为了使新型薄膜太阳能电池结构中的ZnO纳米柱阵列能高效捕获光子与收集载流子, 研究了提高ZnO纳米柱阵列的电导率和操控其光学性质的方法。使用电沉积方法在溶解有Zn(NO3)2、NH4NO3、Al(NO3)3的水溶液中制备了Al掺杂的ZnO纳米柱阵列。实验显示, 通过控制电解液中NH4NO3的浓度可操控所制备的ZnO纳米柱阵列的直径、密度和间距。电解液中NH4NO3浓度的增加会导致所制备的ZnO纳米柱中Al/Zn的质量比显著增大,通过控制NH4NO3在溶液中的添加即可在3.72~3.76 eV内调控所制备的ZnO纳米柱的光学带隙宽度, 并能够对其透射、反射、吸收等光学性质进行操控。另外, 在电解液中添加NH4NO3, 可在377~449 meV内调控所制备的ZnO纳米柱的斯托克斯位移, 从而操控ZnO纳米柱内部的非辐射复合。因此, 在电解液中使用NH4NO3增强所制备的ZnO纳米柱中Al的含量, 不仅可使ZnO纳米柱在保持高迁移率的条件下具有高的电导率, 还可实现对光学性质的操控。

To allow the ZnO nanorod arrays in new thin film solar cells to capture photons and to collect carriers effectively, a method to improve the conductivity of the ZnO nanorods and to control their optical properties was researched. Al-doped ZnO nanorod arrays were prepared by electrodeposition in aqueous solutions with Zn(NO3)2, NH4NO3 and Al(NO3)3. The experimental results indicate that the properties of ZnO nanorods such as the diameter, density and distance could be adjusted by controlling the NH4NO3 concentration in the electrolyte. The use of NH4NO3 in the solution leads to an increase of the Al/Zn weight ratio in the ZnO nanorods. By controlling the NH4NO3 concentration in the solution, the optical band gap of ZnO nanorod can be adjusted between 3.72—3.76 eV, and the optical properties of the nanorod such as the transmission, reflection and absorption can be controlled. The Stokes shift of the Al-doped ZnO nanorods was in the range of 377—449 meV, indicating the nonradiative recombination in the nanorods. Therefore the use of NH4NO3 in the electrolytes has successed in enhancing the Al doping in the ZnO nanorods and controlling their optical properties.