reference electrode is a kind of commonly used reference electrodes.
AgCl + e = Ag + Cl- E0 = 0.199V vs. NHE 25 C
D.J.Ives and G.J.Janz, "Reference Electrodes," Academic
Press, New York, 1961
There is an example of adding a Luggin Capillary to reference
electrode. The purpose is closing the reference electrode to
the surface of the working electrode for reducing the IR drop.
Regarding Luggin Capillary, the figure below is a diagram of
the reference electrode was drawn to classical textbooks. There
is a salt bridge between the working electrode and the reference
electrode. But in this case, the distance from the working electrode
and the reference electrode is long that easily courses potential
instability. And the air is also easy to enter long salt bridge.
In particular, the high frequency impedance measurement will
Saturated Silver/Silver Chloride Reference Electrode is
integral to the reference electrode and luggin capillary, which
was to simplify the structure shown above.
Electrode in a double structure, saturated KCl solution put
inside, which is it is easy to refill or change the saturated
KCl solution. The liquid junction of the inner tube is porous
ceramics. The electrolyte solution is sucked into the outer
tube with a rubber dropper.