Solar cells have played a crucial role in renewable energy efforts and the Green Deal in recent years, helping to drive the green energy transition and enabling smaller actors and citizens to adopt green energy or achieve carbon neutrality. Metal halide perovskites (MHPs) show great promise for solar cells due to their high efficiency and performance. However, without a deeper understanding of MHP properties, this technology cannot reach its full potential. The ERC-funded PEROVAP project will explore vapour deposition as a production method to better control and engineer MHP structures and properties. Additionally, the project will develop innovative engineering methodologies to create new material structures and further advance this promising technology.
This project has received funding from the Horizon Europe Framework Programme, Grant agreement ID: 101087679
The advent of hybrid perovskite solar cells has given rise to extraordinary photovoltaic performance. However, the new physical characteristics of these materials are not yet completely understood, including the role of ionic and electronic defects on the solar cell performance, hysteresis and stability. In this proposal we will explore and characterize the nature of defects in lead halide perovskite thin films and photovoltaic devices, investigate how they influence the long-term stability and explore mitigation strategies for their passivation. We will fabricate both vertical photovoltaic devices and lateral devices from methylammonium lead triiodide and triple cation based perovskites, and tune the defect density in the perovskite active layer by varying the stoichiometry of the precursor solution with high precision in a systematic fashion. The relation of defect states and their properties — type, activation energy, concentration, distribution, surface or bulk, etc. — to the solar cell parameters and degradation will be investigated in view of the fractional changes in stoichiometry. We will apply a complementary combination of experiments, including time-resolved, spatially-resolved and temperature dependent electronic and optical methods to obtain a clear physical picture of the role of defects in perovskite materials. Beyond this fundamental understanding of defect physics, it is our goal to identify the nature of the most prominent defect states in lead halide perovskite solar cells and to pursue strategies for their passivation in order to improve both the performance and the long-term stability of perovskite photovoltaic devices.
EIFFEL’s (EffIcient Fullerene-Free organic solar cELIs) aim is to recruit and train 10 young and talented Doctoral Candidates (DCs) who, in the framework of their doctoral training programmers, will address these two challenges by developing efficient NFAs, revealing the mechanisms of degradation in NFA-based OSCs, and establishing synthetic strategies for their mitigation to form the basis for a new generation of OSCs - compatible with mass production - for successful commercialization.
The training program of EIFFEL will have two main positive effects: raising new academic experts for a career in academic sector, and meeting the growing demand of trained professionals in the energy industrial sector including SMEs. Both effects can be reached on the short-term, i.e. directly after the end of the project.
To learn more about the project, please check the website: EIFFEL doctoral network
This project has received funding from the Horizon Europe Framework Programme under the Marie Skłodowska-Curie Doctoral Networks Grant Agreement - GA-101119780
The emerging Internet of Things (IoT) promises to enhance the quality of our lives by fundamentally changing the way we interact with electronics. For such a sweeping change to occur, semiconductor manufacturing needs to transition to techniques that circumvent the technological and economical constraints imposed by traditional vacuum deposition. Solution-processability brings a key advantage, allowing fabrication under ambient conditions, but the toxicity of the solvents represents a barrier to the industrialization. Hence, exploration of alternative methods that offer the same cost efficiency and scalability, but avoid the pitfalls of solution coating, is urgently needed. We have assembled a team with complementary expertise in the areas of materials processing, spectroscopy, and device physics, to address this challenge. Our vision is to fundamentally change the way in which optoelectronic devices are manufactured, by shifting the focus from solution and/or vacuum processing to laser printing, a solvent-free, environmental-friendly technique that is scalable to large-area electronics. The goal of this project is to develop the fundamental understanding of film formation processes during laser printing and to apply it towards the development of manufacturing protocols for various optoelectronic devices.
The TANGO project represents a significant leap in the realm of perovskite solar cell (PSC) fabrication, introducing a predictive model that integrates Hansen Solubility Parameters (HSPs) with Density Functional Theory (DFT). This innovative approach aims to revolutionize solvent-antisolvent selection, a critical aspect influencing PSC performance, stability, and environmental impact. Departing from the unpredictable one-step method, TANGO advocates for solvent-engineering, enhancing film quality, morphology, and overall device stability by strategically introducing antisolvents during the spinning process. Traditional solvent selection methods, marked by limitations and a lack of standardization, prompted TANGO to propose a novel, theoretical model. This predictive model seeks to systematically identify solvent-antisolvent combinations conducive to both high PSC performance and minimal environmental impact. The pressing environmental concerns associated with solvent usage in perovskite solar cell fabrication highlight the need for a more sustainable approach, aligning efficiency with environmental responsibility. The collaborative efforts of IFW and UNS-CONICET, combining Prof. Dr. Yana Vaynzof's solar cell manufacturing expertise and Prof. Dr. Ignacio López-Corral's proficiency in computational chemistry, underscore the ambitious goals of TANGO. The successful validation of the predictive model holds the promise of assisting in a new era of highly efficient and environmentally friendly PSCs, contributing significantly to the global transition towards sustainable energy solutions.
