Artigo
Evaluation of residual iron in carbon nanotubes purified by acid treatments
Fecha
2011-11-01Registro en:
Applied Surface Science. Amsterdam: Elsevier B.V., v. 258, n. 2, p. 641-648, 2011.
0169-4332
10.1016/j.apsusc.2011.07.032
WOS:000296525800001
4378078337343660
0000-0001-8338-4879
Autor
Universidade Estadual Paulista (Unesp)
Instituto Nacional de Pesquisas Espaciais (INPE)
Instituto Tecnológico de Aeronáutica (ITA)
Resumen
A detailed analysis by X-ray photoelectron spectroscopy was carried out on multi-walled carbon nanotube (MWCNT) surfaces after non-oxidative and oxidative purification treatments in liquid-phase. The MWCNT were produced by pyrolysis of camphor and ferrocene, that provides a high yield but with high iron contamination (similar to 15% wt). The elimination and/or oxidation of iron nanoparticles were monitored by Fe2p and O1s core level. Oxygen-based functional groups attachment was also investigated by C1s fitting. The effectiveness of each treatment in iron removal was evaluated by thermogravimetric analysis (TGA) and atomic absorption spectroscopy (AAS). The integrity of the MWCNT structure was verified by Raman spectroscopy (RS) and transmission electron microscopy (TEM). A purity degree higher than 98% was achieved only with non-oxidative treatments using sonification process. (C) 2011 Elsevier B.V. All rights reserved.