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Light The
Keywords: Energy crisis Group 126: Peter Ehab
Global Warming Mohamed Tarek
Dye sensitized solar cell Ahmed Mostafa

World
conduction band Emad Mohamed
potential difference Abdulla Mohamed
STEM October | Grade 10 | Year 17-18
P.O.C Silicon solar cell DSSCs The Power and The Resistance:
Abstract Name Quantity picture watt 250 250 The power equals to ΔV times the current intensity I . And the
Propanol 10 milliliters resistance equals to ΔV divides the current intensity. From the
Egypt faces countless and terrible grand challenges that impact its development. From two equations we conclude that the power is directly
the most dreadful grand challenges and the most difficult to deal with is lack of energy Price 3000 L.E. 1740 L.E. proportional with ΔV and I and inversely with the resistance.
and its resources which causes what is called an energy crisis. Energy is divided into two TiO2 0.14 Grams Figure 9 shows the active graphite
types, the first type which is commonly used and very dangerous to the environment is
the non-renewable energy. The other type of energy sources are ones that regenerate
Table 3 showing comparison between two solar cell types. Conclusion sheet with the activated carbon
layer.
faster that is used and called renewable sources. The purpose of this study is how to
get the most efficient use out of these renewable sources of energy without harming HNO3 0.6 milliliters
Analysis Finally, we conclude that by using such an electric generator with organic materials which is
cheap, it will produce much energy with less money and we are able to reduce the
the environment, so a solution was chosen to be the dye-sensitive solar cells. It has A JOURNEY THROUGH THE MECHANISM OF THE DSSCs (dye-sensitized solar consumption of electricity from the energy provided by the government. And also as a result
been chosen to achieve the design requirements which are high efficiency and low cell) consists of about 4 layers The transparent conductive layer, the active we decrease the energy used from the non-renewable energies that pollutes the
cost. To conclude, Egypt’s energy crisis is an important problem to be considered and layer, the electrolyte and the counter electrode as shown in figure (7).: Firstly, environment.
solved and this project is going to help to solve this problem. And more details will be Polyethylene glycol-400 10 milliliters the light comes in through the transparent conductive layer to the active layer
revealed in the following sections. where a sensitizer or a dye is found. If the photon has enough energy, it will
knock the electron from the dye from the HOMO (highest occupied molecular
Recommendations
orbit) to the LUMO (lowest unoccupied molecular orbit) where the electron solar tracker
Introduction Methods :
First, to make the natural dye the fresh fruit (the blackberry) was washed
stays there for a specific amount of time called electron recombination time
Figure 7 shows the component of The solar tracker is a device used for orienting solar
and cannot go down again unless after that time finishes. DSSC photovoltaic panel or lens towards the sun as shown in figure
The usage of such non-renewable energy has been increasing with distilled water. They were cut into pieces and grinded as shown
figure (3). 15 ml ethanol were added and they were grinded again then As electrons transfer from high to low levels of energy, the electron that is still in the LUMO goes down (10) by using the solar or light sensors connected to the
so as its resources as shown in figure (1). Two of its resources,
10 ml of acetic acid was added. They were filtered using a filtration to the conduction band of the electron transport layer (the base of the active layer) where it transports machine.
oil and natural gas account for 94% of total energy Figure 3 shows the dye
consumption in Egypt. The level of oil reserves and production paper. The filtrate was used as a sensitizer. Notice that the dye must be preparation. the electron to the transparent conductive layer and this is electron injection, Battery with high efficiency using nanotechnology
has been continuously declining throughout the second half of put in a closed cup to avoid interactions with water vapor in the air. They are pieces of glass coated with a layer of conductive material with to store the energy coming out from the solar cell, we have to
the 1990s and early 2000s; in contrast, consumption has been Second, preparation of DSSC FTO conductive glass sheets was first thickness in nanometers to be transparent enough for the light to pass to the use a good battery that has high efficiency, as some kinds of Figure (10) shows the solar tracker.
persistently increasing. ultrasonically cleaned using a mixture containing 10 ml of ethanol, 10 ml other layers of the solar cell where the energy conversion process begins, and batteries lose energy in the form of heat so we found that the
Figure (1) shows the consumption of propanol and 10 ml of distilled water for 30 minutes. Titanium dioxide all these layers combined are called the photo anode. When the electron best batteries are that which made by Nano graphene layer
The domestic oil consumption started to increase from that has the lowest resistance.
