Oxidation, Deformation, and Destruction of Carbon Nanotubes in Aqueous Ceric Sulfate

Abstract

A simple wet chemical method involving only ultrasonic processing in dilute ceric sulfate (CS) was used to functionalize carbon nanotubes (CNTs). Unexpectedly, single-walled and multiwalled carbon nanotubes (SWCNTs and MWCNTs) were cut, oxidized, and disintegrated by sonication in 0.1 N CS for 2-5 h. Transmission electron microscopy (TEM), atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction spectroscopy (XRD), Raman scattering, and photoacoustic Fourier transform infrared spectroscopy (FTIR) were used to probe wall damage during the chemical processing. Cyclic voltammetry and impedance spectroscopy were used to evaluate the conductivity of the CS-treated CNTs. This one-step process resulted in the destruction of SWCNTs to produce nonconducting amorphous carbon. MWCNTs were oxidized and converted to graphitic materials and amorphous carbon with retained conductivity.

Efficient and facile one pot carboxylation of multiwalled carbon nanotubes by using oxidation with ozone under mild conditions

“…8). The data can be fitted to values close to those of graphite and more specifically, to those reported in the literature for CNTs [8,9,31].…”

“…The C1s envelope in the C1s XPS spectrum of oxidized MWCNTs can be fitted by convoluting four peaks, each representing a separate carbon bond, namely, C5 5C (284.6 eV), -C-OH (285.8 eV), -C5 5O (287.1 eV), HO-C5 5O (288.9 eV), (290.4 eV) corresponding to carbon atoms attached to different oxygen-containing moieties [11,12,31,32]. Finally, the p-p* transition peak was detected at 292 eV.…”

Raman spectroscopy of covalently functionalized single‐wall carbon nanotubes

“…Also, annealing the sample restores the Raman intensities, 61,63,64,71 -74,81,83 in contrast to treatments where a complete disintegration of the SWCNTs occurs. 86,87 In Fig. 2 the Raman spectra of functionalized and pristine SWCNTs are shown (left), together with the absorption spectra of the respective materials.…”

Understanding the Electrochemical Reactivity of Bamboo Multiwalled Carbon Nanotubes: the Presence of Oxygenated Species at Tube Ends May not Increase Electron Transfer Kinetics

“…However we are aware of only one study exploring the oxygenation of multiwalled carbon nanotubes. Luong et al [14] have explored the acid treatment of MWCNTS with ceric sulfate. After 2 h treatment they observed the presence of large amounts of oxygen on the MWCNTs.…”