Highly conductive, transparent flexible films based on open rings of multi-walled carbon nanotubes

• Published in: Thin solid films 2011-09, Vol.519 (22), p.7717-7722
• Main Authors: Ko, Wen-Yin, Su, Jun-Wei, Guo, Chian-Hua, Fu, Shu-Juan, Hsu, Chuen-Yuan, Lin, Kuan-Jiuh
• Format: Article
• Language: English
• Subjects: Bending; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross sections; Cross-disciplinary physics: materials science; rheology; Electrical conductivity; Electrical measurements and properties; Electrical properties of specific thin films; Electrical resistivity; Electron and ion emission by liquids and solids; impact phenomena; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Exact sciences and technology; Field emission, ionization, evaporation, and desorption; Flexibility; Flexible thin films; Liquid phase epitaxy; deposition from liquid phases (melts, solutions, and surface layers on liquids); Materials science; Methods of deposition of films and coatings; film growth and epitaxy; Multi wall carbon nanotubes; Nanoscale materials and structures: fabrication and characterization; Nanotubes; Networks; Open-rings; Physics; Porous networks; Resistivity; Scanning electron microscopy; Transparent conducting film
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/j.tsf.2011.05.064

Open rings of multi-walled carbon nanotubes were stacked to form porous networks on a poly(ethylene terephthalate) substrate to form a flexible conducting film (MWCNT-PET) with good electrical conductivity and transparency by a combination of ultrasonic atomization and spin-coating technique. To enhance the electric flexibility, we spin-coated a cast film of poly(vinyl alcohol) onto the MWCNT-PET substrate, which then underwent a thermo-compression process. Field-emission scanning electron microscopy of the cross-sectional morphology illustrates that the film has a robust network with a thickness of ~ 175 nm, and it remarkably exhibits a sheet resistance of approximately 370 Ω/sq with ~ 77% transmittance at 550 nm even after 500 bending cycles. This electrical conductivity is much superior to that of other MWCNT-based transparent flexible films.