Research Projects

Funded by the German Research Foundation
Funding period: 2022 to 2026

The self-healing of polymers has been studied intensively in recent years. In doing so, general design principles could be established enabling the preparation of healable polymers. As part of the project, these concepts are now to be transferred to functional materials. Specifically, new types of electrodes for use in organic radical batteries or (super)capacitors are to be developed, which are characterized by their ability to heal themselves.

For this purpose, self-healing polymers with various reversible groups are integrated into the electrode materials in order to ultimately enable cracks and damage to be healed. In addition to the synthesis, a focus will be on the characterization of the materials and, in particular, on the investigation of the self-healing properties. On the one hand, the cracks in the electrodes will be examined optically and tactilely, on the other hand, the restoration of functional properties, such as conductivity or capacity, will be analyzed. In particular, a new method will be established with which the healing of functional materials can be quantified in detail. Finally, the project aims to design new self-healing electrodes for applications in organic radical batteries and supercapacitors and to elucidate structure-property relationships for self-healing functional materials.

Funded by the German Research Foundation
Funding period: 2022 to 2026

Organic solar cells have been studied intensively in recent years and the achievable efficiencies have been significantly increased. However, the long-term stability of these systems is still often a challenge. In addition to the photo-oxidation of the active materials, e.g., conjugated polymers, cracks in the active material or delamination of the active layer from the electrodes also play a major role, in particular for flexible solar cells. In this context, this project of the research unit FuncHeal investigates new concepts for self-healing of photoactive materials that are suitable for organic solar cells.

Two damage scenarios will be investigated: i) Mechanical damage in the active layer (donor-acceptor blend) and ii) damage through photooxidation. Through the design and synthesis of tailor-made donor and acceptor materials (from small molecules to polymers), the introduction of flexible groups or reversible groups is intended to achieve mobility of the material on the one hand (healing of cracks) and on the other hand the introduction of reversible groups to enable the exchange of chromophores (healing after photooxidation). These processes will be examined in detail in the pure donor materials as well as in the blend with appropriately adapted acceptor materials.

Funded by the German Research Foundation
Funding period: 2022 to 2026

Die Stabilität von Polymer-Solarzellen, in denen mindestens eine Komponente der photoaktiven Schicht ein konjugiertes Polymer ist, wird oft in Abhängigkeit vom Beleuchtungsspektrum, Temperatur(zyklen), Feuchtigkeit und Einfluss von Reaktanden wie Sauerstoff und Wasser untersucht. Darüber hinaus ist eine langzeitstabile Durchmischung von Elektronen-Donatoren und -Akzeptoren wesentlich, was einer morphologischen Stabilität entspricht.

Für potentielle Anwendungen sind insbesondere die flexiblen Eigenschaften von organischen Solarmodulen wichtig, was jedoch erhöhte Anforderungen an deren mechanische Stabilität stellt. Aufgrund der in der Anwendung entstehenden Biegung von Solarmodulen können Risse in der Aktivschicht als auch Ablösungen der Aktivschicht von den Ladungsextraktionsschichten (bzw. Elektroden) entstehen. Letzteres nennt man Delamination und der Prozess tritt auf, wenn die Adhäsion zwischen zwei Schichten unzureichend ist, während Risse innerhalb einer Schicht auf eine zu geringe Kohäsion hinweisen. Projekt 4 widmet sich daher der Verhinderung von Rissen und Delaminationsdefekten, als auch deren Heilung. Hierzu werden die Materialeigenschaften gezielt manipuliert, um eine höhere mechanische Widerstandsfähigkeit zu erhalten und aufgetretene Defekte wieder auszuheilen. Die durch die mechanische Beanspruchung entstandenen Defekte werden dann durch mikroskopische und spektroskopische Methoden charakterisiert. Nach der Heilung wird analog vorgegangen, um die Heilung zu quantifizieren.

Funded by the German Research Foundation
Funding period: 2017 to 2025

Developing new degradable hydrophobic materials such as polyesterketals and polyesteramides, the project aims at designing these polymers to maximise the encapsulation efficiency for a given drug in a combined experimental and computational approach. Atomistic simulations joined with machine learning approaches along with mesoscale simulations of real nanocarrier models will be used for computationally efficient predictions of drug loading capacity, nanoparticle formation, encapsulation and drug release.

Funded by the German Research Foundation
Funding period: 2017 to 2025

Project A04 aims at establishing novel and more effective drugs for resolving inflammation, specifically of dual inhibitors of microsomal prostaglandin E2 synthase-1 (mPGES-1) and 5-lipoxygenase-activating protein (FLAP) or 5-lipoxygenase (5-LO). Improved bioavailability and target-specific delivery of the drug will be realised employing polymer particles as nanocarriers. Drug delivery at site will be investigated utilising advanced fluorescence microscopy both in monocyte-derived macrophages and more complex biosystems.

Funded by the German Research Foundation
Funding period: 2017 to 2025

We have discovered that worm-like polymer micelles are selectively taken up into the inflamed mucosa of patients with inflammatory bowel diseases. Selected modifications of the surface of these nanoparticles (e.g., by introduction of charges or targeting ligands) are expected to increase the uptake rate and enable an effective transport of anti-inflammatory drugs to local macrophages as main pro-inflammatory cells. This concept will be tested ex vivo on human macrobiopsies and in an advanced gut-on-a-chip model.

Funded by the German Research Foundation
Funding period: 2017 to 2025

By modulating the surface of polyester nanoparticles with poly(2-oxazoline)s (POx) and hybrid protein nanofibers (HPNF), the project will investigate the influence of these attached materials on the internal structure of the nanoparticle core through assessment of the thermal and mechanical properties. Depending on their structure and functionality, the POx and HPNF will also induce stealth or barrier breaking properties to the nanoparticles and serve as platform for the attachment of targeting ligands.

