Dear all,
we bought a kit for DSSC preparation in order to test some natural dye. Anyway, the kits arrived without any "instruction", and since we are not experts we are struggling to understand if we are doing something wrong.
This is the protocol that we are using:
the dye is dissolved in EtOH. We transfer drops of this solution on the titania electrode, waiting for the solvent to evaporate and repeating the operation several times. Eventually, the electrode is washed with EtOH in order to remove the excess, and left to dry on an heating plate at 75 C. At this point the TiO2 has a quite strong color, and enough dye should be present. After, the gasklet mask is applied to the electrode(it's a sort of frame that is going to surrounds the TiO2, not clear if it's necessary to keep the electrolyte solution in position or to better keep the electrodes in contact). Anyway, some drop of electrolyte solution of Iodolyte AN-50 is put on the TiO2, and the platinum electrode placed on the top. We use also some clamp to keep the electrodes together.
Can you spot some mistake in the preparation?
Note that the platinum electrode is pierced, and that hole goes in correspondence of the TiO2. We also saw that the resistance measured increases over time, and that it's reduced when we add a new drop of electrolyte solution between the electrodes. Is it possible that the problem is the electrolyte itself?
In the kit are also present caps made of the same polymeric film of the frame,but with the rectangular shape that adapts perfectly to the TiO2. We don't put it. since we didn't find any article/example where it was used. Also Ruthenizer and Chenodeoxycholic acid are present, to use as reference.
Please, feel free to comment or give your advice.
Hi. I think the problem is that your electrolyte solvent is volatile, which gets dry early
Hi Pierluigi,
Your problem is that the solvent in your electrolyte will evaporate the way you described that you fabricate your cells. You will need to do closed DSCs to be able to measure the cells properly. From what you describe your test cell kit has all the components you need in order to to that:
Usually you dip the whole TiO2 electrode into the dye solution and leave it for several hours up to overnight in that dying solution. Then you take it out, rinse it with the solvent used and dry in a stream of N2.
Now for the counter electrode you will need to put the gasket around the TiO2, then put the counter electrode on top and seal it by applying heat (for example with a soldering iron) while you're pressing the electrodes together. Note that you should try not to overheat the cell as this might destroy your dye. Also the hole you describe in your question needs to be within the gasket as you will fill in the electrolyte through that hole.
Then you fill in your electrolyte through the predrilled hole, using for example a micropipette tip. Usually people do vacuum backfilling where you apply a vacuum first and then push the electrolyte in using positive N2 pressure. There are also special syringes you can buy from solaronix for example if you don't have a setup in place for vacuum backfilling.
Make sure you get all air out. Once filled, seal the hole with a cap and apply silver paste onto the ends of your electrodes where you connect them to your keithley for a better contact. Mask your cells before measuring to have a defined area you irradiate each cell and you should be good to go.
Maybe check out solaronix or dyesol if they have a manual in more detail.
The fabrication needs some practice to get reproducible results. Ideally you have someone to quickly show you how it's done.
Cheers,
Sebastian
Dear all, thank you for you kind answers. I really think that you have right Javad Marghzari.
I will try straight away using the setup that Sebastian Fürer suggested. I was already considering the evaporation of the electrolyte solution as possible explication, especially because I have the hole uncovered without cap. I didn't cover it since we have other cells, prepared around two years ago from another professor with the same dye, and these are still working (he used the same preparation of mine, also in this case the hole is uncovered).
I will use also the black mask that solaronix provided, to have the definite area. Still, I have some sealing in the kit, of the same material of the gasklet but of square shape compatible to the TiO2. Do someone know that these are used for?
Thank you Artur Braun for your observation, indeed I should check also this aspect.
I am just disappointed that the solaronix kit arrived with any instruction. I know that it's supposed to be used from experts, but it doesn't help who, such our team, never worked with these.
It is strange that such a basic instruction manual is missing from the kit. You must write to them and ask for the manual to be saved from any future mishaps.
Estimado, te puede ayudar
http://dspace.utpl.edu.ec/handle/123456789/10724?mode=full
Natalí Solano thank you for the document. Fortunately I am italian, I can understand :) It will be extremely useful
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