Highly individual single-walled carbon nanotubes synthesized by floating catalyst chemical vapor deposition for transparent conducting films

The bundle formation of single-walled carbon nanotubes (SWCNTs) has dramatically hindered their performances of transparent conducting films (TCFs). Herein, we synthesized less bundled SWCNTs by reducing the concentration of catalyst precursor in floating catalyst chemical vapor deposition. The gas-phase number concentration of SWCNTs could be reduced from 1.6×10⁶ to 4×10⁵ cm⁻³ by decreasing the catalyst precursor and thus, the bundle formation due to nanotube collisions induced by Brownian diffusion was significantly inhibited. ∼42% of SWCNTs were found to be individual with a mean tube diameter of 1.0 nm, mean length of 2.5 μm and mean bundle diameter of 2.1 nm, the corresponding SWCNT TCF exhibited a sheet resistance of 109 Ω/sq. at 90% optical transmittance. Our work provides a strategy of synthesizing highly individual SWCNTs for enhanced performance of TCFs, implying great potential in electronic applications.