Polyethylene glycol grafting and attachment of encapsulated magnetic iron oxide silica nanoparticles onto chlorosilanized single-wall carbon nanotubes

It is demonstrated that functionalization of single-wall carbon nanotubes (SWCNTs) can be carried out using simple chlorosilane chemistry, which allows coupling of the SWCNTs with external chemical species. As a result, organic polymers and magnetically iron oxide-in-silica nanoparticles are specifically bonded onto SWCNTs. It is also found that the SWCNTs functionalized with long PEG chains greatly enhance dispersion of the carbon structure in water. Furthermore, the SWCNT–COO–Si(Fe3O4@SiO2) can be quickly separated and redispersed from their aqueous colloid with the application of external magnetic field.