报告题目：Probing charge dynamics in organic solar cells using optical spectroscopy
报 告 人：周慈勇博士（香港科技大学研究助理教授）
报告时间：2017年4月28日（周五）上午11:00
报告地点：北区发光材料与器件国重502会议室
 
摘要：
 
The power conversion efficiency of a bulk-heterojunction organic photovoltaic blend is governed by charge separation and recombination processes at short timescales. A physical model of these processes can be developed using optical spectroscopy techniques with femtosecond resolutions, such as transient pump-probe spectroscopy. In this talk, I will review the use of optical spectroscopy for understanding charge dynamics in organic photovoltaic blends, and discuss how this technique was used to reveal the important role of spin in charge recombination1,2. This spin recombination pathway can significantly limit the solar cell efficiency, and is energetically favored for systems that are designed to have low photovoltage losses3.