Hydrogen Coverage Dependent C=C Hydrogenation Activity on Rh(111)

Abstract Many C C hydrogenation reactions at a heterogeneous surface are regarded to be independent of the H coverage. In this letter, we report that the initial hydrogenation barrier of cyclohexene is H-coverage dependent on Rh(1 1 1). Using density functional theory calculations, we found that the reaction barrier of the initial hydrogenation decreases linearly with the increase of H coverage on Rh(1 1 1). In contrast, all of the hydrogenation barriers of allyl alcohol on Rh(1 1 1) are found to be significantly less dependent to H-coverage.