贵金属(Cu、Ag、Au)掺杂ZnO电子结构和光学性质的第一性原理研究

First-principles study of the optical properties of ZnO doped with precious metal(Cu、Ag、Au)

采用基于密度泛函理论的总体能量平面波超软赝势方法,对贵金属(Cu、Ag、Au)掺杂ZnO进行了几何结构优化,并计算了相应的能带结构、受主能级、形成能、电子态密度和光学性质.结果表明:贵金属掺杂后带隙减小且体系费米能级附近电子态密度主要来源于Cu3d、Ag4d和Au5d态电子的贡献.与未掺杂ZnO相比,介电函数虚部、反射峰强度和吸收系数在可见光和紫外区域增强.能量损失谱计算表明,贵金属(Cu、Ag、Au)掺杂后ZnO的等离子体共振频率峰发生蓝移.

The geometrical structures of pure ZnO and precious metal （Cu,Ag,Au） doped 32-atom supercell of ZnO were optimized by using the ultra-soft pseudopotential method of total-energy plane wave based on the density functional theory. Band structure, acceptor level, formation energy, density of states and optical properties were calculated and discussed in detail. The results revealed that the band gap of precious metal doped ZnO is decreased and the density of states near Fermi level is derived from Cu3d,Ag4d and Au5d. The imaginary part of the dielectric function, reflectivity and absorption coefficient are increased in visible and ultraviolet region after doping. Energy loss spectroscopy revealed the plasma resonance frequency peak of precious metal doped ZnO shows blue shift.