cheap do it yourself DIY solar cells from alufoil

[Mark69]

@Triffid,

try one of these patent numbers:
5928438
5726065

Hope that helps,
Mark

[FreeEnergy]

http://www.google.com/patents?q=5928438

http://www.google.com/patents?q=5726065

[hartiberlin]

I tried yeasterday to build an
alufoil solar cell on the basis of a Graetzel cell.

I tried it this way.

I scratched the alufoil with sandpaper a bit,
but my alufoil was too thin, so I used directly
the alufoil from the box , so there is always a
small Aluminiumoxid layer on it.


Then I put ( dissolved) Titandioxid TiO2 into IsoPropylalcohol 98 %
and smeared it in a very thin layer onto the alufoil.
Then I heated up the Alufoil on
the plate of my electro kitchen stove
to get some of the TiO2 into the Al2O3 oxid and
build a PN layer...

Then I use a hibiscus tea in destilled water mixed with table salt solution as the electrolyte onto it
and sprayed that hibiscus tea -tablesalt-solution onto the alufoil with the
Titandioxid.

Then I used some graphite brush to have contact
with the
hibiscus tea table salt solution and
measured the voltage between
the alufoil and the graphite brush.

It was around 0.7 Volts
but there was no light sensivity of this cell.
It was a pure galvanic effect.

So basically I just built only a galvanic battery cell.

Hmm, I have to find out, how I really can build
a PN junction layer with Alufoil and other materials
or I really have to go with a
mix of Indium-TinOxid on glas and TiO2 as the PN-Layer.

The real secret of the Graetzel cell is purely where exactly
the PN- junction is located and I guess it is the very thin layer of
the conducting Indium-Tin-Oxid bounded to the TiO2 layer.

This InZnOxid and TiO2 forms the PN junction which is
sensitive for the light and the Jodid electrolyte is only
for the current conduction and can also be replaced by other
electrolytes..

Okay, so how do I now make my own cheap
conducting Indium-Tin-Oxid glas plates ?

Or does anybody have an idea to still use the Alufoil
for the backplate of a solar cell ?

Many thanks.

Regards, Stefan.

[triffid]

I went ahead and made hard copies of patents 5928438 and 5726065.I will take them home tonight and see if I have a match with the info I already have.As far as I understand the process the aluminum foil is on the bottom and acts as the pos electrode.Then something is put on the foil,allowed to dry then baked at 600 degrees F for 3 to 5 minutes.Once cooled down something else is put on top ,allowed to dry ,then baked at 600 degrees F for 3 to 5 minutes.Then last a metal paste is placed on top  and allowed to dry,but no baking! This top layer then acts as the neg electrode of the cell.An outdoor grill is mentioned in the article as a good way to achieve these temps.Thanks to those of you who helped with the numbers.Triffid

[triffid]

I should add that that last layer(metal paste) is put down in a screen pattern,not as a solid layer.Triffid