深圳大学学报理工版

利用基于密度泛函理论的第一性原理计算方法,研究单个CO 和O2气体分子在多种金属原子修饰的石墨烯表面的吸附作用. 结果表明,空位缺陷结构的石墨烯能够显著提高金属原子的稳定性,失去部分电荷的金属原子有助于调控气体分子的吸附特性.对比发现,单个金属Al和Mo原子掺杂的石墨烯体系对O2分子具有极高的灵敏性和选择性. 通过不同气体分子的吸附能够调控石墨烯体系的电子结构和磁性. 研究结果测试了不同金属原子修饰石墨烯表面的反应活性,为设计新型金属-石墨烯功能器件提供参考.

We investigate the adsorption of single CO molecule and O2 molecule on metal atom decorated graphene(MA-graphene)surfaces by means of the first-principles method based on density functional theory. The results show that vacancy defects in graphene can improve the stability of metal atom absorption, and make the metal atoms be more positively charged due to their losses of electrons, thus facilitating the adsorption of gas molecules. Compared with other MA-graphenes, the single Al and Mo atom embedded graphene sheets exhibit higher sensitivity and selectivity for the O2 molecules. Furthermore, the electronic structure and magnetic property of MA-graphene systems can be regulated by the adsorbed gas molecules. Our results validate the reactivity of graphene surface absorbed by single metal atoms and provide a theoretical view for designing new metal-graphene functional devices.

引言
1 计算参数与模型
2 结果与讨论
3 结语

图1 金属Fe原子掺杂石墨烯体系的俯视和侧视图及其电荷密度图(等高线均以5.6×108 C/m3画出)<br/>Fig.1 (Color online)Top and side views of the Fe embedded-graphene and the valence charge density plots(The contour lines in plots are drawn at about 5.6×108 C/m3)

图1 金属Fe原子掺杂石墨烯体系的俯视和侧视图及其电荷密度图(等高线均以5.6×108 C/m3画出)
Fig.1 (Color online)Top and side views of the Fe embedded-graphene and the valence charge density plots(The contour lines in plots are drawn at about 5.6×108 C/m3)

表1 金属原子掺杂石墨烯体系的Eads、LM-C、Δq、hD和Eform<br/>Table 1 Eads、LM-C、Δq、hD and Eform

表1 金属原子掺杂石墨烯体系的Eads、LM-C、Δq、hD和Eform
Table 1 Eads、LM-C、Δq、hD and Eform

图2 O2和CO分别吸附在Fe-graphene衬底的俯视和侧视图<br/>Fig.2 (Color online)Top and side views of the stable configurations of O2 adsorbed Fe-graphene and

图2 O2和CO分别吸附在Fe-graphene衬底的俯视和侧视图
Fig.2 (Color online)Top and side views of the stable configurations of O2 adsorbed Fe-graphene and

表2 O2和CO吸附在MA-graphene衬底的稳定性参数<br/>Table 2 The stable configuration data of O2 adsorbed MA-graphene and CO adsorbed MA-graphene

表2 O2和CO吸附在MA-graphene衬底的稳定性参数
Table 2 The stable configuration data of O2 adsorbed MA-graphene and CO adsorbed MA-graphene

图3 金属原子掺杂石墨烯体系的态密度图<br/>Fig.3 DOS plots of MA-graphene systems

图3 金属原子掺杂石墨烯体系的态密度图
Fig.3 DOS plots of MA-graphene systems

图4 单个O2和CO吸附在Fe-graphene衬底的态密度图<br/>Fig.4 Spin-resolved DOS plots of O2 adsorbed Fe-graphene and CO adsorbed Fe-graphene

图4 单个O2和CO吸附在Fe-graphene衬底的态密度图
Fig.4 Spin-resolved DOS plots of O2 adsorbed Fe-graphene and CO adsorbed Fe-graphene

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备注

引言

1 计算参数与模型

2 结果与讨论

3 结语

期刊信息

备注

引言

1 计算参数与模型

2 结果与讨论

3 结 语

期刊信息

3 结语