1,4-[60]富勒烯基聚合物太阳能电池受体材料的设计合成及光伏性质研究

Polymer solar cell（PSC） has attracted tremendous attention for its lowcost, light weight and flexible manufacturing. 1,2-C60-based acceptors which are represented by PCBM have been widely studied and applied in PSCs. At present, 1,4-C60-based acceptors have limitations including the structural onefold, multi-step synthetic procedure, and high cost. Most importantly, the maximum PCEs of PSCs constructed by 1,4-C60-based acceptors are considerably lower than conventional silicon solar cells. One of the main challenges in this field is to design and synthesize of novel 1,4-C60-based acceptors with excellent comprehensive performance through molecular level operation. This project aim at high efficiency synthesis series of unsymmetric 1,4-C60-based acceptors by developing base-promoted "one-pot" three-component coupling reactions of arenes (such as carbazols, triphenylamines, phenols), C60 and haloalkanes. Our molecular design and research goal are as following: (1) Construction of 1,4-unsymmetric difunctionalized C60 skeleton to increase and extend light absorption. (2) Utilizing electron-rich arenes and electron-donating functional group to raise the LUMO-level of these 1,4-C60-based acceptors. (3) Introduction various functional regulatory groups by different haloalkanes to increase the solubility of acceptors and tune the morphology of the bulk heterojunction(BHJ). The project will explore the relationship between various modified units and absorption enhancement, LUMO-level raise by UV-Vis absorption spectrum and cyclic voltammetry. We will select several 1,4-C60 acceptors with nice performance to construct P3HT:1,4-C60 PSC. On the basis of above study of the P3HT:1,4-C60 photovoltaic properties, we will establish the mechanism between the molecules and photovoltaic properties, further optimize the structure to enhance performance, and develop a 1,4-C60-based acceptor with excellent comprehensive performance.

聚合物太阳能电池具有成本低、重量轻、可制备成柔性器件等优点，近年来备受关注。虽然以PCBM为代表的1,2-加成的C60受体材料得到广泛的研究与应用，但目前已报道的1,4-加成的C60受体材料结构类型单一、合成步骤复杂、成本昂贵，其构筑的光伏器件能量转换效率偏低。本项目拟发展碱促进的芳烃（咔唑、三苯胺、苯酚）与C60、卤代烃的三组分“一锅法”偶联反应，简便高效制备系列不对称的1,4-C60基受体材料。分子设计策略和核心研究思路是：（1）构筑1,4-不对称双官能化C60修饰骨架以拓宽和增强材料分子的光吸收范围和强度。（2）发挥富电子芳烃和供电子取代基的协同作用提高材料LUMO轨道能级。（3）选择引入不同功能调控基团以提高材料的溶解度及其与给体分子构筑的本体异质结性能。探明构效关系，筛选受体材料，组装光伏器件，优化结构，力争研发出综合光伏性能优秀的1,4-C60基受体材料。

本项目利用本课题组开发的酚与C60和卤代烃的“一锅法”多米诺偶联反应，合成了一系列1，4-不对称富勒烯基电子传输层材料分子。通过组装光伏器件，筛选出了一种综合光伏性能优秀的C60基电子传输层材料，与传统的商用的PCBM材料相比，该材料分子具有性能优越，制备简便，成本低廉的特点。发展了一种富勒烯衍生化的新策略-“极性逆转接力”策略，通过这一策略可以实现C60的“一锅法”两次极性反转串联，利用这一策略可以简捷高效合成种类丰富的富勒吲哚衍生物。这些C60衍生物将可用作有机功能材料如太阳能电池受体和电子传输层材料。