Department of Molecular Engineering, Graduate School of Engineering, Kyoto University, Nishikyo-ku, Kyoto 615-8510, Japan.
ChemSusChem. 2013 Mar;6(3):508-17. doi: 10.1002/cssc.201200869. Epub 2013 Feb 11.
We have prepared a push-pull porphyrin with an electron-donating triarylamino group at the β,β'-edge through a fused imidazole group and an electron-withdrawing carboxyquinoxalino anchoring group at the opposite β,β'-edge (ZnPQI) and evaluated the effects of the push-pull structure of ZnPQI on optical, electrochemical, and photovoltaic properties. ZnPQI showed red-shifted Soret and Q bands relative to a reference porphyrin with only an electron-withdrawing group (ZnPQ), thus demonstrating the improved light-harvesting property of ZnPQI. The optical HOMO-LUMO gap was consistent with that estimated by DFT calculations. The ZnPQI-sensitized solar cell exhibited a relatively high power conversion efficiency (η) of 6.8 %, which is larger than that of the ZnPQ-sensitized solar cell (η=6.3 %) under optimized conditions. The short-circuit current and fill factor of the ZnPQI-sensitized solar cell are larger than those of the ZnPQ-sensitized solar cell, whereas the open circuit potential of the ZnPQI-sensitized cell is smaller than that of the ZnPQ-sensitized cell, leading to an overall improved cell performance of ZnPQI. Such fundamental information provides a new tool for the rational molecular design of highly efficient dye-sensitized solar cells based on push-pull porphyrins.
我们通过融合的咪唑基团在β,β'-边缘制备了一个具有供电子三芳基氨基基团的推挽卟啉，并在相反的β,β'-边缘具有吸电子羧基喹喔啉锚定基团（ZnPQI），并评估了 ZnPQI 的推挽结构对光学、电化学和光伏性能的影响。ZnPQI 相对于仅具有吸电子基团的参比卟啉（ZnPQ）显示出 Soret 和 Q 带的红移，从而证明了 ZnPQI 改善了光捕获性能。光学 HOMO-LUMO 带隙与通过 DFT 计算估计的值一致。ZnPQI 敏化太阳能电池在优化条件下表现出相对较高的功率转换效率（η）为 6.8%，高于 ZnPQ 敏化太阳能电池（η=6.3%）。ZnPQI 敏化太阳能电池的短路电流和填充因子大于 ZnPQ 敏化太阳能电池，而 ZnPQI 敏化电池的开路电压小于 ZnPQ 敏化电池，导致 ZnPQI 的整体电池性能得到改善。这种基本信息为基于推挽卟啉的高效染料敏化太阳能电池的合理分子设计提供了新工具。
