Nonlinear Optics and Quantum Optics, Vol. 00, pp. 1–9
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©2011 Old City Publishing, Inc.
Published by license under the OCP Science imprint,
a member of the Old City Publishing Group
New Type of Photo-Voltaic Cell
Constantin OPREAN, Ion MARGINEAN, Corina BOKOR
Claudiu ISARIE, Rodica CIUDIN and Sorin ITU
Lucian Blaga University of Sibiu
10.Victoriei Blv., Sibiu, 550024, Romania
Received: October 12, 2010. Accepted: December 8, 2011.
Authors studied a cell in which the ions are passing through a permeable
membrane into a transparent reconversion chamber. In dark conditions
the combined suspension of silver and gaseous chlorine results in moving
electrons, produced at the cathode by dissociation of silver chloride. They
are transported by gravitation at the reconversion window where they are
separated from each of the two electrodes and the cycle is repeated with
electron liberation. One important advantage is that the system utilises the
solar light, and the process is equivalent to the water molecules separation
into hydrogen and oxygen. Another advantage is the absorption of solar
energy. The transparent window may be quite large, and the cells can be
electrically connected.
Keywords: photovoltaic cell, solar energy conversion, photovoltaic reverse cell
combustion cell
Introduction
Solar light is one of the most promising and credible renewable energies that
can easily become an important energy resource. More than 50 years ago the
hydrogen combustion cells were already used in order to produce energy.
Hydrogen can be obtained by water electrolyze requiring supply of electricity. By its combustion one obtains again water. The main advantage in this
approach is the fact that the waste is the water, which can be reused and the
final product is the energy provided to the users.
*Corresponding author: [email protected]
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Thus the best, ecofriendly technique, is the decomposition of the wastewater in order to provide the hydrogen and oxygen necessary for combustion
units.
Reverse photovoltaic cells with halogen, can use solar energy for the
photochemical decomposition of some of the most used substances in
photography, which are silver halogens. The decomposition process is the
next step after the catalytic oxide-reduction processes: silver and halogen
used in classical photographic industry forcing the charge flow through the
external circuits occurring the consumer and electron ionization. This process
is associated with electrons ionisers.
In order to divide these two stages, which are both sensitive to light, for the
proposed photovoltaic (PV) cell an LCD window is used:
–– Firstly silver is combined with halogen in no-light environment. This pro-
cess releases electrons through the external circuits.
–– The second stage is silver halogenide decomposition in the main compounds recharging in this way the PV cell in order to combine them again
in no-light environment and thus providing the energy to users.
The LCD window which is externally supplied by pulsating voltage with
a very low consumption and simultaneously for all cells of a battery build as
a panel. The principle of operation of such photovoltaic cells consists on the
use of solar energy in an untraditional way. It means an indirect electrical
energy extraction in order to bring the chemical compounds in their initial
stage after electrochemical transformation of previous stages in which the
electrical energy was produced.
Overview
The schematic structure of the photovoltaic reverse cell with halogen is
shown in figure 1. It has a planar structure containing an anode -1 and a cathode - 2 which are separated by a membrane permeable to halogen ions -3, an
LCD window - 4, external electrical circuits - 5 for electrons flow between
anode and cathode, avoiding membrane, a gas chamber - 6 serving to redirect
the halogen (chlorine) gas to cathode from the anode zone.
The anode is made from thin silver powder which resulted from the photochemical decomposition of silver chloride, settled under the action of gravity on the upper diaphragm no. 3. The cathode is made from a spongy
parallelepiped structure as a reduction catalyst; diaphragm no. 2 is on its
upper surface. The electrical connection that connects the anode is made by
depositing a surface layer as a sieve on the top of diaphragm no. 3 . Through
the sieve holes, the silver powder is sprayed over, in such a way it is provided
the ion’s change.
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FigURE 1
A Schematic structure photovoltaic reverse cell with halogen
FigURE 2
Gravitational deposition of silver atoms on plate
According to figure 2 on top of the anode (1), the silver neutral atoms are
gravitationally deposited. These atoms can lose the electrons from the valence
shell. The space under the porous and catalytic structure of the cathode is
filled with chlorine, which is injected under pressure from the upper layers of
the anode. The photoelectric cell with halogen is functioning in two steps that
succeed each other. These phases are accomplished also by the successive
light-dark steps due to the opacity or transparency of the LCD window.
