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Article Single Ru Atoms Stabilized by Hybrid Amorphous/Crystalline F...
They said that: (( With the decrease of amorphous layer thickness, the overpotential increased continuously to 205 mV for the Ru SAs/AC-FeCoNi and 238 mV for the Ru SAs/C-FeCoNi )) meanwhile they report the 205mv as the lowest overpotential observed.