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Xenoid
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| Quote: | Originally posted by jpsmith123
Here's one of the procedures I took from one of the patents; unfortunately I've forgotten which one. I will look and see if I can find others.
Example XVI
Two titanium rods were degreased and pickled and subsequently placed in a galvanic bath having the following composition:
100 cc. ethanol
100 cc. water
1 g. ruthenium chloride
10 g titanium chloride
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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]
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Rosco Bodine
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That sort of scheme using Ru doped *thick layer* TiO2 is a solid solution scheme which works well because Ru has unusal solubility in TiO2 and
penetrates it readily , more easily than anything else actually .
I really believe that the *thin layer* TiO2 interface schemes that are workable using Co or Mn instead of Ru
are not going to work interchangeably in that sort of scheme , and TiCl4 isn't common either .
I have been thinking more about the"modifier oxide" concept which is involved there , and what it really seems to be trying to accomplish is a
thickening and faster building of the coatings while maintaining good electrical conductivity and chemical resistance for the
thicker outer layers .
Something similar I have been thinking about with interest
is a possible parallel "doped nascent oxide derived from hydrolysis scheme" , It involves the hundred year old experiment which showed a persistent
hydro-gel complex formation occurs for stannic nitrate with other metal nitrates in small proportion which decompose to an M2O3 form , iron being the
nitrate reported as being studied most , but if nickel works as well it could be interesting .
Baking such materials should result in decomposition
to a doped tin oxide , but the conductive properties are unknown . This decomposition could also proceed anaerobically and in conjunction with
Co(NO3)2 .
What I am trying to accomplish here is a combining
of the good conductivity interface derived from the
baking of a nitrate , which seems more promising
than other precursors for thicker layers particularly ,
since the nitrates decompose already in the higher
oxidation state and don't require atmospheric oxygen ,
along with the sealing effect of a tin oxide component
which seems to be a very good amorphous film forming
material , which will be the hot melted "glue" in the baked mixture .
One problem with the chlorides precursors like dann2
has been investigating , is the oxygen required for SnO2
to form , has to come from somewhere external to the
precursor itself , for example it has to rip any water present apart for its oxygen and get even more from the air to complete the formation of SnO2 .
But using a
nitrate , the required oxygen and then some is self- contained in the precursor which decomposes directly
as the SnO2 , and also there is some nascent nitrogen
provided there which may even have a possible nitriding
effect where it may permeate downward or elsewhere
to encounter any free metal component . So anyway , it just seems in the nature of the mixtures involving precursors as nitrates , that they are
higher intermediates for the desired end products of baking to decomposition .
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chloric1
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How does one make or obtain "tin nitrate"? Is it is it's stannous or stannic form? It has been previously stated this compound hydrolysises easily.
Is it merely precipitating stannic acid and redissolving in strong nitric acid?
Fellow molecular manipulator
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Rosco Bodine
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Yeah that's what I have been able to find in some very old texts . It is called stannic nitrate which would be I presume
Sn(NO3)4 , but it probably undergoes some spontaneous hydrolysis to a basic nitrate of lower oxygen content , on
evaporation of solution . I'll go back and get some links
from the google books archives for pertinent information .
The curious thing is the way the stannic nitrate interacts
with other polyvalent metal nitrates to form complexes
which virtually defy separation , and I suspect these are
members of the MMO molecular compound or perhaps
coordination compound groups .
Molybdenum also forms a nitrate , and its polyvalent properties would seem to commend it as a candidate
for a dopant in combination with just about any other
metal oxide , possibly with SnO2 , and already reported
as a bimetal spinel with Co .
I am still thinking that differing chemistry baked layers in sequence , which are inclined to react with the layer before , are worth experimenting .
There's the possibility
also there of creating a "bi-electrode" barrier effect ,
should one of the layers be perforated in places , then exposing a slightly different composition layer which
could disrupt the chemical attack in the same way as
deliberately applied bi-electrode compositions do .
Here's a bit of some of the references , I'll have more
when I download and extract the specific pages .
Also there is US4576921 for a brief decription of dissolving tin in dilute nitric to get the stannous nitrate , which I think then decomposes to the
+II Sn oxide or hydrated oxide .
