotechnology researchers.
“To realize their full potential, carbon nanotubes need to be available inexpensively and abundantly,” says Technical Insights Analyst Aninditta Savitry.
Nanotube manufacturing typically produces only 10 mg of nanotubes, but a newly developed approach promises to form trillions within an hour. This method, which involves striking a metal-impregnated carbon target with free-electron laser light, promises to reduce the production cost of nanotubes to $100 per gram from that of $200 per gram using other methods.
“Less expensive nanotubes will enable a wider range of possible applications,” notes Savitry. “Bringing down production costs is an immediate challenge that needs to be addressed.”
Many nanotube production methods exist. One method involves sprouting nanotubes from particulate seeds of an iron and molybdenum catalyst. The process takes place in a chemical vapour deposition chamber where heat and catalysts decompose hydrocarbons.
Some scientists are searching for even more suitable catalysts for growing nanotubes. High-throughput experimentation, for example, holds promise in the pursuit of the most practical catalyst for producing nanotubes with specific properties.
Carbon nanotubes are expected to have a strong impact on our day-to-day life once they are available in large amounts and properly functionalized. Scientists and engineers will then be able to work on getting these useful materials into practical working systems.
“We’ve already seen some significant developments, not only in the electronics sector, but also in the materials, medical, and biotechnology sectors," says Savitry. “Nanotubes may one day be used to create biosensors or enhance the toughness of ceramics."