Energy transfer and charge separation in Organic Photovoltaic materials
Title: Energy transfer and charge separation in Organic Photovoltaic materials
SNIC Project: SNIC 2021/22-353
Project Type: SNIC Small Compute
Principal Investigator: Shan Anjum <shan.anjum@liu.se>
Affiliation: Linköpings universitet
Duration: 2021-05-03 – 2022-06-01
Classification: 10304
Keywords:

Abstract

The advent of non fullerene acceptors have boosted the performance of organic photovolatic devices to 18%. The introduction of these new materials have brought up questions regarding the physics of the solar cells and there are many questions left to address. Compared to their inorganic counterparts the energy losses are still quite huge, specially in regards to the non-radiative decay. The charge separation is also a process worth investigating, the spontaneous splitting of an exciton would require about 0.5 eV, but the magnitude of the thermal fluctuations KbT is only 0.025 meV, this also posses the question about how these charges might get split and how it correaltes to the voltage losses in the devices. Experimental findings show that many non-fullerene acceptors show different absorption and emission spectra in solution compared to film. We wish to investigate why this occurs and what morphological properties might be at play that might affect this. Furthermore it is also interesting to relate these morphological features to the properties of energy loss and charge separation. Through our calculations, we wish to understand the electron-vibration coupling and see how it affects the non-radiatve losses in our solar cells.