High Entropy Acceptor Mixtures for Stable Organic Solar Cells

Research Project, 2023 – 2026

Organic solar cells receive considerable attention as an alternative photovoltaic technology with a low carbon footprint. Remaining challenges are the realization of sustainable production processes that avoid harmful solvents and a high degree of thermal stability leading to devices with a long lifetime. The use of binary and even ternary acceptor mixtures is gaining attention as a tool to tackle these challenges. Own results indicate that mixtures of as much as eight different organic semiconductors can display an unprecedented ability to form a molecular glass. Motivated by these results, the goal of this project is to investigate how the gain in entropy upon mixing of a large number of acceptors can improve the processability and thermal stability of photovoltaic blends. Four central research questions will be addressed:- How does mixing of acceptor molecules influence the solubility?- How does mixing of acceptor molecules influence the solid-state phase behavior?- What is the optimal number of components of an acceptor mixture?- Can multicomponent acceptor mixtures improve the thermal stability of organic solar cells?The project will run as a PhD student project over four years and combine thermal and structural analysis with stability testing of devices. The knowledge gained will provide a complete picture of the potential benefit of multicomponent acceptor mixtures, advancing the field of organic photovoltaics as well as organic electronics in general.