Cobalt Oxide Anodes

Hang on! I thought you said Mn and Co Sulphate bath. Thats a big difference. What does the ethanol do! I've only got denatured!

I'm a bit thick......

You'll need to specify exactly what you want me to do!

[Edited on 8-12-2007 by Xenoid]

tin nitrate hydrogel complex with M2O3 forming nitrate

Yes, I realise the importance of current density.

What I was getting at is that if you imagine the cell as a chain of resistances for example going from the "metal part" of the anode through any "surface layer" through the electrolyte, through any cathode layer and into the cathode metal...... Duh!..Duh!..Duh!... Ohm's law, so long as you have the same current density the voltage drop across any surface layer will be the same no matter what the rest of the cell resistance, I was thinking increasing the voltage across the cell would increase the voltage across the "surface layer"..... Bangs head on wall and goes and stands in corner with dunces hat on..

"Did you get an oxide coating on the Ti from the AC?"

The etched Ti went in light grey and came out slightly darker grey, probably just the colour of the solution.

Oh, why do these electrodeposition processes never work for me ...
I think I'll go back to baking!

One guaranteed way of coating a cobalt spinel anode
interface without getting permanganate forming is baking on the MnO2 as the pyrolysis product of Mn(O3)2 ,
Co(NO3)2 and Pb(NO3)2 , while humming a few bars
of "I'm looking over a four leaf clover "

But I still think that some SnO2 is probably going to be needed somewhere as a sealing and barrier layer and possibily as a bonding layer in the MMO scheme .

A lot of industrial chemists have been trying to crack this nut
for a long time , and I think that we are about as close to accomplishing that as anybody has gotten . I really do
think that old ancient article about Sn nitrate complexes
with M2O3 precursor nitrates leading to soluble hydrogels
is an overlooked and crucial piece of "lost art" that can make this whole baked MMO anode architecture actually work .
This may be another one of those cases where the more modern chemists get humbled by a bit of technology from
great grandpas era making a timely visit to today
This could be just the needed "glue" that sticks this whole
thing together .

BTW , this hydrogel stuff might bake onto graphite also
or maybe even onto copper , nickel , stellite rod , iron , aluminum , stainless steel , ect.

One of the things I was thinking when I saw the bimetal
spinels of Co with copper and zinc and nickel is that there seems no reason whatever that simply painting Co(NO3)2
onto such metals shouldn't result in a bonding interface
of those bimetal spinels with those same metals indigenous
oxide coating . This makes copper a candidate substrate ,
simply by dipping it into nitric acid and then painting it with
cobalt nitrate and baking . I'd bet good money on it .
Got copper rod or busbar barstock ? How about a piece of copper pipe , maybe split lengthwise and smacked flat .
Spinel interface that material , then do the SnO2 hydrogel
barrier coating and then apply the
MnO2+Co(NO3)2+Pb(NO3)2 working coat . 1-2-3
and you got a copper substrate perchlorate anode

OTC copper is soooo *not* titanium . But sealed up good
enough it could work just the same . And that sure would simplify everything .

And for aluminum , the hydrogel would be the interface
coating , rather than the spinel . The hydrogel would be
the one based on aluminum nitrate and stannic nitrate ,
and hopefully would result in a solid solution interface
on the aluminum . Here again , go right on top of that
with the Mn/Co/Pb nitrates baked working coating
and 1-2 you have an aluminum substrate perchlorate anode . Cute huh ?

Conductivities not being good enough or porosity problems would seem to be the only obstacles which could trash these schemes . But I have a suspicion they could be made workable schemes . Just a matter of getting the required chemistry for the coatings right .

[Edited on 9-12-2007 by Rosco Bodine]

Cobalt Spinel on TiH2 US4222842

Summary of Co Electrodeposition.

Well, my next move is back to baking! I'm very impressed with the way the Co oxide (spinel) is holding up it the chlorate cell! It has now been running at about 56mA/cm^2 for 72 hours (3 days) with no variation in the electrical parameters, the coat is still hard!

I have a Ti rod which has been hydriding for about 48 hours

I am currently making some more Mn(NO3)2 by double dissolution. This time I will recrystallise it to purify it. I may make some Zn-nitrate as well!

