| dc.description.abstract | Dye-sensitized solar cell (DSSC) or ‘Gratzel cell’ is a low-cost solar cell from the thin
film family which consists of TiO2 electrode coating, sensitizer from dye molecules soaked in the TiO2 film, a mediator electrolyte layer and a counter electrode. DSSC is designed to reduce cost from the usage of expensive material as in many conventional
solar panels. It is based on a semiconductor formed between a photo-sensitized anode
and an electrolyte that forms a photo-electrochemical system. The DSSC is first
founded by Michael Gratzel from 1988-1991 using synthetic dye sensitizers from
ruthenium based dyes. Fruits, leaves and flowers often display various colors in the
form of pigments that can be extracted and use as a dye in DSSC. Most green plants are
rich with chlorophyll and anthocyanin pigments which are important component that
gives colors to a plant or fruit. Anthocyanins are natural components that mostly give
red–purple coloration to fruits and plants, and they have wide light absorbance range
wavelengths. This thesis focuses on fabricating dye sensitized solar cell (DSSC) with
anatase and rutile-anatase mixture of titanium dioxide (TiO2) electrode at varied
thickness. The electrode is then sensitized with nature based dyes from fruits, plants and
flower and finally the investigation on an alternative counter electrode catalytic material
from carbon sources. It also revolves around electrical characterization of DSSCs based
on open circuit voltage; Voc, short circuit current; Isc, fill factor, FF, solar cell efficiency
(η), UV-Vis Absorbance spectra (nm), photon energy (eV), absorption coefficient (σ),
overall charge transfer (RCT), series resistance (RS), electron lifetime (τeff), and
recombination rate (Keff) and finally to propose an ideal nature based dye sensitized
solar cell (DSSC) based on optimum TiO2 nanoparticle crystalline material and
electrode film thickness, potential nature dyes and an alternative material as counter
electrode towards overall photoelectrical performance. Overall experiments have
successfully fabricate a cheap and nature based dye-sensitized solar cell. This thesis
proposes on the potentials of 10 μm thickness of rutile-anatase (RA) mixture based TiO2
nanocrystalline particle of 1 to 4 ratio concentration, absorbed into a high concentration
anthocyanin from keriang fruit extract purified to solution A and by the use of carbon
from battery (BG) as counter electrode with the thickness of 1.16 μm. The
implementation of this phase shows higher short circuit current of 6 mA/cm2 with fill
factor of 0.68 and an overall solar cell efficiency of 1.24 %. By implementation of this
phase, a reduction of overall charge transfer resistance to 130 Ω is observed. As for the
electron lifetime, a favorable result is as expected when its lifespan is longer (0.18 s)
than the recombination rate (5.49 s-1) which also shows that by the addition of graphite,
can suppress electron recombination to the dye or electrolyte. BG thickness of 1.16 μm
also provides better conducting pathway for the photo generated electron, thus
increasing the current and decreasing the resistance compare to the usage of Pt and other CE graphite thicknesses. The nature based DSSC also shows an economic feasibility compare to conventional DSSC which uses ruthenium (Ru) and platinum (Pt) as counter electrode (CE). By the usage of keriang dye and carbon counter electrode, the cost to fabricate a solar cell in a laboratory scale is RM 306.40 compared to RM 506.67 by conventional substances of Ru and Pt which shows a 40% decrement in cost. For a
1.75 m2 of nature based dye-sensitized solar panel which has an output power of 31.5 W
and 3.15 % efficiency, a 1.8 MWp with a 100,000 m2 of PV power generation
production is predicted and shows RM 304.45 per nature based DSSP price compare to
a 30 W monocrystalline solar cell with lower specs and higher pricing of RM 360.00.
This shows that the nature based DSSC not only could provide an adequate amount of
solar cell efficiency, but has a good economic base for further mass production of solar
panels. | en_US |
