Catalysis for energy

Dr. Henrik Junge

The progressive usage of renewable energies such as wind and sunlight in Germany is accompanied by an increasing necessity to efficiently store these fluctuating energy sources. For these huge amounts of energy, between 4.5 and 40 TWh in 2020, the chemical (long term) storage as hydrogen, methane or liquid compounds would be suitable. In this respect, advancements in generation from suitable starting resources, its storage and back conversion to electrical energy are of particular interest. The activities of the group “Catalysis for Energy” focus on the development of catalysts for these technologies. See below for detailed descriptions of the topics:

The aim of our work is the development of appropriate and active catalysts that allow for the hydrogen generation from starting materials like methanol, bioethanol, glycerol, glucose and cellulose with high selectivities at ambient conditions. Here, especially the generation of carbon monoxide shall be avoided since this constitutes a poison for fuel cell catalysts. In addition to hydrogen, other valuable products like acetic acid, its ethyl ester, propandiol acetone and lactic acid are accessible.

Ref.:

  •  M. Nielsen, E. Alberico, W. Baumann, H.-J. Drexler, H. Junge, S. Gladiali, M. Beller, Nature 2013; 495, 85-90; Low-temperature aqueous-phase methanol dehydrogenation to hydrogen and carbon dioxide. 
  • P. Sponholz, D. Mellmann, C. Cordes, P. G. Alsabeh, B. Li,Y. Li, M. Nielsen, H. Junge, P. Dixneuf, M. Beller, ChemSusChem, 2014, 7, 2419-2422; Efficient and Selective Hydrogen Generation from Bioethanol using Ruthenium Pincer-type Complexes.
  • Y. Li, P. Sponholz, M. Nielsen, H. Junge, M. Beller, ChemSusChem, 2015, 8, 804-808; Iridium-catalyzed Hydrogen Production from Monosaccharides, Disaccharide, Cellulose and Lignocellulose.

The direct photocatalytic generation of hydrogen, carbon monoxide formic acid as well as further products by application of sufficiently available sun is the goal of various projects in the group. A special focus lies on the development of noble metal free and abundant catalyst systems.

Ref.:

  • F. Gärtner, B. Sundararaju, A.-E. Surkus, A. Boddien, B. Loges, H. Junge, P. H. Dixneuf, M. Beller, Angew. Chem. 2009, 121, 10147-10150, Angew. Chem. Int. Ed. 2009, 48, 9962-9965; Light driven Hydrogen Generation: Efficient Iron-based Water Reduction Catalysts.
  • S.-P. Luo, E. Mejía, A. Friedrich, A. Pazidis, H. Junge, A.-E. Surkus, R. Jackstell, S. Denurra, S. Gladiali, S. Lochbrunner, M. Beller, Angew. Chem. 2013, 125, 437-441, Angew. Chem. Int. Ed. 2013, 52, 419 –423; Photocatalytic Water Reduction with Copper-based Photosensitizers: A Noble-Metal-Free System.
  • A. Rosas, H. Junge, M. Beller, ChemCatChem 2015, 7, 3316-3321; Photochemical reduction of carbon dioxide to formic acid using Ru(II)-based catalysts and visible light.
Fig. CO2-neutral hydrogen storage cycle

The storage of hydrogen is essential to establishing a hydrogen-based society. Methods including the application of carbon dioxide possess a huge potential. Based on the catalytic processes of formation and decomposition of formic acid, a CO2-neutral hydrogen generation cycle will be possible. For example such a cycle based on generation and decomposition of formic acid has been achieved in our group. An analogous cycle can be envisioned in the case of methanol. For both, MeOH and formic acid, the comparably high volumetric energy density constitutes a significant advantage.

Fig. Device for continious hydrogen Generation (up to 47 L H2/h) from formic acid developed at LIKAT

Ref.:

  • A. Boddien, D. Mellmann, F. Gärtner, R.Jackstell, H. Junge, P. J. Dyson, G. Laurenczy, R.Ludwig, M. Beller, Science, 2011, 333, 1733-1736; Efficient Dehydrogenation of Formic Acid using an Iron Catalyst.
  • A. Boddien, C. Federsel, P. Sponholz, D. Mellmann, R. Jackstell, H. Junge, G. Laurenczy, M. Beller, Energy & Environmental Science 2012, 5, 8907-8911; Towards the Development of a Hydrogen Battery.
  • P. Sponholz, D. Mellmann, H. Junge, M. Beller, ChemSusChem 2013, 6, 1172-1176; Towards a practical Setup for hydrogen production from formic acid.

Also in this part, the focus lies on the development of abundant and non-noble metal-containing catalyst materials for the replacement of platinum and iridium catalysts in fuel cells and electrolysers. Therefore, concepts from homogeneous catalysis are applied in heterogeneous catalysis, and thus combined with the advantages of the latter.

Core-shell nano particles on carbon
fuel cell equipped with a LIKAT-catalyst

Ref.:

  • R. V. Jagadeesh, A.-E. Surkus, H. Junge, M.-M. Pohl, J. Radnik, J. Rabeah, H. Huan, V. Schünemann, A. Brückner, M. Beller, Science, 2013, 342, 1073-1076; Nanoscale Fe2O3-based Catalysts for Selective Hydrogenation of Nitroarenes to Anilines.
  • R. V. Jagadeesh, T. Stemmler, A.-E. Surkus, M. Bauer, M.-M. Pohl, J. Radnik, K. Junge, H. Junge, K. Junge, A. Brückner, M. Beller, Nat. Prot. 2015, 10, 916–926; Cobalt-based nanocatalysts for green oxidation and hydrogenation processes.

Various projects have been performed or are currently in progress dealing with the above mentioned topics. They are funded either by the Europaen Union, the German Research Foundation, the Federal Ministry of Education and Research (e.g. “Light2Hydrogen”, within the frame of “Spitzenforschung und Innovation in den neuen Ländern”), the AIF or the Ministry for Economy of Mecklenburg- Western Pommerania. Our group collaborates with well known German as well as international scientists and industrial partners. In addition, we are well equipped with powerful instrumentation and suitable analytical Tools.