To Study the Role of Chemical Modification in Dispersion of Multi- Walled Carbon Nanotubes

Because of strong Vander Waal force, carbon nanotubes tend to aggregate into bundle that limits its applications in various fields. Homogenous dispersion of carbon nanotubes is an important issue. This paper reports the effect of chemical functionalization of multiwalled carbon nanotubes (MWCNTs) by introducing polar groups such as carboxyl groups in order to get better dispersibility in aqueous medium. Functionalization of MWCNTs was done by acid (HCl, HNO3, Aquaregia)and non-acid (NH4OH/H2O2) treatment.All treatments followed with variation of ultra-sonication time.The dispersion of MWCNTs was monitored by UV-VIS absorption spectroscopy. Functionalization removes the impurities present in pristine MWCNTs and adds different functional group on the surface of MWCNTs which helps further dispersion. The chemical change after functionalization of MWCNTwas investigated by FT-IR and Raman spectroscopy. Among four chemical reagents, HNO3acid treated MWCNTs show higher dispersion than other three. The dispersion increases with increasing the sonication time.