Center for Renewable Hydrogen Cycling

All long term visions about the use of hydrogen as an energy carrier include electrolysis. Unfortunately the efficiency of water splitting by electrolysis is rather low, and there is a large potential for improvement. This project focuses on the development of new anode materials and other materials for acidic electrolysis or for photocatalysis for hydrogen production. Such new materials are necessary, if these technologies are to be used on a larger scale for averaging out electricity production from sustainable energy resources in the future.

One of the biggest challenges for making efficient photocatalysts is to find materials that possess low overpotentials for the oxygen evolution process. Similarly, low overpotentials are necessary for electrolysis in acidic environments, as the polymeric electrolyte membrane water (PEM) electrolysis. Theoretical investigations have now matured to a degree where one can pin point materials that are reactive enough that they can dissociate water while not binding site-blocking intermediates such as oxygen and hydroxyl groups too strongly.

By assembling research groups encompassing theory, biomimitics, materials synthesis and testing, as well as the industry we can develop new approaches for solving this crucial problem. Theory, in this case Density Functional Theory (DFT) calculation, will direct the investigations towards the type of materials that are the best candidates for the reactions of interest. The synthesis will cover a broad range of methods including biomimetic approaches. The resulting materials will be tested both electrochemically and photocatalytically in the university laboratories as well as in industrial laboratories.

The overall targets are to obtain higher efficiency and lower prise for the PEM electrolysers, and to explore the possibilities of hydrogen production in photo-catalytic cells as an alternative. For both types of cells the overpotential of oxygen formation is an important limitation of the efficiency, and this is related to catalyst materials used as already mentioned. Furthermore, catalyst materials contribute very significantly to the cost of the cells, and there is a demand for new, cheaper materials. For the electrolyser cells a considerable increase in efficiency can be obtained by increasing the working temperature, because of the decreased thermodynamic energy requirement, enhanced electrode kinetics, and the possible integration of the heat recovery. However, this increases the demands to all materials used with respect to corrosion stability and thermal stability.

To achieve these targets, it is thus critical to develop and improve the materials of which the water splitting cells are built.

The HyCycle Centre is financed by The Danish Council for Strategic Research, and its activities were started in year 2008.

The partners are five Danish university groups - from the Technical University of Denmark and University of Southern Denmark -,  as well as three industrial partners. These industrial partners are IRD Fuel Cells A/S, Tantalum Technologies A/S and Danish Power Systems ApS.