How do you maintain reference electrodes?

Proper reference electrode care must be taken to ensure continued accurate measurements. The tip of the reference electrode is porous glass frit or electro porous KT glass (opaque white). The frit allows ionic transport into the electrode. In order to operate properly the frit must always be kept wet with electrolyte.

How do you test a reference electrode?

To test the potential difference between a reference electrode and the master reference electrode with a multimeter, simply connect one lead of the multimeter to the active laboratory reference electrode under study and the other lead to the master reference electrode (see Figure 4).

What are the major requirements of a reference electrode?

A secondary reference electrode must fulfill the following criteria: (i) it should be chemically and electrochemically reversible, i. e. its potential is governed by the Nernst equation and does not change in time; (ii) the potential must remain almost constant when a small current passes through the electrode and …

How do you calibrate a reference electrode?

Calibration:

1. Take a multi-meter, a Pt electrode, and the Ag/AgCl reference electrode.
2. Hydrogen gas (10-20% in Ar or N2)
3. Make 0.5 M H2SO4 (1 M H+)
4. Connect the reference and counter electrode with two-probe multi-meter.
5. Immerse the electrodes in the H2SO4 electrolyte and bubble H2 near Pt electrode.
6. Measure the potential.

What should the electrochemical potential of a reference electrode be?

You can do that with a voltmeter, or with your Gamry Potentiostat by running and open circuit potential. If the potential difference is less than 2-3 mV, it’s OK. If it’s higher than 5 mV, it needs to be refreshed or discarded. Everyone agrees that an ideal reference electrode has a stable, well-defined electrochemical potential.

When does a reference electrode need to be replaced?

A porous glass frit should be replaced if the impedance of the reference electrode is out of specification (see above), or if it has been allowed to dry out, has been cracked or chipped, or if it has become discolored. A frit cannot be reused.

How long do reference electrodes last in a detector?

By rotating the three reference electrodes provided with your detector on a continuous basis, you can maximize their lifetimes. Depending on the mobile phase conditions and detector use, the reference electrodes can last from 3-6 months. When you replace reference electrodes, replace all three of them at the same time.

How to test the viability of a reference electrode?

If you are concerned about the viability of a particular Ag/AgCl reference electrode, you can test it using a simple voltmeter, additional reference electrodes of the same type (or a calomel reference electrode), and a small beaker of 3 M NaCl.