Relative Catalytic Activities of Carbon Nanotube-Supported Metallic Nanoparticles for Room-Temperature Hydrogenation of Benzene

Carbon nanotube-supported metallic nanoparticles including Pt, Rh, and bimetallic Pd−Rh are effective catalysts for the hydrogenation of neat benzene at room temperature, which cannot be achieved by carbon-based Pd and Rh catalysts available commercially. The rate of the hydrogenation reaction is zero-order with respect to benzene and first-order with respect to hydrogen and the catalyst. CNT-supported Pd and Au nanoparticles show negligible activity for room-temperature hydrogenation of benzene. The bimetallic Pd−Rh/CNT nanoparticle catalyst exhibits a strong synergistic effect relative to the individual single metal nanoparticles for catalytic hydrogenation of benzene, toluene, and 1-phenyl-1-cyclohexene.