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how do i make lead dioxide electrodes? Answered

hello, i want to try and make some lead dioxide electrodes, but i have no clue as to how.

i need to make lead dioxide, then apparently mix it with a binding agent to make an electrode, and thats all the info i could find

could someone please fill me in on the rest?

like what that binding agent is and so on, what is the proccess involved in turning lead into lead dioxide?

i have some old car batteries due to go to the dump as they are working at less that 50% efficiency which was apparently enough reason for my dad to say theyre ready for the dump!

is it true that the lead sheets inside the batteries are just pure lead dioxide?

the reason i need it is to make sodium chlorate, and in extension, potassium chlorate, and i dont want to use graphite electrodes as they will errode away, plus i cant afford any platinum electrodes, nor can i find them for that matter!



Best Answer 7 years ago

You start with lead, and produce the oxide-coating on the lead via electrolysis.


thankyou lemonie,

do you know though if the lead plates in old car batteries though, could be used directly, as an electrode? or would i need to electroplate some other kind of electrode?

Yes and no. If you use them directly, they will fall apart because the substrate will dissolve. You can make pure lead carbonate from them however that can be converted into lead acetate or lead nitrate. This is a multi step process but uses only easily obtained supplies (can you say thank you Wal*Mart and Home Depot?)

1) convert the lead sulfate to lead carbonate by soaking the plates in washing or baking soda solution. This takes a long time. (you can do this with both kinds of plates)

2) convert lead carbonate and lead dioxide to lead chloride by soaking the thoroughly rinsed plates from step 1) in HCl. Heat makes this reaction faster. Lead will also dissolve in HCl but much slower so no need to separate the plate types. When using heat. continue heating until the fizzing stops, do not boil. Add more water (or recycled solutions) as necessary.

3) filter out the hot solution with coffee filters. Recycle the gray sludge back into the HCl solution in step 2). If your pH is too low, the coffee filters will dissolve. If that happens, you didn't wait long enough or you added too much HCl.

4) cool to form lead chloride crystals. Most contamination stays in solution which can be returned to step 2) also. But you risk a concentrated solution of contamination. You can add soda and return the contaminated white precipitate to step 2) instead.

5) rinse the crystals in cold distilled water to remove more contamination. (return the rinse water to step 2). Again, you can add soda and return the contaminated precipitate only.)

6) dissolve the crystals in hot distilled water.

7) slowly add to cold washing/baking soda solution. Heat will cause the CO2 to come off as a gas if done too quickly. Baking soda will do this anyway.

8) white lead carbonate will precipitate. Stop adding when no more precipitate forms. Add more soda to precipitate the last of the lead carbonate.

9) filter out the lead carbonate. The clear solution should be fairly free of lead. Don't recycle the solution in this process to prevent sodium buildup but you may be able to use them elsewhere.

10) rinse in distilled water. The rinse water will be fairly free of lead. Don't recycle the solution in this process to prevent sodium buildup but you may be able to use them elsewhere.

11) lead carbonate can be dissolved in nitric acid or distilled vinegar for electroplating lead dioxide.

the easiest way I found was:
get 100 grams of water soluable lead (lead nitrate, or lead acetate)
get 60 grams of water soluable copper (copper nitrate, copper acetate, not chloride PbCl is insoluable in water)

mix chemicals with distilled water and 2 drops of dish soap (surfactant, it makes a smooth coating)
mix until fully dissolved
with a amperage limited power supply attach your graphite electrode to the positive and a piece of copper to the negative.
the copper ions take less voltage to reduce therefore they get priority to the cathode forcing the lead ions to the anode where they are oxidized to lead dioxide (solid)

you should limit the amperage to as low as possible 2ma per square cm worked well for me. rotate the electrode 90 degrees every 15 minutes for 2 hours minumim. (after 2 hours I had 10 grams of PbO2 deposited on my graphite electrode.
good things come to those who wait

i have a question... why would you need copper for this?? i can easily get / make Pb(NO3)2 and i have already CuSO4 which i guess would work for this.. but what would the CuSO4 help in this process??

well, allot of the nitric acid forming from the decomposition of nitrate molecules, will immediately decompose into nitric oxides when it comes into contact with metalic lead forming at the cathode. wasted nitrates form nitric oxides and bubble out.

I dont recall the exact math, but by adding copper, the copper will plate the cathode forcing all lead to the anode, simple chemistry that is, anyway. by preventing any lead from forming metalic lead, all of it has the potential to oxidize into oxide. this means that all lead nitrate can be used, while without copper, only half the original lead nitrate can be used.
This however excludes nitrates lost by adding copper and lead oxides, carbonates and ect to form more lead dioxide and soluble copper, eventually, as copper also causes the nitric acid to decompose when it reacts, the nitric acid formed will eventually decompose into oxide and bubble away, however in this process, more lead is oxidized than without copper.

if i use both lead and copper nitrate, will that mean i get nitric acid?
if so, thats a double bonus for me yay!

also, is it completely necessary to use copper nitrate as well?
will this reaction still work with just lead nitrate?

the copper nitrate gets priority to the cathode if it is not there then the lead metal, not dioxide, will go on the cathode. I do not believe you will have nitric acid afterward I believe they will just be nitrate ions, and hopefully not released as nitrogen dioxide (corrosive, toxic. it turns to nitric acid when put through a liquid oxidizer like hydrogen peroxide.)

to sum up you need both. the acetate chemicals are easy to make 50% vinegar (CH3COOH), 50% hydrogen peroxide (H2O2). heat them up then add metal (nickel doesn't work, unfortunately) copper and lead both work (with lead do not heat the solution very much if its too hot is oxidizes very quickly into lead dioxide solid being absolutely useless to your goal.

the formula goes as such for making lead acetate:
2Pb (s) + H2O2 => PbO (s) + H2O
PbO (s) + 2 CH3COOH (aq) +> Pb(CH3COO)2 + H2O

I hope this helps explain things

at the moment , i have a dissasembled sealed lead acid battery that uses cotton or similar, between each plate.
ive tried electrolysis on a single cell, but it doesnt work,

the battery has been long since dead.

there are twotypes of plates, one grey, i suspect it is lead,
the other is very fragile, dark brown and reddish,
is this by chance lead sulfate?
is there any way to convert this into sulfuric acid, so i can convert all the lead into lead dioxide by electrolysis?
if through electrolysis, what should the current and voltage be? as ive tried electrolysis with many battery chargers (on the removed cut plates) , but they seem to stop working after 5 minutes of bubbling. why is that?

Have you seen that NurdRage video on the preparation of a mixed-metal-oxide coated titanium electrode? Uum... here:

According to the video, that electrode was specifically intended for use in the corrosive environment of a potassium chlorate producing cell.

yeah, but i have no access to any cobalt nitrate, or manganese nitrate aside from reacting them with nitric acid, but still, i have no access to cobalt to react, plus
i want to use lead dioxide which i have access to.

You know that's a good point. All that stuff (the Ti metal, Co and Mn salts, nitric acid) is somewhat hard to find compared to metallic lead. Another plus for Pb is that it has a low melting point. So it should be possible to make some Pb electrodes in whatever shape you want. I have melted lead before using a steel soup can for the crucible, and a propane torch for the heat source. I still have not figured out the best mold material to cast lead into. Sand? Clay? Anyway, I think Lemonie's got the BA for this one. And good luck with your electrode building efforts.