Chemists at FAU want to continue to increase the efficiency of organic photovoltaics

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Chemists at FAU hope to push the boundaries of organic photovoltaics. (Image: shutterstock)

New molecule design for more solar power

Chemists at FAU hope to use optimized carbon-rich molecules to push the boundaries of organic photovoltaics. In the project UP&DOWN, carbon compounds are to be designed in such a way that sunlight striking them is used significantly more effectively, thereby generating more electrical current. Spectroscopy in the femtosecond timescale should help the researchers gain a better understanding of the underlying processes and accelerate the development of the new classes of molecules.

At FAU, great efforts are being made to improve the performance of organic solar modules on the basis of carbon compounds. One promising approach involves the optimal use of singlet fission (SF) and triplet-triplet annihilation (TTA):

In the case of singlet fission, one high-energy photon produces not one but two excited states, and in the case of TTA, two low-energy photons are used to lift a molecule into a considerably higher energy level one step at a time. A fundamental understanding of these two mechanisms will facilitate the development of considerably more effective solar modules.

Researchers at the Chair of Physical Chemistry I led by Prof. Dr. Dirk Guldi and Prof. Dr. Rik R. Tykwinski from the University of Alberta, Canada, intend to develop materials that allow both processes to be combined in one photovoltaic module. The new project named “Improved generation of solar energy by optimizing up and down conversion in organic molecules (UP&DOWN)” is focusing on acenes, aromatic hydrocarbons consisting of a linear chain of benzene rings.

The researchers’ idea is to replace individual rings with other molecule groups and thereby optimize the properties of the organic material. Using cutting-edge spectroscopy, the researchers hope to observe the reactions of these new molecules in the femtosecond timescale and decode the above-mentioned reaction mechanisms.

UP&DOWN was derived from the FAU’s project “Singlet fission in novel organic materials – an approach towards highly-efficient solar cells,” which focused on singlet fission and was funded by the Emerging Fields Initiative (EFI). With the EFI, FAU supports particularly high-risk, interdisciplinary collaborations within the University.

Further information:

Prof. Dr. Dirk M. Guldi

Chair of Physical Chemistry I

Phone: +49 9131 85 27340