State Key Laboratory of Electronic Thin Films and Integrated Devices, School of Microelectronics and Solid-State Electronics, University of Electronic Science and Technology of China , Chengdu 610054, China.
School of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China.
ACS Appl Mater Interfaces. 2017 Aug 2;9(30):25225-25231. doi: 10.1021/acsami.7b04233. Epub 2017 Jul 24.
Rhodanine-3-acetic acid is a very important and common electron acceptor of organic dye for dye-sensitized solar cells (DSSCs). However, the photovoltaic performances of organic dyes with rhodanine-3-acetic acid are relatively poor in the great majority of cases due to its nonconjugated structure between rhodanine ring and carboxyl anchoring group. Herein, a rhodanine derivative with conjugated structure between rhodanine ring and anchoring group is first employed as electron acceptor for TiO-based DSSCs. Organic dye with this conjugated electron acceptor can not only maintain wide absorption spectrum but also greatly improve the electronic structure and adsorption geometry on TiO, which significantly enhances the electron injection and slows the charge recombination. So the power conversion efficiency of DSSC based on organic dye CRD-I with this conjugated electron acceptor is increased by 2 times as compared with DSSC based on organic dye RD-I with nonconjugated rhodanine-3-acetic acid. Moreover, it is also found that CRD-I is superior to RD-I with respect to DSSC stability and binding ability to TiO. This work unambiguously demonstrates that the conjugated rhodanine derivative is a highly promising electron acceptor and provides a new strategy for high-efficiency rhodanine-based organic dyes in DSSCs.
硫代雷琐酸-3-乙酸是一种非常重要且常见的有机染料敏化太阳能电池（DSSC）电子受体。然而，由于硫代雷琐酸环和羧酸锚定基团之间的非共轭结构，大多数情况下，带有硫代雷琐酸-3-乙酸的有机染料的光伏性能相对较差。在此，首次将硫代雷琐酸环和锚定基团之间具有共轭结构的硫代雷琐酸衍生物用作基于 TiO2 的 DSSC 的电子受体。带有这种共轭电子受体的有机染料不仅可以保持宽的吸收光谱，而且可以极大地改善 TiO2 上的电子结构和吸附几何形状，从而显著增强电子注入并减缓电荷复合。因此，与基于非共轭硫代雷琐酸-3-乙酸的有机染料 RD-I 的 DSSC 相比，基于具有共轭电子受体的有机染料 CRD-I 的 DSSC 的功率转换效率提高了 2 倍。此外，还发现 CRD-I 在 DSSC 稳定性和与 TiO2 的结合能力方面优于 RD-I。这项工作明确表明，共轭硫代雷琐酸衍生物是一种很有前途的电子受体，并为基于硫代雷琐酸的高效有机染料在 DSSC 中的应用提供了新的策略。
