I am electrodepositing MnO2 using 0.01 M Mn-acetate (MnCH3COO) solution on glassy carbon substrate at 60 degress. The electrodeposited film does not have good adhesion and it usually peels off after drying at 100 degress.
Hi Ellie,
Can you please spell out the details like: what is your purpose of depositing EMD, what current density and temperature you are using. Whether the bath is static one?
Thanks
Hello Mr. Tripathy, the purpose of MnO2 deposition is for supercapacitor application. MnO2 has good charge storage properties. The electrolyte is Mn-acetate and I am stirring the solution at 250 rpm. The current density is 5 mA/cm2 and temperature is at 60 C
There are several ways to improve the adhesion quality of your deposit:1) polishing or sputtering/bombarding the substrate, 2) depositing an adhesion layer (one ML using UPD or electroless deposition tech or a few nm thick metallic layer using CVD/PVD/ Magnetic sputtering...etc tech), 3) acquiring a polarization curve using RDE (rotating disc electrode) to find the mass-transfer or kinetic control regions, then playing the deposition at the different regions in constant current density mode, 4), using UV-vis to track the solution change due to the complex formation processes, then finding the best aging time for the electrolyte you want to use, 4) fine-tuning the pH and playing it (some Mn-complexes form in a very narrow window of pH), which is identical to playing the solution chemistry.
It is possible to use constant voltage mode to do a few deposition works, but they are not the normal cases unless you have to accomplish some thoroughly fundamental research works. In those cases, you need a very good (expensive) potentiostat, plus, you have to know the polarization curves in a very broad range extremely well prior to taking attempt to do so.
Good luck!
Possible ways are:
1. Use sand blasted anode if possible
2. Increase the concentration of your electrolyte
3. Increase the temperature
4. Stop stirring
5. Increase the size of the electrode
Good luck!
Making deposition slower may also help. Use the same charge, with less current and increased time.LAyer may grow highly structured, and then be more resistent.
Also, the incorporation of 'finishers' in the electrolysis solution may help, but there is no general recommendation for that, it is just pure experience.
Hi!
I had the same problem of a metallic layer pilling-off GC surface at high thickness.
I had overcome the problem in two ways -
(1) raising the temperature of the solution,
or-
(2) using pulse-dposition
By these means you can control nucleation&growth rates, so you produce smoother and more homogeneous deposits.
however, you will need to do some parametric investigation to find the optimum of your process.
Good luck, man!
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