IntroductionDye Solar Cells• Low cost thin film solar cells• Invented by Michael Grätzel in 1991• Mechanically robust and can be made on flexible sheets• Commercialization just started with three major companies: DyeSol, Austraila; Solaronix, France; ECIC, Taiwan.
Advantages:• Works well under diffused sunlight, less sensitive to angle of incidence.• Can be made fully transparent, can have a lot of aesthetic applications.• Bifacial, absorbs light from both faces, can be inverted.• Manufacturing costs much cheaper than the commercially available PV silicon cells.• Also works at high temperature, owing to the thin conducting film that radiates internal heat.
Materials & Methods:DSC’s four major components:1. Conducting glass2. TiO2 layer3. Dye4. Electrolyte5. Counter electrode
Building of DSC:Conducting glass:• Commercially available as ITO (Indium Tin oxide glass) used normally in LCD screens.• Glass with a resistance of at least 30Ω/sq.cm is required.• Glass has to be highly transparent.• A normal 160 * 80 mm ITO glass (4mm thick) costs around $150 (Courtesy: Dyesol Inc.)
Lab preparation of conducting glass •Stannic Chloride is obtained and dissolved in ethanol(40% w/w) solution – (5 gm in 5ml of methanol) •It is sprayed upon the glass surface with the help of a mister. •The glass is then kept in the muffle furnace and is heated up to 400-500 ° C for about 15-20 min •Sn4+ gets reduced to Sn2+, forming a mix layer of SnO2 & SnO4, which are responsible for conductivity
Conducting glass by Thermal Evaporation @IPR, Gandhinagar
ResultsConducting glass Analysis• SEM Analysis
• XRD Analysis Intensity/ cps 2 Theta/ (Scan axis: 2:1 sym.) XRD pattern reveal that films contain SnO and SnO2 both phases with SnO peaks with higher intesities and preferred orientaions.
Transmission Spectra Transm ission Spectra for SnO2 film s deposited by therm al evaporation and Plasm a assisted thermal evaporation 1 250 C 0.8 Transmittance 300 C 0.6 0.4 250 C with RF 0.2 300 C with RF 0 350 415 480 545 610 675 740 805 870 935 1000 Wavelength(nm )Transmission spectra of films show that as the substratetemperature increases transparency of the films increases. Alsospectra of plasma assisted films are lying somewhat above thespectra of thermally grownFilms.
Open Circuit VoltageS. No. Resistivity of Conducting Illumination Voltage(m glass (W/m2) V)1. 89.59 Ω cm 120 (Sun light) 9892. 129.8 Ω cm 120 (Sun light) 6923. 127 Ω cm 120 (Sun light) 4684. 146 Ω cm 250 (Solar Lamp) 19
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