采用基于密度泛函理论的第一性原理计算,对本征碳化硅纳米管和掺氮碳化硅纳米管的电子结构进行了计算.计算表明本征(8,0)碳化硅为直接带隙半导体,能带间隙为0.94 eV;掺氮浓度为1.56%和3.12%的碳化硅纳米管的能带间隙减小为0.83 eV和0.74 eV.从差分电荷密度可以看出,能带间隙的减小是氮硅键与碳硅键相比共价成键能力降低的结果. The electronic structure of intrinsic silicon carbide nanotubes and nitrogen-doped silicon carbide nanotubes was calculated by first-principles calculations based on density functional theory. The calculations show that the intrinsic (8,0) silicon carbide is a direct band gap semiconductor, The band gap was 0.94 eV, and the band gaps of silicon carbide nanotubes with nitrogen doped concentrations of 1.56% and 3.12% were reduced to 0.83 eV and 0.74 eV, respectively.As can be seen from the differential charge density, the band gap reduction was nitrogen The result of a decrease in the covalent bonding ability of the silicon bond compared to the carbon-silicon bond.