Abstract: Understanding Dye-Sensitized Solar Cells

My name is Simran Rohatgi and I am a senior in Dr. Kristin Wustholz’s Physical Chemistry lab. My project deals with understanding how dye-sensitized solar cells (DSSCs) work on the molecular level to harness solar energy and convert it to electricity. Relative to traditional silicon-based solar cells, DSSCs inexpensive and versatile, but they are not as efficient as silicon-based cells and therefore are not widely used. A molecular-level understanding of the electron transfer (ET) processes that take place inside the DSSC may help us understand why they are not as efficient as expected. Once we gain this understanding, scientists may be able to improve the efficiency of DSSCs so that they can begin to play a role in solving the energy crisis facing our planet. This summer, I hope to study DSSC systems using a combination of single molecule (SM) and fluorescence lifetime spectroscopies. SM studies allow us to observe ET processes of individual dye molecules, instead of obtaining averaged data, which would be less valuable due to the heterogeneous nature of the environment inside DSSCs. Additionally, fluorescence lifetime measurements will allow the observation of ET processes down to the picosecond timescale. The molecular-level understanding provided by these combined techniques may help us to explain the plateau in dye-sensitized solar cell (DSSC) efficiency that has been observed in the past decade.