of non renewable energy. (TiO2) powder(2 grams) was set in a shaker and diluted Nitric acid was leaves the dye it leaves behind it an imaginary positive hole in the HOMO of
465,000 barrels in 1990 to 702,000 barrels per day in 2008 as Figure (4) shows the grinded
added(4 ml) as shown in figure (4). Dye and the titanium dioxide the dye, and as these positive holes transfer from low to high energy levels, HIGHER ELECTRON MOBILITY PHOTOANODE
shown in figure (2). The growth in consumption over the
period 2000 to 2008 exceeded 27% and the production has The obtained TiO2 paste was coated using thin film method onto the FTO the valence band of the electron transport layer is chosen to be lower than The usage of TiO2 nanostructured hollow fibers
decreased by 22%. As the decrease in oil production, the clean glass substrate (working electrode) with thickness 10 nm. The the HOMO of the dye. While the redox potential of the third layer which is the instead spherical nanoparticles as shown in figure
dramatical increase in gas production occurs and makes the obtained substrate was set in an electric oven for annealing at 450C for electrolyte and used to compensate the electrons loss from the dye is higher (11), as they are highly porous photo-anodes that
natural gas have a dominance in consumption. The use of gas 30 min in order to eliminate water vapor and the TiO2 molecules to melt than the HOMO of the dye. So the hole goes to is creating a potential exhibit remarkably enhanced electron transport
Figure (11) shows the hollow fiber.
in the electricity sector, industry sector, and petroleum sector together and increase the cohesion as shown in figure (5). This formed difference in the cell and for the electrons to flow. By now the electrolyte is properties compared to mesoscopic films made of
constitute 58.8%, 28.6 and 9.8% respectively of total the pre-prepared TiO2 photoelectrode which is to be sensitized. Figure (5) shows the heating of filled with positive holes, and here comes the rule of the counter electrode to spherical nanoparticles.
Figure (2) shows the production Figure 8 shows the mechanism of
consumption in 2006/2007. and consumption of oil in Egypt. Sensitization was done by putting droplets of the dye in the TiO2 and let Tio2 take the electrons back to the electrolyte creating a whole closed circuit. And the DSSC
this whole process is shown in figure (8). Better counter electrode
titanium absorbed the dye, and the dye molecules to permeate between
Increasing the usage of non-renewable sources like coal and natural gas is considered to The use of silver as a catalyst instead of platinum on FTO as substrate. Such an
the TiO2 pores. The excess dye was washed using H2O and ethanol. The The Active layer:
be a solution, but this solution has more point of weakness that its strength. Its strength inexpensive metal relative to platinum and compatible properties to most of the
cobalt-based (cobalt pyridine) (Co( bpy)3) was used as an electrolyte . This layer is where all the conversion begins, where its rule is to convert photons to electrons and
is generating electricity in huge amount. Its weakness is affecting environment which electrolytes produce less resistance and higher efficiency.
Test plan : transfer them to the FTO. It consists of two parts the semi-conductor and the dye or the sensitizer.
effects on a different form of it ranging from water, air to the soil. It emits gases and Using artificial dye cell
The photoanode (the working electrode) is then attached to the counter The semi-conductor which is also called the electron transport layer because it transfers electrons
toxic material causes a climate change that leads to global warming which harms living N719 dye, is the ammonium salt of N3 dye. With changes to increase cell voltage and
electrode with leaving some space around the corners for the crocodile to the FTO should possess some features where an ideal electron transport layer should:
organism on the earth. So the solution to this problem is to make a project that depends solubility in polar solvents comparing with N3 dye, N719 dye is also one of the most
heads to start the test plan as shown in figure (6). Many different films of (1) Has high internal surface area to enhance dye loading for effective light harvesting.
on the renewable source of energy to produce a huge amount of electricity like solar cell common high performance dyes that are developed for DSSC solar cells.
titanium dioxide has put onto the glass and there efficiency has Figure (6) shows the test (2) be transparent to visible light to avoid photon loss.
stations. The project was chosen to be Dye synthesized solar cell {DSSC}. This project N719 dye has the following features:
measured, then different counter electrode has used and output is plan (3) possess a conduction band sufficiently below the lowest unoccupied molecular orbitals (LUMOs)
should achieve the design requirements of having high efficiency, does not harm the Amphiphilic ( doesn’t react with water), Increased electrostatic binding onto the TiO2
measured, then the new electrolyte has been used and the final output of the sensitizer to allow photo-generated electron injection.
environment and low cost as it made of available and cheap materials as written in the surface at lower pH values, Increased stability, and Increased oxidation potential leading
has been measured. (4) have high electron mobility for efficient electron transport.
next section. to deeper HOMO energy levels and enhanced stability.
Results (5) be inert to the redox electrolyte to reduce electron recombination rate (krec, the rate of electron
recombination from the photo-anode film to the redox mediator)
Materials The titanium absorbance efficiency. (6) possess defects or hydroxyl groups to chemisorb dye molecules onto its surface.
