The reduction of greenhouse gas emissions and the emerging political focus on hydrogen as a clean energy carrier is driving research into sustainable hydrogen production and its use. Efficiency, lifetime and sustainability of the entire process chain play an important role. The Fuel Cells and Hydrogen Working Group at TU Graz is engaged in basic and industry-related research to address the above challenges.
Generation of high-purity hydrogen
One focus of the Working Group of Prof. Hacker is the development of a new process for the production of high-purity hydrogen, the so-called Reformer Steam Iron Process (RESC). In this process, a contact mass based on iron (oxide) acts as oxygen carrier and produces pure hydrogen by its reoxidation with steam. The high process temperatures in the range of 600-1000°C and the constant chemical transformation pose major challenges, as these lead to permanent structural changes and phase transformations of the metal oxides. Optimisation of suitable thermally and chemically stable metal oxides are achieved by adding refractory inerts such as aluminium, silicon or zirconium oxide and improving the preparation route for oxygen carriers increases the mechanical integrity and oxygen exchange capacity of the metal oxides. The working group is currently involved in the Bio-Loop project in cooperation with BEST Research and Technical University Wien, among others, to develop and improve such oxygen carriers also for future biomass-oriented applications.
R&D of hydrogen fuel cells
To enable a sustainable global economic system, the development of clean and silent propulsion systems for transportation applications is imperative. For use as power supply in electric vehicles (FCEVs), polymer electrolyte fuel cells (PEFCs) are currently seen as the viable option. The combination of long ranges and fast charging makes this technology particularly attractive.
The membrane electrode assembly (MEA) forms the heart of a PEFC, but is also the main cost driver, for current fuel cell stacks in FCEVs, as relatively high amounts of the precious metal platinum are used in the electrode catalyst. To reduce precious metals, a new concept was recently successfully developed at CEET, focusing on selective coating of the carbon support material with polyaniline (PANI), a semiconducting polymer to increase catalyst lifetime.
In collaboration with international research partners and industry, the materials were synthesized and characterized in the MEA with specifically designed accelerated stress tests to determine their performance in long-term operation.
Sources for this article:
CEET – Official website
Prepared by: Prof. Viktor Hacker, DI Michaela Roschger, DI Sigrid Wolf, H2greenTECH project partners from Institute of Chemical Engineering and Enviromental Technology (CEET) of TU Graz.