“Responsible Electronics in the Climate Change Era” (REC²) will create disruptive paradigm shifts in the conceptualisation, design, realisation, usage and end-of-life treatment of electronic devices. Our society is dependent on electronics, which are increasingly integrated into every aspect of our lives. Electronics are essential for our continued progress, providing solutions to global challenges like climate change. At the same time, electronics are also part of the problem: Their already vast energy needs continue to grow, and their ever-shorter replacement cycles drive enormous consumption.
The resulting depletion of critical natural resources is further exacerbated by difficulties with recycling: e-waste contains numerous densely packed chemical compounds that are not only challenging to separate but are also often hazardous. These multi-faceted challenges are increasingly recognised in society – including within the electronics industry and research community – and urgently demand a fundamental change in our approach to electronics. REC² will provide the science essential for the realisation of responsible electronics that integrate environmental and social sustainability criteria across all technology levels. By creating a novel library of materials that can be disassembled on demand, REC² will enable the reuse of electronic components.
Moreover, controllably biodegradable materials and devices for short-lived electronics, such as smart labels, will rot at their end-of-life and prevent e-waste entirely. REC² will address the growing demand for ubiquitous sensing and communication by demonstrating innovative, self-sufficient systems. These should ultimately replace current design and manufacturing approaches in favour of resource-saving, energy-efficient concepts to reduce environmental impact. REC² will finally identify device designs that would enable to recycle electronic components in an ecologically and economically sensible manner. To realise this highly ambitious vision, we will bring together an interdisciplinary team of natural scientists, engineers, social and environmental scientists, economists, as well as resource management and recycling experts. Our unique approach to technological innovation will respect the importance of sustainability, resource and energy management in a circular economy, laying the foundation for responsible electronics.
Together with its partners, TUD Dresden University of Technology offers a perfect match of expertise – as exemplified by an outstanding list of principal investigators – and an ideal environment for the success of the innovative and ambitious REC² approach. REC² will place the TUD at the forefront of sustainable electronics at a decisive time in the climate change era and significantly strengthen the growing microelectronics research and technology hub in Saxony.
The goal of the Research Unit POPULAR is to investigate the printing of efficient organic solar cells based on non-fullerene acceptors (NFAs). While printing of photovoltaic devices is usually done by industrially focused development with a view to commercialisation, we are convinced that the impact of printing on film formation and specific microstructure of organic solar cells deserves a detailed fundamental investigation: Our joint theoretical and experimental approach is designed to develop a deep understanding of the function–property relationships. We will apply gravure printing to first print the photoactive layer of the solar cells from different donor–acceptor combinations under systematically varied processing conditions. First, we will only print the active layer, and deposit the other layers by spin-coating and thermal evaporation. Thereafter, we will process fully-printed devices. Lab-scale spin-coated devices with the same solar cell stack will serve as reference. We will focus our study particularly on the photophysics, optical properties, energetics in dependence on the nanomorphology. This information will be combined with the photogeneration and recombination processes measured under working conditions, and modelled using multi-experiment fitting by numerical device simulations. We will use promising, commercially available NFAs to establish the printing processes, select the device architecture. Later on, novel donor NFA multiblock co-oligomers with monodisperse segments of predefined length – which will be synthesised in this Research Unit – to yield a thermodynamically stable lamellar morphology, will be integrated into printed single-component solar cells. An important aspect of this proposal will be on understanding intrinsic stability, limiting the device performance over time, and minimising degradation. With our combined, complementary approach, we will gain deep insight into the function–property relation of novel, printed fullerene-free organic solar cells, while developing the printing process tailored to the best photovoltaic performance.
The SUPERSOL project aims to strategically strengthen the establishment of a new research direction, focusing on the development of sustainable technologies, through the recruitment of Prof. Yana Vaynzof as the new director at IFW Dresden. Specifically, the project helps to establish strategies for the nanoengineering of sustainable perovskite materials by thermal evaporation - a highly scalable deposition method of great industrial relevance. The first key goal of the project is to develop additive engineering processes that enable control over the properties of the perovskite layers. The second goal is to integrate the engineered layers into functional optoelectronic devices and investigate their performance and stability.
