Fabricating SWCNT thin film via Spray coating and Nitric Acid Vapor Treatment

There is an increased call for research aimed at finding viable substitute material for indium tin oxide (ITO) in optoelectronics applications, given the high cost and scarcity of ITO. Carbon nanotubes (CNTs) are among the most promising nanomaterials for creating thin films, not only in optoelectronics but also across various other applications. In comparison with alternative nanomaterials, CNTs offer distinct advantages attributable to their exceptional electronic, optical, and mechanical properties. The quality of thin films composed of single-walled carbon nanotubes (SWCNTs) predominantly hinges on the material itself, the fabrication method employed, and the post-treatment techniques applied. In this research, SWCNT thin films were produced utilizing an automated spray coating technique. These films underwent treatment with nitric acid vapor to enhance their optoelectronic characteristics. Evaluation of the SWCNT thin films encompassed electrical characterization using a 4-point probe, as well as optical characterization via UV spectroscopy and field emission scanning electron microscopy (FESEM). The optimal SWCNT film exhibited a sheet resistance value of 7.23 Ω/sq. and a transmittance percentage of 60.4 at a wavelength of 800 nm. This study thus paves the way for the fabrication of transparent conductors based on SWCNTs that rival the electronic properties of ITO.