Heterogeneous electrocatalysts

Dr. Annette-Enrica Surkus

In view of the use of regenerative energy sources and the storage of surplus electricity, electrochemical technologies are increasingly becoming the focus of research, industry, and politics. In this context, we are developing active heterogeneous electrocatalysts, particularly composites with reduced content of precious metals such as iridium or platinum (or, if possible, noble metal-free catalysts that contain only readily available components). Our work was originally funded by the AiF and the Ministry of Economics of the state of Mecklenburg Vorpommern with the participation of regional SMEs, subsequently also in cooperation with industry (Evonik Industries, Siemens Energy AG) financed by the BMBF (e.g. Kopernikus, H2Giga) or with international participation (CADIAC). Our work includes the development of electrocatalytically active materials for oxygen reduction (ORR) in fuel cells and for hydrogen generation (HER) and oxygen generation (OER) in alkaline and acidic water electrolysis. For example, the SusHy project succeeded in developing a highly active oxidation catalyst for alkaline water electrolysis [1,2]. In addition, we are developing and testing "solid oxide" composites as cathode materials for "Solid State Ammonia Synthesis" (SSAS), in which nitrogen is electrochemically reduced to ammonia between 400 and 600°C (WIR!-Campfire). As an energy-relevant topic, we are also interested in electrochemical CO2 reduction (eCO2RR) using heterogeneous electrocatalysts. The subject of our current work in the field is the development of materials that preferentially reduce CO2 to C2+ products despite the presence of water.

The developed materials, such as the chitosan-derived gels shown in the figure below (from left to right loaded with Mn, Fe, Cu, Ni, Co), are comprehensively characterized in cooperation with the LIKAT-department Analytical Services, for instance by SEM and TEM (see figure, bottom left and right).





[1] M. Polyakov, A.-E. Surkus, A. Maljusch, S. Hoch, A. Martin, ChemElectroChem 2017, 4, 2109-2116; Impact of the Co : Cu Ratio in CoCu-Containing Oxidic Solids on their Activity for the Water-Splitting Reaction.

[2] A. Maljusch, A. Martin, M. Polyakov, A.-E. Surkus, S. Hoch, M. Blug, W. Deis, Verfahren zur Herstellung eines in der Wasseroxidation einsetzbaren Elektrokatalysators, 2015E00266, EP2017/074926, WO2018/065339 A1.