I am a member of the Max Planck Research Group for Organic Optoelectronics located at the Max Planck Institute for Polymer Research in Mainz. I am interested in using spectroscopy to probe the processes within organic solar cells, in particular to understand charge and energy transfer mechanisms in polymer:fullerene blends.
Many high-performance organic photovoltaic systems have been developed in recent years, and the question I would like to answer is: what are the factors determining whether a polymer:fullerene blend will produce a high photovoltaic efficiency? Approaching this question from the other side, we can also ask: what are the mechanisms which reduce solar cell efficiency, and how are these minimised in efficient photovoltaic devices?
Spectroscopy, particularly fast, time-resolved spectroscopy, is a powerful tool to monitor the evolution of excited states in polymer:fullerene blends, and to uncover the details of the charge generation and loss mechanisms. By understanding these mechanisms, and relating them to the chemical structure and packing characteristics of the constituent materials, we hope to guide the synthesis of the next generation of organic photovoltaic materials.