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Eclectic
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OHHH! Cobalt blue coated Ti electrodes you can wear as jewelry when not electrolysing!
I really like the blue synthetic spinel faceting rough
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Rosco Bodine
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I still think I'd try a cold depassivation of titanium via a titanium cobaltate (? exist ) surface treatment before doing the doped tin oxide baked
coating . My bet is that would be blue colored also .
In another thread I posted a little note about the highly acidic H2CoO3 formation reported from H2O2 plus
Co(OH)2 , and this would seem like a natural for a
cold coating that would protect the Ti from oxidation ,
and then nicely diffuse at the baking temperature to
form a good conductive interface .
Anyway I bet it would be a striking color finish for some of these combinations . IIRC they actually use some of these fired ceramic materials
finely ground as pigments in fancy paints because they have colors and reflectivity which are extraordinary .
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12AX7
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More likely, CoTiO3, analogous to CaTiO3, though Co being in the same class as Mg, Fe(II) and so on, would probably only be stable at high pressure
("enstatite (MgSiO3) is a perovskite-structured polymorph which may be the most common mineral in the Earth", from Wikipedia). Co(III) or Co(IV)
might work in different perovskite type structures though.
Tim
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Rosco Bodine
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@12AX7
What I was thinking was for a low temperature reaction
Ti + H2CoO3 -----> TiCoO3 + H2
And next on baking
3 TiCoO3 -----> Co3O4 + ( 3 TiO1.67 ) conductive suboxide
It would be sweet if it worked
I don't think the temperatures would ever get high enough
for the titanate .
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dann2
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Hello,
I now have SnCl4 in HCl by dissolving Tin in HCl and adding H202. Used 10 grams Tin metal.
I (some days ago) attempted to dissolve some Antimony in HCl. I refluxed overnight but it was not dissolved. I added some Nitric acid and it
dissolved. I evaporated to dryness and got a white powder.
What oxide do I have here??
Sb2O3? or is there anything else?
I attempted to dissolve the powder in HCl (in a heated beaker) but it did not dissolve.
I refluxed some, 3.4g, of the powder in HCl overnight and it did dissolve.
I now have SnCl4 and SbCl3!......I hope.
I will be mixing the "3.4 grams of Sb Oxide dissolved in HCl" with the "10 grams Tin metal dissolved in HCl + H2O2" to give myself a 24% (approx) Tin
+ Antimony mixture.
How do I get rid of the HCl?
I do not want to paint on a mixture contining HCl as I think it will react with the Ti substrate.
I will be using Methanol or Ethanol (+hic#~*!) as a solvent for theses Chlorides.
I am plugging in the oven as you read this>>>>>>>>>
Dann2
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Eclectic
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You can't get rid of the HCl, or your chlorides will hydrolyze and precipitate. Some etching of the Ti is GOOD!. That's exactly what you want to
happen, as the SnO2 will form in intimate contact with Ti metal, and the dissolved TiO2 will mix in as well, forming an adherent, conductive,
chemically resistant, mixed metal oxide coating. Ti is VERY slow to dissolve in HCl.
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dann2
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Hello,
I will go ahead and paint and bake with what I have. I though getting rid of some of the HCl might be a good thing as it would be reacting with the Ti
as I am painting which may be a bad (or good as you say) thing. It is another unknown into the mix.
The Ti I reacted with HCl to make the Oxidizing indicator reacted quick enough. The Ti was hack saw Ti dust. The HCl was hot.
It will get hot when I am drying the 'paint'.
I made myself a Tin/Antimony alloy, 77% Tin, 23% Sb. Placed into HCl and refluxed for about 7 hours. The HCl is getting it very hard to dissolve this
stuff.
I will let it run for another 14 hours or so. Might try some H2O2 or Nitric acid if it does not dissolve.
