By combining carbon nanotubes and graphene, Fujitsu Laboratories Ltd. has created a new nanoscale carbon composite featuring a self-organizing structure that can be synthesized at lower temperatures than conventional graphene. Self-organizing means the structure self-forms naturally, without the need for complex controls. The composite can be made at 510°C, paving the way for use in applications in electronic devices that are vulnerable to heat. Fujitsu is presenting details of the technology at the 34th Fullerene Nanotubes General Symposium in Nagoya, Japan.
Carbon nanotubes and graphene are both nanoscale structures consisting of carbon atoms. Graphene is a sheet-like hexagonal lattice of carbon atoms, while nanotubes can be described as graphene wrapped into a cylinder with a nanoscale diameter. Despite the fact that both are made from the same carbon atoms, each has very distinct characteristics. Carbon nanotubes feature the highest thermal conductivity and mechanical strength of any material found in nature, as well as the ability to withstand the highest current density, making them an attractive material for wiring, heat dissipation, field electron emitters, and other potential applications.
Since the discovery of its high electron mobility in 2004, graphene has become attractive as a channel material for future transistors. However, conventional methods for synthesizing graphene only work at temperatures over 700°C—too high for use in electronic devices—or involve a time-consuming and unreliable process of stripping away graphite crystals. Research and development is underway to find technologies to synthesize carbon nanotubes at temperatures as low as approximately 400°C.