Design novel catalysts to control the chirality of single walled carbon nanotubes
Single walled carbon nanotubes (SWCNTs) are hollow carbon cylinders rolled up from one layer of graphene sheet. Depending on the rolling direction of the graphene sheet, SWCNTs have different chirality, which lead to their unique electronic and optical properties. SWCNTs can be either metallic or semiconducting with different band gaps. Due to their ultrathin body of ~1 nm in diameter, ballistic transport properties, and intrinsic band gaps, SWCNT based electronic transistors are considered as a potential disruptive force in the electronics industry. As SWCNTs can emit and detect electromagnetic energy in narrow wavelength windows, they are building blocks for new generation of optoelectronic devices. However, SWCNTs synthesized from all existing methods have a wide distribution of diameter and chirality. This structure-property diversity is a major hurdle in their applications. In the prevailing synthesis method (catalytic chemical vapour deposition), gaseous carbon precursor is catalytically converted into a solid nanotube at the surface of reactive catalysts. Previous experimental studies show that high-chiral-angle small diameter SWCNTs can be obtained using chiral selective catalysts. However, the origin of this selectivity is unclear. A number of mechanisms were proposed, but experimental evidences still could not provide a solid and convincing conclusion. It is fundamentally intriguing to better understand the chirality selectivity in SWCNT growth for developing novel methods to tailor chirality selectivity.
The opportunity ID for this research opportunity is 2029