Cu/N共掺杂ZnS电子结构和光学性质的第一性原理计算

The first principles calculation on electronic structure and optical properties of Cu/N-codoped ZnS

摘要:

采用基于密度泛函理论（DFT）的第一性原理平面波超软赝势方法，计算了本征ZnS、N单掺杂、Cu-N共掺杂与Cu-2N共掺杂ZnS晶体的能带结构、电子态密度与光学性质。结果表明，Cu/N共掺杂体系降低了体系的带隙，增加了其光催化活性。对于Cu-2N掺杂，分析其态密度，发现共掺杂体系的总态密度在费米能级附近更加弥散，更多的态密度穿越费米能级，使共掺杂更容易获得p-型ZnS，同时费米能级附近的杂质态降低了跃迁能，使得共掺杂体系能有效提高其在可见光区的吸收系数。

Abstract:

Using the pseudo-potential plane-wave based on the density functional theory (DFT), the band structure, electron density of states and optical properties of intrinsic ZnS, N-, Cu -N and Cu-2 N co-doped ZnS were calculated. The calculation results show that the co-doped systems can reduce the band gap and enhance its Photocatalytic properties. According to the Analysis of the density of states, the co-doped system of Cu-2N make the state density become more diffuse, more state density through the Fermi level, which obviously led to formation of p-type ZnS. At some time, Cu/N co-doping greatly increase the absorption of visible region owing to the lower transition energy of co-doped systems .