Sciencemadness Discussion Board

Platinum foil

NEMO-Chemistry - 13-8-2016 at 12:47

I cant remember which thread or the site that was linked (i need to chase it back down), but someone gave a link to a very good UK site that sold metal foils.

I have also found an ebay seller that sells stainless steel mesh in many different kinds. These go from 2-3mm gaps between the holes to very fine meshes.

I asked a jeweller in the town and he seems to think he can wrap platinum foil and seal it buy folding and bashing (my interpretation) around the finer mesh grades.

This makes me think it might be possiable to use the mesh covered in platinum foil for making perchlorate's.

The site that was linked too had platinum foil of pretty good thickness for a pretty reasonable price.

Would this kind of approach work? I appreciate i would need to sort out a Tungsten connection etc for the power, but the foil looks like it might hold up well if placed on a good rigid stainless backbone if the foil can be made 'water tight' and the stainless mesh dosnt come into contact with the solution.

The bit that grabbed me was the mesh comes in 30cm X 30cm squares.

zwt - 13-8-2016 at 12:59

Quote: Originally posted by j_sum1  
Quote: Originally posted by Herr Haber  
and gold leaf too, so sad they didnt have platinum, I could have used that!


Here you go.
https://www.goldleafsupplies.co.uk/


NEMO-Chemistry - 13-8-2016 at 13:18

Thanks for the link!!! What do you think of the idea of covering a fine mesh with the foil? as long as the mesh can be covered with joined foils?

Somehow i cant get firefox bookmarks in any kind of reasonable order! they all end up in one huge list!!

I appreciate the effort finding it for me.

[Edited on 13-8-2016 by NEMO-Chemistry]

zwt - 13-8-2016 at 13:39

I think you're on the right track; it's far too thin to be used as an electrode by itself.

I suspect the main problem will be adhering the foil to the substrate. If any solution gets between the platinum and the stainless steel, it will passivate, and you'll eventually (or rapidly) lose conduction. Of course, the only electrodes I've used are gouging carbons and laserred's MMO mesh, though I did get ripped off buying the same "platinized titanium" NurdRage bought. Personally, I'd try folding the platinum on itself to increase the thickness, or wrapping it around a plastic or titanium rod (ensuring at least two thicknesses around the entire circumference), keeping the connection to the power supply above the level of the solution. Alas, it seems they don't ship outside Europe, and I haven't found a comparable supplier for the US.

[Edited on 13-8-2016 by zwt]

NEMO-Chemistry - 13-8-2016 at 14:00

Quote: Originally posted by zwt  
I think you're on the right track; it's far too thin to be used as an electrode by itself.

I suspect the main problem will be adhering the foil to the substrate. If any solution gets between the platinum and the stainless steel, it will passivate, and you'll eventually (or rapidly) lose conduction. Of course, the only electrodes I've used are gouging carbons and laserred's MMO mesh, though I did get ripped off buying the same "platinized titanium" NurdRage bought. Personally, I'd try folding the platinum on itself to increase the thickness, or wrapping it around a plastic or titanium rod (ensuring at least two thicknesses around the entire circumference), keeping the connection to the power supply above the level of the solution. Alas, it seems they don't ship outside Europe, and I haven't found a comparable supplier for the US.

[Edited on 13-8-2016 by zwt]


Surely someone in the Europe would be willing to get some for you and ship it over, ok that is 2 lots of shipping but the weight is low and it would not be a complete porky to describe it as a metal foil sample on the customs form :D.

I dont live near a proper office so use couriers, but as long as you can wait a couple of weeks for postings i would do it.

I am not ordering mine until i chat with the guy who is going to mesh it to the mesh. but once i order some i would ship it for you.

Ironically getting decent reasonable price MMO in the UK is not easy!

