Content presentation of the 4th Boysen-TUD-RTG - Cluster G

Electrocatalysts for a competitive hydrogen economy

Disciplines involved

Inorganic chemistry, laboratory and process technology, electrochemistry, didactics/educational sciences

Motivation and goals of Cluster G

The realization that hydrogen, as a versatile energy carrier, has a key role to play in achieving the climate targets set, is reflected in strategic concepts of leading industrial nations, such as the national hydrogen strategy of the German federal government or in strategy papers of the US Department of Energy (DOE) on the further development of fuel cell technologies for mobile and stationary applications. The main criteria for the usability of fuel cells are maximum efficiency, specific power, start-up times, durability, and costs. In particular, the insufficient stability and the high costs of production are still preventing the widespread market introduction of the technology. The catalyst materials, which are necessary to promote the reactions that take place at the electrodes, play a significant role in the high costs. In particular, the oxygen reduction at the cathode, which proceeds only very slowly, must be accelerated by high-efficiency noble metal catalysts. Although these catalysts demonstrate high efficiency, the high price of the platinum-containing starting compounds thus contributes to almost half of the production costs of such cells. In order to fully exploit the potential of hydrogen as a green energy carrier in the near future, societal acceptance for new technologies must be given. A Europe-wide study conducted in 2017 found that, while there is a positive perception of this in parts of the population, there has so far been little willingness to buy this new technology, not least because of the high purchase price and doubts about its technological maturity. It is clear from these surveys that further technological development must go hand in hand with strategies for educating the population and strengthening social acceptance.

In Cluster G, highly efficient noble metal-free electrocatalysts are to be developed, which will form the basis for the future competitiveness of fuel cell technology, in particular for use in AEM (Anion Exchange Membrane) cells. A particular focus of the scientific work will be to gain a deeper understanding of the underlying mechanisms of oxygen reduction and evolution on heteroatom-doped and molecularly functionalized carbons. Another important aspect is the consideration of the topic in the field of tension between society and the achievement of self-set climate goals. The concepts for strengthening social acceptance start in teacher and student education. New research-oriented modules on the topic of "fuel cell technology" are being developed, which are to be designed as prototypical educational modules for sustainable development and made permanent in teacher training.

Scientific added value targeted in the cluster

The project aims to develop a deeper understanding of the processes occurring at the electrodes during electrocatalyzed oxygen reduction in fuel cells. By elucidating the relationships between the structure of refined carbon materials and their catalytic activity, targeted material design for highly effective electrocatalysts will be made possible. Cluster G will also contribute to strengthening the social acceptance of fuel cell technology, in particular, and the understanding of research in the context of sustainable developments, in general, with a concept for prototypical research-oriented teaching modules. The modules have a model character and the developed methodological competence can be extended to other teaching systems. In this project, the multiplier function is to be emphasized.

The subprojects in detail

Cluster G is composed of three subprojects (SP G1 to SP G3).

SP G1 - Experimental studies on doping of carbon materials and influence of functional groups on electrocatalytic activity in cathodic oxygen reduction aims at the systematic investigation of heteroatom-doped carbon materials for use as electrocatalysts. The focus is primarily on a deeper understanding of the relationships between the structure of the functionalized carbon materials (specific surfaces, pore radius distribution, type, amount and location of functional groups introduced by doping) and the resulting electrocatalytic activity in oxygen reduction. The project benefits from the joint expertise in inorganic materials chemistry and physical electrochemistry (SP G2), as well as operando spectroscopy, in order to arrive at a targeted material design of optimized catalyst materials through structure elucidation also in situ. The technical supervision is provided by the Chair of Inorganic Chemistry I (first supervisor Prof. Stefan Kaskel, second supervisor Dr. Julia Grothe) of the Faculty of Chemistry and Food Chemistry of the TU Dresden.

Within the framework of SP G2 - Functionalized Carbon Materials and Operando Analysis for Molecular Understanding of Electrocatalytic Activation of Oxygen and Hydrogen, the cathodic reactions of oxygen reduction and hydrogen evolution will be studied in particular. Both reactions require an efficient transport of protons to the catalytic center, which will be systematically investigated on heteroatom-doped and molecularly functionalized carbon materials using spectroelectrochemical techniques. A special focus is on investigations in dependence of the pore size. The project benefits from the expertise in inorganic materials chemistry (SP G1), which provides porous carbon electrodes. The knowledge gained here is to be didactically processed in SP G3 and incorporated into teacher and student training in the form of teaching materials. The Chair of Electrochemistry of the Faculty of Chemistry and Food Chemistry of the TU Dresden (Prof. Inez Weidinger) is responsible for the technical supervision.

SP G3 - Education for sustainable development and understanding of the processuality of scientific and technical research through research-oriented teaching-learning concepts and science communication provides an excellent example of processes of sustainable development. Therefore, it serves as a reference point for the development of prototypical research-oriented teaching modules for the subject-specific teacher training as well as for student internships in the teaching-learning laboratory of the TU Dresden. The modules have model character in the sense of education for sustainable development, they serve the teacher training and further education in this field and can thus be transferred to the cluster-connected reference energy park Autarker Energiepark. In addition, a concept for science communication accompanying the project will be implemented. The professional supervision is carried out by the Chair of Construction, Wood and Paint Technology and Interieur Design / Vocational Didactics of the Faculty of Education at the TU Dresden (Prof. Manuela Niethammer).