Funded by the German Research Foundation
Funding period: 2017 to 2025

We develop polymer-based nanoparticles with improved biocompatibility capable of gene delivery into cells in culture and in vivo into blood cells. The cohesin complex was identified as a new epigenetic mediator of inflammation signaling in hematopoietic stem cells. Now, we explore the role of cohesin in inflammation memory, and we develop polymer-based therapies for transient cohesion knockdown to ameliorate inflammation-induced tissue damage by inflammation signals and aging-related inflammation memory.

Funded by the German Research Foundation
Funding period: 2017 to 2025

B02 develops strategies to target intracellular compartments that are used by pathogenic microorganisms to escape from the immune system and are difficult to be reached by antibiotics. B02 engineers polymer nanoparticles (NPs) with targeting surfaces that allow efficient uptake by macrophages. The NPs contain antimycotics that are specifically released in phagolysosomes (PLs). A compound that enhances fusion of PLs containing pathogens with PLs containing antimycotic NPs will be developed for improving therapies.

Funded by the German Research Foundation
Funding period: 2017 to 2025

Dextran derivatives and polyesters are synthesised and used as carrier materials for inhibitors that target inflammatory pathways in hepatic stellate cells to slow down the development of liver fibrosis. Advanced biophotonic imaging is utilised to characterise the inhibitor-loaded nanoparticles in cells or directly in the liver. The nanoparticle induced modulation and activation of stellate cells are also analysed through omics-methods. These joint efforts allow for novel approaches to therapeutically target hepatic stellate cells.

Funded by the German Research Foundation
Funding period: 2017 to 2025

C04 investigates the internalisation of nanoparticles into cells and tissue and their association to intracellular compartments and their interactions with membranes. For this purpose, a combination of electron microscopy and high-resolution fluorescence microscopy techniques are utilised. Co-localisation of inflammatory markers, enzymes and receptors in the cellular context in response of particle uptake and drug release is used to obtain a deeper inside into the mode of action of nanoparticle formulations in the biological context.

Funded by the German Research Foundation
Funding period: 2021 to 2025

The liver plays a key role in the progression from uncomplicated infection to sepsis. Cross talk between parenchymal and immune cells is a key event in infection-driven liver dysfunction, and chemotactic factors including Cxcl-2 are responsible for the reorganisation of immune cells during the hyper-inflammatory response. We aim at promoting resolution of inflammation by targeting the cross talk using innovative, nanoparticle-mediated delivery of CRISPR / Cas9 machinery preventing massive immune cell recruitment.

Funded by the German Research Foundation
Funding period: 2021 to 2025

We will create a toolbox for the preparation of drug loaded virus-like nanoparticles with the potential of an easy adoption to different viruses. The aim is to deliver the antiviral drugs specifically into potentially virus-infected cells and tissue and to fight future pandemic incidences fast and efficiently. We will use spike proteins as targeting moiety on the virus-like nanoparticles and compare their uptake mechanism to wild-type and non-infectious virus-like particles, both for human SARS-CoV-2 in cell systems and murine hepatitis coronavirus in organisms.

Funded by the German Research Foundation
Funding period: 2021 to 2025

Influenza A viruses and SARS-CoV-2 cause global health problems. Establishes factors involved in viral replication, antiviral defence or inflammation are considered attractive targets for pharmaceutical treatment strategies. We will design tailor-made nanoparticles for compounds with limited cell-permeation. We will use an available and highly scalable synthetic antiviral drug, a natural anti-inflammatory drug, or inhibitors for viral uptake and viral uncoating. These nanoparticles will be characterized for their functionality in cellular systems.

Funded by the German Research Foundation
Funding period: 2021 to 2025

Funded by the German Research Foundation
Funding period: 2017 to 2025

Z01 is a platform that supports and develops dedicated measurement possibilities to address important questions of the CRC. The support and developed methodological areas include: High-throughput experimentation, upscaled synthesis of polymers, solution characterisation by hydrodynamics, fractionation, light scattering, image-based characterisation, supply of human monocyte-derived macrophages, as well as formulation procedures that satisfy the requirements of a good manufacturing practice (GMP).

Funded by the German Research Foundation
Funding period: 2017 to 2025

Funded by the German Research Foundation
Funding period: 2017 to 2025

Funded by the German Research Foundation
Funding period: 2017 to 2025

Fluid flow and reactive transport in the Hainich CZE environment take place in a complex structured hydrogeological setting. In order to reconstruct migration pathways of natural organic matter, tailored conservative and reactive tracers, which act as functional analogues, are required. This project will create a tracer library based on methacrylic copolymers with controlled colloidal size, hydrophobicity, pH- and redox-dependent behavior, as well as controlled stability. These tracers are then fully characterized and utilized in model solubility and mobility assessments of increased complexity from the lab-scale to field testing in view of a full scale application.

Funded by the German Research Foundation
Funding period: 2021 to 2024

Funded by the German Research Foundation
Funding period: 2022 to 2024

The interaction of transition metal ions and organic molecules in solution will be investigated using a machine-learning approach. So far, openly reported systematic massive data on these systems are sparse, preventing from an efficient use of machine-learning approaches. Within this project, we address this challenge by generating high throughput data, both experimentally, employing modern robot-based approaches, and theoretically, by utilizing DFT calculation on fast GPU-based DFT programs.

Within this project, we will not only generate large amount of data (experimentally and theoretically), which can be individually utilized employing methods of machine-learning to identify correlations but, moreover, to also cross-correlate theoretical and experimentally obtained data.

The aim of this systematic study is to predict the interaction of an organic molecule and a metal ion by just using the chemical structure of the molecule and the sort of metal ion. These results could therefore be highly interesting for the development of new drugs, catalysts or energy conversion moieties.

