Areal Density Control of Liquid-Supported Carbon Nanotube Thin Films

Carbon nanotube (CNT) films have extensive applications due to their excellent electrical, mechanical, and thermal properties. A grand challenge is controlling areal density of CNT films to accommodate various applications. Here, a method based on the Marangoni effect is used to fabricate liquid-supported CNT films with tunable areal density, scalable area, and transferability to arbitrary substrates. By adjusting the viscosity and surface tension of the base liquid media, the Marangoni flow area of surfactant-assisted single-walled CNT (SWCNT) dispersion on the surface of base media was controllable and sparse or dense SWCNT films can be easily obtained. The thickness of the films is controlled by changing the concentration of the SWCNT dispersion. These SWCNT-based transparent-conductive films have widely controllable transmittance and conductivity and exhibit great photoelectric properties (T ∼ 82.4%, R_s ∼ 407 Ω/sq).