Fine-tuning the activity of oxygen evolution catalysts: The effect of oxidation pre-treatment on size-selected Ru nanoparticles

- Mass-selected Ru nanoparticles have been investigated for the oxygen evolution reaction in acid.
- The effect of thermal oxidation and oxygen plasma treatment has been studied.
- The activity and stability could be tuned using different oxidation treatments.
- Thermally oxidized nanoparticles exhibited the highest stability but lowest activity.
- Plasma treated nanoparticles showed intermediate performance.