基于三元共混体系的小分子有机太阳能电池性能研究

项目名称： 基于三元共混体系的小分子有机太阳能电池性能研究

项目编号： No.51473009

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 一般工业技术

项目作者： 孙艳明

作者单位： 北京航空航天大学

项目金额： 85万元

中文摘要： 由于自身的特性，有机半导体材料的光谱吸收范围比较窄，限制了有机太阳能电池效率的进一步提高。通过分子设计与合成，可以将材料的光谱响应范围拓宽至近红外区域，但是基于这类材料的太阳能电池往往具有较低的开路电压，导致器件整体性能不高。叠层结构可以增加活性层对太阳光的吸收，提高电池的转换效率。但是复杂的器件结构和制备工艺，给叠层太阳能电池的制备带来很大困难。三元共混体系有机太阳能电池,通过利用两种不同带隙宽度的给体材料（分别为主体给体材料和近红外敏化染料材料），大幅度增加了其对太阳光的利用率。此外，这种器件结构比较简单，制备相对容易。由于对该类电池的工作原理认识不深，目前它的转换效率还比较低。本项目拟将选择一些高性能可溶液法加工的小分子材料，来制备三元共混体系小分子有机太阳能电池。通过对活性层聚集态结构和性能关系以及激子的产生和分离，载流子传输和复合等基础问题的研究，加深对这类电池工作机理的认识。

中文关键词： 有机太阳能电池；有机小分子；三元共混体系；溶液加工；能量转换效率

英文摘要： Owing to the molecular excitonic nature of the primary excitation, the absorption window of organic semiconductors is relatively narrow, which hinders the improvement of the power conversion efficiency (PCE) in organic solar cells. In order to overcome the absorption limitation and improve the light harvesting, novel low bandgap organic semiconductors would extend light absorption to near infrared (IR) region. However, solar cells based on these materials tend to have low open-circuit voltage. As a result, the overall PCEs of solar cells are low. Tandem device architectures have been demonstrated as a useful approach towards fabrication of high-efficiency solar cells, where two subcells are stacked in series and the individual photoactive layers have complementary absorption spectra. However, the complicated multilayer structure raises serious technical challenges in device fabrication. An elegant alternative strategy was realized to extend the spectral sensitivity of organic semiconductors into the near IR region by adding an IR sensitizer into the blend solutions of another wide-bandgap donor as the host donor and fullerene derivatives, the so-called organic ternary solar cells. This device is simple and can be easily fabricated. However, the power conversion efficiency is low due to a lack of understanding of the working principles of ternary organic solar cells. In this project, we will select several high-performance solution-processed small molecules and then fabricated ternary blend based small molecule solar cells. We will focus on the study of charge transfer,transport,recombination mechanisms and structure-property relationships of donors and acceptors in the ternary blend to gain deeper insight into the working principles of ternary organic solar cells.

英文关键词： Organic solar cells;organic small molecules;ternary blend;solution processing;power conversion efficiency