I have aquired a small quantity of nitric acid, which I intend to use to make some small quantities of Pb-nitrate, Sb-nitrate and various other "exotic" nitrates for doping experiments.

Here's a paper I'd like to get.

I just saw a reference to this paper. It looks like something we'd be interested in. Maybe I'll try to email the authors and see if I can get a copy.

Something else I was thinking about :

With the 4 coat baked spinel anode lasting (probably) at least 4 days, and 12 coats seeming to be the norm for the number of coats used by industry. Testing is going to start taking a long time. I'm thinking of limiting the number of coats to 2 or 3 (just enough to provide a good seal) and/or increasing the current density, if some particular combination looks promising then it can be subjected to longer testing.

Otherwise, unless someone else joins this quest, I am going to run out of power supplies, etc. there is a limit to the number of (per)chlorate cells that I can have "bubbling" away here!

@ jpsmith123 - Re microwave heating, good idea, may get too hot, too fast! Have to be done on low setting. Rather your microwave than mine for testing...

[Edited on 9-12-2007 by Xenoid]

I just went down to check on my remaining Co - nitrate concentrate which I had left in the fridge, at about 0 oC. It has crystallised nicely after about 3 or 4 days, leaving about 40 mls of supernatant liquid (containing impurities... ) which could be poured off, and the crystals drained. They really are a pleasing colour! And not so difficult to crystallise after all.

Image shows cobalt nitrate hexahydrate crystals in the bottom of the SS evaporating saucepan. Diameter of crystal mass is ~ 13cm, depth is about 4mm.

@ Dann2

Sorry Dann2 I beat you to it, been there, done that, with gouging rods!

I started a Li (per)chlorate cell back on the 27th Nov. It's been running for over 13 days now. I made the LiCl via a fairly stoichiometric conversion of the carbonate with HCl. I ended up with ~250g of LiCl in 800mls H2O after filtering. I boiled this down to 600 mls and used 400 mls in the cell ( ~ 160g LiCl).

The cell is a funny little design, with 4 half-length gouging rods, and a central SS sheet for a cathode. The cell is shown below just after start up. It's running at about 3.5 volts and 3 amps and the electrical parameters haven't changed since I started it. I haven't been paying much attention to it, what with all the Cobalt excitement, other than adding water. I was planning on running it until the gouging rods disintegrated to see if any perchlorate was made. It should happen soon!

Because of the "light weight" of Li adding 3 or 4 oxygens makes a big difference to the weight. I did a rough calculation, based on starting with 100g of Li2CO3 assuming 100% conversions you will get 115g of LiCl, 245g of LiClO3 and 288g of LiClO4 which will convert to 375g KClO4.

I'm not entirely sure what I'm going to do with this cell when it finishes, it seems to be pretty inefficient, when I started it, I had magnetic stirring, but it kept spinning out so I gave up on it!

[Edited on 10-12-2007 by Xenoid]

Hello,

Tidy cell, not able to see the humurous side of it, but never mind.
I presume the picture of the Cell was taken just after you made it. (No black mess)!!!
The patent states that current density should be between 150 and 250mA per square cm. Perhaps it is not important. The patent used Pt as the anode anyways so it probably does not apply to C or DTO or whatever we are using.
The most colourful version of the patent on the net is here:

http://www.geocities.com/CapeCanaveral/Campus/5361/chlorate/...


I will be an extremly angry and bitter little man for a month or so since I was beaten to it, but that's life.

Will be using DTO so perhaps it may be interesting. Was going to use graphite (thankfully I did not) but the DTO was to hand and handier.

I guess the Zr Nitrate project is not as simply as I had speculated.

Dann2

Hi guys,

Here's my latest Co oxide (spinel) anode, it's smoooooth, shiny and HARD.

Despite what I said in various previous posts I decided I had to go the full way and see what 12 coats looked like - they look good! It took most of the afternoon but I think it was worth it!

I used a 50% cobalt nitrate hexahydrate solution.

A few minor differences from the previous anodes;

1) The anode was hydrided after etching.

2) The anode was hung from the top of the heat gun tube, this is less clumsy and gives better access than my previous arrangement. I think the heat distribution is probably a little more even as well.