[Edited on 8-12-2007 by Rosco Bodine]
Attachment: Tin nitrate related Gmelin.pdf (187kB)
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Xenoid
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What happened to jpsmith123, has he gone walk-about again?
Update: The cobalt oxide anode in the chlorate cell is still running, the electrical parameters are rock steady after 2 days (48 hours). The black
coat is still completely intact. This is the one with 4 coats of 50% solution.
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jpsmith123
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It's actually my fault Xenoid as I wasn't very clear.
In one of Beer's patents, I think #3632498, he describes in general terms the methods that may be used to deposit mixed oxide coatings. One of those
methods he describes is electrolysis, using AC, where the electrolyte is a solution of mixed salts whose metal oxides are to be deposited.
The example I gave is the one given in that patent. I don't know what the purpose of the alcohol is in that particular example, as he doesn't go into
detail.
In another patent his product mixed oxide is manganese dioxide and platinum oxide, and although he states that it can be deposited electrolytically,
his example uses thermodecomposable salts.
What I'm saying is that I think it would be worth trying AC electrolysis with cobalt and manganese salts in combination (and maybe even separately, as
we didn't try that yet, either).
I'm planning on doing it myself, but I have to gather up a variac and some manganese salts first, which may take me a week or two.
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Rosco Bodine
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tin nitrate hydrogel complex with M2O3 forming nitrate
Here's an interesting article from way back over a hundred years ago .
The chromium variant was also identified ,
and the nickel variant would seem possible , though
not mentioned , perhaps also molybdenum .
These compositions are doped sol-gels having
sufficient bound oxygen for their complete anaerobic decomposition on baking to a doped tin oxide .
[Edited on 8-12-2007 by Rosco Bodine]
Attachment: Tin nitrate M2O3 nitrate soluble complexes.pdf (430kB)
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Xenoid
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@ jpsmith123
I've got a variac and a transformer set up so I can go from 0 - 25 volts AC.
Why do I need 2 Ti electrodes, can't I just use SS and Ti?
I just did a quick check and put a solution of 10g Co sulphate in 100mls water + ~80mls of alcohol in a 200 ml beaker. I put in a SS electrode and
small strip of etched Ti. With this setup, to obtain 1.5mA/cm^2 (15A/m^2) only requires a voltage of about .5 volts. To use 13 volts I would need to
have the electrodes about "a foot" apart. Maybe the alcohol is to increase the resistance of the solution, and one needs to develop a high voltage
across the cell. Anyway I left it for 1 hour and nothing much seemed to happen, I put it in a NaCl solution but it passivated straight away!
With these type of electrolysis/plating exercises does one need to control the electrode spacing, such that certain voltages are (not)exceeded. I've
always just made up a cell, dialed up an appropriate current and not worried about what the voltage was. Am I being a little naive in this respect?
The voltages of cells have always confused me!
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Rosco Bodine
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Voltage is going to depend upon electrode spacing
and the conductivity of the electrolyte so it varies
with conditons . The current density is what you
can use as a definitive value for the energy flux
at the electrode surface .
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jpsmith123
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I'm thinking that Beer uses two pieces of Ti because the solution will plate out oxide on both electrodes?
As far as the alcohol increasing the resistance...I had the exact same thought. I think that's a very reasonable assumption.
Did you get an oxide coating on the Ti from the AC?
And yes I go by current density too...to me the voltage is primarily a "trouble indicator" of sorts.
BTW did you look at the paper "A New Cobalt Oxide Electrodeposit Bath..."? If you have some Co Sulfate and Nitrate and Boric Acid you could try that
method of cathodic electrodeposition (it sounds like the Co Chloride is nice but not necessary). I think that method may be breaking some new ground.
I've never seen any patent talk about cathodic electrodeposition WRT anode coatings, and the papers claim it's highly adherent, which our anodic
coatings certainly were not.
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dann2
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Hello,
The voltage quoted in theses types of set up's is always quoted with reference to a third electrode in the set up, usually a, SCE, Saturated Calomel
Electrode (Calomel is a compound of Mercury (Chloride?).
They do not mean much of anything to us IMHO except that if a paper gives a voltage that is higher than another voltage then with your set up you
would be higher too (if ya know what I mean). The actual voltages will not be 'convertable' to a value that will make sence with your particular set
up. Clear as mud.
