DESCRIPTION
PHOTOELECTRIC CONVERSION ELEMENT AND METHOD OF PRODUCING
THE SAME
TECHNICAL FIELD
[0001]
The present invention relates to a photoelectric
conversion element such as a solar battery and further to a
method of producing the same.
BACKGROUND ART
[0002]
Generally, a photoelectric conversion element such as
a dye-sensitized type solar battery is made of a reference
electrode constructed by forming a transparent conductive
film on a transparent substrate such as a glass plate and
dyeing the conductive film with a photosensitizing dye, a
counter electrode constructed by forming a transparent
conductive film on a substrate for the counter electrode,
and an electrolyte solution allowed to intervene between
the two electrodes.
[0003]
Further, a photoelectric conversion element is
proposed that improves the electric power generation
efficiency by disposing a brush-shaped carbon nanotube

oriented substantially perpendicularly to the substrate
thereof on the transparent conductive film of the counter
electrode in order to improve the movement of electrons
from the counter electrode to the electrolyte solution (See
Patent Document 1) .
Patent Document 1: Japanese Unexamined Patent
Publication (JP-A) No. 2006-202721
DISCLOSURE OF THE INVENTION
PROBLEMS TO BE SOLVED BY THE INVENTION
[0004]
However, with the photoelectric conversion element
having the above construction, although an improvement in
the power generation efficiency can be expected by
providing a brush-shaped carbon nanotube in the counter
electrode, there arises a problem in that the transparent
conductive film of the counter electrode is corroded
because a corrosive substance such as iodine is contained
in the electrolyte solution.
[0005]
Moreover, in order to orient the brush-shaped carbon
nanotube to the transparent conductive film on the
substrate of the counter electrode, the chemical vapor
deposition method must be used, whereby the substrate and
the transparent conductive film are exposed to high

temperature, thereby raising a problem in that the
materials thereof are limited to those having a heat
resistance.
[0006]
Therefore, an object of the present invention is to
provide a photoelectric conversion element having a high
power generation efficiency, raising no problem of
corrosion, and being applicable to a substrate having a low
heat resistance, as well as a method of producing the same.
MEANS FOR SOLVING THE PROBLEMS
[0007]
The present invention provides a photoelectric
conversion element formed in such a manner that a reference
electrode serving as a negative electrode and a counter
electrode serving as a positive electrode are arranged to
oppose each other, wherein
the reference electrode is constructed by forming a
photocatalyst film dyed with a photosensitizing dye via a
transparent conductive film on one surface of a transparent
substrate, and
the counter electrode is constructed by disposing, on
one surface of a substrate for the counter electrode, a
brush-shaped carbon nanotube oriented substantially
perpendicularly to the substrate surface via a conductive

adhesive agent layer that covers the surface.
[0008]
In the photoelectric conversion element according to
the present invention, the reference electrode is
preferably constructed by allowing a brush-shaped carbon
nanotube disposed substantially perpendicularly to the
substrate surface on the transparent conductive film on the
transparent substrate to carry photocatalyst particles, and
dyeing the particles with a photosensitizing dye.
[0009]
The reference electrode is preferably constructed by
forming a photocatalyst film made of a mixture of carbon
nanotube particles and photocatalyst particles on the
transparent conductive film on the transparent substrate,
and dyeing the catalyst film with a photosensitizing dye.
[0010]
The reference electrode may be in contact with the
brush-shaped carbon nanotube of the counter electrode.
[0011]
The present invention provides a method of producing
a photoelectric conversion element formed in such a manner
that a reference electrode serving as a negative electrode
and a counter electrode serving as a positive electrode are
arranged to oppose each other, wherein
the reference electrode is constructed by forming a

photocatalyst film dyed with a photosensitizing dye via a
transparent conductive film on one surface of a transparent
substrate, and
the counter electrode is constructed by forming, on
one surface of a substrate for the counter electrode, a
conductive adhesive agent layer to cover the surface, and
transcribing a separately formed brush-shaped carbon
nanotube onto the adhesive agent layer in such a manner
that the brush-shaped carbon nanotube may be oriented
substantially perpendicularly to the substrate surface.
[0012]
In the method of producing a photoelectric conversion
element according to the present invention, the reference
electrode is constructed by forming a transparent
conductive film on one surface of a transparent substrate,
transcribing a separately formed brush-shaped carbon
nanotube onto the conductive film in such a manner that the
brush-shaped carbon nanotube may be oriented substantially
perpendicularly to the substrate surface, allowing the
carbon nanotube to carry photocatalyst particles, and
dyeing the particles with a photosensitizing dye.
[0013]
The reference electrode is preferably constructed by
forming a transparent conductive film on one surface of a
transparent substrate, forming a photocatalyst film made of