Funded by Thüringer Aufbaubank (TAB)
Funding period: 2021 to 2023

Funded by Thüringer Aufbaubank (TAB)
Funding period: 2021 to 2023

Funded by the German Research Foundation
Funding period: 2021 to 2023

In the proposed joint project between the two groups from polymer chemistry (Schubert) and polymer physics (Tsvetkov) the preparation of charged side-chain metallopolymers and their molecular and conformational analysis in solution is targeted. The applicants aim for a fundamental understanding of how the various structural parameters of the metallopolymers (nature of the metal center, presence of charges, counterions, etc.) contribute to their solution properties. For this purpose, three different types of metallopolymers will be in focus of interest: Metallopolymers with pending terpyridine complexes, metallocene/metallocenium sites and metal-carbonyl complexes. Such polymers are of significant importance regarding, for instance, (photo)catalytic, optoelectronic, nanotechnological or biomedical applications. However, in-depth investigations correlating their performance to their molecular and conformational structure have not yet been made. The modularity of synthesis, combining controlled radical polymerization techniques and metal-to-ligand coordination chemistry, will allow an accurate preparation of a systematic set of metallopolymer libraries (Schubert group) required for the analysis by the various hydrodynamic and optical methods available in the Tsvetkov group. The applicants have agreed cooperation with two external partners to further utilize the synthesized metallopolymers to fabricate bimetallic nanoparticles for data-storage applications (Wong group, Hong Kong, P.R. China) and as photoactive antimicrobial metallodrugs (Schatzschneider group, Würzburg, Germany).Finally, interpolyelectrolyte complexes, the supramolecular associates of the prepared polycationic metallopolymers and natural or synthetic polyanions, will be assembled and characterized accordingly.

Funded by the German Research Foundation
Funding period: 2021 to 2023

Metallopolymers represent a special class of supramolecular polymers, which consists of two different building blocks. Metal complexes and (synthetic) polymers are combined into one material featuring properties of both. This concept should be further explored within the current project. Thus, new kinds of metallopolymers will be synthesized featuring a superior self-assembly behavior and, based on this defined nanostructure formation, novel extraordinary properties. For this purpose, metal complexes based on terpyridine as ligand with a tendency to form defined molecular assemblies will be combined with selected polymeric backbones in order to trigger superior assembly processes of the resulting metallopolymers, potentially providing new or advanced properties and applications of such materials, e.g., self-healing or shape-memory behavior. To obtain superstructures as well as structure-property relationships, the self-assembly process of the metal complexes should be combined with polymers also featuring self-assembling nanostructures (e.g., crystalline polymers, phase-separation block copolymers). A central target will be the elucidation and control of the interplay of both interactions and whether this is beneficial or disadvantageous to the overall assembly behavior. A main challenge of the project will be the characterization of the obtained materials in solution as well as in the solid state. For this purpose, a range of different state-of-the-art techniques will be applied in order to visualize the obtained structures of the metallopolymers as well as to understand the influence of the metal complex(es) on the polymer behavior and vice versa. The latter one is in particular interesting for potential applications of the metallopolymers. Thus, the stimuli-responsive behavior of these new kind of materials will also be studied in the current project.

Funded by the Federal Ministry of Education and Research
Funding period: 2021 to 2023

Funded by the Federal Ministry of Education and Research
Funding period: 2021 to 2023

Funded by the Carl-Zeiss-Stiftung

Funded by the German Research Foundation
Funding period: 2020 to 2023

This project will pursue the implementation of nanodiamonds (NDs) towards enhancement of properties (chemical, electrical, opto-electronic) of organic photovoltaic (PV) solar cells. Structures prepared with NDs will be either layers (e.g. via extending or replacing charge extraction layers such as PEDOT:PSS or ZnO) or bulk (ternary bulk heterojunction system of organic solar cells). NDs will vary in size (1-10 nm) and surface termination (O, H), all very well defined by preparation. The structures will be characterized by advanced scanning probe methods (KPFM, C-AFM) in the dark and under illumination (DUV-vis, sol. simulator) and macroscopic (e.g. current-voltage) characterizations. Physicochemical interactions between NDs and other charge transport or charge generation materials will be monitored spectroscopically (Raman scattering, FTIR, PL). It is expected, that the project will enhance the knowledge on the role and possible application of NDs in organic photovoltaics (light scattering, active photoresponse, optical and chemical interaction, charge extraction and transport) and which configuration (size and termination of NDs, layered or bulk, type of photovoltaic blend) will exhibit the best development output in terms of performance and stability (power conversion efficiency, optical and mechanical properties, degradation).

Funded by the German Research Foundation
Funding period: 2020 to 2023

Dentistry uses durable and very stable bondings and composites. In temporary applications (for example, in the attachment of brackets or temporaries) thereby a tooth substance gentle removal is not possible so far. The aim of the project is to produce new formulations, which can still be cured by means of light (> 420 nm), but can be weakened so much by irradiation with UV light (<360 nm) that a gentle removal of the brackets and composites is possible. For this purpose, new photocleavable components are synthesized and formulated into bonds and composites. By varying the concentration of the constituents of the formulations (in the formulation robot), their curing and subsequent UV irradiation, as well as the determination of the change in the mechanical properties (by means of nanoidentation), formulations are identified which are subjected to more thorough tests. This includes determination of biomechanical limits and shear bond strength to teeth and analysis of tooth surfaces after detachment, as well as examination of the biocompatibility of the formulations and their degradation products.

Funded by the German Research Foundation
Funding period: 2020 to 2023

Amongst the different energy storage systems/batteries, polymer-based batteries represent an emerging technology. They feature interesting properties like lightweight, printability, flexibility as well as charging within few minutes (down to even seconds). Such polymer-based batteries can be fabricated utilising organic materials without the requirement for other critical raw materials. The well-defined structure of organic/polymer materials offers reliable structure-property relationships, and, thus, a well controllable and tuneable electrochemical behaviour can be achieved. The Priority Programme aims at the elucidation of structure-property-relationships, the design and synthesis of novel active materials, which will result in polymer-based batteries with preferably high capacities and longer lifetime over many cycles.

