Green electrochemical synthesis and characterization of MXenes for sustainable energy

To minimize the consequences of climate change, stopping greenhouse gas emissions and thus decarbonization of the energy supply chain is crucial. A highly promising solution is the utilization of fuel cells, which require hydrogen for energy generation. The supply of hydrogen by green technologies like water splitting is not economically feasible yet.

To resolve this issue, cheap and efficient catalysts to drive this reaction are required.

In the recent years, 2D materials moved in the focus of research as some of them show excellent catalytic activity to support the electrochemical splitting of water to obtain hydrogen.Among the vast field of 2D materials, MXenes are potential earth-abundant candidates with high stability and a broad range of potential applications, including the catalysis of water splitting.

To date, 30 different MXenes have been synthesized, while more than 100 of them are predicted. However, established protocols use hazardous chemicals for the synthesis.

Among the different methods, electrochemical etching of MAX phases to MXenes has the highest potential for an environmental approach.

Thus, the main effort of this project is to develop electrochemistry-based synthesis routes for MXenes using environmentally friendly chemicals.

The developed techniques will be evaluated in terms of yield and the structural and electrochemical characteristics of MXenes will be correlated.The etching process will be further optimized using scanning electrochemical microscopy.

The technique enables the analysis of the localized electrochemical activity and the electrocatalytic activity towards the hydrogen evolution reaction.

This will provide a deeper knowledge about the etching process in two regards: The minimum time required to achieve full conversion of MAX phase to MXene on an electrode surface can be determined, and local differences in catalytic activity can be spotted and correlated with structural and chemical deviations.