a mixture of carbon nanotube particles and photocatalyst
particles on the conductive film, and dyeing the catalyst
film with a photosensitizing dye.
[0014]
In forming a photocatalyst film made of a mixture of
carbon nanotube particles and photocatalyst particles on
the transparent conductive film, a paste containing the
mixture is preferably applied, onto the transparent
conductive film, followed by drying. In this case, in
applying the paste onto the transparent conductive film,
the application is preferably carried out in a state in
which an electrostatic field is formed between the
transparent conductive film and the electrode opposing
thereto.
[0015]
In the present invention, the transparent substrate
of the reference electrode may be a glass plate, a plastic
plate, or the like. The transparent conductive film of the
reference electrode is preferably a thin film containing,
for example, a conductive metal oxide such as tin-added
indium oxide [Indium Tin Oxide (TIN)], fluorine-added tin
oxide [Fluorine doped Tin Oxide (FTO)], or tin oxide
[SnO2] .
[0016]
The photosensitizing dye may be, for example, a

ruthenium complex or an iron complex having a ligand
containing a bipyridine structure, a terpyridine structure,
or the like, a metal complex of porphyrin series or
phthalocyanine series, or further an organic dye such as
eosine, rhodamine, merocyanine, or coumalin.
[0017]
The photocatalyst may be a metal oxide such as
titanium oxide (TiO2) , tin oxide (SnO2) , tungsten oxide
(WO3) , zinc oxide (ZnO) , or niobium oxide (Nb2O5) .
[0018]
The substrate for the counter electrode is made of a
metal sheet such as aluminum, copper, or tin.
[0019]
The conductive adhesive agent layer of the counter
electrode may be made of a carbon-series conductive
adhesive agent, but is not limited thereto.
[0020]
In accordance with the needs, an electrolyte solution
may be allowed to intervene between the reference electrode
serving as the negative electrode and the counter electrode
serving as the positive electrode. The electrolyte
solution may be one in which an electrolyte component such
as iodine, iodide ion, or tertiary-butylpyridine is
dissolved in an organic solvent such as ethylene carbonate
or methoxyacetonitrile.

[0021]
The formation and the transcription of the brush-
shaped carbon nanotube is carried out in accordance with
known methods.
EFFECTS OF THE INVENTION
[0022]
According to the present invention, because one
surface of the substrate for the counter electrode is
covered with a conductive adhesive agent layer, even in a
case in which an electrolyte solution containing a
corrosive substance is allowed to intervene between the two
electrodes, the electrolyte solution is not brought into
contact with the substrate. Therefore, the counter
electrode substrate will not be corroded by the electrolyte
solution. This can construct a solar battery cell having a
high electric power conversion efficiency and being
provided with a counter electrode excellent in corrosion
resistance.
[0023]
Also, by transcribing a separately formed brush-
shaped carbon nanotube on one surface of the substrate for
the counter electrode via the conductive adhesive agent
layer, a substrate having a low heat resistance can be
applied and used as the substrate for the counter

electrode.
[0024]
In addition, when the counter electrode is made of a
sheet-shaped electrode and the sheet of the reference
electrode is formed to be provided with a photocatalyst
film, a flexible photoelectric conversion element can be
provided.
[0025]
According to the present invention, movement of
electrons will be improved by the brush-shaped carbon
nanotube of the counter electrode and the carbon nanotube
contained in the photocatalyst, so that a highly efficient
dye-sensitized type solar battery cell can be constructed
even with a smaller amount of electrolyte solution as
compared with that of a conventional one.
BEST MODES FOR CARRYING OUT THE INVENTION
[0026]
Next, in order to describe the present invention
specifically, some Examples of the present invention will
be given.
[0027]
EXAMPLE 1
In Fig. 1, a transparent conductive film (2) was
formed on one surface of a transparent substrate (1) for a

