非金属与金属原子共掺杂石墨烯体系的气敏特性研究

采用基于密度泛函理论的第一性原理方法研究了非金属N原子和金属原子(M=Mo,Al,Co,Fe,Au和Pt)共掺杂石墨烯体系(M-GN4)的电子结构和表面活性.研究发现:单个金属原子掺杂的GN4体系表现出不同的稳定性,相比掺杂的Au原子,其它的金属原子都具有很高的稳定性( 6. 0 e V).掺杂的金属原子失去电荷显正电性将有助于调控气体分子的吸附特性. Mo-GN4和Al-GN4衬底对吸附的O_2表现出较高的灵敏性,单个CO和O_2分子在Co-GN4和Fe-GN4衬底的吸附能差别较小.此外,吸附不同的气体分子能够有效地调控M-GN4体系的电子结构和磁性变化.

Study on Gas Sensing Properties of Non-metal and Metal atoms Codoped Graphene Sheets*

The electronic structures and reactive activities of metal dopants (M = Mo, Al, Co, Fe, Au and Pt) incorporated N4 centers in graphene sheets (M-GN4) are investigated using first-principles based on density functional theory. It is found that the metal dopants in GN4 sheet exhibit different stabilities. The doped metal atoms (Mo, Al, Co, Fe and Pt) have more stability ( 6.0 eV) than that of the Au dopant, and these dopants provide the transferred electrons to GN4 sheet and exhibit the more positively charged, which would regulate the adsorptive property of gas molecules. Compared to other M-GN4 substrates, the Mo-GN4 and Al-GN4 sheets exhibit the high sensitivity for the adsorbed O2, and the adsorption of CO and O2 have smaller energy difference on Co-GN4 (or Fe-GN4) sheet. Besides, the electronic structures and magnetic properties of M-GN4 systems can be effectively modulated by the adsorbed gas molecules.