Photovoltaic performance improvement via designing nanorod parameter in composite-structure solar cells

Abstract In this work, the optical characteristics of electrodeposited Cu2O films was studied, and the depth of photogenerated carriers in Cu2O films was obtained. In order to improve the collection depth of the photogenerated carrier in ZnO/Cu2O solar cells, ZnO nanorod array were employed to construct composite-structure solar cells. The influence of the ZnO nanorod arrays on short-circuit current and open circuit voltage was systematically analyzed in the nanorod cells. For optimizing device performance, ordered ZnO nanorod arrays that incorporated design spacing that matched the carrier diffusion length of the absorption layer were used. Analyses of the photovoltaic properties revealed that ordered nanorod arrays with a proper spacing could improve carrier generation efficiency in high-efficient collection regions of the carriers. These observations indicate that nanorod spacing is an important variable in the construction of high-efficient nanorod-based solar cells.