近红外染料衍生的可溶性星形共轭大分子类电子受体材料

The development of non-fullerene type organic electron acceptors has not advanced remarkably to this date, which has become one of the major bottlenecks that prevent the significant increase in the efficiency of organic BHJ solar cells. Currently, the critical problems of non-fullerene acceptors represented by perylenebisimide derivatives include the poor absorption in long wavelength region of solar spectrum and the excessive aggregation induced damage of film morphology. To overcome these problems, this project will develop four series of soluble star-shaped conjugated macromolecules based on near infrared dyes. These macromolecules are composed of four perylenebisimide units as branches to facilitate electron transporting, and of one near infrared dye (e.g. aza-BODIPY, squaraine) as the core which provides the NIR absorption. In addition, owing to the twisted non-planar structures of the NIR core, the excessive aggregations of the conjugated macromolecules will be inhibited, which increases their solubility and is favorable for them to form high quality films when blended with the organic electron donors. The novel electron acceptors developed in this project will be competitive alternatives to the fullerene derivatives and will be helpful to increase the solar cells efficiency. This research integrates the principles and skills of dyes chemistry and organic electronics and will promote the cross-integrations and advances of the two important disciplines.

非富勒烯类有机电子受体材料的研发至今未取得重大进展，成为制约有机薄膜太阳能电池效率显著提高的一个主要瓶颈。目前以苝酰亚胺为代表的非富勒烯类受体材料存在着对太阳光谱中长波波段响应能力弱和过度聚集破坏薄膜形貌的关键性问题。为此，本项目开发四个系列在近红外区域有强烈光吸收性质的可溶性星形共轭大分子。其拥有四个苝酰亚胺作为星形共轭体系的枝结构单元以促进电子传输，并以aza-BODIPY 、方酸菁等高性能近红外染料为中心核结构单元以延展吸收光谱；而且，由于核的局部扭曲非平面性，抑制星形大分子间过度π-π 堆积，使材料具备适中的溶解度，有利于其与电子供体共混形成高质量薄膜活性层。应用本项目开发的新型电子受体材料，有望能获得与使用富勒烯衍生物类相近或更高的有机薄膜体相异质结太阳能电池器件效率。本项目研究思路集成了染料化学和有机电子学的原理与技术，必将促进二者的交叉融合和进一步发展。

非富勒烯类有机电子受体材料的研发至今未取得重大进展，成为制约有机薄膜太阳能电池效率显著提高的一个主要瓶颈。目前以苝酰亚胺为代表的非富勒烯类受体材料存在着对太阳光谱中长波波段响应能力弱和过度聚集破坏薄膜形貌的关键性问题。为此，本项目开发多个系列在近红外区域有强烈光吸收性质的可溶性星形共轭大分子，也就是苝酰亚胺多倍体。其拥有多个苝酰亚胺作为星形共轭体系的枝结构单元以促进电子传输，并且延展吸收光谱；此外，设计大分子共轭骨架为局部扭曲非平面性，抑制星形大分子间过度π-π 堆积，使材料具备适中的溶解度，有利于其与电子供体共混形成高质量薄膜活性层。应用本项目开发的新型电子受体材料，获得比使用富勒烯衍生物类更高的有机薄膜体相异质结太阳能电池器件效率。其中最高的电池光电转换效率达到了8.3%。完成本项目在国际学术期刊上发表论文24篇。本项目研究思路集成了染料化学和有机电子学的原理与技术，必将促进二者的交叉融合和进一步发展。