本文采用第一性原理计算方法,研究了zigzag型石墨烯纳米带在边缘采用不同基团(包括氢原子、羟基、酮基、氢和羟基共同饱和)进行修饰后电子特性的改变,计算了能带结构、态密度和电荷差分密度.结果分析表明,不同基团修饰的影响本质上可归结于不同的边缘杂化方式.边缘sp2杂化方式对GNRs体系内层原子的电子状态影响很小,没有改变zigzag-GNRs的金属性；而边缘sp3杂化的体系在能带结构中打开了一个带隙,此带隙随纳米带宽度的增加而逐渐减小.其中GNRs-H2体系和GNRs- H2O体系发生了由金属性向半导体性的转变,而GNRs-O体系费米能级升高并且进入了导带,依然呈现金属性.利用这种边缘修饰非常易于调控GNRs的电子能带结构.%Zigzag graphene nanoribbons with edges modified by different chemical groups are investigated by first principles calculations. The chemical groups considered include hydrogen, hydroxyl, ketone, and combination of hydrogen and hydroxyl. Band structures, DOS and charge difference density have been calculated. The results show that, the effect of different groups could be essentially ascribed to different types of edge. The structures of sp2 type have little influence on electron state of the inner atoms of GNRs whose metallicity still remains. However the structures of sp3 type generate a band gap which will decrease with the increase of ribbon's width. The shift from metallicity to semiconducting occurs in both structures of GNRs-H2 and GNRs-H2O, while the structure of GNRs-0 remains its metallicity as its Fermi level increases into the conduction band. By using this method of edge hybridization, the GNRs' band structure is prone to be controlled.
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