Ni@CNT nanocomposites as novel highly effective carbocatalysts for Hydrogenation/Dehydrogenation reactions

A series of carbon-encapsulated Ni nanoparticles deposited on carbon nanotubes (Ni@CNT) with various Ni concentrations were prepared by a simple impregnation method. The structural and functional properties of Ni@CNT were determined by a typical set of physicochemical methods. The catalytic performance of Ni@CNT was evaluated in the model reactions of ethylene hydrogenation and dehydrogenation of ethane as a reverse reaction, as well as in liquid-phase hydrogenation of p-nitrotoluene and α-methylstyrene. The surface of the Ni@CNT samples does not contain Ni and corresponds to CNT. The content of Ni was found to strongly influence the catalytic properties of Ni@CNT. Samples containing 1% of Ni demonstrated the highest activity for both the hydrogenation of the C=C bond and the dehydrogenation of ethane. Our study has demonstrated that the facile fabrication of Ni@CNT can produce efficient catalysts for the hydrogenation of various organic compounds using molecular hydrogen. Our results suggest that the catalytic properties of these nanocomposites are primarily associated with the carbon surface and enhanced by the Schwab effect.