3) I gave the anode a bit of a wipe (almost a polish) with a soft cotton cloth, between coats, to remove loose dust. My feeling about this was that it would help to make the coating more compact.

4) To speed things up, I did a few minutes cooling in the fridge, and then when still warm to the touch, did the dipping!

I did a quick check to see that it was working by putting it in a perchlorate cell. I set the current density to 50mA/cm^2 voltage was quite low, 3.7 volts, bubbles and ozone.

I'm open to suggestions as to what to do with this anode (NOTHING RUDE PLEASE). I would like to put it back in a perchlorate cell, as, quite frankly, I think chlorate cells are a "piece of piss" for these anodes or will eventually prove to be so!...
If anyone has any suggestions for a simple baked on doped overcoat I will try it, otherwise I'll just put it in "as is" and run it to destruction..

The other 4 coat anode in the chlorate cell is still running fine, the coat is wholly intact, but is possibly starting to thin in places (like my hair). There seem to be a few more bits of black floating around. It's been going for 4 days and 6 hours now.

Quote:

If anyone has any suggestions for a simple baked on doped overcoat I will try it, otherwise I'll just put it in "as is" and run it to destruction..

Conclusions from the Mn-Co Oxide Coatings Power Point presentation

Hello.

Good Anode, I have kept the picture for my ambum (if you don't mind)!

When you say that a Chlorate cell is a 'piece of piss', do you mean that the anode will make Chlorate easily or will easily stand up to the Chlorate cell (or both).
I am inclined to think that a Perchlorate cell is not any more corrosive to anodes (except Graphite) that an Chlorate cell . I fact a Chlorate cell is harder on Lead Dioxide but perhaps I am talking through my hat, guessing really. In industry ALL Chlorate cells are pH controlled and this (I think) makes them less corrosive generally. Your Chlorate cell will not be pH controlled. Of course if an anode does not make Perchlorate then there is little point in worrying if it corrodes or not in a perchlorate cell.
Will Cobalt Oxide make Perchlorate? I reported some time back that it did but then later when I discovered that my plated-on Co Oxide coat had worn off, I was not 100% sure if it was the Co Oxide or the exposed DTO that made the Perchlroate.
Go with a Perchlorate cell and see will it make Perchlorate at a reasonable effeciency.

Of course if you are looking for a good solid overcoat, you could try a good thick coat of a substance with a formula of..................................PbO<SUB>2</SUB>.

You could also try a Chlorate cell and try to go all the way to a low concentration of Chlorate (to end of Perchlorate cell) to see has Cobalt Oxide 'HOLY GRAIL' status.

Still drying my Co Nitrate crystals to weigh them.

The paste is a good idea. Seen it too. Will try. No fumes, no heating, fast, OTC, ....QED.

Dann2

"piece of piss" - Australian / New Zealand saying, it means "easy"

@ Dann2 - Well I think my first attempt, 4 coat anode is lasting very well in a chlorate cell. I think that with a full coating, doping, different layers and treatments it will not be too difficult to make an anode that goes full distance in a chlorate cell or lasts for 2 or 3 cells.

On the other hand, the Co oxide anode only lasted 14 hours in a perchlorate cell, and even then I'm not sure it was producing perchlorate efficiently. So I think more experimentation is needed with the perchlorate aspect, I'm sure we can sort out any problems with the chlorate...

BTW - I wouldn't worry about trying to dry the cobalt nitrate, I just used moist, drained crystals, with an equal weight of water. I don't think the concentration of the dipping solution is all "that" critical!

[Edited on 11-12-2007 by Xenoid]

Chlorinator Disassembly

Well, I decided to have a go at disassembling the chlorinator top! The blue plastic cover came off fairly easily, with a bit of cutting, exposing the epoxy potting medium. This stuff is tough and brittle at the same time. It cuts with a hacksaw, but when you hit it with a hammer and chisel it splits with a conchoidal fracture and flies in your face. I guess it's like the epoxy dentists use for fillings. I've managed to get about a third of the way through it and expose the bent over tops of two electrodes. I've also been able to remove a 12mm x 100mm Ti strip that was being used as a support and some sort of earth/guard electrode. In the image it is shown lying across the top of the assembly. It will be useful as a test electrode for coatings. I think I can get this all apart, eventually!