photocatalyst electrode (a reference electrode) made of
glass or plastics. A photocatalyst film (8) made of
titanium oxide particles (3) was formed to a thickness of
10 to 15 µm on the conductive film (2) . The photocatalyst
film (8) was formed by applying a paste containing titanium
oxide particles having an average particle size of 20 to 30
nm onto the transparent substrate (1), followed by
sintering.
[0028]
After the photocatalyst film (8) was dyed with a
ruthenium series dye referred to as "N3" or "N719", the
photocatalyst film (8) was impregnated with an iodine
series electrolyte solution. In this manner, a
photocatalyst electrode (a reference electrode) was
constructed.
[0029]
On the other hand, a carbon series conductive
adhesive agent was applied onto the whole surface of one
surface of a counter electrode substrate (4) made of a
metal sheet. On an adhesive layer (7), a carbon nanotube
formed substantially perpendicularly to a base material
separately by a method such as the thermochemical vapor
deposition method or the plasma chemical vapor deposition
method was transcribed from the base material to the
counter electrode substrate (4) via the conductive adhesive

agent layer (7) so that the carbon nanotube would be
oriented substantially perpendicularly, thereby to form a
counter electrode (positive electrode) (11). An iodine
series electrolyte solution was applied onto the surface
(counter electrode surface) of a carbon nanotube film (5).
The carbon nanotube film (5) of the counter electrode had a
thickness of 20 µm.
[0030]
The photocatalyst electrode (negative electrode) was
disposed to be parallel to the counter electrode (positive
electrode) so that the photocatalyst film (8) of the former
would face the carbon nanotube film (5) of the latter. A
sealing piece (6) made of thermosetting resin or
photosetting resin was allowed to intervene between the
peripheries of the two electrodes, and the two electrodes
were integrated with the sealing piece (6), thereby to
construct a dye-sensitized solar battery cell.
[0031]
On this cell construction, the electric power
conversion efficiency was measured by standard light source
radiation of AM 1.5 and 100 mW/cm2, with a result that the
conversion efficiency was 5.6%.
[0032]
With a solar battery cell constructed by using a
conventional paste containing a carbon nanotube, the

electric power conversion efficiency is about 2 to 3%, so
that an electric power conversion efficiency of a high
value of about the double has been obtained. This is
because a circuit formation having a low electric
resistance has been made by a substantially perpendicular
carbon nanotube.
[0033]
In addition, the corrosiveness by the iodine series
electrolyte solution applied onto the surface of the
counter electrode was examined. As a result thereof, it
was confirmed that the counter electrode surface did not
change from the initial state, and is excellent in
durability.
[0034]
EXAMPLE 2
In Fig. 2, to a transparent substrate (1) made of
glass or plastics whose surface is covered with a
transparent conductive film (18) such as ITO, a transparent
conductive film (2) of conductive polymer such as PEDOT or
PEDOT/PSS was formed on this transparent conductive film.
Separately, a carbon nanotube formed substantially
perpendicularly to a base material by a method such as the
thermochemical vapor deposition method or the plasma
chemical vapor deposition method was transcribed from the
base material to the transparent conductive film (2) so

that the carbon nanotube would be oriented substantially-
perpendicularly. The carbon nanotube film (15) had a
thickness of about 8 µm.
[0035]
Next, as shown in Fig. 4, the substrate (1) with
this carbon nanotube film (15) was immersed into a
dispersion liquid (preferably an alcohol dispersion liquid)
(17) in which titanium oxide particles (having an average
particle size of 20 nm) were dispersed. An electric field
of about -1 kV/cm was formed by a high-voltage power source
(14) between an electrode (13) disposed in the liquid (17)
to oppose to the substrate (1) and the conductive film (2)
of the substrate (1), whereby the titanium oxide particles
(3) were moved into the carbon nanotube film (15) by the
electrophoresis method so as to be carried. Here, the two
are connected so that the conductive film (2) side of the
substrate (1) will be a negative high voltage, and the
electrode (13) side will be grounded.
[0036]
After a photocatalyst film (8) made of the carbon
nanotube film (15) and the titanium oxide particles (3)
carried thereon was dyed with a ruthenium series dye
referred to as "N3" or "N719" , an iodine series electrolyte
solution was applied onto the surface of the photocatalyst
film (8). In this manner, a photocatalyst electrode was

