1. By: Monal Patel

2. Did you know that blackberry juice can be used to convert light energy into electrical energy? Dye-sensitized solar cells are photovoltaic cells that convert any visible light into electrical energy. The purpose of this experiment was to construct a dye-sensitized solar cell using blackberry juice and titanium dioxide to generate electricity. The dye- sensitized blackberry solar cell experiment was successful and the solar cell generated about an average of 48.0 mV (millivolt) of electricity. Abstract

3. The purpose of this experiment was to construct a dye-sensitized solar cell that will generate electricity using blackberry juice and titanium dioxide. Purpose

4. Dye-sensitized cells are used to convert light energy into electrical energy. Dye- sensitized cells are made up of thin film that uses TiO 2 as a semiconductor. The TiO 2 layer provides surface for the absorption of the dye (Teoli et al, 2015). Dye-sensitized solar cells have high efficiency and have been regarded as the next generation of solar cells because they can be produced at low costs (Chitumalla, R. K., Lim, M., Gao, X., & Jang. J, 2015). Introduction

5.  1 transparent indium tin oxide conductive glass slide (ITO slide)  1 TiO 2 coated indium tin oxide conductive glass slide  4 drops of Iodide electrolyte solution (0.5 M potassium iodide mixed with 0.05 M iodine in propylene glycol)  2 small binder clips  1 blackberry (thawed, frozen blackberries work well)  1 small spatula  1 graphite pencil  1 piece of parafilm  1 paper towel  1 razor blade  Multimeter  Light source (flashlight or sunlight) Materials

6. An indium tin oxide conductive glass slide (ITO slide) was coated with TiO 2 paste. Blackberry juice was used as a dye to coat the TiO 2 coated indium tin oxide conductive glass slide. The ITO slide was shaded using a graphite pencil in order to add a carbon layer. The parafilm was placed on top of the dye coated TiO 2 slide. Using a razor blade, the area of the parafilm on top of the TiO 2 slide was cut out then two drops of the iodide electrolyte sodium solution are placed on top of the TiO 2 slide. The ITO slide was placed on top of the TiO 2 slide so the conductive sides face each other then using a Multimeter, the voltage of the solar cell was measured. Methods

7. Dye-Sensitized Blackberry Solar Cell Photo taken by Monal Patel

8. Blackberry Solar Cell with Multimeter Photo taken by Monal Patel

9. Voltage of Solar Cell in mV (millivolt) Solar Cell 151.0 mV Solar Cell 245.0 mV Average48.0 mV Results

10. The dye-sensitized blackberry solar cell generated an average of 48.0 mV (millivolt) of electricity. Blackberries have an organic compound called anthocyanins. Anthocyanins are pigments, which give blackberries, raspberries, cherries, and strawberries its color (Teoli et al, 2015). Since anthocyanins have color, it can absorb light at the longest wavelength (Hosseinnezhad, M., Moradian, S., & Gharanjig, K., 2015). The carbon and hydroxyl groups in the anthocyanins bind to the TiO 2 causing the excitement of electrons (2015). Discussion

11.  Chitumalla, R. K., Lim, M., Gao, X., & Jang, J. (2015). Substituent effects on the croconate dyes in dye sensitized solar cell applications: a density functional theory study. Journal Of Molecular Modeling, 21(11), 297.  Hosseinnezhad, M., Moradian, S., & Gharanjig, K. (2015). Fruit extract dyes as photosensitizers in solar cells. Current Science (00113891), 109(5), 953-956  Teoli, F., Lucioli, S., Nota, P., Frattarelli, A., Matteocci, F., Di Carlo, A., Caboni, E., & Forni, C. (2015). Role of pH and pigment concentration for natural dye-sensitized solar cells treated with anthocyanin extracts of common fruits, Journal of Photochemistry and Photobiology A: Chemistry, 316, 24-30. References