Donor design and modification strategies of metal-free sensitizers for highly-efficient n-type dye-sensitized solar cells

Abstract

Dye-sensitized solar cells (DSSCs) cannot be developed without the research on sensitizers. As the key of light harvesting and electron generation, thousands of sensitizers have been designed for the application in DSSC devices. Among them, organic sensitizers have drawn a lot of attention because of the flexible molecular design, easy synthesis and good photovoltaic performance. Recently, new record photovoltaic conversion efficiencies of 11.5% for DSSCs with iodide electrolyte and 14.3% for DSSCs with cobalt electrolyte and co-sensitization have been achieved with organic sensitizers. Here we focus on the donor design and modification of organic sensitizers. Several useful strategies and corresponding typical examples are presented.

Keywords

donors / organic sensitizers / dye-sensitized solar cells (DSSCs)

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Acknowledgements

For financial support of this research, we thank the Science Fund for Creative Research Groups (21421004), the National Basic Research Program of China (973 Program) (No. 2013CB733700), and the National Natural Science Foundation of China (Grant Nos. 21172073, 21372082, 21572062 and 91233207). J.-L. Hua appreciates Prof. H. Tian very much for his helpful discussion and valuable comments.

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2014 Higher Education Press and Springer-Verlag Berlin Heidelberg