EU funding strengthens solar cell research at HZB
Ultra-high vacuum system in the Energy Materials In-Situ Lab (EMIL) that will combine industry-relevant deposition tools with a suite of complementary advanced characterization methods. © R.G. Wilks
Marcus Bär and his team are participating in two international projects being funded under the EU Horizon 2020 research programme. Both research projects are concerned with development and optimisation of high-efficiency thin-film solar cells based on chalcopyrites (“Sharc 25") and kesterites (“SWInG”). These two projects will together bring in about 900,000 EUR of additional research funding for solar cell research.
The two projects, Sharc25 and SWInG, will be funded under the EU’s Low-Carbon Energy section. “The advanced material characterisation at HZB will focus on the interface characteristics of solar cell structures. Particularly, the complementarity of the suite of instruments at the newly established EMIL lab at BESSY II will benefit this research”, explains Prof. Marcus Bär, who heads the Young Investigator Group - Interface Design at HZB.
“Sharc25" stands for “Super High-Efficiency Cu(In,Ga)Se2 Thin-Film Solar Cells Approaching 25%”. The project will focus on pushing the performance of Cu(In,Ga)Se2 (CIGSe) thin-film solar cells towards 25 % conversion efficiency, which is considerably higher than the efficiency of market-dominating polycrystalline silicon cells. Achieving this level of efficiency would provide a significant competitive advantage for the European thin film PV industry. The research project will be coordinated by the Centre for Solar Energy and Hydrogen Research Baden-Württemberg (ZSW) and involves research partners from seven European countries. The project funding is 6.15 million EUR in total, of which 450,000 EUR is allocated to HZB. “We will be systematically investigating the layer stacks, particularly focusing on understanding the properties and processes at the interfaces. Optimising the interface behaviour is a fundamental prerequisite for driving the efficiency towards its theoretical limit”, says Bär.
SWInG (Development of Thin-Film Solar Cells based on Wide Band-Gap Kesterite Absorbers) is to receive 3.8 million EUR and will be coordinated by imec (Interuniversity Micro-Electronics Centre/Belgium) and includes partners from the Netherlands, France, Germany, and Sweden. 450,000 EUR are allocated to HZB. The objective of the research is to develop inexpensive, dependable tandem solar cells that have the potential of converting more than 30% of sunlight into electricity. The wide band-gap solar cell absorbers necessary for this will be achieved by modifying the composition of the kesterite. “Kesterite absorber layers are desirable, because they consist of Earth-abundant elements. In addition, the band gap can be adjusted by varying the composition of the material, matching it to the requirements of the tandem solar cell”, explains Bär.
- Key technology for a future without fossil fuelsIn June and July 2025, catalyst researcher Nico Fischer spent some time at HZB. It was his sabbatical, he was relieved of his duties as Director of the Catalysis Institute in Cape Town for several months and was able to focus on research only. His institute is collaborating with HZB on two projects that aim to develop environmentally friendly alternatives using innovative catalyst technologies. The questions were asked by Antonia Rötger, HZB.
- 5000th patient treated with protons for eye tumoursFor more than 20 years, Charité – Universitätsmedizin Berlin and the Helmholtz-Zentrum Berlin (HZB) have been jointly offering proton radiation therapy for eye tumours. The HZB operates a proton accelerator in Berlin-Wannsee for this purpose, while Charité provides medical care for the patients. The 5000th patient was treated at the beginning of August.
- Iridium-free catalysts for acid water electrolysis investigatedHydrogen will play an important role, both as a fuel and as a raw material for industry. However, in order to produce relevant quantities of hydrogen, water electrolysis must become feasible on a multi-gigawatt scale. One bottleneck is the catalysts required, with iridium in particular being an extremely rare element. An international collaboration has therefore investigated iridium-free catalysts for acidic water electrolysis based on the element cobalt. Through investigations with various methods, among them experiments at the LiXEdrom at the BESSY II X-ray source in Berlin, they were able to elucidate processes that take place during water electrolysis in a cobalt-iron-lead oxide material as the anode. The study is published in Nature Energy.