Author/Authors :
Erokhin، نويسنده , , A.V. and Lokteva، نويسنده , , E.S. and Yermakov، نويسنده , , A.Ye. and Boukhvalov، نويسنده , , D.W. and Maslakov، نويسنده , , K.I. and Golubina، نويسنده , , E.V. and Uimin، نويسنده , , M.A.، نويسنده ,
Abstract :
Me@C nanocomposites were prepared by evaporation of overheated liquid drop of Me in the flow of inert gas containing a hydrocarbon. The resulting carbon-coated nickel and iron nanoparticles contain metal cores of about 5 nm in size that are wrapped in a few layers of graphene-like carbon. Experimental data and theoretical results give evidence of the ability of carbon coating in nanocomposites Fe@C and Ni@C to H2 activation by dissociative adsorption due to the presence of space and structure defects and/or the presence of transition metal in subsurface layer. Since molecular hydrogen dissociation is the key step of hydrogenation reactions, both Ni@C and Fe@C provide high conversion of phenylacetylene (PA) (about 100%) during hydrogenation at the temperatures above 150 and 300 °C, respectively. Fe@C provides excellent styrene (ST) selectivity: 86% at 99% PA conversion at 300 °C. ST selectivity is moderate on Ni@C (about 60%) in the temperature range of 100–150 °С and low at higher temperatures.
