Utilization of the crude extract of Akapulko ( Cassia alata Lin.) leaves for potential application in dye-sensitized solar cells (DSSCs)/ Gemini Magana, Bryan Lee Morcilla, and Erah Mae M. Sarmiento .--

Thesis (undergraduate)

College of Science .-- Bachelor of Applied Science in Laboratory Technology: Technological University of the Philippines, 2024.

Includes bibliography

This study presents the potential of the crude extract of Akapulko (Cassia alata Linn.), as a
sensitizer in dye-sensitized solar cells (DSSCs). It also investigated the different groups of
compounds in the crude and included an application of utilizing the extract to light up a 1.1V 0.3A
light bulb. Constant weighing was done to calculate moisture content of the leaves which resulted
as 70.74%. The crude extract was then obtained using maceration extraction of the plant using
80% Ethanol, filtered and isolated using a water bath. The extraction yield was calculated to be
11.69%. The extract then underwent phytochemical tests and tested positive for Alkaloids,
Anthraquinones, Flavonoids, Phenols, Saponins, Sterols, Tannins, Quinones. The extract was then
subjected to a viscometer which resulted in its viscosity of 14.4 cP. To obtain the spectrum of light
that the extract absorbs, a UV-Vis analysis was done. It showed many peaks, by virtue of it being
crude, and a broad spectrum of absorbance from both visible and UV regions of light. After the
characterization tests were done, the extract was subject to the application of using it as a sensitizer
for dye-sensitized solar cells. An initial test of the voltage output of different DSSCs with differing
variation of its quantity in the cell resulted in the variation 1.5 g of crude extract with 0.5 g of
titanium dioxide as the one with the highest average voltage output. This average voltage output
was compared to the voltage output given by a synthetic dye namely Eosin-Y. A percentage
difference of 21.878% was found. Lastly, the performance parameters of 7 Dye-Sensitized Solar
Cells in series connection with the bulb were taken note of. It was found that the cells exhibited
minimal voltage and current outputs, which increased over time as the temperature rose and the
DSSCs gathered lighter. It was found that by the 2 hour and 43-minute mark of being exposed to
light, the bulb first lit up.
Keywords: Dye-Sensitized Solar Cells (DSSCs), Series Connection, Sensitizer, Voltage Output,
Bulb