Plus you have pool shops!! Not something at all common in Scotland! I envy the pool shops and the chemists delights they hold at good prices lol

[Edited on 13-8-2016 by NEMO-Chemistry]

NEMO-Chemistry - 13-8-2016 at 14:05

I forgot the ebay link to the mesh they sell, they have a great range of various sizes.

http://www.ebay.co.uk/itm/Woven-Wire-Mesh-Sheet-15cm-and-30c...

j_sum1 - 13-8-2016 at 20:16

Quote: Originally posted by j_sum1  
Quote: Originally posted by Herr Haber  
and gold leaf too, so sad they didnt have platinum, I could have used that!


Here you go.
https://www.goldleafsupplies.co.uk/

I have not purchased from them but am impressed with the range they stock. Pt leaf seemed like a good idea for element collection and may have other uses. High surface area is not to be sneezed at.
Tin leaf and other metals might have its uses too.

[/off topic] If anyone wishes to continue this line of discussion then maybe start a new thread and quote this post.


My apologies. I was very conscious when I posted that link that it was in the wrong location, but didn't really have enough to say to justify opening a new thread. I am glad someone has. I would be very interested to see what this product is like. It is a shame that they do not deliver internationally. But if the product is good then there is always a workaround. Pt foil seems like it would be a good addition to an element collection and may have other uses too.

As far as electrodes go, I would be very conscious of liquid getting between the Pt and the substrate with rather negative effects. I can't see any way around that. I suspect a stiff rod would fare better than a mesh -- you cannot improve the surface area using a mesh. The SA is determined by the foil you are using. An inflexible and smooth substrate is going to hold the platinum better. But ultimately you would want to electrodeposit you Pt onto something. That is a process that I know nothing about. And I suspect that it would be difficult to beat the economics or quality of electrodes commercially available.

NEMO-Chemistry - 14-8-2016 at 02:54

Quote: Originally posted by j_sum1  
Quote: Originally posted by j_sum1  
Quote: Originally posted by Herr Haber  
and gold leaf too, so sad they didnt have platinum, I could have used that!


Here you go.
https://www.goldleafsupplies.co.uk/

I have not purchased from them but am impressed with the range they stock. Pt leaf seemed like a good idea for element collection and may have other uses. High surface area is not to be sneezed at.
Tin leaf and other metals might have its uses too.

[/off topic] If anyone wishes to continue this line of discussion then maybe start a new thread and quote this post.


My apologies. I was very conscious when I posted that link that it was in the wrong location, but didn't really have enough to say to justify opening a new thread. I am glad someone has. I would be very interested to see what this product is like. It is a shame that they do not deliver internationally. But if the product is good then there is always a workaround. Pt foil seems like it would be a good addition to an element collection and may have other uses too.

As far as electrodes go, I would be very conscious of liquid getting between the Pt and the substrate with rather negative effects. I can't see any way around that. I suspect a stiff rod would fare better than a mesh -- you cannot improve the surface area using a mesh. The SA is determined by the foil you are using. An inflexible and smooth substrate is going to hold the platinum better. But ultimately you would want to electrodeposit you Pt onto something. That is a process that I know nothing about. And I suspect that it would be difficult to beat the economics or quality of electrodes commercially available.


I agree with what your saying, i saw it as a cheap way to get a job done :D.

I am not 100% sure how to explain any better the way the foil will be attached. I think i need to go back and ask again.

From what i gather the guy is going to roll the foils together with a crimped type fold, he didnt find it easy to explain to me but he is fully aware of what i want it for.

He is confident it can be done and he only wants £5 for doing it! The mesh was his idea, apparently if we pick the right mesh then the foil gets pushed into it (very bad description!).

I intended to use fairly small squares so only 2 foils per electrode are needed. Cost wise this would make it very cheap, i did consider ebay but alot of them seem to be rip offs! I cant afford a mistake like that.

I wanted a graphite rod first, it was the jeweller who said wrapping the foil around a graphite rod wasnt going to give a good seal.

So no idea........But for the money it has to be worth a shot, i am hoping if it fails then the platinum can still be dissolved and used as a plating.

