Hello everyone in this video
I'm going to show you how I made a solar cell from very basic materials such as toothpaste
sweet cherry juice and tincture
Dye sensitized solar cell is a new type of flexible solar cells
Its inventor Michael Gray stirrer was awarded melindam technology prize for his invention
The first component needed for the production of such a solar cell is titanium dioxide
You can either buy it in a pure form or try to extract it from toothpaste
When going to the supermarket, I was specifically looking for good paste which contained titanium dioxide
It is any total space as a white pigment
besides this chemical can be found not only in toothpaste but also in die screams oatman's and other
cosmetics nevertheless
after buying such a toothpaste
I found out that besides titanium oxide there were lots of
Impurities so I decided to extract pure titanium dioxide
By rinsing it with 10% sodium hydroxide solution in 2-space
Colloidal silica is used as an abrasive in other words
It is very fine sand which can dissolve in alkali solution at high temperatures
I decided to make the solution with a whisk for milk after that
I decided to conduct the contagion having separated sediment which clearly contains titanium dioxide
However, upon further filtration very tiny titanium dioxide particles and the remnants of silicon dioxide
Collage the filter which made filtration practically impossible
So I had to quit doing that. I decided to end extracting titanium dioxide from toothpaste and
proceeded to using pure titanium dioxide
which I had bought earlier in order to be able to check whether or not this method of making solar cells is
effective besides titanium dioxide
You'll also need to get conductive glass
One side of it is sprayed with a fin of tin and indium oxide mixture
You can check on ductility of such a glass with a multimeter
Set the resistance mode by the way, you can use an old smartphone
sensor screen for that
The site card in oxide mixture will be resistant
Where is the other side won't lag when multimeter is applied to it?
Such glass is only expensive part of such a solar cell which cannot be made at home
of course in theory
I could have sprayed glass or plastic with a thin layer of metal for instance with silver
But I decided to make things easier and both this glass from Chinese Hortator
Now I need to make a paste from titanium dioxide which will solve as a semiconductor in such idea
Why solar cell to do that?
I'm mixing a small amount of titanium oxide with a diluted nitric acid solution instead of this solution
You can also use a 70% vinegar solution order for the pace to be more even at the first attempt
I made a very thick paste and later on
I regret that space should be sprayed on glass only after scotch tape has been stuck on in an outer fourth titanium dioxide
Layer to be the same thickness as the thickness of the scotch tape around once titanium
Dioxide has been spread
It is better to remove scotch tape while titanium dioxide
Paste is still moist because when it hardens as scotch tape is being removed it can break
That is why at the first attempt I ended up having such flaws and the second attempt
I managed to get more even shapes when paste has been spread of the glass
It is time for the most important stage
That is baking titanium dioxide film on the surface of the glass to make it harder
However, most manuals and articles I have read stays that it is enough to adjust
He is a film on a hot blade at high temperature besides there is no exact
Information about the temperature or time of baking that is why ahead it through trial and error
so to say as a first attempt a heated to glass on the hot plate at the maximum temperature of about
400 degrees Celsius for about 20 minutes it looked quite well
The next dish is so can bake titanium dioxide film in bright sweet cherry juice
Which contains natural dye and to silence in my case?
I used sweet cherry is juice is rich in natural dyes
I
squeezed juice out of sweet cherries poured it on the watch glass and deep the coated glass in tree five minutes into
Soaking I noticed that titanium film just got wet and even came off one piece of glass which is something no
Manual I read mentioned upon further reason of juice of the glass
I noticed that the oxide film completely came off
I had no choice but to start making paste again this time
I have heated coated glass on a hot blade oven an alcohol burner which according to the reading of the pyrometer
was heated up to
450 degrees Celsius no matter how diligently I tried titanium
Dioxide field would always come off upon submission into juice next time I decided to simply heat glass
over an alcohol burner
Thinking that maybe this time it will bake properly. However, the same thing happened over and over again
I even started wondering if I was saw the real
Titanium oxide or something different or maybe cherry juice was too acidic
Maybe temperature was too low or the film too thick
next time I decided to hit last over a powerful gas burner and hoped that
500 degrees Celsius for
30 minutes was enough for the oxide film after cooling off and so can induce the oxide layer
hardened enough 10 minutes into soaking the oxide film began change in color because
Anthocyanins molecules began sinking into the pores now. I am rinsing it with water and then
With pure alcohol in order for it to dry err
Finally I have at least one component needed for assembling a die
Synthesizes solar cell the next stage is preparing the other piece of glass
which will serve as an anode it needs to be coated in a layer of graphite or
Carbon which will be catalyst of the reaction
I'm just passing this piece of glass through a candle flame and I can see soot start forming on the surface
And the soot is pure carbon in the end
You need to make a sandwich consisting of the two pieces of glass
Placing them a bit off each other ages
Living space for attention electrodes and press them together with a binder clips the work properly
this DIY solar cell needs electrolyte containing iodine ions, and
Tincture of iodine you can buy at a Russian pharmacy and it will work perfectly fine
The thing is it is not only contains iodine dissolved in alcohol
But also water and potassium iodide thus increasing solubility of iodine in water
which is why it vaporizes worse from the solution after adding electrolyte and
Connecting electrodes to the solar cell and also to the multimeter in order to measure voltage
But I got totally confused at first
multimeters showed normal reading but when the titanium dioxide was read by light voltage will decrease
When I changed polarity I found out that it was a solar cell
it was just a battery which produced voltage even in the dark, which will increase
further upon adding of iDEN electrolyte I decided that it was enough for the first day of
Experimenting and decided to leave that until tomorrow
To do everything differently and take time to think about what was happening on next day
I made two more glass pieces coated in titanium dioxide
But that time I made the paste more liquid and also
Added liquid soap to eat in order to moist the glass better
I was heating the glass for - at about 500 degrees Celsius
Such an intense heat made titanium dioxide a bit yellowish. Does that happen?
