The focus of my PhD research project is the investigation of electrochemical oxygen catalysis on single-atom-center (SAC) motifs on MXenes. I employ density functional theory (DFT) calculations combined with a descriptor-based analysis to analyze the activity and selectivity of different MXenes for the oxygen reduction (ORR) and oxygen evolution reaction (OER). Free-energy diagrams along the reaction coordinate are utilized to gain fundamental insights into the limiting processes of and factors governing selectivity for the ORR and OER.