The origin of the catalysis of hydrogen peroxide reduction by functionalized graphene surfaces: A density functional theory study

The adsorption of hydrogen peroxide on pristine and modified graphene sheets is studied by means of density functional theory calculations. The system considered involves perfect and defective layers, which can be pristine or functionalized with carboxyl groups. It is found that functionalization increases (in absolute value) the adsorption energy of hydrogen peroxide and improves the reduction reaction due to a favourable change in the properties of the defective layer. These changes are analyzed and mechanisms for the reduction reaction of hydrogen peroxide on the different surfaces are proposed. The associated energy barriers are calculated by means of state-of-the-art calculation methods. (C) 2010 Elsevier Ltd. All rights reserved.