Because this chemical has thermochromic property
This means that if titanium dioxide powder is heated to the high temperatures
It will turn a bit yellowish and if cooled down it turns white again
Zinc oxide for instance has the same property this time
I was soaked in oxide in raspberry juice for about five minutes after rinsing with water and alcohol
I assembled one more die synthesized solar cell from two pieces of glass
You need to be very careful when doing this they cause the carbon film of the second piece of glass is even more tender
Than titanium dioxide and it is not durable first
I decided to test the slightly damaged cell for activation
I filled it with an IDE an electrolyte just like the last time the whole thing
Didn't go to plan and for some reason it showed negative current in other words
It worked as a battery with a reversed polarities even through polarities were wired correctly
It is not worth Lea then when polarities of the multimeter were changed the cell responded only to wear a bright
Ultraviolet torch all of this seemed very strange to me
But then I froze that may be alcohol in the cells electrolyte triggers is catalytic oxidation. And that is why
polarities changed
Ideally to make this electrolyte
Ethylene glycol needs to be used as a solvent
Also the same thing happened to the other solar cell but in some time ethanol slowly began
evaporating and
wasted so in about 40 minutes
The cell more or less stable aside and it turned from a battery into a solar cell
Finally at least one fink world
when I pointed my torch my DIY solar cell showed 60 millivolt voltage and
40 micro ampere current of course this reading isn't serious
But this cell was made at home from scrap materials
Commercial die synthesized solar cells are usually thousands of times more efficient
So how do these cells work when light hits the surface of anthocyanin molecules?
which are attached to the titanium dioxide rate the dye molecules lose electrons which pass through
semiconducting titanium dioxide
Film live in holes these holes or spaces lacking electrons are occupied by the unpaired electrons
Which iodide ions have which are oxidized into tri iodide ions?
Which then diffuse through the car both film on the other electrode and then reduce again except in new electrons
This is how current travels inside a circuit after running all these experiments out of curiosity
I decided to substitute titanium dioxide with a regular toothpaste and just bake it on a current conductive glass
Wheel such a primitive solar cells work. I went through all the stages I had done before
Spread the paste and bake it for the 30 minutes over a burner as I was baking house
Organic materials were disappearing and I was left only with a layer of silicon dioxide and titanium dioxide
later to my surprise when I added raspberry juice the oxide layer didn't come off when I
Assembled the cell it also began working
Strangely and turned into a battery to about 50 minutes later
It also stabilized I'd and tada it to worked as well as other cell with pure titanium dioxide
It seemed to me that it performed even better
Apparently the small amount of titanium dioxide
The toothpaste contains is enough to make a semiconductor and move electrons
This was so due to the fact that titanium dioxide and silicon dioxide
Have a porous structure which prevents electrolyte from evaporating too quickly
In the sunlight voltage and current readings were a bit higher than in torchlight here
You can clearly see how the angle at which a light shines impacts efficiency of the solar cell
I think it will be great to run this experiment at schools and
Universities pupils will be able to make solar cell with their own hands without using expensive
equipment needed to produce silicon solar cells course at this point this type of solar cells cannot compete with
silicon for other solar cells based on non-organic
materials, however
Scientists are slowly
modernizing them for instance berry juice can be substituted with more efficient or atheneum complexes and
Expensive glass can be substituted with current conducting plastic and so on by the way
The solar service toothpaste remained working even 12 hours later
Maybe in the future so solar energy will become more affordable. Thanks to one of my subscribers
I'll be happy to see that happen