Go with current density as Rosco said.
Dann2
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Xenoid
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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!
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Rosco Bodine
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Here's another idea .
The chromium nitrate and tin nitrate hydrogel
could be interesting as an interface experiment
on Ti alloy 6Al-4V , because chromated aluminum is conductive , as well as is chromated TiO2 and "vanadated"
TiO2 , plus the SnO2 would act as a solid solution solvent and sealer overcoating that interface which should develop , with the SnO2 being
simultaneously doped by solid solution with the excess interface precursor oxides .
The materials in the alloy as well as in the interface precursors would seem to be a good match .
For a working , wearing coating , you could come back over the top with a lower baked MnO2 plus Co(NO3)2
plus Pb(NO3)2 mixture , which could make a complete
MMO anode in only two coat and bake steps .
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Xenoid
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| Quote: | Originally posted by Rosco Bodine
Voltage is going to depend upon electrode spacing
and the conductivity of the electrolyte so it varies
with conditons . The current density is what you
can use as a definitive value for the energy flux
at the electrode surface . |
@Rosco, I am a bit confused, in the "Perchlorate (not) with Graphite" thread, after my MnO2 coated gouging rods failed and I got what looked like
permanganate you made the following statement:
| Quote: |
Hmmm...I'm starting to wonder if your pink might actually be formation of *per*manganate ???? Maybe if you go above a certain voltage , it is like a
breaking point ??
You follow what I mean , you may be overdriving the anode and actually oxidizing the anode itself instead
of what you are trying to do the work on that is in the electrolyte .
It could be that the electrode gap being wide is causing you to use too much voltage to get good current ,
pushing the voltage up to a point that the potential is actually attacking the anode coating from underneath ,
at the carbon to MnO2 interface ? ...or at any rate
wherever it is occuring , maybe the overvoltage is what is killing the coating and you have to run the gap much closer to keep down the voltage much
lower .
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So if I coat a cobalt spinel anode with MnO2, how do I avoid permanganate forming, does it mean I have to adjust the geometry of the cell to get the
"right voltage" for a given current density. This is going to make cell design difficult!
It's sort of what I was harping on about a few posts back!
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Rosco Bodine
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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]
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Rosco Bodine
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Cobalt Spinel on TiH2 US4222842
@ Xenoid , and
@jpsmith123
You guys seem to be reading different significance about this
patent than what I am seeing . I look at this patent and
it sort of fits into both this thread and the other thread about TiH2 substrates .
The hydriding is evidently being used to accomplish a more
complete formation of the interface bimetal spinel .
The use of the titanium hydride powder or hydriding of a sintered substrate is intended to increase the thickness of the interface spinel as an
aggregate layer .
This is a higher art than the modifier oxides formed in situ
from simultaneous pyrolysis of precursor nitrates , but it also requires some uncommon materials and or techniques .
However the hydriding of a solid Ti substrate as a preparation for a baked Co spinel , is applicable to the
process using more common materials like the modifier oxides
of the Dow patents . I also posted this in the Ti substrate
thread because it involves both topics simultaneously .
Attachment: US4222842 Cobalt Spinel on Hydrided Titanium Substrate.pdf (141kB)
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jpsmith123
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Xenoid as I understand it one of the things you tried was anodic electrodeposition of MnO2 onto graphite. I'm wondering; (1) how well did it stick;
and, (2) what solution did you use to deposit it?
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Xenoid
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@ jpsmith123
I used Mn sulphate + H2SO4. I can't remember the details, (5mA/cm^2). I was expecting to get a nice smooth, shiny deposit, but I didn't see anything
at all. It may have formed a thin dull deposit, I didn't even test it. At that stage the solution was turning green ( from pale pink) and I gave up. I
find Mn solutions difficult to work with as they readily change oxidation state! I may not have had the right initial concentration or pH. It could be
worth revisiting, I didn't try very hard, and moved on to baking!
Edit: Oh yeah! I used a circular (tubular) SS cathode around the central graphite rod anode (genuine graphite - not gouging rod). I think I had gentle
magnetic stirring to stop bubble build up, maybe I heated it gently, probably not more than 40 - 50 oC. though, because it was just in a glass jar! -
Basically, nothing seemed to happen!
