Effects of hydroxyl group on H2 dissociation on graphene： A density functional theory study

摘要

Graphene-based materials are promising for hydrogen production and storage.In this work,using density functional theory calculations, we explored how a hydroxyl group influences H2 dissociation on graphene.Presence of the hydroxyl group makes the binding of H atom with graphene stronger,as the binding energy of H atom with the hydroxyl-modified graphene is higher than that with the pristine graphene. The para-site is the most favorable site for H2 dissociation on both the pristine and hydroxyl-modified graphene.The energy barrier of H2 dissociation at para-site on the pristine graphene is 3.10 eV whereas that on the hydroxyl-modified graphene is 2.46 eV,indicating a more facile H2 dissociation on the hydroxyl-modified graphene.