Correlation between CNT characteristics and the conductivity of CNT electrode films: Optimization of fabrication conditions for enhancing electrical properties

Carbon nanotubes (CNTs) possess exceptional electrical conductivity, making them attractive candidates for various electrical and electronic applications. CNT conductivity is affected by factors such as chirality, diameter, and purity. This study focused on maximizing the performance of single-walled carbon nanotube (SWNT) electrodes by optimizing key parameters that influence their conductivity. We systematically investigated the impact of synthesis methods, SWNT length and diameter, dispersion conditions, surface defects, and electronic structure on the electrical conductivity of fabricated electrodes. Our results indicate that arc-discharge (AD) SWNTs, characterized by larger diameters and longer lengths, exhibit greater resilience to surface damage during dispersion compared to HiPco SWNTs. This enhanced resilience reduces contact resistance and improves electrode performance. By optimizing dispersion conditions to minimize surface damage and length reduction, and by isolating high-purity metallic SWNTs from commercial mixtures, we successfully produced highly conductive AD SWNT film electrodes with a sheet resistance of 335 Ω/sq at 90 % transparency. Ultraviolet–visible-near infrared and Raman spectroscopy analyses were conducted to elucidate the factors contributing to these optimized conditions. These findings hold significant implications for the development of advanced carbon materials for anodes and cathodes in next-generation batteries.