Funded by the German Research Foundation
Funding period: 2020 to 2023

Funded by the German Research Foundation
Funding period: 2020 to 2023

Funded by the German Research Foundation
Funding period: 2020 to 2023

Funded by the German Research Foundation
Funding period: 2020 to 2023

Funded by the Thüringer Ministerium für Wirtschaft, Wissenschaft und Digitale Gesellschaft (TMWWDG)
Funding period: 2020 to 2023

Funded by the European Union
Funding period: 2019 to 2023

Funded by the Federal Ministry of Education and Research
Funding period: 2021 to 2022

Funded by VolkswagenStiftung
Funding period: 2021 to 2022

Quorum sensing is a phenomenon of unicellular organisms to induce a different response depending on their population density. Only to name two natural examples, quorum sensing is the basis of biofilm formation of some bacteria or the bioluminescence of squids, which have a larger number of symbiotic bioluminescent bacteria in specialized light organs. Noteworthy, these bacteria will not glow isolated. In this project the biological principle of quorum sensing is intended to serve as an inspiration for the design of a new generation of synthetic polymeric materials. These polymers will feature different properties based on their concentration or number. They can "communicate" amongst each other and certain functions or properties of the material are only enabled as soon as sufficient particles are spatially close to each other. This behavior will enable the design of the next generation of intelligent materials.

Funded by the Thüringer Aufbaubank (TAB)
Funding period: 2021 to 2022

Funded by the Thüringer Aufbaubank (TAB)
Funding period: 2020 to 2022

Funded by the Thüringer Aufbaubank (TAB)
Funding period: 2020 to 2022

Funded by the Federal Ministry of Food and Agriculture (BMEL)
Funding period: 2019 to 2022

By means of digital sensor technology, almost all vitality parameters of a cow or a bovine can be determined and monitored in real time today. These are, for example, body temperature, blood pressure, pulse and heart rate, blood oxygen saturation, motion parameters or the amount of feed and water intake. This allows irregularities in the daily routine to be detected, conclusions to be drawn about the health of the animals, or animal-specific decisions to be derived when managing the animals. What fitness trackers can do for humans today can thus be used in a very similar way for animal welfare.

In the “Sensors & Energy Supply” field of experimentation, such sensor systems are examined from the point of view of their general usability by farmers. Which sensor technology is suitable for use on animals and where are the limitations and boundaries? Which parameters can be collected with which sensor at which position and how often is this actually necessary? By which energy supply can the sensor technology be fed more persistently or sustainably? After all, those sensors require energy and an animal cannot be regularly plugged into a socket like a cell phone. In the end, of course, it all has to pay off financially, which makes the task correspondingly more difficult.

These and other questions are being experimentally investigated and scientifically evaluated not only for products that are currently commercially available on the market, but also for novel sensor, as well as energy generation, storage and saving technologies. The answers to be found will be processed during the course of project for both, research and practical users. The answers may also represent an important decision-making aid for the introduction of digitalization in animal-related agriculture.

Funded by the Thüringer Aufbaubank (TAB)
Funding period: 2019 to 2022

Funded by the German Research Foundation
Funding period: 2019 to 2022

The balance of microbial consortia with other organismic partners and the environment is critical for the functioning of all ecosystems, climate stability, sustainable agriculture, and the well-being of plants, animals and humans. We define a Microverse as functionally interacting or spatially coexisting microbial consortia. Anthropogenic impact or infectious microorganisms can dramatically dysbalance a Microverse resulting in the deterioration of ecosystems, weather extremes, severe crop losses or disease. Targeted interventions aim to restore the original state or establish alternative states of balance. Typically, we attempt to remedy non-functional systems by treating the symptoms, because the molecular mechanisms leading to a microbial balance are largely unknown. The Microverse Cluster will address this shortcoming by answering the following research questions: What defines the dynamics of microbial balance? Which factors disturb the equilibrium, and how is re-balancing attained? How can we shape and control microbial consortia to create beneficial impact?We will combine our expertise in microbiology, chemical biology, infection biology, optics/photonics, materials science and bioinformatics/systems biology at the university and non-university institutes. The Microverse Cluster will activate the synergistic potential of four Collaborative Research Centers, an Excellence Graduate School and additional high-ranking coordinated research programs. This is further complemented by our industry partners.The Microverse Cluster is organized into three Research Areas: A Microverse of the EnvironmentB Microverse of the HostC Data Synopsis and Microverse Imaging Center.These Research Areas address the orchestration of microbial balance on multiple levels by chemical signals, host factors, spatial demand, metabolic fluxes and genetic exchange. The cross-system comparisons and mining of data from diverse settings such as infection of human and plant hosts, confined and unconfined aqueous environments as well as synthetic microbial communities will lead to the identification of general principles.A new building providing space for an existing and new professorships and junior research groups will form a center of gravity, facilitating scientific exchange and integrating international guests. It will also be home to a Microverse Imaging Center with state-of-the-art biophotonics technologies and dedicated facilities for prototype development and field applications. We will instate a flexible funding scheme to promote cooperative research, individual fellowships and structured research training programs. Internationalization and diversity management will promote strategic networking as well as contributing to the global visibility of this unique Microverse Cluster. By learning from nature, the Microverse Cluster will offer innovative solutions for fighting disease and environmental dysbalance.

Funded by the German Research Foundation
Funding period: 2019 to 2022

This research proposal is dedicated to create artificial molecular photosystems and to explore their potential in energy conversion schemes. In order to reach this goal, a modular toolbox-approach will be followed, which previously testified a significantly reduced synthetic effort. The desired function is based on the disconnection of elementary steps (energy- and electron transfer) by tailored building blocks – which enable the guided development of polymer-based architectures. The choice and selection of the many conceivable structures originates from the inherent optical and electrochemical properties, which are to be combined in due course. The light-induced charge separation is of key importance albeit the assembly strategy can be adapted to the needs of other fields of applications. In the first work package, the constitutional building blocks will be synthesized, which differ in their molecular structure. Moreover, polymerizable groups as well as solubility-promoting groups will be introduced, which are required in the following packages.In the second work package, molecular architectures are to be assembled via polymerization of electrochemically active building blocks. The obtained electron- and hole-transporting polymers will be attached t in the final two steps to a dye unit. Noteworthily, the facile modular synthesis of substance libraries is ensured, which is synthetically very demanding in case of related molecular assemblies following a classical approach. In the third work package, the light-induced charge separation and recombination thereof is to be explored using time-resolved spectroscopy. Hence various molecular parameters will be explored (e.g. chain length, kind of conjugation, internal charge cascades), in order to minimize the recombination. The studies embark from investigation in solution towards the solid state via film formation, in order to evaluate the potential for descending projects and proposals.The aim and benefit of this research project is to establish a modular platform on a molecular level, in order to create and to control electric charges and excited states on a nanoscopic level. Such control is relevant for many applications of energy conversion, e.g. coupled catalytic reactions, molecular motion, or to generate an external electrochemical potential. Noteworthily, the modular character permits the replacement of individual components by better-suited ones in a straight forward fashion, which is desirable also for the design of other molecular architectures and founds the basis for other applications and further descending projects.

