Seo Kang Deuk, Choi In Tack, Kim Hwan Kyu
Global GET-Future Laboratory, Department of Advanced Materials Chemistry, Korea University, Sejong 339-700 (Korea), Fax: (+82)41-867-5396.
Chemistry. 2015 Oct 12;21(42):14804-11. doi: 10.1002/chem.201502289. Epub 2015 Sep 1.
Seven SGT organics dyes, containing bis-dimethylfluoreneyl amino groups with a dialkoxyphenyl unit as an electron donor and a cyanoacrylic acid group as an anchoring group, connected with oligothiophenes, fused thiophenes and benzothiadiazoles as π-bridges, were designed and synthesised for applications in dye-sensitised solar cells (DSSCs). The photovoltaic performance of DSSCs based on organic dyes with oligothiophenes depends on the molecular structure of the dyes, in terms of the length change of the π-bridging units. The best performance was found with a π-bridge length of about 6 Å. To further enhance the photovoltaic performance associated with this concept, cyclopenta[1,2-b:5,4-b']dithiophene (CPDT) and benzothiadiazole were introduced into the π-bridge unit. As a result, the DSSC based on the organic dye containing the CPDT moiety showed the best photovoltaic performance with a short-circuit photocurrent density (Jsc ) of 14.1 mA cm(-2) , an open-circuit voltage (Voc ) of 0.84 V and a fill factor (FF) of 0.72, corresponding to an overall conversion efficiency (η) of 8.61 % under standard AM 1.5 irradiation.
设计并合成了七种SGT有机染料，它们含有双二甲基芴基氨基，以二烷氧基苯基单元作为电子供体，氰基丙烯酸基团作为锚定基团，并与低聚噻吩、稠合噻吩和苯并噻二唑作为π桥相连，用于染料敏化太阳能电池（DSSC）。基于含有低聚噻吩的有机染料的DSSC的光伏性能取决于染料的分子结构，具体表现为π桥连单元长度的变化。发现当π桥长度约为6 Å时性能最佳。为了进一步提高与该概念相关的光伏性能，将环戊[1,2-b:5,4-b']二噻吩（CPDT）和苯并噻二唑引入π桥单元。结果，基于含有CPDT部分的有机染料的DSSC表现出最佳的光伏性能，在标准AM 1.5光照下，短路光电流密度（Jsc）为14.1 mA cm(-2)，开路电压（Voc）为0.84 V，填充因子（FF）为0.72，对应于总转换效率（η）为8.61%。
