中国物理B ›› 2011, Vol. 20 ›› Issue (11): 117304-117304.doi: 10.1088/1674-1056/20/11/117304
王益军, 王六定, 杨敏, 严诚
Wang Yi-Jun(王益军), Wang Liu-Ding(王六定), Yang Min(杨敏), and Yan Cheng(严诚)
摘要: The effects of B and N dopings and H2O adsorption on the structural stability and the field emission properties of cone-capped carbon nanotubes (CCCNTs) were investigated by using the density-functional theoretical calculation. The adsorption of H2O can increase the structural stability and decrease the gap between the highest occupied molecular orbital and the lowest unoccupied molecular orbital (HOMO-LUMO gap) of the CCCNTs. The strength of total electric field on the top of the H2O-adsorbed CCCNTs is larger than that of the B-doped and the N-doped CCCNTs, electrons will be emitted primarily from the H2O-adsorbed CCCNTs at the same applied voltage. Therefore, the H2O adsorption can lower the threshold voltage for the CCCNTs. While the B and the N dopings produce opposite effects. The HOMO-LUMO gap of the N-doped CCCNTs is the widest among all the gaps of the CCCNTs.
中图分类号: (Nanotubes)