Cu/Al共掺ZnO光学性质的第一性原理计算

利用Material Studio2017软件中基于密度泛函理论的CASTEP模块,仿真建立2×2×2的ZnO超晶胞,在相同情况下用不同比例的Cu/Al(Cu-Al、2Cu-Al和Cu-2Al)替换超晶胞中的Zn原子,得到Zn_1－x－yCu_xAl_yO体系,对本征ZnO和各掺杂体系ZnO的电子结构和光学性质进行了第一性原理计算.结果表明:上述各掺杂体系在低能区的光吸收均发生红移,体系为简并半导体.可针对ZnO的不同用途,通过控制Cu/Al掺杂比来提高该体系在可见光范围内的光吸收或光透射.在可见光范围内,Zn_{0.812 5}Cu_0.125Al_{0.062 5}O体系的光吸收最强,可用于制作太阳能电池板的光电极材料等;Zn_{0.812 5}Cu_{0.062 5}Al_0.125O体系的透光率高,可用于制作高透光ZnO半导体薄膜.

First-principles calculation of optical properties of Cu/Al co-doped ZnO

Using CASTEP module based on density functional theory in Material Studio 2017 software, the simulation of ZnO supercell (2×2×2) was established, Zn atoms in supercell were replaced by different proportions of Cu/Al (Cu-Al, 2Cu-Al and Cu-2Al) in the same case, a Zn_1－x－yCu_xAl_yO system was obtained, and the electronic structure and optical properties of pure ZnO and ZnO codoped with Cu-Al were calculated by the first-principles. The results show that the light absorption of the above-mentioned doped systems is red-shifted in the low energy zone, and the system is degenerate semiconductor. For different purposes of ZnO, the optical absorption or light transmission of the system in visible light can be improved by controlling Cu/Al doping ratio. In visible light, the light absorption of Zn_{0.812 5}Cu_0.125Al_{0.062 5}O system is the strongest, which can be used to make photoelectrode materials for solar panels. The high transmittance of the Zn_{0.812 5}Cu_{0.062 5}Al_0.125O system can be used to make high transmittance ZnO semiconductor thin films.