Dann2
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Eclectic
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Did you granulate the alloy by pouring it into cold water? More surface area/smaller particles is better. Use H2O2 after the tin has dissolved,
leaving the Sb as a fine precipitate. Nitric acid may make unreactive oxides.
You can evaporate the excess water and HCl until your chloride mixture starts to crystallize, then cool and redissolve with alcohols, concentrated
HCl, whatever you want for a more concentrated coating solution.
[Edited on 7-12-2007 by Eclectic]
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dann2
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Hello,
I added the Tin Sb Alloy into the HCl as four pieces about 3 grams each.
The Tin has all dissolved leaving behind a powder of Sb (I presume) I will continue to reflux for some more time.
Does HCl gas escape or does the condenser trap everything?
If the Antimony refuses to dissolve after a long reflux I will add some H2O2 or HNO3. The HNO3 seems to work better at dissolving Sb. Which would you
recommend.?
In another part of this thread someone said the Nitrates (if there are any) would all go away when the stuff if boiled/refluxed.
My SnCl4 + SbCl3 coating that I have already made did not work as a coating for the Ti anode. When baked it did not turn black, as the patents said it
should.
You can rub the coating off.
I put it into a Chlorate cell just to see what would it do and the Ti quickly passivated.
I will start again with new Tin and Antimony (or if the alloy I have refluxing dissolves I will use that) as I have done a lot of toing and frowing
with the stuff I tried on the anode.
With the stuff I have (that did not work) I boiled off some of the HCl but I boiled off too much and got some ppt. I added the HCl back in and
refluxed and got most of the ppt back into solution. I added a tiny amount of H2O2 (+ blue Ti indicator) to make sure everything was oxidixed OK.
Will check oven thermocouple too, to make sure oven is hot enough.
Dann2
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Eclectic
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Pour off the clear SnCl2 solution. Add HCl and some H2O2 to the precipitate and heat for about an hour to dissolve. Mix the solutions back together
and convert the SnCl2 to SnCl4 with H2O2 to avoid a brown-black precipitate.
HNO3 may make insoluble oxides.
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dann2
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Hello,
I got all of the Sb to dissolve my adding a small amount of H202 (down the condenser) without seperating out the SnCl2. Converted to SnCl4. Painted
and baked.
It did not work.
Posted report in Technochem.
Will try homemake SbCl3 + SnCl2 (solid purchased).
Dann2
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Rosco Bodine
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Quote: | Originally posted by dann2
Hello,
I now have SnCl4 in HCl by dissolving Tin in HCl and adding H202. Used 10 grams Tin metal.
I (some days ago) attempted to dissolve some Antimony in HCl. I refluxed overnight but it was not dissolved. I added some Nitric acid and it
dissolved. |
Sounds like a plan . Best to add the HNO3 in small portions
to the HCl . Once you have the antimony in solution ,
leave it in solution
IIRC it takes about 5 parts HCl to 1 part HNO3 .
I'll dig up more and post it later .
Quote: |
I evaporated to dryness and got a white powder.
What oxide do I have here??
Sb2O3? or is there anything else?
I attempted to dissolve the powder in HCl (in a heated beaker) but it did not dissolve.
I refluxed some, 3.4g, of the powder in HCl overnight and it did dissolve.
I now have SnCl4 and SbCl3!......I hope.
I will be mixing the "3.4 grams of Sb Oxide dissolved in HCl" with the "10 grams Tin metal dissolved in HCl + H2O2" to give myself a 24% (approx) Tin
+ Antimony mixture.
How do I get rid of the HCl?
I do not want to paint on a mixture contining HCl as I think it will react with the Ti substrate.
I will be using Methanol or Ethanol (+hic#~*!) as a solvent for theses Chlorides.
I am plugging in the oven as you read this>>>>>>>>>
Dann2 |
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Rosco Bodine
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tin chapter from Gmelin
Here's an oldie but a goodie
http://www.sciencemadness.org/scipics/Tin%20chapter%20from%2...
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