Stable Dispersions of Single-Wall Carbon Nanotubes Using Self-Assembled Amphiphilic Copolymer Surfactants for Fabricating Wafer-Scale Devices
Megha A. Deshmukh, Byeong-Cheol Kang, Jun-Young Jeon, Tae‐Jun Ha
Abstract
Carbon nanotubes (CNTs) have elicited immense scientific and technological interests due to their potential in numerous applications. However, colloidal stabilization of single-wall CNTs (SWCNTs) in solvents is a challenging problem which limits their practical applications. Here, we demonstrate self-assembled amphiphilic copolymer surfactants as emulsifying agents for excellent solubilization and stability of aqueous SWCNT dispersions. A well-defined poly(4-vinylpyridine)/polystyrene (P4VP-c-PS) was utilized as an effective surfactant to realize highly stable and reliable SWCNT dispersions exhibiting improved colloidal stability and adsorption capacity even after 5 months. We also investigate the effect of amphiphilic copolymer surfactant on the material characteristics of SWCNT dispersions and electrical characteristics of solution-processed SWCNT thin films by analyzing various characterizations. Finally, we demonstrate the feasibility of wafer-scale SWCNT-based devices with uniform and stable electrical properties by utilizing the proposed SWCNT dispersion based on P4VP-c-PS. Using self-assembled amphiphilic copolymer as a desirable dispersing surfactant is a promising approach to optimize the SWCNT dispersion for solution-processable nanoelectronic and nanomaterial applications over wafer-scale areas.