The current level of energy consumption caused by the IT industry has reached a remarkable level of ten percent of the global energy consumption. To contribute to resolving this issue, the Leibniz Junior Research Group led by Dr. Stanislav Bodnar will establish a new energy-efficient data storage concept based on novel altermagnets, which combine antiferromagnetic spin arrangement with ferromagnetic band structure. In the project, altermagnets will be combined in heterostructures with highly efficient novel semiconductors. Such devices will be operated by ultrashort laser pulses, and information encoded in such devices will be accessed by optical and electrical transport means.
Project leader: Dr. Stanislav Bodnar
Solar cells allow the generation of sustainable electricity and are a promising option for carbon neutral energy production. Semitransparent solar cells are of particular interest for building-integrated photovoltaics. Perovskite solar cells offer many advantages over the broadly used silicon solar cells, however more research is required to develop efficient and stable semitransparent devices. By joining the expertise of two Leibniz Institutes (IFW and IPF), the collaborative project aims to address this gap. By integrating plasmonic nanoparticles into semitransparent perovskite solar cells, the project will not only explore their efficacy in increasing device performance, but also use the nanoparticles as a diagnostic tool to monitor the degradation processes that occur within the cells. The project will therefore result in a new generation of semitransparent solar cells and take an important step towards their application in building-integrated photovoltaics.
Two-dimensional perovskites (2DPs) are fabricated from bulky ammonium-based organic molecules that interact with an inorganic metal–halide framework through hydrogen bonding. Recently, it has been shown that incorporating chiral molecules into 2DPs can induce chirality-dependent properties, including the selective absorption of right- or left-handed circularly polarized light (CPL) and spin filtering of charge carriers, all without the need for an external magnetic field. This behavior is attributed to asymmetric hydrogen bonding between the chiral molecules and the inorganic network, which leads to octahedral distortions and consequently to the crystallization of 2DPs in a chiral space group. To date, chiral 2DPs have been exclusively prepared using chiral monoammonium organic cations. In this project, we propose the use of chiral bisammonium molecules, in which both ammonium groups are bound to chiral carbon atoms, leading to a 2DP phase known as the Dion–Jacobson phase. This strategy may enhance the chiroptical response of the system by inducing stronger octahedral distortions. To achieve our objectives, we must overcome the challenge of the high formation energy of this type of 2DP and its tendency to form impurity phases. This will be addressed through careful control of the thin-film deposition process of 2DPs, including the development of solvents and additives to promote the formation of high-quality films. The results of this project could lead to a new class of chiral perovskites that has not yet been described. Such materials could enhance the efficiency of chiroptical and spintronic devices and represent promising candidates for applications in surveillance systems and quantum computing.
Project leader: Dr. Lucas Scalon
Metal halide perovskites (MHP) have attracted considerable interest for a wide range of applications such as photovoltaics, light-emitting and laser diodes, and X-ray detectors due to their high absorption coefficient. They have high optical constants, high carrier mobility, long carrier diffusion range, and the unique ability to dynamically adjust the band gap, which is critical for semiconductor applications. The excellent optoelectronic properties of MHP are comparable to those of traditional inorganic semiconductors such as GaAs, but they are relatively easy and much cheaper to synthesize, making them attractive for mass production.
Technical improvements in perovskite formulations and fabrication processes have led to significant improvements in energy conversion efficiency, but since perovskite operation is still relatively new, there is great opportunity for further research into the fundamental physics and chemistry surrounding perovskites. In addition, MHP currently face some challenges and limitations, such as low stability. All of this requires additional research and development to make perovskites viable for large-scale industrial use.
The STELLAR project combines the technology-oriented research related to solution-free mechanosynthesis of powders with magnetron sputtered film deposition to produce stable hybrid organic-inorganic MHP, and the research on physical mechanisms underlining the exceptional properties of the investigated systems and the possibility of tuning them.
Determining the role of precursor stoichiometry during mechanosynthesis, the influence of target preparation parameters and sputtering details on the properties of deposited films, studying their structure and spectroscopic properties will provide new information on the stability and degradation processes of hybrid organic-inorganic perovskites. Sputtered films will be deposited on glass/ITO/charge-coupled layer samples to determine optimal deposition parameters for forming films on different substrates that will later be used for solar cell fabrication.
The surface morphology of both the targets and the resulting perovskite thin films as well as the surface and cross-section of the deposited thin films will be investigated. The roughness of the films, their composition and crystalline structure will be characterized, and the phase and orientation of the perovskite layer will be determined. The optical properties of films deposited from different targets will be determined and the energy disorder in the deposited layers will be evaluated as a function of structural properties. Taken together, the results of this work will allow us to obtain perovskite films of high optoelectronic quality and stability, as well as to understand the physical mechanisms that allow tuning their properties for rapid integration of such structures into advanced solar cells.
Project leader: Dr. Iryna Galstian
