Research Statement

As a greenhouse gas, CO2 contributes to global warming significantly. Creating a carbon-neutral cycle via converting CO2 back to value added chemicals such as carbon monoxide, methane, methanol etc. contributes to the efforts in curbing the effects of global warming.

The Haber-Bosch process is the main industrial process for the artificial fixation of nitrogen. This process consumes 1-2% of the world’s energy supply and indirectly contributes to the 3-5% release of annual anthropogenic CO2. In recent years, researchers have been attempting to find a catalyst that is able to realize this process in ambient temperature and pressure.

To this end, our research focuses on design, development and implementation of catalytically active materials for addressing the abovementioned problem. We combine the two major fields of catalysis, namely photocatalyis and electrocatalysis to create a synergistic effect resulting in photoelectrocatalysis where the electrode materials are the sensitizers and the catalysts at the same time.

[Translate to English:] MOCHAs

© Hannah Rabl

 Metal Organic Chalcogenolate Assemblies (MOCHAs) are an emerging class of 1D and 2D organic-inorganic hybrid materials. Early stages of MOCHA research have focused on the synthesis and structural characterization of MOCHAs as well as their physicochemical properties. However, the low synthetic yield prevented them to be utilized in various applications. Recently, our group overcame this barrier by introducing a microwave-assisted synthesis method which increased the synthetic yield by x100. We utilize MOCHAs mainly in electrochemical CO2 conversion as efficient electrocatalysts.

Photocatalysis

© Jakob Blaschke

We utilize various Metal Organic Frameworks (MOFs) for the gas-phase photocatalytic CO2 reduction. MOFS are crystalline materials with a lot of surface area enabling more active sites for catalytic conversion. We use MOFs as photosensitizers and CO2 storage medium while we attach molecular/metal co-catalysts into the pores for photocatalytic CO2 conversion. Furthermore, we observe the reaction mechanism using operando Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS).

Hydrogen development

© Dorottya Varga

Hydrogen has been hailed by the EU as the future energy resource and EU aim produce to 10 million tonnes of green hydrogen by 2030. However, currently only 3.9% of the worldwide hydrogen production comes from water electrolysis. The rest produced using fossil fuels causing green-house gas emissions. Green hydrogen production methods for a sustainable future are needed. On the other hand, cleaning of wastewater that are contaminated with persistent pollutants also pose a challenge. We tackle this problem an innovative reactor concept in collaboration with AEE-INTEC and GREENoneTEC that simultaneously remove pollutants from wastewater and produce green hydrogen. The project is funded by Austrian Research Promotion Agency (FFG).

Electrocatalytic CO2-Reduction Graphic

© Dorottya Varga

Formic acid is a versatile chemical that can serve as a renewable energy carrier, a platform chemical for various industries, and a means for CO2 capture and utilization. Electrochemical reduction of CO2 to formic acid is a promising technique because it offers high selectivity and tunability over the reaction. Formic acid is a promising Liquid Organic Hydrogen Carrier (LOHC), as it carries a relatively high amount of (4.3 mass%) of hydrogen while being an easily handleable chemical that is miscible with water and not chemically aggressive to many potential materials that can be used for fuel storage. Apart from that, formic acid is naturally occurring in many plants and, best known, ants.

In our laboratory, we convert CO2 to formate using p-block metals in combination with metal oxides. We also investigate the photoelectrochemical conversion of formic acid back to CO2 and hydrogen.

Green Hydrogen

© Stefan Pfaffel