Does any one have an idea on electroless copper coating of graphite and carbon based materials? I have obtained good coating but unfortunately within few minutes it forms oxide easily and lose ist metallic nature. Can anyone explain how can i prevent it? I have used copper sulfate, sodium potatsium Tartrate, sodium hydroxide and formaldehyde solution for elctroless plating.
What kind of thickness are you depositing? It is very difficult to not have at least a superficial layer of copper oxide forming on copper deposits once you expose them to air, but if you have thick deposits, although the top might oxidise, most of the deposit might remain as metallic copper underneath. The option of vaccum drying suggested above does seem like a good idea, as you'd avoid having oxygen whilst heating up, the combination of which really encourages oxide formation.
There are aditives you can add to your bath to avoid oxide formation during deposition, but from what you describe, the oxidation seems to occur after you deposit, so your pre-treatment and deposition procedures are probably just fine and it's post-treatment that you should look at.
Did you do a surface treatment of your graphite and carbon based materials?
i just dried the samples at 110 deg for 20 mins.... before that i cleaned with distilled water after coating. Thats it
A long time ago I have done Cu precipitation on polycarbonate substrate. It stayed metallic for the duration of the experiments that I was running, so that is possible. But I just vacuum dried it at room temperature. Maybe try that instead of 110 oC bake.
Also, are you sure you're forming an oxide? It could be a carbonate in combination with hydroxide. If i remember correctly, i didn't add hydroxide to the Cu plating bath that I've used. Maybe that could make a difference, but I'm spitballing here.
I don't have any experience in Cu coating on graphite but I used to plate Cu on polymers by electroless.
Can you deposite copper on graphite/carbon based materials without any surface treatment?
In the case that we did not dry the sample surface correctly, the deposited copper color turned from the metallic (!) to oxide (!) (visual observation). But in our case the surface was treated with some chemicals prior to electroless metallic bath.
Prior to coating we did activation with SnCl2 aand PdCl2 acidic solution.
What kind of thickness are you depositing? It is very difficult to not have at least a superficial layer of copper oxide forming on copper deposits once you expose them to air, but if you have thick deposits, although the top might oxidise, most of the deposit might remain as metallic copper underneath. The option of vaccum drying suggested above does seem like a good idea, as you'd avoid having oxygen whilst heating up, the combination of which really encourages oxide formation.
There are aditives you can add to your bath to avoid oxide formation during deposition, but from what you describe, the oxidation seems to occur after you deposit, so your pre-treatment and deposition procedures are probably just fine and it's post-treatment that you should look at.
The thickness is about 40-100 µm. I face major problem with graphite materials. With polymer substrate the formtion of oxide is very slow, while with graphitic substrate ´the coating forms oxides within few (1-2) hours. Also the oxide layer Formation was confirmed by XRD.
However will do vaccum drying and check!! Also planning to use antioxidant after coating. Can anyone help me to choose good antioxidant?
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