第一性原理研究气体小分子吸附的石墨烯负载金属原子体系

石墨烯负载的单个金属原子体系(M-gra)具有高的结构稳定性,显正电性的金属原子可作为活性位用在气敏器件和催化材料.本文采用基于密度泛函理论的第一性原理方法研究单个有毒气体小分子(NO和CO)在M-gra表面的吸附特性.研究结果表明:单个NO分子吸附的稳定性高于CO分子,由于其能够从反应衬底获得更多的转移电荷,因此,M-gra衬底对NO分子表现出高的灵敏度.此外,不同小分子吸附能够改变M-gra体系的电荷密度和自旋电荷分布,进而使得气体分子吸附体系表现出不同大小的磁矩.通过对比气体分子吸附前后M-gra体系的磁矩变化,能够有效判断吸附分子和反应衬底的类型.

First principles study of small gas molecules adsorb on metal-supported graphene systems

Single-atoms metal supported graphene (M-gra) structures exhibit high stability and the positively charged of metal dopants within graphene as active sites can be used as gas sensors and catalytic materials. The adsorption characters of toxic gas molecules (CO and NO) on M-gra surfaces are studied by using first-principle calculations based on density functional theory. The calculated results show that the adsorption of single NO molecule is more stable than that of CO, due to its gaining the more transferred electrons from the reactive substrates, thus the M-gra sheets display high sensing for NO molecule. In addition, different kinds of gas adsorptions can affect the charge density and spin charge distributions of M-gra systems, resulting in these gases adsorbed systems exhibit various magnetic moments. According to the change in magnetic moments before and after the gas adsorbed systems, the types of gas molecules and reactive substrates can be effectively distinguished.