constructed.
[0037]
Instead of the electrophoresis method, after a
solution of chloride or hydroxide which will be a precursor
of a photocatalyst is applied onto the substrate (1) with
the carbon nanotube film, the carbon nanotube film surface
can be allowed to carry predetermined photocatalyst
particles by oxidizing the precursor with use of water
vapor or the like. Alternatively, the carbon nanotube
surface can be allowed to carry photocatalyst particles by
dropping, drying, and sintering a dilution liquid obtained
by diluting a paste containing a photocatalyst such as
titanium oxide particles having an average particle size of
2 0 to 3 0 nm with alcohol or the like.
[0038]
The photocatalyst film (8) made of the carbon
nanotube film (15) and the titanium oxide particles (3)
carried thereon carries the catalyst up to each tube tip
end (the surface of the carbon nanotube film).
[0039]
A counter electrode (positive electrode) (11) was
formed in the same manner as in Example 1.
[0040]
The thickness of the carbon nanotube film (5) of the
counter electrode is 2 0 µm.

[0041]
The photocatalyst electrode (negative electrode) was
disposed to be parallel to the counter electrode (positive
electrode) so that the photocatalyst film (8) of the former
would face the carbon nanotube film (5) of the latter. A
sealing piece (6) made of thermosetting resin or
photosetting resin was allowed to intervene between the
peripheries of the two electrodes, and the two electrodes
were integrated with the sealing piece (6), thereby to
construct a dye-sensitized solar battery cell.
[0042]
On this cell construction, the electric power
conversion efficiency was measured by standard light source
radiation of AM 1.5 and 100 mW/cm2, with a result that the
electric power conversion efficiency was 7.0%. Also, when
a method was carried out in which, instead of the
electrophoresis method, after a precursor solution of a
photocatalyst was applied onto the substrate (1) with the
carbon nanotube film, the carbon nanotube film surface was
allowed to carry predetermined photocatalyst particles by
passing through the precursor oxidization, or when the
photocatalyst particles were allowed to be carried by the
dilution/dropping method, the electric power conversion
efficiency was 6.6 to 6.8%.
[0043]

The conversion efficiency can be further improved by-
optimizing the density of the carbon nanotube film, the
amount of titanium oxide carried thereon, and the like.
[0044]
EXAMPLE 3
In Fig. 3, a transparent conductive film (2) was
formed on one surface of a transparent substrate (1) for a
photocatalyst electrode (a reference electrode) made of
glass or plastics.
[0045]
Separately, a paste was prepared by mixing titanium
oxide photocatalyst particles (having an average particle
size of 2 0 nm) and particles of carbon nanotube (multi-wall
nanotube (MWNT)) having a length of 1 µm (those obtained by
dispersing MWNT into alcohol, finely grinding with use of a
supersonic cleaner, and taking out MWNT of 1 µm or less
with use of a filter), and adding alcohol and water to this
mixture. In this Example, MWNT was used as the carbon
nanotube; however, a single wall nanotube (SWNT) or a
double wall nanotube (DWNT) may be used as well.
[0046]
This paste was applied onto the transparent
conductive film (2) on the transparent substrate (1) with
use of a doctor blade to form a film, which was then dried
at a temperature of 150°C, so as to form a photocatalyst

film (8) containing titanium oxide particles (3) and carbon
nanotube particles (25) .
[0047]
In this Example, the film was formed by using a paste
containing titanium oxide particles (3) and carbon nanotube
particles (25) . Alternatively, the film can be formed by
the electrophoresis method by diluting the above paste
liquid, immersing the substrate (1) with the transparent
conductive film (2) into this dilution liquid, and forming
an electric field of about -1 kV/cm on the substrate side.
In other words, in Fig. 5, to a transparent substrate (1)
made of glass or plastics whose surface is covered with a
transparent conductive film (18) such as ITO, a transparent
conductive film (2) of conductive polymer such as PEDOT or
PEDOT/PSS was formed on this transparent conductive film.
This transparent substrate (1) was immersed into a
dispersion liquid (preferably an alcohol dispersion liquid)
(17) in which titanium oxide particles (3) and carbon
nanotube particles (25) were dispersed. An electric field
of about -1 kV/cm was formed by a high-voltage power source
(14) between an electrode (13) disposed in the liquid (17)
to oppose to the substrate (1) and the conductive film (2)
of the substrate (1), thereby to form a photocatalyst film
(8) containing the titanium oxide particles (3) and the
carbon nanotube particles (25) by the electrophoresis

