New Ruthenium Sensitizers Featuring Bulky Ancillary Ligands Combined with a Dual Functioned Coadsorbent for High Efficiency Dye-Sensitized Solar Cells

作者：Shi Yongbo; Liang Mao^*; Wang Lina; Han Hongyu; You Lingshan; Sun Zhe; Xue Song

来源：ACS Applied Materials & Interfaces, 2013, 5(1): 144-153.

DOI：10.1021/am302318z

• ruthenium complexes
• extinction coefficients
• ancillary ligand
• charge recombination
• coadsorbent
• sequential adsorption

Two ruthenium complexes featuring bulky ancillary ligands, XS48 and XS49, were synthesized and studied as dyes in dye-sensitized solar cells (DSCs). Both dyes exhibit higher solar-to-electrical energy conversion efficiency when compared to a commonly used N3 sensitizer under the same conditions. To examine the influence of the bulky ancillary ligands and alleviate the electron recombination in cells, we have developed a dual functioned truxene-based coadsorbent (MXD1) as an alternative candidate to chenodeoxycholic acid (CDCA). This I coadsorbent not only effectively shields the back electron transfer from the TiO2 to I-3(-) ions but also enhances the light harvesting ability in the short wavelength regions. The photovoltaic performance of XS48-sensitized DSC was independent of the coadsorbents, while XS49 with large bulky ancillary ligand presented better performance when coadsorbent was employed. Interestingly, the simultaneous adsorption-to-sequential adsorption of XS48/49 and MXD1 has caused a notably improved photovoltage, which can be primarily ascribed to the enhanced dye adsorption and retardation of charge recombination. These results not only provide a new vision on how ancillary ligands affect the performance of ruthenium complexes but also open up a new way to achieve further efficiency enhancement of ruthenium complexes.

• 出版日期2013-1-9
• 单位天津理工大学