【摘要】 为了研究NO,NO₂,CO,H₂S,SO₂气体在Mn修饰的石墨烯表面的吸附行为，利用基于密度泛函理论的第一性原理平面波超软赝势计算方法模拟了其吸附过程，计算了吸附能、Mulliken分布、差分电荷密度、总电子电荷密度和恢复时间并与未经修饰石墨烯吸附性质进行了比较。结果表明，与未经修饰的石墨烯表面相比，Mn修饰的石墨烯表面对吸附的5种气体表现出了更高的敏感性。Mn原子修饰的含有一个C原子空位与两个C原子空位的石墨烯吸附NO,NO₂,CO,H₂S,SO₂后，气体与基底之间形成了化学键，为化学吸附。同一吸附基底吸附能大小排序为：NO>NO₂>CO>SO₂>H₂S,吸附后电荷转移量大小排序为：NO₂>NO>CO>SO₂>H₂S。并且C空位的增加降低了Mn原子修饰的石墨烯表面与气体之间的相互作用。利用过渡态理论预测了室温下Mn原子修饰的石墨烯基底作为5种有毒气体的传感器的恢复时间，为基于石墨烯基底的有毒气体检测传感提供了理论支撑和实验指导。更多还原

【Abstract】 In order to study the adsorption behavior of NO, NO₂, CO, H₂S, SO₂ on Mn modified graphene surface, in this paper, the first-principles plane-wave ultrasoft pseudopotentials of the density-functional theory is used to simulate the adsorption process. The adsorption energy, Mulliken distribution, differential charge density, total charge density and recovery time were calculated and compared with those of unmodified graphene. The results show that the Mn-modified graphene surface is more sensitive to the adsorption of 5 gases than the unmodified graphene surface. After adsorption of NO, NO₂, CO, H₂S, SO₂ on Mn-modified graphene containing one C-vacancy and two C-vacancy, chemical bonds are formed between the gas and the substrate, which is chemical adsorption. The order of the adsorption energy of the same substrate is: NO>NO₂>CO>SO₂>H₂S, and the order of the charge transfer quantity after adsorption is: NO₂>NO>CO>SO₂>H₂S. The increase of C vacancy decreases the interaction between Mn-modified graphene surface and gas. The recovery time of Mn-modified graphene substrate as a gas sensor at room temperature is predicted. This provides theoretical support and experimental guidance for the detection of toxic gases based on graphene substrate.更多还原