Quote:

Quote: [ On the other hand, the Co oxide anode only lasted 14 hours in a perchlorate cell, and even then I'm not sure it was producing perchlorate efficiently. So I think more experimentation is needed with the perchlorate aspect, I'm sure we can sort out any problems with the chlorate... [Edited on 11-12-2007 by Xenoid]

It was my third anode, the one with 8 coats (but the dipping solution was only 25%). I guess the coat thickness should have been the same as the 4 coat anode (50% dipping solution). It basically just wore away, it didn't flake off.

I'm wondering how the wear rate relates to coating thickness and whether it's linear or not (hopefully not). If it's linear and a four coat anode lasts for 4 days, then a six coat anode will last 6 days etc. etc. Hopefully it's more like 4 for 4, 6 for 8, 8 for 16, 10 for 32 or possibly much, much, better than this. It's just going to be matter of testing and more testing.

I'm inclined to put my latest 12 coat anode in a perchlorate cell and just let it run, this way we can get some good basic information about optimum numbers of coats and the way they build up wear resistance - is it a linear or perhaps an exponential process! I think it's best to do this "basic research" first on the "plain" Co oxide, before trying more exotic procedures. The more contributing, the faster this will get done! If we don't have this initial basic research it's going to be hard to make comparisons between different procedures.

If everyone who is having a go at this could stick to a 50% Co nitrate solution and bake at 370 oC. we can soon build up some baseline information on the longevity or otherwise of simple Co oxide coatings. If some could try 6, 8 or 10 coats in both chlorate and perchlorate. We can then plot some curves to which we can compare "modified procedures" - and there is literally no end of them....

[Edited on 11-12-2007 by Xenoid]

Eh!..what... Is that Co nitrate or Co carbonate.... an inauspicious start...

The 4 coat anode in the chlorate is still OK after 5 days, the electrical parameters are still the same as when it started. The anode is definately eroding though, there are some thin areas, and there is now more black gunk floating around. I think it may only last for a few more days!

What is really needed is a set up for doing multiple anodes, say 6 at a time. I'm still looking at toaster ovens in this regard. I've had two over 300 oC. without adding extra elements, so it looks promising!

Thanks 'spoons, I've finally got them apart. The epoxy never got to a "jellyish" state, it softened slightly, and then went a bit crumbly. I'm glad it wasn't a transformer I was removing, I had to apply a lot of heat!

Here's the separated electrodes, I will leave them like this until I come up with a cell design, at least each individual electrode can now be cut off, and have its own reasonably long, bent over attachment tag!

Sure isn't a holy grail...

I put my beautiful, smooooth, shiny and HARD anode with 12 coats in a perchlorate cell! It has been running for 15 hours now. A lot of black material has come off, and a thin patch has appeared....

This cell initially ran at 3.7 volts and 1.12 Amps (50mA/cm^2) and seemed to produce a lot of bubbles and ozone! The voltage has now dropped to 3.6 volts, (at 1.12 Amps) it is only producing a thin stream of small bubbles, so it looks like it is making perchlorate. I am very disappointed in the way plain Co oxide is performing (lasting) in a perchlorate cell, although it does seem to be making the right stuff! Perhaps I rubbed off too much oxide, with my vigourous polishing between coats!

The 4 coat anode in the chlorate cell is still going well, although the current has dropped slightly ( 1.87 --->1.84 Amps). I feel the "end is nigh" for this brave little performer, and it's downhill rapidly from herein!

No real surprise there

Cobalt spinel has never been purported nor advertised
as being a working anode coating . It is an interface
material , a TiO2 dielectric nullifier , a rectifying junction
discombobulation reagent , anodic current facilitator ,
as opposed to an irish tater .

Sooooo what alloy Ti rod is being used for your redundant proof of this ?

I wouldn't have a clue, I bought it from some guy on the local trade site. He owns a sports store, so he may have been importing Ti products for bikes, experimental fishing rods, etc. He's a bit paranoid and wont tell me anything.

I already answered this, but forgot to post it, sorry....

I guess that is 6% Al and 4% V, what is the composition of electrode Ti, any difference! I gather Niobium and Ti/Nb are in use!

Well I still have plenty of enthusiasm...

