Vernier Go Direct Manual page 2

Using the Product with Instrumental Analysis
Preparing your Instrument for Data Collection
1. Insert a screen-printed electrode (SPE) into the SPE connector on the Cyclic
Voltammetry System (see Figure 1). Avoid touching the black electrode part
of the SPE.
2. Fill the scintillation vial about halfway full (~10 mL) with your sample. Insert
the scintillation vial into the clip on the stand. Carefully guide the Cyclic
Voltammetry System with the SPE attached downward into the vial and snap
the instrument into place, as shown in Figure 2.
Selecting Experiment Type
The three options for Experiment Types are
Cyclic Voltammetry
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Bulk Electrolysis
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Open Circuit Potentiometry
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1. Connect the sensor following the steps in the Getting Started section of this
user manual. The Voltammetry Settings menu should be open automatically.
2. Select the desired experiment type. Cyclic Voltammetry is selected by default.
The default parameters are appropriate for measuring a cyclic voltammogram
for common samples in a buffer solution. You may want to adjust these
settings according to the student instructions in the Electrochemistry
Experiments with the Go Direct Cyclic Voltammetry System e-book.
Figure 1
Figure 2
3. Click or tap Collect to begin data collection. The run will stop automatically or
you can choose to end it early.
4. Name your sample appropriately. To do this, click or tap on the y-axis label.
Click or tap on Data Set Options next to the data set you wish to rename. Click
or tap Rename Data Set. Enter a name for the sample and click or tap Rename.
5. Analyze the voltammogram by selecting the desired peak. Click or tap Graph
Tools, , and choose View Statistics. You may also wish to analyze your
data using the peak integral function also located under the Graph Tools menu.
6. When you are ready to change your sample, carefully remove the Cyclic
Voltammetry System from the stand by pulling back on the top tab (Figure 3).
7. With the SPE still inserted in the Cyclic Voltammetry System, rinse the SPE
with buffer solution, and dry it by gently blotting the electrode surface with a
piece of paper towel. Important: Do not invert the Cyclic Voltammetry
System with a damp SPE attached. You want to avoid getting liquid inside the
SPE connector.
8. Repeat Steps 2–7 for as many samples as you test. To change the parameters
between runs, click or tap Voltammetry Settings,
9. When you are finished with you experiment, discard the solution and SPE as
instructed. Click or tap on the File Menu to Save or Export your data.
Changing the Settings in Instrumental Analysis
Click or tap the slider, , to show the Voltammetry Settings dialog. You will set
the Experiment type you wish to perform here. There are multiple parameters
listed in the dialog box that will vary based on the experiment you have selected.
Cyclic Voltammetry
In this experiment type, the electrode potential ramps linearly with time in a preset
waveform, often through the electroactive species' standard potential, which
allows for the investigation of the resulting electrochemical species generated at
the electrode surface. The rate of voltage changes over time during each of the
segments in the waveform, known as the experiment's sweep rate. The potential is
measured between the working electrode and the reference electrode on the SPE,
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Figure 3
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