Funded by the German Research Foundation
Funding period: 2019 to 2022

The design of selective anion binding sites, which enable a detection, binding and transport of relevant anions, is one of the most important fields in supramolecular chemistry. While anion detection based on hydrogen bonds is well established, the potential of halogen bonds for selective anion recognition was only realized very recently. In contrast to the hydrogen bond, the strongly related halogen bond exhibits a stronger orientational preference, a higher covalent contribution to the binding as well as a stronger interaction with a Lewis-basic partner, which enables the construction of highly selective anion binding sites.Halo-1,2,3-triazoles and halo-1,2,3-triazoliums feature highly Lewis-acidic halogen atoms that are capable of establishing strong halogen bonds. Owing to the facile and modular synthesis of these heterocycles, the halogen bond can be readily implemented into a variety of different systems. The research described in this proposal aims at exploiting the great potential of halogen bonds by making use of the facile and modular synthesis of halo-1,2,3-triazoles and halo-1,2,3-triazoliums. In more detail, the following sub-projects (1 to 5) will be investigated: 1) By the help of specific modifications on the anion binding site, the effect of different parameters, namely the bite angle to the anion, the spacer between the halogen-bond donors the electron-withdrawing group as well as the preorganization of the system, will be studied.2) By combining a ruthenium(II) complex with an anion binding side, selective anion sensors with low detection limits will be constructed.3) By exploiting cooperative effects, ion-pair receptors that exhibit high selectivity and binding strength for different ion pairs will be designed. 4) The higher directionality as well as the higher anion affinities of halogen bonds relative to analogous hydrogen-bond-based systems is expected to enable the design of highly efficient organo-catalysts. The modular synthesis of halo-1,2,3-triazoles allows a simple integration of chiral moieties, which, in turn, allows the construction of highly interesting catalysts for enantioselective reactions. 5) Since halogen bonds are strong but labile, the potential application in self-healing materials is planned.The application of the halogen bond for anion recognition is currently a hot topic and offers an immense potential. This research described herein aims at developing new halogen bond donors in order to design new anion sensors, organo-catalysts as well as functional materials.

Funded by the Federal Ministry of Education and Research
Funding period: 2019 to 2022

Funded by the German Research Foundation
Funding period: 2018 to 2022

DNA origamis will be used for the precise spatial positioning of functional moieties such as molecular compounds (e.g. dyes, photosensitizers, catalysts and electron relays) as well as functional copolymers. We will elucidate structure-property relationships in these assemblies and study energy/electron transfer processes. Precise assembly of two molecular entities on the surface, assembly of molecular moieties next to copolymers, two functional copolymers, which are assembled in close proximity as well as the surface-routing of single functional moieties is developed.

Funded by the German Research Foundation
Funding period: 2018 to 2022

The project aims at the integration of photoredox-active ruthenium photosensitizers into redox-active copolymers by supramolecular interactions, e.g. ionic interactions or π-stacking. Redox-active moieties such as anthra¬chinones and viologens will be embedded within the polymer and can act as multi-electron storage components to accept electrons transferred by the photosensitizer. Further functionalization of the polymer by metal complex HER catalysts will be used to harvest the stored electron for subsequent catalytic turnover. The influence of the copolymer structure on the electron transfer between photosensitizer – electron relay – catalyst will be investigated in detail.

Funded by the German Research Foundation
Funding period: 2018 to 2022

Redox flow batteries (RFBs) are interesting candidates for stationary energy storage. Their capacity and power can be scaled independently by adjusting the size of the storage tank and the cell stack, respectively. In contrast to classical batteries, redox flow batteries (RFBs) are based on active materials, which are dissolved (suspended) in a liquid electrolyte. Consequently, the achievable energy densities are limited due to the presence of a non-active solvent (often water). The most investigated RFB is the all vanadium RFB, which utilizes vanadium ions dissolved in sulfuric acid. In recent years, the interest in organic (polymeric) active materials is steadily growing. This joined proposal aims to develop redox-active ionic liquids (IL) as new materials for the electrolytes of RFBs. All molecules present in the electrolyte will therefore be redox-active. Additionally, the limited voltage window of aqueous electrolytes will be extended. Consequently, higher energy densities will be achievable.The project will be investigated by the two partners at the Friedrich Schiller University Jena (Institute for Technical Chemistry and Environmental Chemistry as well as Institute for Organic Chemistry and Macromolecular Chemistry). Latter partner will contribute to the synthesis and structural characterization of novel redox-active ionic liquids. These ILs will comprise redox-active moieties and ionic groups. The properties will be tuned by the respective structure of the IL. Furthermore IOMC will perform the tests of the synthesized materials in test RFB cells. The ITUC will contribute to the extensive characterization of the synthesized materials. In particular the electrochemical as well as thermal properties will be of interest.

