Oxygen evolution reaction catalysts current density

Figure 4. Polarization curves of carbon corrosion and oxygen evolution reactions based on measured carbon corrosion kinetics for Pt/Vulcan and Pt/Graphitized-Vulcan and oxygen evolution kinetics for Pt/C catalysts. The upper horizontal dotted line denotes a current density equivalent to oxygen crossover through membrane from cathode to anode.

In the case of anode starvation, an anodic side reaction is required. Due to the low exchange current density of the oxygen redox reactions, even in the presence of a noble metal catalyst other side reactions (e.g. Pt dissolution or carbon corrosion) will take place in parallel to oxygen evolution. The potential of the anode will therefore rise significantly. 

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