Research

Solar energy conversion (SEC) transforms radiant energy from the sun into usable forms of energy such as electricity, thermal heat, and chemical fuels.  SEC involves distinct fundamental processes depending on whether sunlight is harvested to generate electricity through photovoltaics or to produce chemical energy through photochemical reactions, such as photocatalysis. Both approaches rely on a sequence of interconnected physical processes that integrate photon management with charge management and, ultimately, charge storage in molecular and particulate materials.

Photon management aims to optimize the use of the solar spectrum for photovoltaics, photocatalysis, and related applications.  Key approaches include linear, resonant processes such as photon down- and up-conversion, as well as down- and up-shifting. This concept can be further extended to nonlinear, non-resonant processes, including two-photon absorption. The ultimate goal is to match the energy of absorbed photons to the requirements of charge management, thereby maximizing photon utilization, minimizing energy losses, and pushing solar energy conversion efficiencies beyond current limitations.

Charge management complements photon management by encompassing the fundamental processes governing the generation, separation, shift, and collection of photogenerated charge carriers, namely electrons and holes. Advances in the field transcend the management of a single set of charge carriers to multiple charge-carrier populations.  Ultimately, the emphasis is on enabling efficient charge storage within functional devices and catalytic systems.

The performance, cost and scalability of any solar technology are ultimately limited by the materials at hand. FAU Solar initiates and drives research to discover and develop molecular, hybrid and inorganic semiconductors and functional materials tailored to solar energy conversion. Its scope goes well beyond photovoltaics. Purpose-designed materials are equally needed for photo- and electrocatalysis, light conversion and spectral shifting, photon storage, and broadband harvesting of electromagnetic radiation and other forms of ambient energy.

The central approach is an integrated discovery workflow that closes the loop between theory, synthesis and characterization. Theoretical modelling and computational screening define promising regions of chemical and structural space. Ultrafast synthesis and characterization cycles then realize and evaluate candidate materials. Machine learning routines connect these steps, learning from every experiment to propose the next one. All of this will run on high-throughput robotic platforms, so that iterative cycles of design, fabrication, testing and analysis can be carried out with minimal human intervention. The result is a move from serendipitous, sequential materials research toward truly autonomous discovery and optimization, in which materials properties, processing conditions and device performance are improved together.

By bundling expertise in chemistry, physics, materials science, engineering and data science across FAU, the section aims to shorten development times for new functional materials from years to months. It also seeks to generate structured, reusable datasets for the wider community, and to provide the materials foundation for the next generation of solar energy technologies.

At FAU Solar we investigate solution processed photovoltaics, covering the full value-added chain from material synthesis and device formulation up to device integration and upscaling towards industrial production. Device performance and operational lifetimes are equally important for us. This quest not only calls for novel materials but also for advanced device architectures and smart system integration, being focus areas of FAU Solar.

We use tandem architectures to overcome the single junction efficiency limit. Combining two prominent PV technologies in the same device (perovskites and organic photovoltaics), we manage to increase performance and at the same time boost operational lifetimes. Using smart system integration, we aim to push spectral sharing concepts for sunlight in densely populated areas towards a true win-win for all stakeholders. Examples include: Agrivoltaics (additional PV electricity without reduced plant growth) and window integration (additional PV electricity without shading and without airconditioning). We also perform research on novel systems for photoelectrocatalysis to convert sunlight into chemical energy.

Energy conversion relies on the exchange of electrons across semiconductor interfaces. In fact, energy conversion occurs as electrons are exchanged across the interface. This exchange is crucially affected by the atomic-scale structure of the interface and can become enabled or blocked by the most minute changes.

Therefore, FAU Solar scientists invent methods for placing layers and patterns of solids onto the surface of other solids with the ultimate level of control, that is, with atomic accuracy. To achieve this, we combine fundamental science ingenuity with engineering prowess. The natural science facet consists in the chemical design of molecular reagents which encode in their chemical structure the information as to the placement of individual atoms to specific positions of the surface. The engineering counterpart scales individual local events up to highly reproducible processes, repeated accretion steps result in the additive generation of semiconductors and further functional materials.

