Tek duvarlı karbon nanotüp saflaştırması ve geçirgen elektrot oluşturulması konusunda deneysel çalışmalar

Thin films of carbon nanotubes (CNTs) are suitable alternatives to indium tin oxide, the mostly used transparent electrode for opto-electronic devices and solar cells. A big advantage of CNTs is their thin film preparation from solution together with high flexibility. A three step chemical method using suitable surfactants in acidic media has been applied to purify and to dope carbon nanotubes synthesized by CVD method. A purity of more than 98 wt. % is verified by thermal gravimetric analysis, X-ray and Raman spectroscopy. We prepared afterwards highly transparent and continuous fine mesh structured CNT thin films using different surfactants via spin coating. The balance between thin film morphology and conductivity is controlled by the molecular interactions between the surfactants and CNT bundles. These interactions have been classified by contact angle measurements. Surfactants having strong interactions with CNT walls can form easily large-scale thin films, but the replacement of the insulating surfactant and doping of the CNTs electrode is more effective, when the molecular interactions are weak. Therefore, electrochemical properties of the prepared CNT electrodes are characterized using cyclic voltammetry, for comparison. Our studies demonstrate that CNT thin film preparation using SDS (Sodium dodecyl sulphate) leads to better performing CNT electrodes in comparison to electrodes investigated using DOC (Sodium deoxycholate), NMP (N-Methyl-2-pyrrolidone) and SDBS (Sodium dodecylbenzene sulfonate) as surfactants.