I am performing OER in alkaline medium with an SCE reference electrode. But there is heavy bubbling on the frit of the reference. What could be the reasons for this? And can I trust my results? The SCE is new and I had calibrated it , just before the OER activity check. Please find attched a pic of the same.
Probably, you have a solution oversaturated by O2/H2 gases. Glass frits are very good to start formation of small bubbles. You need to stir your solution to remove bubbles. SCE is not recommended for basic solutions,
As Prof Crabtree mentioned that from the attached photo it seems that your solution is oversaturated with gases, either due to purging your solution with nitrogen before the experiment or due to the generated gases (O2 and H2) due to water splitting. The later case can be maximized in case of long term experiments not CV or LSV, particularly since you are using large surface area electrode. So, if you are doing Chronoamperometry for long time, this is quite normal , and you don't need to worry about the results. To trust these results you may check its reproducibility. However, these intense bubbles will negatively impact your results since it can block some surface area of your working electrode. Finally, you may use Hg/HgO as a reference electrode under strongly basic conditions, if available.
Agree with Dr Geletii.
As a side note, if you are running the electrolysis at a constant potential check if your equipment allows you to measure the working electrode potential vs time. Bubbles formation on the frit of the reference electrode can lead to intermittent disruption of the electrolytic contact between the reference electrode body and the bulk solution, thus causing the WE potential to "jump" uncontrollably between undesired values. This can in fact compromise the results of your experiment.
Dear Darren Sebastian Christi ,
find a way[1] to avoid/reduce (blast) overpressure, due to outgassing[2], in your tightly closed cell.
1. About possible ways for outgassing: a)untighten the jar lid from your firmly(?) closed cell, or b)open a small hole in the cover, c)add an outgassing valve on the cover, ... etc.
2. during your OER studies.
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