电子和空穴注入对氮掺杂SnO_2材料光电性能的影响

Effect of Electron and Hole Injection on the Photoelectric Performance of N-doped SnO_2 Materials

采用基于密度泛函理论的线性缀加平面波(FLAPW)方法研究了电子、空穴对N掺杂SnO_2光电性能的影响,结果表明注入空穴比注入电子的Sn16O31N体系禁带宽度减小了0.02 e V,比未注入电子、空穴的Sn16O31N体系变窄了0.04 e V,导带也相对展宽,体系呈现出半金属特性,SnO_2材料导电性能有所提高。注入空穴的体系光学特性也发生了较大的变化,其吸收系数、能量损失函数及折射率在低能区域低于本征和电子注入体系,整个体系的态密度向低能方向移动发生了红移,吸收边变宽,体系的光学响应增大。

The effect of electrons and holes on the photoelectric properties of N-doped SnO2 were investigated through the full-potential linearized augmented plane wave （FLAPW） method based on density functional theory. The results indicate that the energy gap of injected holes is reduced 0.02 eV than injected electrons, and reduced 0. 04 eV than Sn16 O31 N. The conduction band is relatively broadening, show the half-metal property and the electrical conductivity of SnO2 is enhanced. The photoelectric properties of injected holes have large change, such as the absorptivity, energy loss function and refractive index reduce in low energy region, state density moves to low energy direction, the optical absorption edge broad, that shows red shift phenomenon, and optical response increases.