Hydrodeoxygenation of phenol to benzene and cyclohexane on Rh (111) and Rh (211) surfaces: Insights from density functional theory

Herein we describe the C–O cleavage of phenol and cyclohexanol over Rh(111) and Rh(211) surfaces using density functional theory calculations. Our analysis is complemented by a microkinetic model of the reactions, which indicates that the C–O bond cleavage of cyclohexanol is easier than that of phenol and that Rh(211) is more active than Rh(111) for both reactions. This indicates that phenol will react mainly following a pathway of initial hydrogenation to cyclohexanol followed by hydrodeoxygenation to cyclohexane. We show that there is a general relationship between the transition state and the final state of both C–O cleavage reactions, and that this relationship is the same for Rh(111) and Rh(211).