Design of hybrid materials based on carbon nanotubes and polyoxometalates

The design of novel hybrid materials based on carbon nanotubes (MWCNT) and polyoxometalates (POM) is reported. The influence of MWCNT side-wall functionalization with nitric acid, sulfuric acid, and a mixture of both, on the immobilization of CsxPMo12O40 (POM) molecules was assessed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction studies (XRD). Nanotube oxidation with sulfuric acid showed the highest dispersion of POM particles on the MWCNT surface, while POM segregation occurred for nanotubes functionalized with a mild oxidizer such as nitric acid, suggesting the importance of covalent bonding through the surface acid groups. TEM analyses showed the filling of nanotubes under the soft conditions of the hybrids synthesis, broadening the range of applications for these materials, which constitute a novel alternative to composites based on polymeric inorganic metal oxides in nanoelectronic devices and optical applications.