Using a well-defined redox couple

A well-defined redox couple can be used to calibrate an RE or as an internal standard in electrochemical experiments. The reference redox couple must be stable for the duration of the measurement, and must exhibit a repeatable potential in the system used. A good reference redox couple (63) for nonaqueous, and some carefully controlled aqueous systems, is the ferrocene/ferrocenium (FcIFc ) couple at 0.5-10.0 mM concentration. Standard reduction potentials, E°, for various solvents (64) are listed in Table 4.10. Other couples can be found in References (64-66). 

Do not connect the CE, turn the cell on, or attempt to control the current or potential 

Note Other reference redox systems include Rb/Rb and Fefbpylj / Fe(bpy)3 + (where bpy 2,2 -bipyridine). 

1 Verifying the potential of an RE with a well-defined redox couple 

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Figure 4.21 Calibration of an RE using a well-defined redox couple (67).

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