新型非贵金属染料敏化剂的理论设计与筛选

In this project, novel dye sensitizers will be theoretically designed and screened for the crucial photon-to-eletron conversion materials in dye-sensitized solar cell (DSSC), based on non-noble metal (Cu and Zn) complexes and dithiafulvenyl (DTF) organic compounds: (1) we optimize the geometrical configurations of dye sensitizer to analyze their stability and electronic structure; we model the adsorption spectra to investigate the spectral response range and intensity, and analyze the photon-to-eletron conversion mechanisms according to the transfer route of excited electrons and lifetime of the excited dye sensitizers; we investigate the chain effect of functionalized ligands → geometrical configuration → electronic structure → adsoption spectral property → light-harvesting efficiency to analyze the crucial factors for improving the efficency, and summarize the function and role of the functionalized ligands in different kinds of dye sensitizers; (2) the mechanisms of electron injection are investigated by means of the adsorption sites and stability of dye sensitizers with different anchoring groups on TiO2 surface, as well as injection routes and time of electrons from the excited sensitizers into semiconductor; subsequently, we screen anchoring groups for dye sensitizers with strong bonding and electron-withdrawing capabilities, and convenient electron transport properties to facilite the electron injection, and mechanisms for effectively preventing electron recombination would be elaborated. The outcomes of this project would provide theoretical guidance for the improvment of dye sensitizers with low-cost, high efficienct, and pollution-free materials.

本研究拟通过对染料敏化太阳能电池中关键光电转换材料-染料敏化剂的理论研究，从微观层次设计与筛选一系列全新非贵金属Cu、Zn染料敏化剂及二硫富瓦烯基纯有机染料敏化剂:（1）优化染料敏化剂几何构型，分析其稳定性及电子结构特点；对稳定构型分子模拟其吸收光谱范围及吸收强度，并分析受光激发电子转移路径、激发态寿命以阐明光电转换机理；依据"配体→几何构型→电子结构→吸收光谱特性→吸光效率"连锁效应分析影响吸光效率的关键因素，总结各类配体在不同类型非贵金属染料敏化剂中的作用规律；（2）研究链接不同吸附基团染料敏化剂在TiO2表面的吸附方式及吸附稳定性、受光激发电子注入半导体方式、注入时间及转移路径以阐明从染料敏化剂至半导体的电子注入机理；遴选利于表面吸附、电子传输便利的吸附基团以增强电子注入能力，并阐述有效防止电子复合机理。本项目成果可为开发低成本、高效率、无污染的新型染料敏化剂提供直接理论指导。

能源短缺与环境污染是当今人类面临的重大难题，在保证人类赖以生存的自然资源和环境基础上实现经济与社会的可持续发展已成为人们日益关注的焦点。太阳能因其储量丰富、清洁无污染、方便开发等诸多优点而成为未来基础能源的重要组成部分之一。作为一种具有光电活性的材料，光敏化剂能有效地实现光能与电能之间的转换，展现出了响应速度快、成本低、存储密度高、结构易修饰、易于大面积制备等优势，因此在太阳能电池、光敏传感、生物医学等方面具有广阔的应用前景。. 本研究通过对染料敏化太阳能电池中关键光电转换材料—染料敏化剂的理论研究，从微观层次设计与筛选一系列全新非贵金属Cu、Zn染料敏化剂纯有机染料敏化剂:（1）优化染料敏化剂几何构型，分析其稳定性及电子结构特点；对稳定构型分子模拟其吸收光谱范围及吸收强度，并分析受光激发电子转移路径、电子转移量、转移距离、激发态寿命以阐明光电转换机理；依据“配体→几何构型→电子结构→吸收光谱特性→吸光效率”连锁效应分析影响吸光效率的关键因素，总结各类配体在不同类型非贵金属染料敏化剂中的作用规律；（2）研究链接不同吸附基团染料敏化剂在TiO2表面受光激发电子注入半导体方式、注入驱动力以阐明从染料敏化剂至半导体的电子注入机理；遴选电子传输便利的吸附基团以增强电子注入能力，并阐述有效防止电子复合机理。本项目成果可为开发低成本、高效率、无污染的新型染料敏化剂提供直接理论指导。