A series of organic dyes containing a phenothiazine central unit were synthesized and were used effectively in the fabrication of dye-sensitized solar cells (DSSCs). A cyanoacrylate moiety was added at the C(3) position of the phenothiazine as an electron acceptor, and a triarylamine moiety was attached at the C(7) position as an electron donor. The DSSCs made with these dyes displayed remarkable quantum efficiency, ranging from 4.2–6.2% under an AM 1.5 solar condition (100 mW cm−2). A variety of substituents, i.e., methyl, hexyl and triphenylamino groups, were added at the N(10) of phenothiazine in order to optimize the incident photon-to-current conversion efficiency. Along the main chromophore a thiophenylene group was inserted at different positions to examine its influence on the properties of devices. The best performance was found in compound NSPt-C6, in which a hexyl group was attached at the N(10) of phenothiazine and a thiophenylene at the C(7) position. It displayed a short-circuit current (Jsc) of 14.42 mA cm−2, an open-circuit voltage (Voc) of 0.69 V, and a fill factor (ff) of 0.63, corresponding to an overall conversion efficiency of 6.22%. Their photophysical properties were analyzed with the aid of a time-dependent density functional theory (TDDFT) model with the B3LYP functional. Their photovoltaic behavior was further elucidated by the electrochemical impedance spectroscopy.
合成了一系列含有苯
噻嗪中心单元的有机
染料,并有效地用于
染料敏化太阳能电池(DSSCs)的制造。在苯
噻嗪的C(3)位点添加了一种
氰基丙烯酸酯部分作为电子受体,同时在C(7)位点连接了
三芳胺部分作为电子给体。使用这些
染料制作的DSSC在
AM 1.5太阳条件下(100 mW cm−2)显示出显著的量子效率,范围为4.2%至6.2%。在苯
噻嗪的N(10)位点添加了多种取代基,如甲基、己基和
三苯胺基,以优化入射光子到电流的转换效率。在主要
染料上还在不同位置插入了
噻吩苯基,以研究其对器件性能的影响。最佳表现发现于化合物N
SPt-C6,其中在苯
噻嗪的N(10)位点连接了己基,并在C(7)位点连接了
噻吩苯基。它显示出短路电流(Jsc)为14.42 mA cm−2,开路电压(Voc)为0.69 V,填充因子(ff)为0.63,相应的整体转换效率为6.22%。借助时间相关密度泛函理论(TDDFT)模型与B3LYP泛函分析了它们的光物理性质。通过电
化学阻抗谱进一步阐明了它们的光伏行为。