method. Here, the two are connected so that the conductive
film (2) side of the substrate (1) will be a negative high
voltage, and the electrode (13) side will be grounded.
[0048]
After the photocatalyst film (8) was dyed with a
ruthenium series dye referred to as "N3" or "N719", an
iodine series electrolyte solution was applied onto the
surface of the photocatalyst film (8) . In this manner, a
photocatalyst electrode was constructed.
[0049]
A counter electrode (positive electrode) (11) was
formed in the same manner as in Example 1.
[0050]
The photocatalyst electrode (negative electrode) was
disposed to be parallel to the counter electrode (positive
electrode) so that the photocatalyst film (8) of the former
would face the carbon nanotube film (5) of the latter. A
sealing piece (6) made of thermosetting resin or
photosetting resin was allowed to intervene between the
peripheries of the two electrodes, and the two electrodes
were integrated with the sealing piece (6), thereby to
construct a dye-sensitized solar battery cell.
[0051]
On the cell construction, the electric power
conversion efficiency was measured by standard light source

radiation of AM 1.5 and 100 mW/cm2, with a result that the
conversion efficiency was 6.6%. Also, when the
photocatalyst electrode was fabricated by the
electrophoresis method, the electric power conversion
efficiency was measured by standard light source radiation
of AM 1.5 and 100 mW/cm2 on the constructed dye-sensitized
solar battery cell, with a result that the conversion
efficiency was 6.5 to 6.8%.
[0052]
EXAMPLE 4
In Fig. 6, a transparent substrate (1) for a
photocatalyst electrode (a reference electrode) made of
glass substrate or plastics whose surface is covered with a
transparent conductive film (2) such as ITO was disposed on
an electrode (12) made of metal plate to which a high-
voltage power source (14) was connected. A counter
electrode (13) made of metal plate was disposed to face
this substrate (1). A negative high voltage was applied
between these electrodes (12) (13) to form an electrostatic
field. Here, the two are connected so that the electrode
(12) side will be a negative high voltage, and the counter
electrode (13) side will be grounded.
[0053]
In this Example, an electric field of -1.5 to -2
kV/cm was formed between the electrodes.

[0054]
In this state, a paste containing a mixture of a
photocatalyst such as titanium oxide particles (3) and
carbon nanotube particles (25) finely ground by a
supersonic cleaner was applied onto the transparent
electrode film. Further, the paste was extended with use
of a doctor blade (16) formed, by a spatula made of resin so
that the paste surface would be uniform, thereby to form a
coating film.
[0055]
The carbon nanotube particles contained in a
dispersion form in this coating film will move to the
substrate (1) side by the electrostatic field formed
between the electrodes, or will be aligned in a
perpendicular direction to the substrate (1) surface in the
photocatalyst layer. Here, no problem is raised even if
the dispersed carbon nanotube particles are tilted slightly
in an oblique direction without being oriented completely
in the perpendicular direction to the substrate (1)
surface.
[0056]
In this state, the wet coating film was dried by warm
wind or hot wind from the outside, and was sintered to form
a photocatalyst film (8) containing titanium oxide
particles (3) and carbon nanotube particles (25) on the

transparent conductive film (2) on the substrate (1).
[0057]
After the photocatalyst film (8) was dyed with a
ruthenium series dye referred, to as "N3" or "N719", an
iodine series electrolyte solution was applied onto the
surface of the photocatalyst film (8). In this manner, a
photocatalyst electrode was constructed.
[0058]
In this Example, the film thickness at the time of
paste application was about 100 µm, and the film thickness
of the photocatalyst layer (8) after drying and sintering
was about 10 µm.
[0059]
A counter electrode (positive electrode) (11) was
formed in the same manner as in Example 1.
[0060]
A dye-sensitized solar battery cell was constructed
in the same manner as in Example 1 from the photocatalyst
electrode (negative electrode) and the counter electrode
(positive electrode).
[0061]
On this cell construction, the electric power
conversion efficiency was measured by standard light source
radiation of AM 1.5 and 10 0 mW/cm2, with a result that the
conversion efficiency was 6.5 to 6.8%.

