Development of thin-film catalyst with low noble metal content for unitized regenerative fuel cells (TAČR)

Most developed countries are increasingly utilizing renewable energy (i.e. solar and wind). One of the obstacles that has to be overcome is the volatility of generated power that usually does not meet the immediate consumption characteristics. Possible solution is to convert overproduced electricity to hydrogen via proton exchange membrane water electrolyzers (PEMWE) and subsequently during windless days or during nights the stored hydrogen would be converted back to electricity by means of proton exchange membrane fuel cells (PEMFC) to compensate the deficit.

Submitted project aims to investigate the application potential of unique platinum-iridium reversible catalyst which is being developed in our research group. Simply put, the reversible catalyst enables to merge PEMWE and PEMFC technologies to single PEM unitized regenerative fuel cell (PEM-URFC). This would lead to significant reduction in price of above described “electricity-hydrogen-electricity” buffering system since the hardware is basically reduced to half. Moreover, the sophisticated preparation method (multitarget segmented magnetron sputtering) leads to thin-film distribution of noble metals which additionally contributes to the price reduction. Currently the noble metal catalysts (Pt and Ir) represent major fraction of PEMFC and PEMWE cost breakdown; our catalyst loading is 3x lower compared to PEMFC standard and 4-5x lower compared to PEMWE standard. Our catalyst shows high values of specific performance, however due to the complex character of testing we were unable to fully confirm its long-term stability. Obviously, this parameter is key from the application standpoint.

We intend to use the financial support of project Gama to set up dedicated testing station for accelerated aging experiments. We plan to identify potential degradation processes which might happen during the lifespan of reversible catalyst and if needed we will optimize the deposition process in order to prevent them.