Direct Styrene Hydrogenation on a Metal-Free Boron-Nitrogen Doped Carbon Catalyst

We present a study of the direct styrene hydrogenation to ethylbenzene by a metal-free catalyst. The catalyst is a nanohybrid made up of ultra-dispersed diamonds (UDD) and graphitic sheets. The method to prepare the catalyst introduces the key active site (bearing B and N atoms) into the sp2 rich layer over the surface of UDD. Results show excellent catalytic activity for the direct hydrogenation of styrene to ethylbenzene in the presence of isopropyl alcohol, where hydrogen comes directly from the oxidation of the alcohol to acetone. The combination of experimental characterization and quantum chemical simulation indicates that a key role is played by direct B=N bonds and pyrrolic-N is the most probable active site in the reaction.