These have been my most successful atempts yet! We are just scratching the surface (no pun intended). I still have heaps of things I want to try, I am just getting some "exotic" nitrates together first. I think it is important to get the basic techniques correct first! For, example my first coat, always looks crappy, and this is the most important one. It is probably easier to see defects, than with later coats which are over black oxide. It may just be useful to try a series of tests (using different conditions) with single coats., to see which performs best.

Quote:

Originally posted by Rosco Bodine No real surprise there Cobalt spinel has never been purported nor advertised as being a working anode coating . It is an interface material , a TiO2 dielectric nullifier , a rectifying junction discombobulation reagent , anodic current facilitator , as opposed to an irish tater . Sooooo what alloy Ti rod is being used for your redundant proof of this ?

Regarding the Discombobulator, my Uncle used to use one of these very useful devices but the wheel eventually fell off it.

The patent have shown (pure) Co Oxide (making Chlorine anyways) to have worked for 250+ days continous with only a small rise in voltage. I call that success. They were not making Perchlorate though. Perhpas it is much 'easier ' on an anode making Chlorine in a controlled Chlorine cell as opposed to making Chlorate in a non controlled cell (High pH). None of the Co Oxide patents have used the Co Oxide to make Chlorate (in a controlled cell or other wise) that I am aware of.
Some of the patents have sang the praised of Zr in conjunction with Co in the spinel but the examples at the back of same did not show a Zr containing spinel doing anything out of the ordinary that I could see.
The patents are obsessed with voltage accross cell = power used. This is not so important to us. We want a long lasting anode, a volt or so is not a problem.

Zr is the answer I tell you....

Dann2

Quote:

Zr is the answer I tell you.... Dann2

There is little or no reason in the literature to believe that will prove true . I'm am not trying to discourage you , but
that spinel interface is just that , not a complete anode .
It's like driving a car away from the body shop after they put the primer coat on , and saying it's painted good enough
before the finish goes on . Maybe a bit impatient ?

YGTFR !

Quote:

Hello, Quote: Originally posted by jpsmith123 If you look at patent #3632498, you'll see that Beer mixes TiO2 up with everything but the kitchen sink (e.g., gold, iron, lead, ruthenium, etc). I LOVE IT!!!!!!!!!! Could not agree more. The company he left to go to Diamond Shamrock are still hitting themselves. Quote: Originally posted by jpsmith123 snip I don't know if it makes sense, all I know is that one of the most successful inventors claims that it works; so I'm just saying, I think it's worth a try.

it's deja vu all over again

Well that settles that , huh?

How could I possibly dispute the science .

You are absolutely not reading the patents with comprehension , but are picking out what you want to believe in different terms and out of context from its meaning .

I'm not even going into it more at this point .

And have you checked the price on Zirconyl nitrate ,
or is it that you think just dumpng in some Zirconia ,
maybe cubics well ground to powder is what is needed ,
why not cabosil or just sand ought to work its just a filler right , no real chemistry involved there .

[Edited on 13-12-2007 by Rosco Bodine]

Hi guys!
I do not know whether it is suitable to poster here about the PbO2 anode, I really want to share some my experience about anode preparation here.
I have made several PbO2 anodes before.
1, Ti/SnO2+Sb+MnOx/PbO2
2, Ti/SnO2+Sb/PbO2
3, Ti/SnO2+MnOx+Y/PbO2(quite well)
4,Ti/SnO2+CeO2/PbO2(have the shortest service life)
5, Ti/SnO2+sb+CF/PbO2 this one is prepared by others in my lab, (CF=Carbon fiber, this one is said to be the best)
some one tell me the Ti/SnO2+Sb/alfa-PbO2/belta-PbO2 is also very reliable.
I have made other anode such as DTO,I have not made Co3O4 anode before,(my job is watertreatment using Ti/PbO2 or Ti/SnO2, and study the mechnism of solid solution oxides in anode)I do not know why your guys made Ti/Co3O4 , what it use for? for using in Cl2 evolution or Perchlorate electrosynthesis?

