  Single-walled carbon nanotube (SWCNT) films are promising materials for
transparent conductive films (TCFs) with potential applications in flexible
displays, touch screens, solar cells and solid-state lighting1,2. However,
further reductions in resistivity and in cost of SWCNT films are necessary for
high quality TCF products3. Here, we report an improved floating catalyst
chemical vapor deposition method to directly and continuously produce ultrathin
and freestanding SWCNT films at the hundred meter-scale. Both carbon conversion
efficiency and SWCNT TCF yield are increased by three orders of magnitude
relative to the conventional floating catalyst chemical vapor deposition. After
doping, the film manifests a sheet resistance of 40 ohm/sq. at 90%
transmittance, representing record performance for large-scale SWCNT films. Our
work provides a new avenue to accelerate the industrialization of SWCNT films
as TCFs.
