Jena research team presents novel approach to the storage of solar energy
Using the energy from the sun as efficiently as nature does and converting it into chemical energy could drastically reduce global CO2 emissions. A research team from the Leibniz Institute of Photonic Technology (Leibniz IPHT) and the Friedrich Schiller University Jena has now come one step closer to this vision. The researchers have developed a chemical system that collects light energy and stores it on a molecule for at least 14 hours. Based on a copper complex, their system thus decouples photochemical processes from the day-night cycle — thus overcoming a barrier that previously made solar-powered photochemistry unsuitable for continuous industrial production processes. The researchers published the results in the renowned „Journal of the American Chemical Society“ in August 2020.
Nature has already solved the problem: In photosynthesis, plants use sunlight to convert carbon dioxide into chemical compounds — in such a way that the solar energy stored in chemical bonds is also available when it is dark. Researchers are attempting to imitate this process using nature as a model; however, solar-driven photochemistry has so far only worked in bright light due to a lack of suitable storage facilities.
Molecular approach enables light-driven photochemistry in the dark for the first time
The research team from Leibniz IPHT and the University of Jena is now presenting a molecular approach to the storage of solar energy, which for the first time makes it possible to decouple photochemical reactions from the day-night cycle and allow them to take place independently of daylight. In contrast to previous approaches, which are based on solid state materials, the researchers generate reactive photoredox equivalents on a small molecule. This enables them not only to store the light energy for a previously unattained duration of at least 14 hours, but also to regenerate it when needed.
„The dependence on brightness and darkness has so far been a major hurdle when it comes to using solar-powered photochemistry for continuous industrial production processes,“ explains main author Dr. Martin Schulz, who conducts research at the University of Jena and Leibniz IPHT. „We assume that our results will open up new possibilities to research systems for the conversion and storage of solar energy as well as for photo(redox)catalysis“.
High charging capacity even after several cycles
In the chemical system developed by the Jena researchers within the Collaborative Research Center „CataLight“, the photosensitizer and the charge storage unit are located on the same small molecule. This eliminates the need for intermolecular charge transfer between a separate sensitizer and a charge storage unit. The system retains three quarters of its charge capacity even after four cycles.
The researchers use a copper complex and thus a molecule based on a readily available metal, whereas previous approaches used rare and expensive precious metals such as ruthenium. The doubly reduced copper complex can be stored after photochemical charging and used as a reagent in dark reactions such as the reduction of oxygen.
The Jena researchers developed the approach together with partners from the University of Ulm, the Leibniz Institute for Solid State and Materials Research Dresden and Dublin City University. In the Collaborative Research Center „CataLight“ („Light-driven Molecular Catalysts in Hierarchically Structured Materials — Synthesis and Mechanistic Studies“) teams of scientists from the Universities of Jena and Ulm are researching sustainable energy converters modeled on nature.
Martin Schulz, Nina Hagmeyer, Frerk Wehmeyer, et al. (2020), Photoinduced Charge Accumulation and Prolonged Multielectron Storage for the Separation of Light and Dark Reaction. J. Am. Chem. Soc. 2020, August 22, 2020. https://doi.org/10.1021/jacs.0c03779
Leibniz IPHT works on the first German quantum computer as part of the collaborative project QSolid
Building a complete quantum computer is the goal of the five-year QSolid collaborative project, 89.8 % of which are funded by the German Federal Ministry of Education and Research. The quantum computer to be developed will contain several next-generation superconducting quantum processors and will significantly exceed the computing power of today’s supercomputers for specific tasks. Core expertise and initial circuits also come from Thuringia: Leibniz IPHT is contributing its experience in the production and characterization of superconducting circuits to the project and will help to advance the realization of significantly more powerful quantum computers by developing new fabrication processes.
Published now: Annual Report 2021 provides insights into the research of Leibniz IPHT
The new annual report of Leibniz IPHT guides you visually impressive and entertaining through an eventful and successful year 2021. Exciting projects, fascinating research topics as well as current facts and figures from the reporting period take interested readers on a scientific journey of discovery.