采用密度泛函理论框架下的第一性原理平面波超软赝势方法、计算了本征ZnO,Cu10^21 cm-3单掺杂ZnO,Co单掺杂ZnO,Cu.Co共掺杂ZnO的电子结构和光学性质.结果表明,在本文掺杂浓度数量级下,Cu,Co单掺杂可以提高ZnO的载流子浓度,从而改善ZnO的导电性,Cu—Co共掺杂时ZnO半导体进入简并状态,呈现金属性.这三种掺杂ZnO均会在可见光和近紫外区域出现光吸收增强现象,其中由于Cu离子与Co离子之间的协同效应,Cu—Co共掺杂Zn0对太阳光的吸收大幅增加,因此Cu—Co共掺杂zn0可以用于制备高效率的太阳电池.
The electronic structures and optical properties of intrinsic, Cu, Co doped and Cu-Co codoped ZnO compounds are calculated using first-principles plane-wave ultrasoft pseudopotential method based on the the density functional theory. The results show that the conductivity of ZnO can be improved by doping Cu and Co because of the increase of the carrier concentration under the order of magnitude of doping concentration in this paper. Cu-Co codoping leads to the degeneration and makes ZnO metallic. Thses three kinds of dopings can cause light absorption enhancement phenomenon in the visible and near ultrasoft regions, in which Cu-Co codoping greatly increases the absorption of solar light due to the synergistic effect between Cu ions and Co ions, which can be used to prepare the high efficiency solar cells.