Effects of hydroxyl group on H_2 dissociation on graphene:A density functional theory study

• 作 者: Ning Wang Likun Wang Qinggang Tan Yun-Xiang Pan
• 机 构: College of Materials Science and Engineering,Key Laboratory for Advanced Civil Engineering Materials
• 出 处: Journal of Energy Chemistry
• 发表日期: 2013年03期
• 关键词: dissociation hydroxyl ortho facile favorable reversible bonds neighboring conjug

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 H_2 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 H_2 dissociation on both the pristine and hydroxyl-modified graphene.The energy barrier of H_2 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 H_2 dissociation on the hydroxyl-modified graphene.

Graphene-based materials are promising for hydrogen production and storage. This work, using density functional theory calculations, we explored how a hydroxyl group influences H_2 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 H 2 dissociation on both the pristine and hydroxyl-modified graphene. The energy barrier of H 2 dissociation at para-site on the pristine graphene is 3.10 eV while that on the hydroxyl-modified graphene is 2.46 eV, indicating a more facile H 2 dissociation on the hydroxyl-modified graphene.