Quantification of dynamic ion correlations in highly concentrated liquid electrolytes and of their implications for charge- and mass transport

43,000 students and 8,000 employees in teaching, research and administration, all working together to shape perspectives for the future – that is the University of Münster. Embedded in the vibrant atmosphere of Münster with its high standard of living, the University’s diverse research profile and attractive study programs draw students and researchers throughout Germany and from around the world.

In the group ‘Polymers and Nanostructures’ at the Institute of Physical Chemistry of the University of Münster we are seeking a

Doctoral Researcher (m/f/d) within the project ‘Quantification of dynamic ion correlations in highly concentrated liquid electrolytes and of their implications for charge- and mass transport’, funded by the German Science Foundation (DFG). We offer a fixed-term researcher position (67% E 13 TV-L) for three years.

Research area:

In the current demand for sustainable energy supplies, the development and optimization of energy storage systems, such as Li ion batteries, is of increasing relevance. Currently applied Li⁺ conducting electrolytes, however, suffer from various shortcomings, such as flammability. The development of novel electrolyte concepts requires a molecular understanding of ion transport processes. Our activities in this field consist of multinuclear NMR (¹H, ⁷Li, ¹⁹F) studies of electrolytes, which involves the established method of ion diffusion measurements (PFG-NMR), while our group specifically developed electrophoretic NMR to measure the drift velocity of specific ion species in an electric field. The results provide a detailed picture of the transport of cations, anions and solvent, including their mutual correlations, yielding a basis for further material optimization.

Project:

Highly concentrated liquid electrolytes exhibit strong directional correlations in the movement of cations and anions, which influence both charge and mass transport. A theoretical description of the transport properties can be done in the framework of the Onsager formalism. In this project an experimental quantification of ion-ion correlation coefficients is performed by combining the methods of two research groups: Electrochemical data of the Roling group (U Marburg) are joined with NMR-based transport parameters of the Schönhoff group to obtain very precise values for the Onsager transport coefficients, yielding exact information about charge and mass transport properties. This approach is applied to three Li+- conducting liquid electrolyte systems: (i) Highly concentrated electrolytes based on organic carbonates; (ii) Sulfolane-based highly concentrated electrolytes; (iii) Localized high concentration electrolytes. Guidelines are to be drawn up on how the interactions in highly concentrated electrolytes can be balanced in such a way that the best possible charge and mass transport properties are achieved. Your task will be to perform multinuclear NMR transport experiments on the electrolytes and collaborate with the Marburg team to evaluate the data in the overarching theoretical framework.

Your tasks:

• Performing ion transport experiments by NMR pulsed field gradient methods
• Sample handling and further optimization of sample environment
• Data curation, fitting and modelling within the theory of ion correlations
• Collaboration and joint data treatment within the team
• Working in the project is expected to serve further academic qualification (PhD)

Our requirements:

Required:

• MSc degree in Physical Chemistry, Physics, or general Chemistry with a strong focus on Physical Chemistry
• Dedication to quantitative Physico-Chemical ways of thinking
• Experience in quantitative data treatment, such as fitting, calculations, error propagation
• Good command of written and spoken English
• Team-orientation, good communication skills, organisational skills, ability to work independently

Desirable:

• Previous training in NMR methods would be advantageous.
• Ideally you already have experience in development of experimental setups or basic programming skills.

Your benefits:

• A fully funded position for obtaining a PhD in Physical Chemistry
• Integration into a dynamic, international and interdisciplinary team
• Thorough training in modern NMR techniques
• Working in a dedicated project team between two universities
• Possibility to participate in national and international conferences
• Appreciation, commitment, openness and respect – values which are important to us.

The University of Münster strongly supports equal opportunity and diversity. We welcome all applicants regardless of sex, nationality, ethnic or social background, religion or worldview, disability, age, sexual orientation or gender identity. We are committed to creating family-friendly working conditions. Part-time options are generally available.

We actively encourage applications by women. Women with equivalent qualifications and academic achievements will be preferentially considered unless these are outweighed by reasons which necessitate the selection of another candidate

Further information about the research group at https://www.uni-muenster.de/Chemie.pc/en/forschung/schoenhoff/index.html

For questions, please do not hesitate to contact Prof. Dr. Monika Schönhoff (schoenho@uni-muenster.de).

Please send your application in a single pdf file, consisting of a motivation letter, curriculum vitae, description of your research experience and experimental lab skills, and transcripts of your BSc and MSc degrees to:

• University of Münster
• Institute of Physical Chemistry
• Prof. Dr. Monika Schönhoff
• schoenho@uni-muenster.de

before 4.10.2024. Other file formats cannot be accepted.