Perovskite based solar cells have in the last years become a dynamic research field which promises to change the way we will produce electricity in the future. In our research group we work on perovskite based solar cells especially tandem solar cells. We are a team of 15 group members who come from a variety of countries, scientific disciplines ad career stages. For 2027 we are looking for students who are interested to join us for their master thesis research project. We work experimentally and it can take a while to learn the needed techniques, so we typically aim to have students in our group for at least 9 months. Depending on the requirements of your course this may be best done by combining HiWi time with the master thesis. Our group is based at the Fraunhofer Institute for Solar Energy Systems (Fraunhofer ISE) and the INATECH Institute of the Technical Faculty of University of Freiburg. We welcome Freiburg master students from a variety of courses including physics, sustainable systems engineering, chemistry, and other related subjects.
Below is a brief description of some of the projects we are currently offering. If you are interested in doing your thesis with us please contact Dr. Juliane Borchert (juliane.borchert@ise.fraunhofer.de) with a CV, transcript of grades, and some information about the course you are taking.
Topic A) Improving the Stability of Perovskite Materials
Wide-bandgap metal-halide perovskites are promising materials for optoelectronic applications, particularly for high-efficiency tandem solar cells and potentially low-cost photovoltaic devices. Despite substantial progress in compositional and interfacial engineering, simultaneously achieving high efficiency and long-term operational stability remains a major challenge.
The aim of this master’s thesis is to optimize the composition of multi-cation, mixed-halide perovskite absorbers, FAyCs₁₋yPb(IₓBr₁₋ₓ)₃, to mitigate phase segregation and ion migration under photothermal stress. The project will investigate replacing mixed-halide systems with single-halide, iodide-only perovskite compositions. The cesium (Cs) content will be systematically tuned to maintain the desired bandgap range and improve the operational stability of perovskite solar cells.
Your tasks
- Deposit perovskite absorber thin films in an inert atmosphere (glovebox)
- Characterize the structural, optical, and electrical properties of the layers (e.g., XRD and J–V measurements)
- Perform photothermal degradation tests to evaluate device stability
Your qualifications
- Knowledge of or experience in chemistry, semiconductor materials, material characterization, and the safe handling of hazardous chemicals
- Enrolment in a science or engineering degree program; chemistry, materials science, or physics is preferred
