Liu Bo, Giordano Fabrizio, Pei Kai, Decoppet Jean-David, Zhu Wei-Hong, Zakeeruddin Shaik M, Grätzel Michael
Shanghai Key Laboratory of Functional Materials Chemistry, Key Laboratory for Advanced Materials and Institute of Fine Chemicals, East China University of Science & Technology, 130 Meilong Road, Shanghai 200237 (P. R. China).
College of Chemistry and Material Science, Hebei Normal University, No. 20, East Road of Nan ErHuan, Shijiazhuang 050024 (P. R. China).
Chemistry. 2015 Dec 14;21(51):18654-61. doi: 10.1002/chem.201503514. Epub 2015 Nov 9.
Due to the ease of tuning its redox potential, the cobalt-based redox couple has been extensively applied for highly efficient dye-sensitized solar cells (DSSCs) with extraordinarily high photovoltages. However, a cobalt electrolyte needs particular structural changes in the organic dye components to obtain such high photovoltages. To achieve high device performance, specific requirements in the molecular tailoring of organic sensitizers still need to be met. Besides the need for large electron donors, studies of the auxiliary acceptor segment of donor-acceptor-π-acceptor (D-A-π-A) organic sensitizers are still rare in molecular optimization in the context of cobalt electrolytes. In this work, two novel organic D-A-π-A-type sensitizers (IQ13 and IQ17) have been developed and exploited in cobalt- and iodine-based redox electrolyte DSSCs, specifically to provide insight into the effect of π-bridge modification in different electrolytes. The investigation has been focused on the additional electron-withdrawing acceptor capability with grafted long alkoxy chains. Optoelectronic transient measurements have indicated that IQ17 containing a pyrido[3,4-b]pyrazine moiety bearing long alkoxyphenyl chains is more suitable for application in cobalt-based DSSCs.
由于其氧化还原电位易于调节，钴基氧化还原对已被广泛应用于具有极高光电压的高效染料敏化太阳能电池（DSSC）。然而，钴电解质需要有机染料成分有特定的结构变化才能获得如此高的光电压。为了实现高器件性能，有机敏化剂的分子剪裁仍需满足特定要求。除了需要大的电子供体外，在钴电解质的背景下，供体-受体-π-受体（D-A-π-A）有机敏化剂的辅助受体部分在分子优化方面的研究仍然很少。在这项工作中，已经开发并在基于钴和碘的氧化还原电解质DSSC中应用了两种新型有机D-A-π-A型敏化剂（IQ13和IQ17），特别是为了深入了解不同电解质中π桥修饰的影响。研究集中在接枝长烷氧基链的额外吸电子受体能力上。光电瞬态测量表明，含有带有长烷氧基苯基链的吡啶并[3,4-b]吡嗪部分的IQ17更适合应用于基于钴的DSSC。