Quote:

Originally posted by Rosco Bodine Quote: Originally posted by dann2 @Rosco For example the DTO (for anodes) has always had a high Sb content with HCl in the precursor. SNIP Is there anywhere (patents or journal article or elsewhere) where a sol-gel or mixed valency inorganic polymer has been reported as useful as a way to make an anode, experimental, industrial or otherwise? Dann2 Well that settles that , huh? How could I possibly dispute the science .

Yes

By 'Boo Hooing' the examples in the patents or suggesting that the patents were 'cobbled together in a hurry' you are in fact contradicting people who have spent a hugh part to their professional life making actual successful anodes. Beer (and the patent people we are quoting here) know more about anodes that all the people on this discussion put together. Thats my opinion, feel free to disagree.
I am not trying to suggest that I have comprehension of all the parameters, processes, chemistry etc.

Sol-Gel and Mixed valency inorganic polymer for anodes?
If I see a single example (or a hint of an examply) for a anode I will withdraw the shaking head.
That's a good deal.

Quote:

Originally posted by Rosco Bodine And have you checked the price on Zirconyl nitrate , or is it that you think just dumpng in some Zirconia , maybe cubics well ground to powder is what is needed , why not cabosil or just sand ought to work its just a filler right , no real chemistry involved there . [Edited on 13-12-2007 by Rosco Bodine]

Quote:

Originally posted by R.P.Wang Hi guys! I do not know whether it is suitable to poster here about the PbO2 anode, I really want to share some my experience about anode preparation here. I have made several PbO2 anodes before. 1, Ti/SnO2+Sb+MnOx/PbO2 2, Ti/SnO2+Sb/PbO2 3, Ti/SnO2+MnOx+Y/PbO2(quite well) 4,Ti/SnO2+CeO2/PbO2(have the shortest service life) 5, Ti/SnO2+sb+CF/PbO2 this one is prepared by others in my lab, (CF=Carbon fiber, this one is said to be the best) some one tell me the Ti/SnO2+Sb/alfa-PbO2/belta-PbO2 is also very reliable. I have made other anode such as DTO,I have not made Co3O4 anode before,(my job is watertreatment using Ti/PbO2 or Ti/SnO2, and study the mechnism of solid solution oxides in anode)I do not know why your guys made Ti/Co3O4 , what it use for? for using in Cl2 evolution or Perchlorate electrosynthesis?

Quote:

Originally posted by R.P.Wang Hi guys! I do not know whether it is suitable to poster here about the PbO2 anode, I really want to share some my experience about anode preparation here. I have made several PbO2 anodes before. 1, Ti/SnO2+Sb+MnOx/PbO2 2, Ti/SnO2+Sb/PbO2 3, Ti/SnO2+MnOx+Y/PbO2(quite well) 4,Ti/SnO2+CeO2/PbO2(have the shortest service life) 5, Ti/SnO2+sb+CF/PbO2 this one is prepared by others in my lab, (CF=Carbon fiber, this one is said to be the best) some one tell me the Ti/SnO2+Sb/alfa-PbO2/belta-PbO2 is also very reliable. I have made other anode such as DTO,I have not made Co3O4 anode before,(my job is watertreatment using Ti/PbO2 or Ti/SnO2, and study the mechnism of solid solution oxides in anode)I do not know why your guys made Ti/Co3O4 , what it use for? for using in Cl2 evolution or Perchlorate electrosynthesis?

Please enlighten us, we are all ears!

It's all very well, creating exotic anode coatings in a fully equipped laboratory, with access to high purity chemicals and scientific literature. I'm sure any competent chemist can accomplish this! Unfortunately we are not competent chemists (well I'm not anyway)...

What we are trying to accomplish is anode coating preparation from relatively easily obtained chemicals, using simple techniques and equipment.
If your procedures satisfy these criteria, please let us know, or start a new thread outlining them. But really it needs to be something the average amateur chemist can do in the kitchen, garage or backyard shed. Anything else isn't really relevant as far as I'm concerned. Most of us don't even have access to lead ccompounds, strong acids or sophisticated facilities for plating.

Again, if what you are doing is simple, please let us know!

Edit: Actually if they are basically PbO2 electrodes, please post your procedures and techniques in the "More on PbO2 Electrodes" thread. We look forward to seeing them...

[Edited on 13-12-2007 by Xenoid]

Yes!...Yes!...Yes!...

I'm getting there!... I'm getting there!...

