Homemade graphite rod fuel cell

[hartiberlin]

Here is a video, which shows at the end,
how 2 graphite rods can be used to generate about 2 Volts from
stored H2 and O2 gas inside of them by using electrolysis before.

http://www.youtube.com/watch?v=mibnOhczXEk

What I don?tyet understand, if indeed the stored gases are used up
or if they use up stored Ions like OH- and H+ ions.

Can a chemist have a look at it and tell us please ?

This might just be the same process that is going on in a super capacitor.

Regards, Stefan.

[ResinRat2]

Unfortunately, I can't access youtube at work (I wonder why?) but do you think this little link may give a good example of what is going on? It uses two graphite electrodes.

http://www.bthc.edu.hk/~hchsu/chem_hp/chemanim/electrolysis/electrolysis.html

Let it load, then hit the play button. Gives the chemistry examples.

[hartiberlin]

Okay, as I have already guessed, it can only be the H+ and OH-
ions, that still sit in the graphite crystal unrecombined, which are
charging up the graphite after the elecrolysis process.

That is no wonder, that nothing happened, when I tried to bring a graphite rod
into  H2 gas enriched  water and the other graphite rod into O2 enriched water,
that there did nothing happen.

We have to get the OH- and the H+ ions directly into the crystal matrix of the graphite
to get a fuel cell with voltage output.

In professional fuel cell this is done with plating graphite with a costly
platin catalysator.

So I wonder, what exactly the platin will do at the graphite ?

Will it split the H2 gas into H+ ions  at one graphite electrode
and at the other electrode will it split the O2 into OH- ions ?

We have a find a better and cheaper way to do this.

Maybe one could use just silver metal  atoms too and suck them
up into the graphite lattice ?

You can easily use a collaidal silver generator electrolyizer to
generate lots of very small silver atoms, that can be embedded
into the graphite lattice...

I will try this out next time I am at home and have some free time.

If somebody could still post a list of metal atoms or other materials, that act
still better than platinum or silver to split H2 and O2 gases into their
ions, I would be very grateful.


Many thanks.

Regards, Stefan.

[ResinRat2]

Hi Stefan,

I know this subject is a bit dated, but I found a website that listed solubility of gases in water:

http://www.engineeringtoolbox.com/gases-solubility-water-d_1148.html

One of the gases listed was hydrogen. It gives a solubility of 0.0015g. of Hydrogen / liter of water at 25C.

This means that in one liter of water there are:(22400ml) X (0.0015moles H₂) = 33.6 ml of hydrogen in a liter of water at 25C.
                                                                  (mole H₂)

So if this hydrogen saturated water would be run through one of my hydrogen/air fuel cells it should give off a voltage (I think)

This would be an interesting experiment to try. I will boil a given amount of water for several minutes to drive out any dissolved gases, then bubble my excess hydrogen through the water as it slowly cools to room temperature. Then I will run the hydrogen saturated water through one of my fuel cells and see if I get a voltage reading. This would be VERY interesting, and a much safer way to store hydrogen.

I also wonder if a very thin layer of this water was placed in a dish, if it would actually ignite with a flame?

Of course I need to get my reactor going first. This should be in about a week.

[ResinRat2]

I made an error. A mole of H₂ gas weighs 2 grams not one gram. So the volume of gas dissolved in water is cut in half to approximately 16.8 ml of hydrogen gas per liter of water.

Sorry about that.