基于偶极矩调控和侧链修饰的新型聚合物材料的设计、制备与光电性能研究

项目名称： 基于偶极矩调控和侧链修饰的新型聚合物材料的设计、制备与光电性能研究

项目编号： No.21304018

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 孙莹

作者单位： 东南大学

项目金额： 25万元

中文摘要： 聚合物太阳能电池因具有工艺简单、成本低、重量轻、可制成柔性器件等突出优点，具有显著的应用前景。 然而由于聚合物低的介电常数和高的激子束缚能，电荷分离困难，复合现象严重，限制了光电性能的提高。本项目通过将分子偶极矩调控和侧链修饰协同起来，对聚合物分子结构进行设计优化。采用主链给体-侧链受体的共轭聚合物结构，结合理论模拟计算，一方面对其分子偶极矩进行调控，并利用给受体的推拉电子体系,以减少电子和空穴之间的束缚力，使得光激发后电子在侧链聚集，促进电荷的分离，减少电荷复合；另一方面开创性的在侧链接枝萘基团，以改进与富勒烯衍生物的相容性，诱导富勒烯衍生物在侧链处的聚集，促使侧链处富集的电子得以迅速转移和混合膜中互穿网络结构的形成。制备一系列新型聚合物材料，系统的研究分子结构改变对电荷分离、电荷传输、电荷复合、本体异质结混合膜形貌、光电性能等的影响，并探索其内在机制和影响规律。

中文关键词： 共轭聚合物；侧链；自组装；聚集体；光电性能

英文摘要： Polymer solar cells have showed a broad application prospect because of their advantages such as low cost, light weight, flexibility and ease of large-area processing. However, the relatively low dielectric constant and high exciton binding energy (0.3-0.5 eV) in conjugated polymers primarily limit the effective charge separation and lead to charge recombination, which hence can reduce the efficiency of polymer solar cell. In this project, we present a new polymer molecule design by combining the manipulation of dipole moment and side chain modification together. First, a side-chain donor-acceptor conjugated polymer structure is employed with the main chain constructed by donor moieties and the acceptor units conjugatedly pended onto the donor unit in the side chain. On the basis of density functional theory calculation, the dipole moment of polymer is optimized by tuning the side chain structure of polymer to promote the electron to be concentrated in the side chain and hence facilitate charge separation as well as reduce charge recombination. In addition, naphthalene group is introduced to the side chain to improve the miscibility with fullerene derivatives and induce the aggregation of fullerene derivatives in the side chain units, which will provide the fast charge transfer and formation of nanoscale biconti

英文关键词： conjugated polymer；side chains；self assemble；aggregation；photovoltaic