In this article, we reported the structural and conductive properties of benzene derivatives/carboxylated zigzag SWCNTs. It was noticed that the carboxylated carbon nanotubes were appropriate adsorbents for benzene derivatives. We presented novel density of states and band structures for modified SWCNTs by both carboxylic group and benzene derivatives. The result showed that nitrobenzene/COOH-SWCNT comprising superb electronic properties can be effectually applied for electronic devices and solar cells, instead of aniline/SWCNT combined system. (C) 2015 Elsevier B.V. All rights reserved.