Funded by the German Research Foundation
Funding period: 2018 to 2022

Self-healing polymers are capable of restoring their original functionalities after being damaged. In particular, intrinsic self-healing polymers based on different reversible interactions have been investigated intensively. Besides different supramolecular interactions mainly reversible covalent interactions have been studied. Within this context reversible addition (e.g. Diels Alder reaction) as well as condensation reactions (e.g. imines, acylhydrazones) have been investigated. Much research was devoted to elucidate the healing process and the underlying healing mechanism, respectively, of different reversible polymer networks. Despite the significant knowledge gained, the damage event as well as the results of the damage (besides an obvious scratch/crack) remain uncertain. Consequently the question arises: 'Are the reversible covalent bonds really predetermined breaking points?'Within this context this project aims at the elucidation of the occurring processes in reversibly crosslinked polymers by the introduction of mechanophores. These mechanophores will be based on donor-acceptor systems, which will be incorporated into reversible covalent bonds (thiol-ene reaction, Diels Alder cycloaddition, imines). The nature of the reversible bond (open or closed) will result in a shift of the UV vis absorption allowing the monitoring of this bonds. By this manner first the damage process can be investigated, subsequently, the healing of this polymer networks can be monitored. Consequently, the nature of the damage in connection with the mechanical activation of the polymer, i.e. of the reversible bonds, will be investigated. Different damage scenarios might lead to different activation patterns within the polymer network and consequently in differences in the healing. Noteworthy, this mechanophores will also allow a detailed study of imines, which will show a healing process based on exchange reactions. Most molecular characterization techniques will not reveal much details in case of exchange reactions (in comparison to a full opening of the reversible binding units).

Funded by the German Research Foundation
Funding period: 2018 to 2022
Project of the SPP 2102:  Light Controlled Reactivity of Metal Complexes

The proposed joint project between two groups from synthetic and physical chemistry targets the investigation of ultrafast excited-state processes in tri- and oligonuclear complexes incorporating Ru(II), Fe(II), Os(II) and Cr(III) centers upon excitation of the metal-to-ligand charge-transfer. Up to now mainly the excited-state relaxation dynamics of tri- and oligonuclear complexes under low-intensity excitation have been reported. In this study, however, the regime of high-excitation intensities will be employed. For the first time, a systematic study in this regime will be performed to derive detailed structure-dynamics relationships. The project will address central questions associated with the excited-state properties of multiply excited oligonuclear complexes, e.g., if the concept of exciton-exciton annihilation, as known from the photophysics of conjugated polymers, can also be translated to molecular coordination compounds and how its kinetics can be tuned by complex design. Moreover, the details of kinetically hindered intramolecular energy transfer will be exploited – a process recently reported process in an exemplary trinuclear donor-acceptor-donor system. The main theme of the proposed project is related to the development of photoinduced multi-electron processes and the understanding as well as the design of excited states in tri- and oligonuclear metal complexes. In continuation of the joint preliminary work, mixed-metal complexes with -conjugated bisterpyridine ligands will be employed as building blocks and investigated regarding a number of mechanistic aspects: How far does the molecular design effect the triplet-triplet excited-state annihilation upon photoexcitation of two distinct metal centers within a single molecular assembly? Can the molecular design be utilized to manipulate the rate of kinetically hindered intramolecular energy transfer within trinuclear donor-acceptor-donor complexes? How are the aforementioned processes affected if the number of donor units within the extended complexes is increased (given that more than a single donor site is excitated)?

Funded by the German Federal Ministry for Economic Affairs and Energy
Funding period: 2017 to 2022

Funded by the Federal Ministry of Education and Research
Funding period: 2018 to 2021

Funded by the Thüringer Aufbaubank (TAB)
Funding period: 2018 to 2021

Funded by the Thüringer Aufbaubank (TAB)
Funding period: 2018 to 2021

Funded by the Thüringer Aufbaubank (TAB)
Funding period: 2018 to 2021

Funded by the German Research Foundation
Funding period: 2017 to 2021

Natural materials can feature a large variety of different interesting properties. Those properties are often associated with a predefined protein structure. The basic information for the fabrication (biosynthesis) of such highly ordered molecules is encoded in the DNA. The process called protein biosynthesis enables the synthesis of these proteins in a controlled manner for a certain purpose.This proposal aims to mimic the concept of the protein biosynthesis in the preparation of structurally defined ligand containing polymers as well as their corresponding metallopolymers. For this purpose, ligand-containing templates will be prepared, which represent the encoded information. A highly selective and orthogonal binding event would result in preorganized systems allowing the preparation of ligand-containing oligomers. Those moieties can later easily be transferred into polymers using either a step-growth or a chain-growth polymerization technique. Finally, the complexation with different metal salts will result in the formation of metallopolymers featuring a high degree of organization within the resulting macromolecule. The obtained polymers should be studied in detail. A particular focus will be the molecular structure and, furthermore, the organization within the metallopolymers. Finally, this analysis should enable to elucidate structural-property relationships and should direct to a new and advanced preparation methods of metallopolymers.

Funded by the German Research Foundation
Funding period: 2016 to 2021

Within the project three-dimensional hydrogels will be synthesized by two-photon polymerization (2PP) in order to generate structured 3D networks which allow to selectively influence interactions of cells with the surfaces. For this reason, poly(2-oxazoline)-based macromonomers have to be synthesized as educts for the production of 3D scaffolds by 2PP. To enhance structuring process and properties of the hydrogels water soluble and biocompatible photoinitiators will be synthesized by coupling of known photoinitiator motives to oxazoline based polymers and oligomers. Subsequently, covalent attachment of additional functionalities for the enhancement of the adhesion of cells to the scaffolds is foreseen. The capacity of the generated scaffolds to induce certain processes of cell differentiation in dependency of their 3D structure will be evaluated using different mesenchymal stem cells.

