Paper NS+NC-FrM8
Understanding the Factors Driving Performance and Reproducibility for Spray-Coated Single Wall Carbon Nanotube Transparent Conductive Films

Friday, October 24, 2008, 10:40 am, Room 311

Transparent and electrically conducting films of single wall carbon nanotubes (SWCNT) have been shown to be useful for integration into a variety of opto-electronic devices including solution-processed photovoltaics (PV). Several techniques have been introduced for the deposition of SWCNT networks including vacuum filtration, spin coating, ink jet printing and spray coating. We believe that spray coating represents the most cost effective technique for integrating transparent conductive SWCNT network films into large scale manufacturing. While a variety of groups have reported spray deposition techniques for SWCNT networks, there has been little detailed discussion of the issues relating to performance, reproducibility, and suitability for large scale manufacturing. A number of factors influence the electronic and optical properties of SWCNT networks. These factors include the tube source, purification protocol, ink formulation procedure (e.g. sonication power, duration, and choice of surfactant), the deposition method itself, and post-deposition processing. Our current work is focused on understanding the interplay of these factors in the spray coating process for SWCNT thin films. We pay special attention to optimizing film performance and reproducibility for photovoltaic applications. These studies have facilitated the reproducible fabrication of high performance organic photovoltaic devices on our SWCNT electrodes with efficiencies comparable to devices fabricated on traditional transparent conducting oxide films, such as indium tin oxide.