卟啉类给受体染料的设计、合成及在染料敏化太阳电池中的应用

Considering several key issues such as inefficient light absorption, aggregation of porphyrin dye molecules and poor device stability in porphyrin dye-sensitized solar cells (DSCs), the objective of this project is to improve cell efficiency and stability by developing novel porphyrin dyes with enhanced light-harvesting capacity in the visible and near-infrared regions, large steric hindrance and supramolecular function to tune the self-assembly of prophyrin dye molecules on titania nanocrystals and related interfacial charge transfer kinetics, with the aid of theoretical calculation. We will also screen various electron acceptors of push-pull porphyrin dyes, which can endow a stronger binding of dye molecules on titania nanocrystals and improve the stability of dye-sensitized solar cells. Furthermore, joint electrical and photophysical techniques will be deployed to scrutinize the intrinsic relationship between dye molecular structure and energy levels, dye coverage and gesture on titania nanocrystals, light absorption as well as cell efficiency, providing a basis for the R&D of high-performance porphyrin dyes for DSCs.

针对目前卟啉类染料敏化太阳电池所遇到的光吸收不够好、分子聚集、电池稳定性差等问题，本项目以提高器件效率和稳定性为目标，拟结合理论计算与模拟，设计并合成在可见光区和近红外区有较强光吸收能力的染料，开发具有较大立体位阻效应和超分子特性的染料来调控染料在二氧化钛纳晶上的自组装及界面电荷转移动力学，并筛选电子受体的连接基团，增强染料与二氧化钛纳晶之间的相互作用，提高电池稳定性。结合电学与光物理技术研究染料分子结构和能级、界面覆盖度与卟啉染料吸附姿态、光吸收与器件功率转换效率的内在联系，为进一步高性能染料开发提供基础。

针对目前卟啉类染料敏化太阳电池所遇到的光吸收不够好、分子聚集等问题，本项目结合理论计算，设计并开发出10余种新型宽光谱吸收、高摩尔吸收系数及长激子寿命卟啉类染料。通过染料敏化太阳电池界面光电功能分子层的微结构表征及电荷转移动力学测量，初步揭示了卟啉染料分子化学结构等关键元件依赖的界面复杂多通道电荷转移动力学规律及其微观起源，为进一步高性能染料敏化太阳电池的理性设计提供了重要的科学参考。基于“半导体表面纳米微孔缺陷填充”及“共染色”的概念，利用新开发的新型卟啉染料，制备出功率转换效率达14.1%的染料敏化太阳电池。