Do you realise how difficult it is to make and purify Mn nitrate (this stuff decomposes when you look at it the wrong way and has to be stabilised with nitric acid) and other nitrates! Give us a chance!... I do have to mow the lawn and do the shopping!...

Hey yeah that's me too ! I have a downed tree from a storm still laying on my lawn , my dogs need baths ,
and I'm dealing with a couple of inept attorneys who
can't read statutes unless the price of reading fees is
agreeable and negotiated on a word per word basis
I stay ass deep in alligators , but keep shooting , hoping
alligators get short before ammo

IIRC , a carbonate intermediate may be the way to go
there with the Mn . Or perhaps decomposition of some permanganate and then cycling to a nitrate would be
better than ever working from sulfate , I'm not sure .

I'm slower than Christmas for not having everything on hand myself , and otherwise being occupied , but will get around to experiments too when I can . Anyway , nobody put on the blinders and get tunnel vision about any one
patent or any one "recipe" , as there is more than one way to skin a cat , some maybe not even invented yet till the next cat comes along

Many chemical processes have highly branched "flow charts" for possible routes from various starting materials
to various end results so nothing is necessarily written
in stone as one and only right pathway of doing something .

Short-lived as they have been, the Co oxide anode has produced perchlorate (as tested with methylene blue). I have no idea about the amount or efficiency. Anyway it's irrelevant as we'll be putting something over the top...

@dann2

This is a *science* forum , not a let's all be copycats
of what patent xyz declares is the "ultimate truth" ,
being some witless coven of cauldron stirring drones .

You don't understand the reaction mechanisms
that are applicable or you wouldn't be making
the arguments you are making , which are
pseudoscience . Unproved yet well founded
scientific hypotheses are a hell of a lot more
substantive than "speculation" . For you it
seems that a patent you like is the bible on
some peculiar aspect of a much broader technology .
Where you can find a common denominator in
more than one patent , you *assume* that
somehow proves that represents the "state of the art" ,
even though no data is presented to suggest that .
If you read carefully , the very language
of patents is often ambiguous , and deliberately
so , as to "precise recipes" which may be closely
guarded trade secrets . Being skilled in the art
begins with understanding mechanisms for
certain reactions , getting the point of what
is the general idea , you then see many variations
on a theme and that the claims of a patent
try very hard to cover the range of those variations
without ever actually being specific about
*precisely* what is "preferred" ......because
that is for them to know , and for you to try to
figure out If you take the rote description
they give as your blueprint for duplication of
their proprietary technology , then you are
kidding yourself .

Don't despair over spinels ,
perovskites are just around the corner

[Edited on 13-12-2007 by Rosco Bodine]

I can assure you, that only for the examples at the end of the patents there would be a mountain of mountains to climb to get to working (or close to working) anodes.
If all patents put up to this board had the examples snipped out, there would not be much actual progress on the anode front. (It a war you know ). IMHO. Lots of discussion maybe.
Not trying to suggest I am some sort of scientist capable of an understanding of all the fields we are touching on here but I do know that at the end of the day we need an actual working anode. Do you have a good enough understanding of the workings of possible recipts of baked on coatings on different substrates, working in different mediums doing different jobs to suggest that worked examples (in for example the Diamond Shamrock patent) are rubbish?
I have me doughts.
You know more chem. than I do, that's certain.
If people are actully using the examples to knowingly mislead, that is a different story. I do not think they do.

Experience from other people (amateurs where we are) is also very inlightening, irrespective of whether or not they or us understand the science.
I would be attempting to put LD on Graphite bare Ti, Iron and other attackable substrates and expecting a good result if I lisened to the 'science' alone.
It can be done of course, so long as you wheel out the big tanks, lots and lots of equipment, lab grade chems., triple distilled water......

Perhaps I am droning on.........or am I bringing home the honey!!!!!!!!!!!!!!!!!!!
Naturally enough I will vote the latter


Dann2

I must admit:
PFP
<B>
This is a *science* forum , not a let's all be copycats
of what patent xyz declares is the "ultimate truth" ,
being some witless coven of cauldron stirring drones . </B>

PFP?? Pure f*^k)%£ poetry

[Edited on 14-12-2007 by dann2]

Glad someone's working around here...

