Questions and problems about our reference electrodes

Yes, the replacement cells can be stored.

In general, you should activate the cells after about 2 years at the latest. If in doubt, just ask us.

There are no special requirements for storage.

Cause 1: poor contacting
Check the test leads on optical damages such as corrosion, cracks, and sessile plugs. Replace the test leads.
Check the electrode with an external reference electrode, e.g. a calomel or silver silver chloride electrode.

 

Cause 2: no or too little hydrogen production
Did you wait for the activation phase in water of 24 hours?
If not, wait 24 hours before you measure.
Is the duration of the cartridge / hydrogen cell exceeded?
If yes, please clean the hydrogen electrode and replace the old cartridge / cell with a new one.

 

Cause 3: slow ion exchange, e.g. when you switch from concentrated solutions to weak concentrated solutions
Wait the setting time, sometimes the balancing of concentrations lasts longer than expected.
If necessary, check the potential in another electrolyte such as 1 mol/l hydrochloric acid.

 

Cause 4: air/oxygen gets to the electrode
Avoid that gases such as air or oxygen reach the hydrogen electrode’s shaft. If this happens the hydrogen is displaced or reacts off. No hydrogen potential can be set.

Cause 1: hydrogen bubbles of the hydrogen electrode itself
Bubbles are continuously leaking out of the hydrogen electrode. Some bubbles are small, others are bigger. Usually, they do not disturb your measurements.
Is a big bubble forming at the bottom of the hydrogen electrode which sticks to the vessel wall? If possible, place the electrode further away from the vessel wall or hang the hydrogen electrode transversely into the measuring vessel.

 

Cause 2: induced gases
Change the position of your gas inlet.
Induced gas bubbles which are piped by close to the hydrogen electrode can disturb the measurements and lead to fluctuating potentials.

 

Cause 3: potentiostat or measuring device
Check your measuring device.
If you measure in low conductive electrolytes, potentiostats and measuring devices quickly reach their limits.

The hydrogen electrode is contaminated, and a mixed potential is set.
Check the runtime of the hydrogen supply and replace it if necessary.
Some deposits can be wiped off with a cloth.

For the Mini-HydroFlex you can carefully sand the bottom of the electrode with 1000 grit sandpaper.
More stubborn impurities dissolve in 1 mol/l nitric acid. The electrode must then be rinsed thoroughly in distilled water.
If that is not successful, the electrode is so badly contaminated that we suggest a new purchase.