Removal of sodium dodecyl sulfate surfactant from aqueous dispersions of single-wall carbon nanotubes

Abstract

A reagent-based treatment method was developed for the removal of sodium dodecyl sulfate (SDS) from aqueous dispersions of single-wall carbon nanotubes (SWCNTs). Based on a survey of various reagents, organic solvents emerged as the most effective at interrupting the SDS:SWCNT interaction without producing deleterious side reactions or causing precipitation of the surfactant. Specifically, treatment with acetone or acetonitrile allows for the facile isolation of SWCNTs with near complete removal of SDS through vacuum filtration, resulting in a 100x reduction in processing time. These findings were validated via quantitative analysis using thermogravimetric analysis, Raman spectroscopy, 4-point probe electrical measurement, and X-ray photoelectron spectroscopy. Subsequent thermal oxidation further enhances the purity of the reagent treated samples and yields bulk SWCNT samples with >95% carbonaceous purity. The proposed reagent treatment method thus demonstrates potential for large volume SWCNT processing.

Ambient Stabilization of Few Layer Phosphorene via Noncovalent Functionalization with Surfactants: Systematic 2D NMR Characterization in Aqueous Dispersion

“…Concurrently, any capping agents at FLP surfaces should be readily removable to exploit the intrinsic surface characteristics of FLPs . In this regard, vacuum filtration of aqueous dispersions, followed by thorough water rinsing, was employed for highly pure FLP based films. , The absence of low angle peaks (4.54° and 6.8°) in XRD (Figure g) for P/CTAB films after filtration and water rinsing indicates that surfactants were mostly removed (Figure S17). Optical microscope (OM) and SEM images of the gas sensing devices confirm the high uniformity of FLP film, without significant roughness and voids (Figure a).…”

Gel Chromatography for Separation of Single-Walled Carbon Nanotubes

“…By mixing the solvent with good solubility in the surface, the interaction between SDS and SWNT is interrupted, and as a result, pure SWNTs can be separated. A study by Rossi et al confirmed that acetone and acetonitrile could separate SWNTs from SDS with high purity [ 120 ].…”

Recent Advances in Applications of Sorted Single‐Walled Carbon Nanotubes

“…It is worth pointing out that these studies mostly involve sorting of SWCNTs through polymer/surfactant wrapping. The residual surfactants/polymer on the sidewalls of SWCNTs limits the full advantage of their unique properties . However, various strategies to remove the surfactants/polymer after separating the nanotubes are now being developed .…”

“…The residual surfactants/polymer on the sidewalls of SWCNTs limits the full advantage of their unique properties . However, various strategies to remove the surfactants/polymer after separating the nanotubes are now being developed . Mohite's group, for example, have studied the influence of two wrapping polymers, namely PFO and PFO‐BPy, commonly used to sort (7,5) and (6,5) SWCNTs on the performance of a solar cell .…”