Abstract
Controlled treatment of pristine single-walled carbon nanotubes (SWCNT) with HNO3 (11 M) for 20 hours at 50°C with subsequent repeated cycles of washing, centrifugation and ultrasonication in aqueous media have shown enrichment of the product with pure and debundled nanotubes of metallic variety. On the other hand, no such enrichment was observed when the tubes were treated with a mixture of concentrated nitric acid and sulfuric acid. The electrical varieties of the tubes were ascertained from the analysis of Raman and UV-Vis spectra and dc-resistivities. The purity of the product was gauged from transmission electron microscope images, energy dispersive spectra, thermogravimetric analysis and Raman spectra. A mechanism involving preferential attack of NO3− on the semiconducting tubes under the condition of the adopted protocol has been proposed from the comparison of the results after the treatment of the same pristine SWCNT with mixed acid (conc. HNO3 and H2SO4).
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