Note: Co spinel anode still running well, in chlorate cell.
[Edited on 9-12-2007 by Xenoid]
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jpsmith123
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Summary of Co Electrodeposition.
Here's what I think I've learned so far:
(1) Co Oxide cannot be anodically electrodeposited onto graphite, platinum or titanium from either a sulfate or acetate solution (although an oxide
seems to form, it just doesn't "stick").
(2) As per Xenoid, Co Oxide cannot be electrodeposited using AC (it doesn't seem to even form).
(3) A highly adherent Co metal coating can be cathodically electrodeposited onto Ti from either Co Sulfate or Acetate solution (but the Acetate
solution gives a much smoother, nicer looking coating).
(4) Titanium can be cathodically electrocleaned/degreased, and, depending on current density and time, hydrided (I've done it in NaOH, Na2CO3, H2C2O4
and HC2H3O2).
Here's what I don't know:
(1) Can Co Oxide be cathodically electrodeposited onto Ti or graphite using the formulas specified in the two papers we've recently gotten (the papers
claim a highly adherent coating)?
(2) Can mixed Mn and Co Oxides be anodically or cathodically electrodeposited from, say, their mixed sulfate solutions (I've read where MnO2
anodically electrodeposited from sulfate solution is supposed to "stick" very well, so maybe it's worth a try)?
(3) Is it possible to somehow oxidize the Co metal layer that can be cathodically electrodeposited?
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Rosco Bodine
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| Quote: | Originally posted by jpsmith123
Here's what I think I've learned so far:
(1) Co Oxide cannot be anodically electrodeposited onto graphite, platinum or titanium from either a sulfate or acetate solution (although an oxide
seems to form, it just doesn't "stick"). |
It is possible that your deposition rate is too high , pH is wrong , and concentration of the precursor is too high .
There is a window condition for just about every electrolysis
scheme including electrodepositions where the desired result may be obtained , and any variance outside that narrow window trashes the intended result
and produces something else . The oxidative cold soak depositions could be a model for the conditions required for Co spinel , as
the soluble cobalt should respond similarly in the same bath
to an electrolytically driven oxidation , as it does to a chemically driven "electroless" oxidation . A variation on the method combining the
electroless with the electrolytic methods could even be operable . I think you are premature in the observation that it can't be done , but probably
right in saying it isn't so easy .
| Quote: |
(2) As per Xenoid, Co Oxide cannot be electrodeposited using AC (it doesn't seem to even form).
(3) A highly adherent Co metal coating can be cathodically electrodeposited onto Ti from either Co Sulfate or Acetate solution (but the Acetate
solution gives a much smoother, nicer looking coating). |
Yeah but the possibility of interest here involves the minimal sort of flash plating which does not give a continuous layer , but minimally spot
plates the metal onto regions , which then become deposition nuclei when the current is reversed .
| Quote: |
(4) Titanium can be cathodically electrocleaned/degreased, and, depending on current density and time, hydrided (I've done it in NaOH, Na2CO3, H2C2O4
and HC2H3O2). |
Yeah but the etching with HCl or oxalic followed by hydriding in 5% H2SO4 is better documented for operative use .
| Quote: |
Here's what I don't know:
(1) Can Co Oxide be cathodically electrodeposited onto Ti or graphite using the formulas specified in the two papers we've recently gotten (the papers
claim a highly adherent coating)? |
Haven't yet carefully studied and digested those last papers . Possibly
this is a variation on the oxidative cold soak process , where a very low cathodic potential is used which is insufficient for the plating out of the
metal , but the oxidation potential is high enough on the anode that the entire electrolyte is being oxidized , similarly
as if a bromate had been added , and then the less soluble
higher oxidation state Co oxide is plating out , preferentially
adhering to the cathode due to electrostatic attraction .
