**2.6 Heterogenous ionic liquids (HILs) on carbon nanotubes (CNT) and multiwalled carbon nanotubes (MWCNT)**

Ionic liquid hybrid materials comprising of either CNT or MWCNT were developed, where the CNT or MWCNT were covalently anchored with the imidazolium-based ILs. The material thus obtained as per this methodology allows specific interactions between the IL thin film and the chemical composition of the MWCNT or CNT surfaces. Typically, the catalytic material was immobilized on the IL thin film. Lee et al. [22] have functionalized MWCNTs with ionic liquid moieties. Interestingly, the change of the ionic liquid anion modulates the solubility of the nanotubes in different solvents. This property makes the modified MWCNTs soluble in ionic liquid and created an IL-based catalytic system when Pd nanoparticles are immobilized on them.
