Full Paper Pake Aturan Icseea2014

8/10/2019 Full Paper Pake Aturan Icseea2014

http://slidepdf.com/reader/full/full-paper-pake-aturan-icseea2014 1/5



TiO2 and liquid I−/I

3−redox electrolyte, such a system has been studied extensively as a promising alternative to conventional

silicon solar cell technology, have power conversion efficiencies (PCE) exceeding 11% [2]. The DSSC’s efficiency

enhancement can be well understood by examining the relationship between the short circuit current densityand the

iodide ionconductivityand also by the effect of cation adsorption by the TiO2 electrode . According the experiment to

increase the TiO2 film thickness by depositing and calcining TiO2 on FTO twice, which gave TiO2 thickness of about 28–30

µm on various TiO2 samples (P10, P25, meso- TiO2) were used to demonstrate the open circuit voltage dependence on choice

of TiO2 at the TiO2 /NiO interface, displayed high open circuit voltage of 0.7–0.8 V, have a result that Increasing TiO2 layerthickness improved photocurrent generation in bilayer devices due to enhanced dye adsorption in the TiO22 layer [3].

Some of the best or otherwise interesting performance results from the dyesensitized nanostructured TiO2 solar cells

(laboratory scale) shoving the used dye, the cell efficiency, the reported area of the cell and the used illumination in the

efficiency measurement as shown in the table 1.

Table.1

(table reproduced from J. Halme, in Dye-sensitized nanostructured and organic photovoltaic cells:technical review and

preliminary tests, Espoo, Department of Engineering Physics and Mathematics, HELSINKI UNIVERSITY OF

TECHNOLOGY, February 2002, p. 57. )

1.2. Graphene

Graphene is an allotrope of carbon whose structure is a single planar sheet of sp2-bonded carbon atoms that are

densely packed in a honeycomb crystal lattice. The carbon-carbon bond length in graphene is about 0.142 nanometers. Thesurface area of a single graphene sheet is 2630 m2/g [4].

Graphene was made from graphit that obtainable from waste battery. Graphit is the crystaline carbon with form likely

polen and the colour is black. Graphit is the best conductor because it has three orbital that use to make orbital Hybrid sp2

and result three coplanar bound. Graphit has conductivity value 104 S/cm [5].

The physical of graphit are : have the shape solid in the room tempereture; oksidation number are 4 and 2;

electronegativity 2,55 (pauling scala); ionization energy : first =1086,5 kJ/mol; second = 2352,6 kJ/mol; third = 4620,5

kJ/mol; Radius of atom 70 pm; Radius covalent 77 pm; Radius of vanderwaals 170pm; characteristic magnetic =

diamagnetic; sublimation point 4000K; heat vapor 355,8 kJ/mol [6].

For electrical engineers, the high carrier mobility and saturation velocity in graphene offer the promise of graphene-based

high-speedtransistors. The optical properties of graphene are equally impressive. Being atomically thin with a nominal

thickness of merely 3.3 A˚, suspended graphene absorbs a uniform 2.3% of the vertical incident photons from the near-

infrared to visible wavelength ranges through interband transitions [7].



2. Research Method

2.1. Study Literature

Study literature focus on basic principle of the DSSC to get more high efficiency from the material photoelectroda

choosen. Our limit material photoelectroda that discuss in this paper is TiO2 versus graphene. Work priciple of the DSSC sistematically :1). The incoming photon is absorbed by the dye molecule adsorbed on the

surface on the nanocrystalline TiO2 particle and an electron from a molecular ground state S0 is exited to a higher lyingexcited state S*; 2). The exited electron is injected to the conduction band of the TiO2 particle leaving the dye molecule to an

oxidized state S+; 3). The injected electron percolates through the porous nanocrystalline structure to the transparent

conducting oxide layer of the glass substrate (negative electrode, anode) and finally through an external load to the counter-

electrode (positive electrode, cathode). 4). At the counter-electrode the electron is transferred to triiodide in the electrolyte to

yield iodine, and 5). the cycle is closed by reduction of the oxidized dye by the iodine in the electrolyte [8].