Funded by the German Research Foundation
Funding period: 2016 to 2021

The growing interest in mobile devices and their increasing integration into the World Wide Web (Internet of Things) necessitates the availability and development of small and flexible energy-storage systems. However, lithium ion batteries, which represent the current benchmark technology, do not allow the assembly of flexible batteries and demand environmentally questionable techniques for production and processing of raw materials as well as for the final disposal of disused devices. Hence, current research focuses more and more on thin film batteries that are based on organic redox active molecules, which are prepared through organic synthesis and disposed free of residues via burning. Furthermore, their (electro)chemical properties can be easily tuned through choosing a suitable chemical structure. Unfortunately, small molecules tend to dissolve in the used electrolyte leading to a significantly decreased lifetime of the battery. Thus, the monomeric redox active units are integrated into long chain polymers, which possess a substantially decreased solubility.In the course of the project, in particular polymers that are based on the benzo-1,2,4-triazinyl radical are developed. This molecule features electrochemical reversibility, high stability against air and moisture, as well as facile synthetic accessibility. Its redox characteristics can be, furthermore, easily tuned through the molecular substitution pattern, which enables even the preparation of systems that can serve both as anode and cathode material, allowing the construction of bipolar, i. e. poleless, batteries.The increase of the batteries still low theoretical capacity (from around 60 to over 100 mAh g-1) represents a central goal, which should be mainly achieved through the reduction of the molar mass of the monomer. (Electro)chemical stability, cell voltages of around 1.2 V (to allow for aqueous electrolytes), and polymerizability of the molecule have to be maintained, which is ensured through the investigation of structure-property relationships in the course of substituent variations to enable a systematic optimization of the system. The characterization process comprises the preliminary characterization of the monomeric and polymeric compounds in solution and in the solid state, the processing of the polymers with conductive additives and binder materials toward thin film composite electrodes and their subsequent characterization, as well as the assembly and comprehensive investigation of half-organic (using lithium or sodium as anode material) and full organic cells. Furthermore, the preparation of the batteries is optimized, in particular with regard to the used additives and the thin-film processing (doctor blading, inkjet printing).

Funded by the Thüringer Aufbaubank (TAB)
Funding period: 2018 to 2019

Funded by the Thüringer Aufbaubank (TAB)
Funding period: 2017 to 2019

Funded by the German Research Foundation
Funding period: 2016 to 2019

The project targets the integration of molecular compounds, i.e. photocatalysts and redox-active antenna dyes, into recently developed carbon nanomembranes for applications in, e.g., photocatalytic cells. This research on novel photoactive membranes for artificial photosynthesis will comprise different tasks from materials and physical chemistry: (i) development of novel carbon nanomembranes functionalized with benchmark electron donors, acceptors and photosensitizers; (ii) development of novel synthetic procedures for the fabrication of carbon nanomembranes with new functionalities, i.e. photosensitizers and electron donors/acceptors integrated within the membrane plane; (iii) developing a mechanistic understanding of light-induced elementary processes within the novel carbon nanomembranes and proof-of-concept photocatalytic hydrogen evolution from carbon nanomembranes functionalized with cobaloxime proton-reduction catalysts. The project aims at establishing the conceptual basis for the design of novel photoactive membranes for artificial photosynthesis. The supramolecular systems to be researched are based on molecularly thin carbon membranes, which can be specifically functionalized on either side of the membrane. In this project the focus will not (yet) be on device integration but on establishing the basic design principles and performing essential mechanistic studies on the elementary reaction steps underlying a potential use of the systems in photocatalytic water splitting. The carbon nanomembranes will be functionalized with Ru(II)-polypyridine-derived systems, which act both as the chromophores, i.e. the light-absorbing units, and the primary electron donors. In the envisioned design of the photoactive carbon nanomembranes the electron donors will be grafted onto one side of the molecularly thin membranes, while the opposite side of the membrane will be functionalized orthogonally by the corresponding acceptor units. Thereby, the formation of charge separated states is expected upon irradiation, whereas the photooxidized and photoreduced species are spatially separated by the nanomembrane. In order to enhance the lifetime of the charge separated state, and hence the 'usability' the photoseparated charges, we will adopt concepts from the design of molecular triads (i.e. acceptor-chromophore-donor) and design systems, in which the chromophore-side of the membrane is additionally equipped with electron donor units.

Funded by the Federal Ministry of Education and Research
Funding period: 2016 to 2019

Funded by the German Research Foundation
Funding period: 2016 to 2020

Shape-memory polymers are able to recover their original shape after preceded deformation. Upon an external trigger (e.g., heat) the polymer will return from the temporary shape into its initial shape. Metallopolymers are suitable candidates for the design of novel shape-memory polymers, which can be considered as the missing link between the established shape-memory polymers and shape memory alloys. Shape-memory metallopolymers are on-demand switchable shape-memory polymers. Due to the integrated supramolecular interaction (i.e. the metal-ligand-interaction) the reversibility (from low to high) as well as the suitable trigger (e.g., temperature, chemicals and redox reactions) can be tuned. Within the project, new metallopolymer networks with different metal ions (i.e. different potential triggers) and comonomers will be prepared. Within this context, two different processing methods will be utilized, i.e. reactive inkjet printing as well as copolymerization in bulk. The resulting metallopolymers will be investigated regarding their shape-memory behavior and the possibility to trigger the materials with different external stimuli like heat, light or chemicals. Furthermore, the influence of the chosen metal salt on the resulting properties as well as the addressability by the different stimuli will be studied in detail. This basic information will later be utilized for the design of novel triple-shape memory metallopolymers. For this purpose, two different types of metal complexes are required, which can be triggered independently from each other. Thus, one metal complex can be triggered to obtain a transition from the first temporary shape to the other one. Finally, the other metal complex will be addressed by the same stimulus at other conditions (e.g., higher temperature) or by the utilization of a complete different stimulus (e.g., heat and light) resulting in the final permanent shape. In another part of the project the self-healing ability of the shape-memory metallopolymers will be studied. In this context, the influence of the shape-memory behavior on the self-healing behavior will be studied and will also be compared to the classical self-healing metallopolymers. Thus, it will be investigated if there is a shape-memory assisted self-healing (SMASH). Finally, a completely new shape-memory behavior will be studied, which is the multiway triple shape-memory behavior. For this purpose, a metallopolymer with two independently addressable metal complexes is required. Furthermore, two different stimuli have to be utilized. In contrast to classical triple shape-memory polymers this new behavior offers the possibility to have two different temporary shapes after the applying of the first external stimulus depending on the order of the utilized stimulus. Thus, if light is applied first a completely different shape will be obtained. Finally, if the other stimulus is also used the permanent shape will be obtained.

