Interactions between Multiwall Carbon Nanotubes and Poly(diallyl dimethylammonium) Chloride: Effect of the Presence of a Surfactant

Abstract

The interactions between multiwall carbon nanotubes (MWCNTs) and poly(diallyl dimethylammonium) chloride (PDDA) have been studied in the presence of different ionic and nonionic surfactants, such as sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB), Tween 20, 40, 60, and 80, and Triton X-100. On the basis of scanning electron microscopy (SEM) results, the MWCNT/PDDA sample treated with Triton X-100 has been observed to show good dispersion of nanotubes. This is due to the π-π stacking between the benzene ring of Triton X-100 and the hexagonal carbon rings of nanotubes and better coating of PDDA on MWCNTs, as is confirmed by the Raman studies. Energy dispersive X-ray (EDX) spectroscopic data shows the presence of higher oxygen content in the MWCNTs/PDDA/Triton X-100 sample. The maximum upshift in the C1s peak position and down-shift in the N1s peak position for the MWCNTs/PDDA/Triton X-100 sample has been observed from X-ray photoelectron spectroscopy (XPS) results and is due to the intermolecular charge transfer from carbon in MWCNTs to nitrogen in PDDA. The presence and nature of a surfactant in the MWCNTs/PDDA system has been found to affect their interactions. The above results suggest that the MWCNTs/PDDA/Triton X-100 system is suitable as a metal-free electrocatalyst for the oxygen reduction reaction (ORR) in fuel cells.

In vitro drug release characteristic and cytotoxic activity of silibinin-loaded single walled carbon nanotubes functionalized with biocompatible polymers

“…The degree of functionalization and imperfections can be estimated by measuring the intensity ratio (I D /I G ) of the D and G-band of the nanotubes [12]. The positions of D and G-bands as well as I D /I G ratios for all samples are listed in Table 1.…”

“…They have the potential to deliver therapeutic molecules to the targeted site of action by conjugation to ligands of cancer cell surface receptors or antigens [11], which makes them an ideal delivery system to treat cancer diseases at the cellular level. In addition, they can be covalently or non-covalently functionalized with hydrophilic materials such as polysorbate surfactant and polyethylene glycol (PEG) [12, 13], to improve their biocompatibility and dispersability in physiological environment.…”

Crosslinking assisted fabrication of ultrafine poly(vinyl alcohol)/functionalized graphene electrospun nanofibers for crystal violet adsorption

“…However, the composite mat after adsorption clearly shows the signal from N at about 400 eV, which could be attributed to N in the CV structure. High‐resolution XPS spectrum of N 1 s [Figure (e)] reveals three deconvoluted curves at 400.2 eV (CN bond), 401.8 eV (protonated amine, , from functional group of the graphene), and 403.0 eV (positive charged N atom, N + , from CV structure) …”

Investigation of adsorption and photocatalytic activities of in situ cetyltrimethylammonium bromide-modified Bi/BiOCl heterojunction photocatalyst for organic contaminants removal

“…7d), which is attributed to the positively charged nitrogen (N + ) in CTAB. 43 The C 1s spectra of Bi/BiOCls could be tted with a main band at 284.7 eV or 284.8 eV (Fig. 7e), attributed to C-C or C-H bond, and include that another peak at 286.0 eV or 285.8 eV could be associated to C-N bond.…”