title: An XANES study on the modification of single-walled carbon nanotubes by nitric acid.
abstract: X-ray absorption near-edge structure (XANES) spectroscopy has been applied to identify the modification process of single-walled carbon nanotubes (SWCNTs) treated by nitric acid. The carboxyl groups created by the nitric acid treatment have been found to be formed on both the carbonaceous fragments and the side walls of SWCNTs. The carbonaceous fragments could be removed by a following washing treatment with sodium hydroxide. XANES spectra indicate that carbonaceous fragments are the result of the synthesis process and/or of the nitric acid treatment. Tube walls of SWCNTs are weakly oxidized by the nitric acid treatment although, after removing carbonaceous fragments, a direct oxidation process of SWCNTs is observed. Experimental data address the removal of carbonaceous fragments on SWCNTs as an efficient method for side-wall modification of a SWCNT.
authors.affiliation: Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
authors.forename: Xianqing
authors.initials: X
authors.lastname: Liang
authors.forename: Jun
authors.initials: J
authors.lastname: Zhong
authors.forename: Yu
authors.initials: Y
authors.lastname: Wang
authors.forename: Ting
authors.initials: T
authors.lastname: Zhao
authors.forename: Peng
authors.initials: P
authors.lastname: Yao
authors.forename: Wangsheng
authors.initials: W
authors.lastname: Chu
authors.forename: Kurash
authors.initials: K
authors.lastname: Ibrahim
authors.forename: Haijie
authors.initials: H
authors.lastname: Qian
authors.forename: Ziyu
authors.initials: Z
authors.lastname: Wu
mesh_terms: D008422:Materials Testing / Q000379:methods*; D036103:Nanotechnology / Q000379:methods*; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure*; D017942:Nitric Acid / Q000737:chemistry*; D013052:Spectrometry, X-Ray Emission / Q000379:methods*; D013499:Surface Properties
chemical_list: D037742:Nanotubes, Carbon; D017942:Nitric Acid