Transcript how to make a solar cell

Dye Solar Cell Assembly
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Glass handling
Titania deposition
Sintering process
Sensitizer impregnation
Platinum deposition
Sealing electrodes
Electrolyte filling
Completing the cell
Materials
Materials
Materials
Materials
Materials
Materials
Materials
Glass handling
• Transparent conducting oxide glass (TCO glass)
should not be touched with bare fingers. If
fingerprints or other contamination are
present, clean with ethanol and dry with a
hair-dryer.
Glass handling
Glass handling
Glass handling
ZNO solution deposition
• Stir well the ZNO pastes before use, not shake
unless bubbles could be formed.
• The thickness of the adhesive tape will
determine the thickness of the titanium
dioxide deposited on the glass. We use
"Scotch Magic" tape from 3M, having a
thickness of ~50 µm. This tape can be easily
removed from the glass without leaving traces
of adhesive materials.
Sintering process
• The sintering process allows the ZNO
nanocrystals to "melt" partially together, in
order to ensure electrical contact and
mechanical adhesion on the glass.
• Heat electrode to ca. 450 °C for about half an
hour.
Platinum deposition
• The platinum catalyst is obtained by using the
Pt-Catalyst T/SP product which can either be
squeegee printed or screen-printed using a
polyester mesh of 90. Dry at 100 °C for 10 min
prior firing at 400 °C for 30 min.
Cleaning electrodes
• Working electrode (ZNO impregnated with
Ruthenium 535 sensitizer): Rinse with
absolute ethanol and dry with hair-dryer.
• Note: Never use water or water based
cleaning solutions!
• Counter-electrode (TCO glass with platinum
catalyst):
• Rinse either with distilled water or use
ethanol and dry with hair-dryer.
Sealing electrodes
• Assemble cell as soon as the electrodes have
been prepared. Long storage of electrodes is
detrimental.
• If the cell is filled with Iodolyte TG-50, then
Amosil 4 is appropriate as a sealing material.
• If the cell is filled with Iodolyte AN-50 or Iodolyte
PN-50, then the hot-melt sheets SX 1170-25 (25
micron thickness) or SX 1170-60 (60 micron
thickness) should be used as sealing frame.
Electrolyte filling
• In cells having a sealing rim with two small
holes, the filling is done by putting a droplet
onto only one hole, and let it soak up.
Replenish droplet from time to time to avoid
dry-out and bubble formation.
• For long shaped cells, this process can take
about 10 minutes and maybe some small
bubbles are still left (these are not critical to
cell operation).
Completing the cell
• Wipe off excess electrolyte from filling ports.
Clean carefully the area around the filling
holes with acetone (usually electrolytes are
more soluble in acetone than in alcohol), so
that no traces are anymore visible. The
reflection of a light source shows pretty well if
the glass is clean or not.
Testing
• Prior testing, it is recommended to put silver paint
onto the contacts to ensure optimal electrical
connections and to minimize serial resistance losses,
especially when testing large cells.
• The typical output voltage of a dye solar cell should be
in the range of 0.6 to 0.7 V in full light (1000 W/m2).The
short-circuit current density should be between 8 and
12 mA/cm2 for a 8-10 mm thick fully impregnated
electrode, and the current should remain constant
under illumination.