The transition to renewable energy could be made easier by organic solar cells. This transition is possible thanks to a low-cost synthetic route and high cell efficiency. A new material class known as “nonfullerene absorbors” has been discovered. It is a cheaper synthetic route than traditional silicon solar cells and offers a higher efficiency level than first organic solar cells.
Designing materials that are non-fullerene accepting and have properties suitable for solar cells remains challenging. This new design method was developed by Denis Andrienko (department of Kurt Kremer, Max Planck Institute for Polymer Research) and his colleagues. This design method uses organic solar cells that have high efficiency and is divided into multiple building blocks. These fragments can either be electron-donating or electron-accepting molecular components, also known as “donors” and “donors”. Donor and acceptor blocks from different solar cells can be combined to create new “nonfullerene-acceptor” molecules that can be used in solar cells.
Kun-Han Lin, the co-author of this study, said it is difficult to choose the right molecular compound from the many available.
Design algorithms include constraints that limit the number of non-fullerene accepting molecules. These include molecular symmetry and quadrupole moment. For example, in cases where an acceptor-donor-acceptor combination is used, the two acceptor building blocks are always of the same type.