Meet Gertrude, my latest anode. She's blue/black, smooth, very shiny and hard!

Gertrude has a double layer Co-spinel INTERFACE and 8 layers of beta-MnO2 on top!

Well, Gertrude say goodbye my beauty, because you are off to see the nasty perchlorate cell for several hundred days of exhaustive testing!

But before we do that!

Can someone verify my understanding of oxygen overpotential (OO) in relation to a perchlorate cell! As I understand it, a material with a high OO is desirable because it allows one to use higher current densities generating perchlorate before energy starts being wasted making oxygen! When running a perchlorate cell, should we increase the current density to a point just where oxygen starts to be evolved, or a little higher. In the past, with my platinised electrode, I just turned up the juice to what I thaought was a suitable current density, and to hell with the amount of oxygen produced. In retrospect I guess this was the wrong approach!

I'll follow up with details, after the exhaustive testing if it is warranted.

@dann2

Patent examples are usually illustrative of general principle , a sort of proof of concept presentation , while the secret 11 herbs and spices they keep to themselves .

I don't think the anodes described in shamrock or in many other patents are rubbish but their methods are not as advanced as those methods and chemistry which we are
making the greater interest of investigation and experimentation . Never hurts to try applying newer information or more advanced methods to older processes . You don't seem to understand why the methods being explored by us are more advanced and probably superior . What we are doing is a bit of updating of some *old* methods .

I wondered why you seem to be playing the devils advocate a bit , maybe the idea was stirring the pot ??? Because I thought the aim here was to
"think outside the box" and try to come up with something more predictable in the way of a system for anode assembly from the substrate up . Applying a spinel thin film MOS technology to the substrate / interface seemed like a reasonable "breakout" from the other stuff .
As for the applicability of the technology to perchlorate anodes , well no the scentific literature wasn't really specific nor excluding either in that potential use , but
neither was it limiting or specific to *any* particular use .
So if you basically have a hermetically sealed metal and ceramic anode core , then it becomes a matter of what sort of working coating is applied last that defines what
the completed anode is useful for electrolysing . The
core structure is pretty generic and could be overplated with just about anything you want , for making any sort of anode you want for whatever kind of cell , perchlorate included . Some of the designations for these things
don't even get as specific as to call them anodes , but simply call these cores something like "electrodes for electrolysis" and say no more .

About the substrate glass versus titanium , it isn't
really what it appears because for the SnO2 coatings
the interfaces are SiO2 for glass and TiO2 for titanium ,
and silica and titania are not that disimilar , as would
account for any vast difference in coatings performance
including conductivity , which is the aim . Just because
Pytlewski didn't bake and test the conductivity for the
polymer coatings doesn't change the chemistry of the
polymer which would necessarily make it a precursor .
It already is a baked film precursor because of its chemical composition , not because I say so , but because the
elements are there compounded which exposed to heat
will decompose from there to the same end product
as will other precursors having the same elements ,
but arranged slightly differently . It's like how much difference in sweetening your coffee is gotten from
using sugar cubed or granular , if after it dissolves ,
it makes no difference in the end . In some situations
it is just that a different form for the material starting out ,
is more convenient to handle , even though it ends up being the same thing later when the heat hits it .

This kind of layer chemistry is thin film chemistry and is
semiconductor technology also . The substrate and spinel interface is a bona fide thin film "MOS device" of Schottky
titanium substrate architecture , " Zenerized " by special doping into having a zener voltage probably in the hundredths of a volt region . That's probably what has Twospoons all stirred up , he probably smells a production run of a new variant Schottky diode here ....never mind the perchlorate anode coating that can be wrapped around it

[Edited on 13-12-2007 by Rosco Bodine]

Quote:

Originally posted by Xenoid Glad someone's working around here... Meet Gertrude, my latest anode. She's blue/black, smooth, very shiny and hard! Gertrude has a double layer Co-spinel INTERFACE and 8 layers of beta-MnO2 on top!

Hope springs eternal

Geez, Rosco, give me a chance! I finally decided to make the Mn nitrate from carbonate and nitric acid because I'm having trouble processing the stuff from the sulphate route.

Sorry, it's just plain old garden variety MnO2. If it looks like holding together I'll try doping it next...