A scalable fabrication of highly transparent and conductive thin films using fluorosurfactant-assisted single-walled carbon nanotube dispersions

A single-walled carbon nanotube (SWCNT)/sodium dodecylbenzenesulfonate (NaDDBS) dispersion containing a fluorosurfactant was bar-coated in order to produce a highly transparent and conductive thin film (TCF) for large-area application. The addition of a small amount of fluorosurfactant greatly reduced the surface tension of the CNT-dispersed solution, which produced a uniform film of CNTs by preventing agglomeration of CNTs during the drying process, and, furthermore, rendered bar-coating as the most practical large-area coating technique for a CNT solution. This particular fluorosurfactant addition maintained a CNT dispersion in the solution, which led to a dramatic improvement in the wettability of the CNT dispersion on the substrate towards high-performance TCF films. The thickness of the CNT films was controlled simply by adjusting the amount of CNTs in the solution. Moreover, the addition of a waterborne polymethyl methacrylate (PMMA) binder to the CNT dispersion improved the adhesion of the CNT films on a glass substrate.