2-propanol fuel cells
Instead of storing energy directly in the form of hydrogen, one can use systems based on liquid organic hydrogen carriers (LOHCs), i.e. organic compounds which can be catalytically (de-)hydrogenated. This is the focus of the Research Department Chemical Hydrogen Storage and of the large HI ERN project Emission-free and highly emission-reduced rail traffic on non-electrified lines.
One of the approaches to utilize the hydrogen stored in an LOHC is to hydrogenate a ketone to a secondary alcohol via catalytic transfer hydrogenation, and then use the alcohol as a fuel in a fuel cell to deliver electricity. To enable a fully closed cycle, the anode fuel cell reaction must be selective to the ketone, without forming any by-products which cannot be easily hydrogenated again by the LOHC.
We work on the oxidation of 2-propanol to acetone in acidic and alkaline solutions. Our goal is to find materials that can catalyze the reaction with:
- high activity as close to the equilibrium potential as possible
- selectivity to acetone without the formation of CO2 to ensure the reversibility of the process
- tolerance to poisoning from adsorbates which can deteriorate performance with time
We use classical electrochemical setups to understand the fundamental electrocatalytic trends and to guide the rational design of new catalysts. We additionally use EC-RTMS to characterize the products of the reaction in real-time and to screen material libraries in order to find more efficient electrocatalysts.
The work is funded by The Bavarian Ministry of Economic Affairs, Regional Development and Energy, under the project Emission-free and highly emission-reduced rail traffic on non-electrified lines. We naturally collaborate with a large number of scientists within the HI ERN who are involved in the project.
- G. Sievi et al.; Energy Environ. Sci. 2019, 12, 2305-2314