Highly efficient quantum-dot-sensitized solar cells with composite semiconductor of ZnO nanorod and oxide inverse opal in photoanode

Photoelectric conversion is realized by a series of processes in quantum-dot-sensitized solar cells (QDSSCs), including light capture, photoelectron generation, and electron transmission. In addition to obtaining photoelectrons, the photoanode provides a channel for electron transmission. Therefore, the photoanode plays important roles in improving the performances of QDSSCs. This paper presents the fabrication of a novel photoanode based on a semiconductor composite of ZnO nanorods and TiO2/ZnO inverse opal. QDSSCs with composite semiconductors of ZnO nanorods and oxide inverse opal in the photoanode were demonstrated to facilitate better charge transfer and reaction rates at the interface and obtain higher photocurrents and power conversion efficiencies than those of QDSSCs with pure inverse opal photoanodes. Using a CdS/CdSe co sensitizer in the QDSSCs, a maximum cell efficiency of 8.18% was obtained, and it was further improved to 11.24% after interface modification with NH4F and ZnS.

Automated summary

This paper presents the fabrication of a novel photoanode based on a semiconductor composite and tests its performance in QDSSCs. The experimental results show that the new photoanode exhibits better charge transfer and reaction rates, as well as higher photocurrents and power conversion efficiencies. After interface modification, the cell efficiency is further improved.