半导体纳米材料的多激子产生研究

项目名称： 半导体纳米材料的多激子产生研究

项目编号： No.11274161

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 王晓勇

作者单位： 南京大学

项目金额： 90万元

中文摘要： 发展基于太阳能全光谱利用的低成本太阳能电池，探索大幅度提高其光电转换效率的新结构、新材料、新方法，已经成为当前最为前沿的基础和应用研究领域之一。半导体纳米材料体系中的多激子产生过程能够充分利用太阳光光谱中的紫外波段，解除一个吸收的单光子最多只能产生一个电子-空穴对的限制，从而革命性地提高太阳能电池的光电转换效率，对于解决能源危机和减少环境污染具有战略性的意义。本项目计划结合单分子光谱和超快光谱技术，通过泵浦-探测、受激拉曼、共振能量转移和稳态光谱测量等方法系统地研究各种半导体纳米材料体系中的多激子产生过程和物理机制。项目的主要研究目标包括：探索半导体纳米材料多激子产生测量的新方法，澄清胶体量子点体系中多激子产生效率的争议，展现自组装量子点和碳纳米结构等新体系中的多激子产生过程，并提出利用多激子产生效应优化光伏器件的应用方案。

中文关键词： 多激子产生；载流子倍增；能量转移；单粒子光谱；半导体纳米晶

英文摘要： The development of new structures, materials and methods to increase the photon-to-electron conversion efficiency of low-cost solar cells has become one of the most active areas in both fundamental research and device applications. The multiple exciton generation (MEG) process of semiconductor nano-materials can make full use of the ultraviolet radiation in the solar spectrum by creating multiple electron-hole pairs upon absorption of a single photon. Thus, the researh of MEG effect has the potential to greatly increase the photon-to-electron conversion efficiency in solar cell devices and will play important roles in solving the current energy crisis and decreasing the environmental pollution. In this project, we plan to use single molecule spectroscopy and ultrafast optical techniques, including pump-probe, stimulated Raman, resonant energy transfer and integrated spectrum measurments, to systematically study the MEG process and its underlying physical mechanisms in various semiconductor nano-materals. The main research directions of this poject include: (1)Investigating novel optical techniques for the measurement of MEG effect in semiconductor nano-materials; (2)Elucidating the current controversy on MEG effect in colloidal quantum dots; (3) Demonstrating MEG effect in new material systems such as self-assem

英文关键词： multiple exciton generation；carrier multiplication；energy transfer；single-particle spectroscopy；semiconductor nanocrystal