By combining expertise from chemistry, chemical engineering, materials science and solid-state physics, FAU Solar provides the physical counterpart to the advanced data processing ability enabled in data science for the accelerated design and testing of advanced materials and functional structures.

The economic and societal impact of solar energy depends not only on technological performance, but also on market conditions, regulatory frameworks, and the decisions of individuals, firms, and policymakers. Understanding these factors is essential for assessing the potential of emerging technologies and identifying the conditions under which they can be successfully adopted and deployed.

FAU Solar brings together perspectives from economics, business research, psychology, and related social sciences. Research topics include the economic assessment of solar energy technologies, electricity market design and regulation, business models and investment decisions, as well as the behavioral and organizational factors influencing technology adoption. Further questions concern the distribution of costs and benefits, public acceptance, and the broader societal implications of the transition toward solar-based energy systems.

By complementing technological research with economic and social science perspectives, the section aims to contribute to a more comprehensive understanding of the opportunities and challenges associated with solar energy conversion and to inform decisions by policymakers, businesses, and other stakeholders.

Solar energy conversion involves processes on many scales, from charge generation and transport in a material to devices, modules and complete energy systems. FAU Solar describes the corresponding processes across scales and keeps them aligned with experimental and operational data. The developed digital twins make it possible to understand, predict and optimize the behaviour of materials, devices and systems before they are fabricated or deployed, and to monitor and control them during operation.

The digital twins are built from the fundamentals. Physical and chemical models of the underlying conversion processes form their core and are combined with data-driven components wherever first-principles descriptions are incomplete or too costly to evaluate. Equally central is the development of new mathematical and computational methods. These include Bayesian optimization and optimal experimental design to decide which experiment or simulation is most informative next, surrogate and reduced-order models for fast evaluation, uncertainty quantification, and optimization to determine designs and operating strategies that remain reliable under uncertain conditions. In this way, the digital twins provide the decision layer for the autonomous discovery and optimization workflows pursued within FAU Solar, and they link findings on fundamental processes, materials, processing and device architectures to questions of system integration and economic assessment.

By bundling expertise in mathematics, physics, chemistry, materials science and engineering across FAU, the section aims to reduce the number of costly experiments needed to reach a target, to make design decisions transparent and quantifiable, and to transfer methods developed for solar energy conversion to related fields.

Founded in 2007, ICMM promotes interdisciplinary research at the intersection of chemistry, physics, and material science. It focuses on the development of materials based on molecular building blocks, with applications in nanoelectronics, medicine, and energy conversion technology. ICMM collaborates with industrial laboratories to explore new applications for molecular materials.

Established in 2008, ECRC brings together scientists from chemical engineering, synthetic organic and inorganic chemistry, as well as experts in physical and theoretical chemistry. The center specializes in investigating molecular interfaces, interface formation, and structure-property relationships. It plays a vital role in emerging material concepts and photon-time management.

The IZNF research building, inaugurated in 2019, provides a platform for interdisciplinary research on nanostructured thin films. Scientists from various disciplines collaborate to develop a unified methodology for different application areas such as photonics, optoelectronics, catalysis, and energy technology.

Established in 2010, CENEM offers cutting-edge instrumentation and expertise for the microscopic and analytical characterization of materials and devices at the atomic scale. The center focuses on electron microscopy, X-ray microscopy, cryo-TEM, scattering methods, scanning probes, and atom probe microscopy. It contributes to the development of materials and devices for photovoltaic applications.

Established in 2005, ZMP conducts interdisciplinary research at the interface of materials science, mechanical engineering, chemistry, and physics. The institute develops new material concepts and corresponding production techniques, with a particular focus on lightweight functional components and 3D printing technologies. ZMP’s research is relevant to solar module processing and improves the efficiency of PV systems.

NHR integrates systematic and model-guided performance engineering into computing-related research. The center develops analytic performance models, tools, and libraries, providing insights into performance issues and optimizing performance. NHR also develops teaching material and courses that promote performance-aware programming.