According to Matthews, chemical reaction that occur on DSSC can be write as :

For the absorption process, Halme’s research on his thesis shown that the area occupied by one N3 molecule (molecular

structures of three efficient photosensitizers for DSSCs including the so called N3 dye) at the TiO2 surface at full monolayer

coverage is 1.65 nm2 [8].

Halme also mention that the large density of delocalized states in the nanoparticle compared to small number of dye

molecules on the particle surface means that the electron injection to the TiO2 conduction band is associated with an entropy

increase presenting a driving force of approximately 0.1 eV for the charge separation [8].

The stability of the DSSC depends greatly on the designed chemical composition and the materials of the cell as well ason any unwanted impurities possibly included during the preparation of the cells, so too many find researchsshown that

stability from the eksperiment of DSSC not appropriate with the litarature.

Our hyphotesis is with the characteristic graphene such as the thickness of merely 3.3 A˚, condictivity value 104 S/cm, the

length 0.142 nanometers, and the surface area of a single graphene sheet is 2630 m2/g , can replace TiO2 as photoelectroda

for DSSC sandwich structur. If DSSC with graphene as photoelectroda get minimum efficiency 11%, equal with the

efficiency of TiO2 as photoelectroda, it can reduce the cost of the solar cell production.

2.2. Hyphotesis test

figure.1 shown the arrange of thin layer graphene that used to electricity-

producing coating in car (on research Dr. Debmalya Bhattacharya et al ). It get the

Efficiency 30% [4]. Research before it, shown that the efficiency of DSSC using

TiO2 as photoelectroda get 11% [2]. Graphene fabrication method that used Dr.Debmalya Bhattacharya et al is the thick transition metal dichalcogenides (TMDCs),

which the absorption process separated to the four base, they are : Graphene for the

light blue; dichalcogenide for the light white+blue; nanoparticles for the light

gold; boron nitride for the light purple+beige [4].

Figure.1

(figure reproduced from D. Bhattacharya, Waikhomreshmi, V. K. Priya and A. K. Sinha, "Graphene Coated Solar /

Ultracapacitor Driven Car," Int. Journal of Engineering Research and Applications, vol. 3, no. 6, pp. 868, Nov-Dec 2013.)

[8]



Figure.2

(figure reproduced from Wu et al .: “Graphene Electronics : Materials, Devices, and Circuits”, Proceedings of the IEEE ,

vol.101, no.7, pp.1623, July,2013).

Figure.2 is the result reaction simulation from the eksperiment graphene to the light with variying the value of resistance,

conclude that : (a) Experimental output characteristics and simulations for a 70-nm device at room temperature. Back-gate

voltageVg is swept 25 V from the Dirac point with a step of 5 V. (b) Comparison of the measurements and the simulations of

the transfer characteristics of the 70-nm device at room temperature. (c) and (d) Modeling ofGmby varyingRs for 1- m and

70-nm devices, respectively. More than four times improvement ofGmcan be achieved for the 70-nm device [9].

3. Result and discussion

Research about develop graphene in Indonesia not yet take action, moreover research about graphene as photoelectrode forDSSC. The new research in indonesia about photoelectroda for DSSC by using kitosan. The next research focus on solid

electrolit that used to increse the effeciency DSSC. Its phenomenon so dissapointed remembering that considering handlingwaste battery in Indonesia has not been arranged is good enough while its use has increased. So that, research about

graphene as photoelectroda for DSSC sandwhich structur very relevant to develop in di indonesia. Thus the solar cell high performance environmentally friendly with low price can be realized.

4. Conclusion

Our study literature have result grapene that used in two layer for DSSC sandwhich structur can replace TiO2 as

photoelectroda with efficiency more high, that is 30%, whereas TiO2 as photoelectrode with efficiency 11%.

Notiwithstanding the number is not absolute because of stability factor from DSSC that are too susceptible to the impurities,

so that make may be will get the different efficiency with different method, but the value able to approximately with 30 : 11

for the graphene : TiO2.

Full Paper Pake Aturan Icseea2014

Documents

Transcript of Full Paper Pake Aturan Icseea2014