The first active phase is in no-light or dark environment. At this phase several phenomena are taking place, as shown in figures 3 and 4. At the anode, the
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FigURE 3
Active phase in absence of light illumination
FigURE 4
Capture of electron by chlorine atom
neutral silver atoms become positive silver ions by loosing the valence electron
which will pass through the anode structure (the layer of thin silver powder and
metallic network) to the external circuits and after that to the porous cathode
which contains the chlorine gas. Finally the electron is captured by chlorine
atom to form the stable configuration of octet (fig.4) becoming a negative ion.
This negative ion, which is formed, is captured by the positive silver ions
that are in the anode area. The top of the membrane is permeable to the chloride ions, so they pass through as it is shown in figure 5 joining in this way
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FigURE 5
Passage of chloride ions through the permeable membrane
FigURE 6
Recombination of silver and chloride ions forming AgCl molecule
the positively charged silver ion, which react with chloride ion forming a
AgCl molecule as shown in (fig. 6).
In the second step, the passive one, the LCD window becomes transparent
as shown in figure 7 and the light can flow through the upper layer of silver
chloride which is more sensitive to the light being dicomposed in black powder of silver and chlorine gas. According to figure 8 the silver chloride molecule, that was formed in the first step in no-light environment, could be broken
and the electron captured by chlorine atom in the first stage is recovered by
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Fig.URE 7
The passive stage in which the LCD window becomes transparent
FigURE 8
AgCl molecule decomposes under light into Ag+ and Cl- ions.
silver ion which became again neutral atoms. The chloride ion became again
neutral atoms, placing themselves in the limited space of the cell, creating in
this way a small pressure in the lower space of the cathode (figure 9).
At this moment the LCD window is controlled from outside via an electronic module in order to became opaque. Now the first step, in which the
electrons captured by the silver atoms at anode are redirected to the cathode
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FigURE 9
Small pressure in the lower space of the cathode created by Cl atoms.
FigURE 10
Electrons redirected to the cathode through the external circuit.
is working. Electrons pass through the external circuit and thus the energy is
produced (figure 10).
The voltage generated by such a cell has the value of a half a volt and
depends on the nature of the chloride ion permeable membrane, by the soaked
electrolyte and the cathode catalyst.
This kind of cells can be placed as a panel to form a planar battery. As
shown in figure 12 their electric links can be serial or parallel through the
induced circuits in order to generate higher power at the terminals. An electronic module is ordering the LCD window stages for the entire cell panel to
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Fig. 11
LCD window controlled from an electronic module to become opaque at this step
Fig. 12
Current flow in a series of circuits of photovoltaic cells
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have the two steps simultaneously working in no-light or dark step and in
light environment for all of the photovoltaic cells constituting the panel. The
panel is covered by the LCD window which can became successively transparent or opaque as shown in figure 11 with a frequency of several
tens of hertz. The power provided by the photovoltaic reversible cell panel
with halogen is a pulsed one and may be used mainly for battery or accumulators charging which will then provide the electricity to users during the nighttime.
Conclusions
Photovoltaic reverse cells with halogen convert the solar energy into chemical one. Such cells use chemical substances which are waste of photographic
industry, based on silver halogenides. The electric power supplied by such
photovoltaic cells is provided from sun by the photochemical reactions on
light and no-light control steps.
Acknowledgements
Research conducted under Romanian project POSDRU 7706 Increasing the
role of doctoral studies and doctoral competitiveness in an united Europe cofinanced by European Social Fund through Sectoral Operational Programme
Human Resources Development 2007 – 2013.
References
[1] Oniciu L., Conversia electrochimica a energiei, Editura Stiintifica si Enciclopedica,
Bucuresti 1997.
[2] Popescu I. and Turcu E., Energia incotro?, Editura Scrisul Romanesc, Craiova 1998.
[3] Barla E., Badea G., Predictions on PV Technology Development In theLight of Kyoto
Protocol, The 5th International World Energy System Conference, Mai, 2004.
[4] Markvart T., Castaner L., Technical Handbook of Photovoltaics,Fundamentals and Applications, Elsevier, Ltd, 2003.
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