That site has some great products! A really great find. I will let you know how it goes.

careysub - 14-8-2016 at 07:00

How about platinized titanium electrodes commonly used in jewelry rhodium plating? They are also used in various electrolysis processes.

You can get them cheap on eBay from China, but Nurdrage got a fake one once. Buying from an actual jewelry supply place probably guarantees authentic ones.

NEMO-Chemistry - 14-8-2016 at 07:16

Quote: Originally posted by careysub  
How about platinized titanium electrodes commonly used in jewelry rhodium plating? They are also used in various electrolysis processes.

You can get them cheap on eBay from China, but Nurdrage got a fake one once. Buying from an actual jewelry supply place probably guarantees authentic ones.


I also got a fake ebay one, which is what put me off getting another, i paid a fair bit for it.

I also wanted something that would fit nicely into the 'reactor' i am building, a square fits nicely and allows the current to be adjusted by use of a nylon threaded rob.

I also thought the price for the foil was really good and a cheap way to get a decent electrode.

There is 5 leaves of platinum in the book, so two for my trial and if that dosnt work out i have 3 left to try another method.

the beauty of the way the guy intend to fix the foils is that they can be scrapped off easily and used for plating (if i find out how!).

I am also trying MnO2 Anodes and lead nitrate ones (when i make them), the hard part has been sourcing lead!!

Unbelievable how difficult its been to get even small amounts of pure lead around here. It was expensive (relative) but i ended up buying plant weights from an aquatics shop!!

They sell small lead strips in a small container to weigh down aquatic plants, you would think it was gold the price they charge for such tiny amounts lol.

zwt - 14-8-2016 at 07:28

Quote: Originally posted by careysub  
How about platinized titanium electrodes commonly used in jewelry rhodium plating? They are also used in various electrolysis processes.

You can get them cheap on eBay from China, but Nurdrage got a fake one once. Buying from an actual jewelry supply place probably guarantees authentic ones.
You could potentially make 5 beaker-sized platinum electrodes for about $30 with the 5-pack of platinum foil offered by the seller linked above, using the method of wrapping it around a rod suggested by j_sum1 and I. I haven't seen a platinized titanium anode that seemed legitimate for under $30, and I wouldn't consider this source legitimate except it has already been vouched for:
Quote: Originally posted by Harristotle  
I can, however endorse Steve, from Gold Leaf Supplies
His platinum leaf was real platinum, and when suitably supported made a useful electrode. I am going to have to see him about some gold .....
WEB: www.goldleafsupplies.co.uk


[Edited on 14-8-2016 by zwt]

careysub - 14-8-2016 at 11:27

Here is a wild and crazy idea for constructing a platinum electrode using platinum foil.

Use a glass tube, epoxy a copper wire down to where you want the contact with the foil to occur.

Coat the bottom of the tube with electrically conductive epoxy. NOT thermally conductive electrically insulating epoxy! Use the phrase: "electrically conductive" epoxy, with the quotes on eBay for a list.

Wrap the foil around the tube. Exposure of the epoxy through the foil edge should be minimal but some suitable inert edge sealant could be applied.

zwt - 14-8-2016 at 11:38

Sounds complicated. I would just wrap the foil around a suitable rod (perhaps a glass stirring rod, or plastic, or titanium), and use a piece of heat-shrink tubing to secure the foil to the rod and a stranded nickel-plated-copper wire against the foil. With such a design, the connection must be kept above the solution, but it should work for my needs. I suspect ANY conductive material that isn't based on platinum-group metals will passivate or corrode under anodic pressures, even if coated with an "inert edge sealant". Most "sealants" fail quickly when exposed to the conditions of a running chlorate cell or similar.

By my math, wrapping the foil around a 5mm diameter glass stirring rod will give 5 thicknesses around the circumference, which should be enough to pass a reasonable current. It doesn't matter much if the solution gets between the layers of platinum, or between the platinum and the substrate, as long as the substrate is inert and you don't depend on its conductivity.

[Edited on 14-8-2016 by zwt]