The Effect of Functional Group Polarity in Palladium Immobilized Multiwalled Carbon Nanotube Catalysis: Application in Carbon-Carbon Coupling Reaction

Carbon nanotubes (CNTs) are effective supports for nano metals and together they represent hybrids that combine unique properties of both. A microwave induced reaction was used to deposit nano palladium on carboxylated and octadecylamine functionalized multiwall CNTs, which were used to carry out C-C coupling reactions in DMF and toluene. These hybrids showed excellent catalytic activity with yield as high as 99.8% while its enhancement with respect to commercially available Pd/C catalyst reached as high as 109%, and the reactions times were significantly lower. Polarity of the functionalized form was found to be a significant factor with the polar carboxylated CNT showing better activity in DMF while the relatively nonpolar octadecyl amine was better in toluene. The results suggest the possibility of tailor making functionalized CNT when used as catalyst supports

Selective 1,3-butadiene hydrogenation by gold nanoparticles deposited & precipitated onto nano-carbon materials

GO and multiwall CNTs were modified by treatment with urea and annealing at different temperatures incorporating N adatoms. AuGO and AuCNT catalysts were prepared and their activity depended on the Au NP size and the characteristics of the support.

Dynamic characteristics of epoxy hybrid nanocomposites

An experimental study is conducted on epoxy composite, reinforced with nano alumina and Multiwall CNTs (0.5 and 1.0 wt%) in monolithic and hybrid forms to evaluate its stiffness and damping properties. Among monolithic reinforcements, Multiwall CNTs (1.0 wt %) have shown a significant increase in loss modulus, whereas nano alumina (0.5 wt%) has increased the storage modulus of the composite. With hybrid reinforcements, there is further increase in storage modulus (0.5 wt%) observed; however, a slight reduction in loss modulus (1.0 wt%) is noticed in comparison with CNT-reinforced nanocomposite. Based on these experimental observations, a two-layer hybrid composite configuration, consisting of nano alumina (0.5 wt% as layer 1) and Multiwall CNTs (1.0 wt% as layer 2) is fabricated and tested. The obtained results have indicated significant and simultaneous increase in storage and loss modulus, which brings out the importance of using the hybrid reinforcement configurations.