I want to determine if a particular metal can be electrochemically deposited on another in the form of thin film.
you can do a voltammetric scan of the metal that you will deposite than choose the reduction potentiel appearing and applied it
Based on my limited knowledge from the literature, we can only predict such deposition preference if the deposition solution contains a mixture of multiple metal ions. In that case, deposition of more noble metal will be diffusion controlled and will result in an alloy. In order to get multilayerd deposition of two or more metals, there are two ways to follow.
(1) Use separate baths and perform sequential deposition of one metal after the other. This route is cumbersome.
(2) Use single bath containing multiple metal ions but in this case one needs to adopt pulsed polarization approach in which the potential is varied in a way that only one particular metal gets reduced at a certain potential. This will give rize to nearly pure layers of each metal.
I would welcome any comments.
Cyclic voltammetry -- see my papers on Electrochemical behaviour of copper complexes -- and many other papers--
Copper -NTA complexes ; papers on anodic dissolution of binary alloys
On the practical point of view (galvanic electroplating) the problems arise only in the case of easy to oxidate base materials (titanium, aluminium, berillium) and when the metal to plate has a potential higher than the base (i.e. copper on iron...) other problems arise if in the solution there is the possibility of redox reactions, in my opinion has to be studied case by case
You can calculate the the thermodynamic equilibria for both metals and their possible reactions in the media you are using. With this you will see the regions of predominance of soluble species as well as the regions of tability of the solids. You can use the Purbaix book (Thermodynamic equilibria in aqueous solutions) as a guide, or simply use commercially available software. Of course, you have to take into consideration that this is only ccounting for thermodynamic feasibility and has not much to do with kinetic rates.
ok Xochitl Dominguez-Benetton
but the things are not so easy
there are over voltage on metals( substrates)
run a CV
Indeed there are overvoltages, but the equilibrium diagrams are very useful even with the overvoltages! There will be a shift in the potentials in the experimetnal system, yet the equilibria are still valid if calculated properly (i.e. considering all the species available in the real experimetnal system). Things are even much more complicated than the overpotentials alone, there are current and potential distributions over the whole electrode surface.... The thermodynamic equilibria will only be helpful to determine if the one metal in question can be deposited over the other, meaning that the metal working as substratum will be stable at the given conditions in the presence of the metal to be deposited, and that the metal to be deposited can form a stable solid under the same conditions. Once that the thermodynamic feasibility is established, then other aspects can start to be considered to setup the appropriate experiment.
Running a CV is a good idea for some metals and some substrates, but here we do not know if the substrate is a porous electrode or if the metal is lithium or a lanthanide. The CVs will show nothing relevant if those are initially as ions in an aqueous solution. You would only see hydrogen evolution at the range of potentials of interest for electrodeposition.
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