Dye-sensitized solar cells based on nanoparticle-decorated ZnO/SnO2 core/shell nanoneedle arrays

作者：Zhou, Yang; Xia, Chao; Hu, Xiaoyan; Huang, Wei; Aref, A. A.; Wang, Bixiao; Liu, Zhengjing; Sun, Yongming; Zhou, Wei; Tang, Yiwen^*

来源：Applied Surface Science, 2014, 292: 111-116.

DOI：10.1016/j.apsusc.2013.11.095

• ZnO/SnO2 Core-shell nanoneedle
• F-
• High conversion efficiency
• A larger surface area

Novel ZnO/SnO2 core-shell nanoneedle arrays were developed with a two-step synthesis strategy. The strategy combines two processes: a hydrothermal synthesis of a ZnO nanoneedle array and a coating of a SnO2 layer on the surface of the ZnO nanoneedle. The addition of F- to the hydrothermal reaction solution played an important role in the formation of the ZnO nanoneedle array. The ZnO/SnO2 core-shell structure was successfully achieved after depositing a thin SnO2 layer on the ZnO nanoneedle by dip-coating. Dye-sensitized solar cells (DSSCs) based on ZnO/SnO2 core-shell nanoneedle arrays were assembled, and a high conversion efficiency (eta) of around 4.71% was obtained at 0.9 suns. This can be attributed to the advantages of the core-shell structure. On the one hand, it affords a larger surface area for a more dye loading and light harvesting, which result in enhancing the photocurrent of the DSSC. On the other hand, the core/shell structure passivates nanoneedle surface defects for suppressing the recombination, which leads to the increase of the open-circuit voltage. Accordingly, the enhanced photocurrent and open-circuit voltage have led to a prominent increase in the photovoltaic efficiency of around 4.71%, which is much higher than that of an ordinary ZnO nanoneedle array-based DSSC.

• 出版日期2014-2-15
• 单位华中师范大学