Zhou Haoran, Ji Jung-Min, Kim Min Su, Kim Hwan Kyu
Global GET-Future Lab. & Department of Advanced Materials Chemistry, Korea University, 2511 Sejong-ro, Sejong 339-700, Korea.
Nanomaterials (Basel). 2018 Dec 11;8(12):1030. doi: 10.3390/nano8121030.
The rational design of porphyrin sensitizers is always crucial for dye-sensitized solar cells (DSSCs), since the change of only a single atom can have a significant influence on the photovoltaic performance. We incorporated the pyridothiadiazole group, as a stronger electron-withdrawing group, into the commonly well-established skeleton of D-porphyrin-triple bond-acceptor sensitizers by a single atom change for a well-known strong electron-withdrawing benzothiadiazole (BTD) unit as an auxiliary acceptor. The impact of the pyridothiadiazole group on the optical; electrochemical; and photovoltaic properties of D⁻π⁻A porphyrin sensitizers was investigated with comparison for a benzothiadiazole-substituted porphyrin. The pyridothiadiazole-substituted porphyrin dye was red-shifted so that the absorption range might be expected to achieve higher light harvest efficiency (LHE) than the porphyrin. However, all the devices were fabricated by utilizing and , evaluated and found to achieve a cell efficiency of 10.3% for -based DSSC but 4.2% for -based DSSC under standard global AM 1.5G solar light conditions. The main reason is the lower charge collection efficiency of -based DSSC than -based DSSC, which can be attributed to the tilted dye adsorption mode on the TiO₂ photoanode. This may allow for faster charge recombination, which eventually leads to lower and power conversion efficiency (PCE).
对于染料敏化太阳能电池（DSSC）而言，卟啉敏化剂的合理设计始终至关重要，因为仅一个原子的变化就可能对光伏性能产生重大影响。我们通过将一个原子替换为作为辅助受体的著名强吸电子苯并噻二唑（BTD）单元，将吡啶并噻二唑基团作为更强的吸电子基团引入到常用的D-卟啉-三键-受体敏化剂骨架中。通过与苯并噻二唑取代的卟啉进行比较，研究了吡啶并噻二唑基团对D-π-A卟啉敏化剂的光学、电化学和光伏性能的影响。吡啶并噻二唑取代的卟啉染料发生了红移，因此预计其吸收范围可能比卟啉实现更高的光捕获效率（LHE）。然而，所有器件均利用[具体物质1]和[具体物质2]制备，经过评估发现在标准全球AM 1.5G太阳光条件下，基于[物质1]的DSSC的电池效率为10.3%，而基于[物质2]的DSSC的电池效率为4.2%。主要原因是基于[物质2]的DSSC的电荷收集效率低于基于[物质1]的DSSC，这可归因于染料在TiO₂光阳极上的倾斜吸附模式。这可能会导致更快的电荷复合，最终导致更低的[具体性能指标]和功率转换效率（PCE）。