Funded by the Thüringer Ministerium für Wirtschaft, Wissenschaft und Digitale Gesellschaft (TMWWDG)
Funding period: 2014 to 2019

Funded by the German Research Foundation
Funding period: 2016 to 2020

The aim of this project is the preparation of wormlike micelles with controlled length, stability, and composition for selective uptake into breast cancer cells via multivalent targeting. This is realized through the synthesis of amphiphilic polyether- and polyester-based block copolymers with varying weight fractions and crosslinkable units in the side chain of the hydrophobic segment. Further, differently functionalized derivatives of 2,5-anhydromannitol (AMtl) will be synthesized and covalently attached to the hydrophilic block using suitable conjugation reactions. AMtl features a high affinity to a fructose-selective transporter, GLUT5, which is known to be overexpressed in many breast cancer cell lines. Subsequent co-assembly strategies using different block copolymer mixtures with varying content of AMtl-units allow then the preparation of wormlike micelles with controllable density of AMtl within the micellar corona. Depending on length and flexibility of such nanostructures, several GLUT5-receptors on the surface of such cells can now be addressed simultaneously. In that way, we aim at a higher specificity of wormlike micelles if compared to spherical analogues with regard to the targeted breast cancer cell lines. Within the framework of this project, we will also investigate the influence of micellar stability (e.g., mediated using core crosslinking) on cell uptake via endocytosis under static and dynamic conditions. As an alternative to core-crosslinking, we will also employ hydrolytically sensitive polyester blocks as core-forming segments.

Funded by the Carl Zeiss Foundation
Funding period: 2017 to 2019

Funded by the Thüringer Ministerium für Umwelt, Energie und Naturschutz (TMUEN)
Funding period: 2018

Funded by the German Research Foundation
Funding period: 2016 to 2018

The design of selective anion binding sites, which enable a detection, binding and transport of relevant anions, is one of the most important fields in supramolecular chemistry. While anion detection based on hydrogen bonds is well established, the potential of halogen bonds for selective anion recognition was only realized very recently. In contrast to the hydrogen bond, the strongly related halogen bond exhibits a stronger orientational preference, a higher covalent contribution to the binding as well as a stronger interaction with a Lewis-basic partner, which enables the construction of highly selective anion binding sites.Halo-1,2,3-triazoles and halo-1,2,3-triazoliums feature highly Lewis-acidic halogen atoms that are capable of establishing strong halogen bonds. Owing to the facile and modular synthesis of these heterocycles, the halogen bond can be readily implemented into a variety of different systems. The research described in this proposal aims at exploiting the great potential of halogen bonds by making use of the facile and modular synthesis of halo-1,2,3-triazoles and halo-1,2,3-triazoliums. In more detail, the following sub-projects (1 to 5) will be investigated: 1) By the help of specific modifications on the anion binding site, the effect of different parameters, namely the bite angle to the anion, the spacer between the halogen-bond donors the electron-withdrawing group as well as the preorganization of the system, will be studied.2) By combining a ruthenium(II) complex with an anion binding side, selective anion sensors with low detection limits will be constructed.3) By exploiting cooperative effects, ion-pair receptors that exhibit high selectivity and binding strength for different ion pairs will be designed. 4) The higher directionality as well as the higher anion affinities of halogen bonds relative to analogous hydrogen-bond-based systems is expected to enable the design of highly efficient organo-catalysts. The modular synthesis of halo-1,2,3-triazoles allows a simple integration of chiral moieties, which, in turn, allows the construction of highly interesting catalysts for enantioselective reactions. 5) Since halogen bonds are strong but labile, the potential application in self-healing materials is planned.The application of the halogen bond for anion recognition is currently a hot topic and offers an immense potential. This research described herein aims at developing new halogen bond donors in order to design new anion sensors, organo-catalysts as well as functional materials.

Funded by the German Research Foundation
Funding period: 2016 to 2018

The goal of the ASYMCOPO project is to develop new materials that mimic the useful properties of gradient copolymers, but which do not require complex synthetic procedures for their preparation. Gradient copolymers, whose composition varies continuously as a function of chain length, are an intriguing class of materials with many potential applications, including as shock- and noise-absorbers and as interfacial stabilizers. However, the preparation of a polymer with a pre-defined gradient of composition requires a semi-continuous process with careful control over monomer addition and constant feedback in order to regulate the composition at each stage of the polymerization. It has recently been noted that the very idea of a gradient copolymer is something of a contradiction in terms: while the average composition of all the chains of a polymer may vary smoothly from one end of the chain to the other, each individual chain is composed of discrete monomer units, and at any point in the chain the composition must take one of only two possible values. Thus, polymers which, on average, exhibit a composition gradient contain a broad distribution of structures. Furthermore, it is impossible to reconstruct the composition gradient of the entire polymer from a single polymer chain. It is thus natural to ask, what is the defining structural feature of a gradient copolymer? And can these properties be mimicked using structures that are easier to prepare, using well-understood batch polymerization processes? In the ASYMCOPO project we aim to answer this question by introducing the concept of asymmetric copolymers: polymers that are intermediate in structure between block and random copolymers. We have developed a framework for the classification of this class of polymers, centered on the concept of a moment of asymmetry, which we will use to guide our research in first synthesizing, then exploring the properties of this new class of materials. In particular, we seek to define structures consisting of 2, 3, or 4 random copolymer segments which mimic the useful properties of gradient copolymers, but are substantially easier to synthesize. This project requires the preparation of an extensive library of copolymers of different structures, and hence necessitates the involvement of a laboratory with expertise in high-throughput polymer synthesis and characterization. The Institute for Organic and Macromolecular Chemistry (IOMC), in Jena, Germany, is the European leading research group in this domain. In parallel, synthesis of well-defined gradient copolymers requires careful control of polymerization conditions, employing the expertise of the Laboratoire des Intéractions Moléculaires et Réactivité Chimique et Photochimique (IMRCP) laboratory of Toulouse, France, in polymerization kinetics, polymer synthesis and characterization.

Funded by the Thüringer Aufbaubank (TAB), Co-financed by the European Social Fund (ESF)/European Regional Development Fund (ERDF)
Funding period: 2016 to 2018

Funded by the Thüringer Aufbaubank (TAB)
Funding period: 2016 to 2018