Three metal-free bithiazole organic dyes (BTT-I–III) based on D–A-π-A building blocks were designed and synthesized for dye-sensitized solar cells (DSSCs) to study the influence of different electron donors on photovoltaic properties, in which the electron donors of BTT-I–III were carbazole, triphenylamine and indoline moieties, respectively. The UV/Vis absorption spectra of BTT-III containing indoline as electron-donor displayed red-shifted absorption compared to the other two dyes with an onset close to 700 nm. The incident photon-to-current conversion efficiency (IPCE) spectra of BTT-III showed a wide region and kept a value higher than 10–15% during 580–650 nm. Electrochemical measurement data indicated that the HOMO and LUMO energy levels could be tuned through introducing different electron-donors in the dye molecule. It was found that the overall conversion efficiency of indoline donor based dye BTT-III showed the highest efficiency of 7.86% under AM 1.5 irradiation (100 mW cm−2). The electron lifetime calculated from electrochemical impedance spectroscopy (EIS) measurement demonstrated the reduced charge recombination and the higher open-circuit voltage.
                                    基于D-A-π-A结构单元的三种不含
金属的联
噻唑有机
染料(B
TT-I-III)被设计并合成用于
染料敏化太阳能电池(DSSC),以研究不同电子供体对光伏特性的影响,其中B
TT-I-III的电子供体分别是
咔唑、
三苯胺和
吲哚啉部分。与另外两种
染料相比,含有
吲哚啉作为电子供体的B
TT-III的紫外/可见光吸收光谱显示吸收红移,起始波长接近700 nm。B
TT-III的入射光子到电流的转换效率(IPCE)光谱显示在580-650 nm范围内有一个宽区域,并保持高于10-15%的值。电
化学测量数据表明,可以通过在
染料分子中引入不同的电子供体来调节HOMO和LUMO能级。研究发现,在
AM 1.5辐照(100 mW cm-2)下,基于
吲哚啉供体的
染料B
TT-III的总转换效率最高,为7.86%。从电
化学阻抗谱(EIS)测量计算的电子寿命表明,电荷复合减少,开路电压更高。