22
(II) Experimental Parameters
Choose the appropriate current range for the material being measured. Fc will give a signal in the tens
to hundreds of microamps, therefore the 200 μA range should be selected from the drop-down box
(Autorange can also be used).
The scan profile needs to be defined. In a cyclic voltammetry measurement Fc undergoes a reversible single
electron transfer between 0 and 0.2 V (versus Ag/AgNO
3
). We can therefore use the scan profile shown
in
Figure 9.13
, sweeping the voltage from -0.4 V to 0.6 V and back to -0.4 V. Set the “Start Potential” and
“Potential Vertex 2” fields to -0.4 V and the “Potential Vertex 1” field to 0.6 V.
The scan rate and number of cycles need to be set. The scan rate will affect the magnitude of the current
peaks in the scan, with faster scan rates resulting in greater measured currents. In this measurement we
will use a scan rate of 100 mV/s, so set the “Scan Rate” field to 100 mV/s. The number of cycles is how many
times the measurement will be performed, and typically is set to “1”. The full settings used are shown in
Figure 9.14.
Figure 9.13.
Potential scan profile for the ferrocene measurement.
Figure 9.14.
Measurement settings for ferrocene.
Summary of Contents for T2006A
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