石墨烯中的单空位缺陷对铂原子催化解离氧分子的影响

采用密度泛函理论中的B3LYP方法研究了石墨烯中的单空位缺陷对铂原子(Pt)催化解离O_2分子的影响.计算发现O_2分子首先通过2+1]或2+2]环加成作用吸附在以单空位缺陷石墨烯为载体的Pt上(Pt-SV),并以不同的路径进行解离,吸附能分别为-158.23和-152.45kJ/mol.由于石墨烯片上单空位缺陷的存在,O_2分子更容易吸附在单空位缺陷处的Pt上,并且O_2在Pt-SV上解离的能垒(130.25kJ/mol)也明显比在Pt-pristine上解离的能垒低(76.23kJ/mol).因此石墨烯上单空位缺陷的存在提高增加了Pt的催化能力.

The effect of the single vacancy defect in graphene on the platinum catalyzed dissociation of oxygen

The influence of the single vacancy defects in graphene on the platinum catalyzed dissociation of oxygen has been studied by density functional theory calculation with B3LYP method.The computational results shown that O2 molecule firstly adsorbed on Pt-doped graphene by 2 +1] or 2+2] cycloaddition,with the adsorption energies of-158.23 and-152.45 kJ/mol,respectively.Moreover,the adsorbed O2 molecule can be dissociated in different pathways.Because the existing single vacancy defects of graphene,the dissociation barrier of O2 on Pt-SV is lower than the oxygen molecule dissociation on the platinum catalyst supported the pristine graphene (130.25 and 76.23 kJ/mol,respectively).Thus,the presence of single vacancy defect on graphene greatly increase the catalytic ability of Pt atom.