Light Weight and Stable Organic Solar Cells for Outer Space Applications

The i-MEET institute of FAU, the Solar Factory of the Future (SFF), and the Russian Academy of Sciences (RAS) will join capacities to build organic photovoltaic devices that combine high performance with strongly reduced weight and increased radiation hardness, making them apt for deployment in communication satellites. The project is jointly funded by DFG and RAS for a duration of 3 years.

Communication technologies in space is a strongly expanding market promising ubiquitous high-speed data transfer. However, the silicon based solar panels, currently used to power the satellites, are heavy during spacecraft uplift, and their operational lifetime in space is limited. This is because silicon, a crystalline inorganic semiconductor, is highly sensitive to defects which are introduced by hard gamma rays in outer space.

Organic solar cells can in principle solve both problems. They are lightweight and flexible, which is optimal for space transport. Moreover, organic materials contain only few heavy atoms so that they interact very little with gamma rays. However, only few of the modern high performance photovoltaic materials have so far been investigated for their “radiation hardness”. In this project, we will apply a high throughput approach to investigate the radiation hardness of a large library of organic electron donor and acceptor materials with systematically varied chemical structure. Dr. Larry Lüer of the team at i-MEET will apply state of the art machine learning techniques to identify structural motifs that are stable against photodegradation or even able to revert it (so-called “self healing”), while not compromising high performance in solar power generation. 

To build complete solar devices, not only the active materials but also the other components must be optimized for low weight and radiation hardness, namely electrode coatings, charge-transport layers, adhesives and encapsulation. Therefore, the project consortium excels along the full value added chain of photovoltaics. Prof. Pavel Troshin (RAS) is renowned in advanced organic synthesis and radiation hardness characterization; Prof. Christoph Brabec (FAU, director of i-MEET) is among the leaders in high throughput device formulation and characterization in photovoltaics; the SFF, led by Dr. PD Hans-Joachim Egelhaaf, currently holds the world record for efficiency in modules of organic photovoltaics.