TiO2 Layer:
Literature cited
Name Quantity picture Those properties are mostly found in semi-conductors’ oxides. Some materials have been 1-Hart, T. G. (2015). Energy in Egypt background and issue (First ed.). Retrieved March
investigated like SnO2, TiO2, ZnO2. TiO2 showed the highest efficiency as it has mesoporous 15, -2018, from https://www.americansecurityproject.org/perspective-the-russian-
Blackberry 50 grams
structure which allows the molecules of the dye to fill those pores. Also, it has optimal valence and national-guard/
conduction band and wide band gap to be able to be used with so many dyes aside with the 2-J. (2009). A flexible carbon counter electrode for dye-sensitized solar cells. A Flexible
collection efficiency is being calculated with (ηcoll = k(trans) / (k(trans) + k(rec)), where k(trans), the
Graph 1 shows the collection efficiency of the
Carbon Counter Electrode for Dye-sensitized Solar Cells, 1-5. Retrieved March 29, 2018,
Distilled water 110 milliliters The titanium dioxide showed high efficiency rate at which the photo-generated electrons are transported from the photo-anode film to the
dye at different wave length and different from https://doi.org/10.1016/j.carbon.2009.05.028.
with thickness of 5nm as shown in graph 1. TIO2 sickness
external contact, and k(rec), the rate of electron recombination from the photo-anode film to the
redox mediator. 3-What is a Dye-Sensitized Solar Cell (DSSC)? - Definition from Techopedia. (n.d.).
The cell efficiency with different counter electrodes. Retrieved April 14, 2018, from https://www.techopedia.com/definition/30957/dye-
Methanol 50 milliliters The electrolyte: sensitized-solar-cell-dssc
the iodine was chosen for the DSSCs for many years due to its stability, however it was shown that 4-Pike, A. (2011). Halliday. Place of publication not identified: Gale Ecco, U S Supreme
is absorbs light at 430 nm wavelength and causes corrosion with many metals that was used as a C.
counter electrode. It also has a big difference between the its redox potential (0.35 v) and the 5-N719 Dye. (n.d.). Retrieved April 14, 2018, from
FTO Conductive glass Two slides 12.5 Cm x 5 Cm table 2 shows a comparison between counter electrode types. HOMO of the dye which is in average equals about 1 v also its closeness to fermi’s level of the TiO2
https://www.ossila.com/products/n719-dye
The cell with pure carbon as counter electrode showed the highest efficiency as shown in limits its open circuit voltage as shown in figure(4). So another alternative was used and its cobalt
table 2. the power that the solar cell generates equals to 0.168 watt per unit area where the based electrolytes. Cobalt tri( bipyridine ) Co( bpy)3 showed the highest efficiency theoretically, as

Cobalt bi-pyrodin 5 milliliters

new electrolyte increases the efficiency by 16%. The efficiency of the solar cell with using the its ΔEOX=5.06, ΔEVHS-LE=-0.2. So (Co(bpy)3)3+/2+ was chosen to be the electrolyte. Acknowledgment
new editions equals to 12%, and the consumption of the electricity provided by the The counter electrode:
government decreases by 36% for one person per month. By comparing the output of Counter electrode consists of two parts the conductor and the catalyst. In most of DSSCs counter First we want to thank Allah and thank all people that helped in making this prototype.
regular silicon solar cell which is 250 w with the output of the DSSC solar panel we need electrode consists of FTO as conductive layer to prevent its corrosion with also commonly used we thanks Doctor Eslam and Doctor Aiat hegazy in the national research center. Also we
Ethanol 10 milliliters (250/0.168 = 1488) solar cell. So by comparing the price of the silicon solar cell panel (3000) iodine as shown above, and Platinum paste is used as a catalyst. But due to the high cost of thanks Doctor Sameh abdulatif for his help in Zewail university . We thanks MR
with the price of solar cell (1488 x 1.17(price of 1 cell)) which equal to 1740.96 we see a high platinum alternatives are investigated and used. Such an alternative is the flexible graphite sheets Mohamed Ali English teacher, MR Hanafy Chemistry teacher , MRS Israa Ali our
difference equaling about 1260 pound as shown in table 3. as conductive layer and activated carbon layer above it that acts as a catalyst as shown in figure (9). Capstone leader, and finally Capstone assistance Mohamed Khaled.

For further information Peter Ehab : 17118@stemegypt.edu.eg | Mohamed Tarek : 17132@stemegypt.edu.eg | Ahmed Mostafa : 17113@stemegypt.edu.eg | Abdulla Mohamed : 17125@stemegypt.edu.eg | Emad Mohamed : 17127@stemegypt.edu.eg