This may be a case where the air oxidation is in effect making the anodic oxidation potential "bolstered" so its
"felt potential" to the electrolyte is higher than its actual electrical potential , allowing the sum of chemical and anodic effect to cause oxidation
of the lower valency Co to the higher valency and less soluble Co which then drops out of solution onto the target . Isn't this a hybrid electrolysis
/ electrophoresis scheme ?
| Quote: |
(2) Can mixed Mn and Co Oxides be anodically or cathodically electrodeposited from, say, their mixed sulfate solutions (I've read where MnO2
anodically electrodeposited from sulfate solution is supposed to "stick" very well, so maybe it's worth a try)? |
Sticking and a continuous vitrified solid solution are two different things with regards to permeability . To get the
needed barrier effect is likely going to require baking because
the diffusion does not occur sufficiently rapidly in thick sections at mild temperatures . It can do it on a nanocrystalline scale , but not on the
macro scale , where heating is needed to drive the process at a reasonable rate .
| Quote: |
(3) Is it possible to somehow oxidize the Co metal layer that can be cathodically electrodeposited? |
Yeah the surplus oxygen in a baked nitrates mixture could take care of that , if the metal layer was not too thick .
In some cases it might simply oxidize the metal when the
metal was made anodic , depending on the temperature
and pH , composition of the electrolyte , ect.
In the thread where Xenoid was trying to get MnO2 to bake onto graphite , the problem was adhesion , which seems to be the obstacle for most of the
schemes where you have materials which will work as anode coatings , but the real problem is getting them to stick and stay conductive with the
interface to the substrate . The schemes that involve conductive fillers as aggregates make sense , but many things can be used as those fillers .
Nanocrystalline spinels have been made via chemical means at mild temperatures as conductive pigments for inkjet inks , and these could be useful as
fillers for building thicker anode coatings , using
tin oxide or other oxides as the carrier and hot melt glue
for bonding during baking . I am pretty sure that MnO2
and I am positive that magnetite have been produced as
inkjet pigments , and there are probably others . These
materials could serve the same function as other particulate
conductive bronzing powders which are used as an aggregate bonded by spinel or by solid solution SnO2 .
I recently posted that the Co spinel could be made in nanocrystalline octahedral form by a separate baking in a crucible of IIRC a mixture of the
oxalate and the chloride .
Possibly these crystals would be cemented into a layer
if mixed with Co nitrate alone and baked , or if mixed
with a Co plus Zinc or nickel precursor nitrates mixture ,
which would react with the preformed monometal cobalt spinel by diffusion on baking . Diffusion layers are what I
presume is the mechanism for bonding in most of these
materials and it should work in this case as well .
The whole mechanism of DTO solid solution barrier or interface laters depends on the dispersion of oxides
and their diffusion is involved also for bonding with whatever
substrate or aggregate . The Corning patent US2564707
gives an extensive list of ATO mixtures having a third oxide added . The patent studies mixtures derived from chlorides
which were flash decomposed and oxidized by air following
spray deposition onto hot glass surfaces . The properties
of similar end chemistry coatings derived from different precursors such as nitrates and decomposed more slowly
by baking , should closely parallel the data from the Corning
patent . For thicker baked coatings the nitrates are likely
better precursors anyway , since more or even all of the required oxygen is present in the precursor . Ideally perhaps
an even "oxygen balanced precursor mixture" could be formulated to optimize the quality of these baked coatings .
[Edited on 9-12-2007 by Rosco Bodine]
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Xenoid
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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.
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jpsmith123
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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.
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Rosco Bodine
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Yeah there is a similar Co-Mn spinel composition which has been or is still being investigated as a anode material
in lithium batteries . There's an article listed for that
from Science Direct and I'll get the DOI # for it if you like .
I still think for perchlorate anodes , baking is going to be required at least for the near or at interface layers , because of porosity . Even the
baked coatings have some porosity , but it is way less than plated coatings . No reason why a first plated coating couldn't be later baked also to
get past that porosity , if it would sinter on heating . Somehow though there may be a formation mechanism involved with the thermal decomposition
which kicks the reaction via some sort of lattice collapse
which can't occur in the case of plated on coatings ,
so they may never be equivalent materials physically ,
even though the end chemical composition is the same .
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jpsmith123
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Does the study you're thinking of involve electrodeposition? If so, yes, I'd like to get the DOI#. On second thought, it may have useful information
regardless the deposition method. Thanks.
As far as baking goes, I'm actually thinking about trying to do it in a microwave oven. IIRC, cobalt oxides are very good microwave susceptors. If a
coating could be put on by electrodeposition, maybe it could then go in the microwave and be heated very hot, in a hurry.
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Xenoid
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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]
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