BRIEF DESCRIPTION OF THE DRAWINGS
[0062]
[FIG. 1] Fig. 1 is a cross-sectional view illustrating a
solar battery cell according to Example 1.
[FIG. 2] Fig. 2 is a cross-sectional view illustrating a
solar battery cell according to Example 2.
[FIG. 3] Fig. 3 is a cross-sectional view illustrating a
solar battery cell according to Example 3.
[FIG. 4] Fig. 4 is a cross-sectional view illustrating the
electrophoresis method in Example 2.
[FIG. 5] Fig. 5 is a cross-sectional view illustrating a
method of forming a photocatalyst layer by the
electrophoresis method in Example 3.
[FIG. 6] Fig. 6 is a cross-sectional view illustrating a
method of forming a photocatalyst layer by the
electrostatic method in Example 4.
DESCRIPTION OF REFERENCE NUMERALS
[0063]
(1) transparent substrate
(2) (18) transparent conductive film
(3) titanium oxide particles
(4) substrate for counter electrode
(5)(15) carbon nanotube film

(5) sealing piece
(6) conductive adhesive agent layer
(8) photocatalyst film
(11) counter electrode
(12)(13) electrode
(14) high-voltage power source
(16) doctor blade
(17) dispersion liquid
(25) carbon nanotube particles

CLAIMS
1. A photoelectric conversion element formed in such
a manner that a reference electrode serving as a negative
electrode and a counter electrode serving as a positive
electrode are arranged to oppose each other, wherein
the reference electrode is constructed by forming a
photocatalyst film dyed with a photosensitizing dye via a
transparent conductive film on one surface of a transparent
substrate, and
the counter electrode is constructed by disposing, on
one surface of a substrate for the counter electrode, a
brush-shaped carbon nanotube oriented substantially
perpendicularly to the substrate surface via a conductive
adhesive agent layer that covers the surface.
2. The photoelectric conversion element according to
claim 1, wherein the reference electrode is constructed by
allowing a brush-shaped carbon nanotube disposed
substantially perpendicularly to the substrate surface on
the transparent conductive film on the transparent
substrate to carry photocatalyst particles, and dyeing the
particles with a photosensitizing dye.
3. The photoelectric conversion element according to

claim 1, wherein the reference electrode is constructed by
forming a photocatalyst film made of a mixture of carbon
nanotube particles and photocatalyst particles on the
transparent conductive film on the transparent substrate,
and dyeing the catalyst film with a photosensitizing dye.
4. The photoelectric conversion element according to
claim 3, wherein the reference electrode is in contact with
the brush-shaped carbon nanotube of the counter electrode.
5 . A method of producing a photoelectric conversion
element formed in such a manner that a reference electrode
serving as a negative electrode and a counter electrode
serving as a positive electrode are arranged to oppose each
other, wherein
the reference electrode is constructed by forming a
photocatalyst film dyed with a photosensitizing dye via a
transparent conductive film on one surface of a transparent
substrate, and
the counter electrode is constructed by forming, on
one surface of a substrate for the counter electrode, a
conductive adhesive agent layer to cover the surface, and
transcribing a separately formed brush-shaped carbon
nanotube onto the adhesive agent layer in such a manner
that the brush-shaped carbon nanotube may be oriented

substantially perpendicularly to the substrate surface.
6. The method of producing a photoelectric
conversion element according to claim 5, wherein the
reference electrode is constructed by forming a transparent
conductive film on one surface of a transparent substrate,
transcribing a separately formed brush-shaped carbon
nanotube onto the conductive film in such a manner that the
brush-shaped carbon nanotube may be oriented substantially
perpendicularly to the substrate surface, allowing the
carbon nanotube to carry photocatalyst particles, and
dyeing the particles with a photosensitizing dye.
7. The method of producing a photoelectric
conversion element according to claim 5, wherein the
reference electrode is constructed by forming a transparent
conductive film on one surface of a transparent substrate,
forming a photocatalyst film made of a mixture of carbon
nanotube particles and photocatalyst particles on the
conductive film, and dyeing the catalyst film with a
photosensitizing dye.
8. The method of producing a photoelectric
conversion element according to claim 7, wherein, in
forming a photocatalyst film made of a mixture of carbon

nanotube particles and photocatalyst particles on the
transparent conductive film, a paste containing the mixture
is applied onto the transparent conductive film, followed
by drying.
9. The method of producing a photoelectric
conversion element according to claim 8, wherein, in
applying the paste onto the transparent conductive film,
the application is carried out in a state in which an
electrostatic field is formed between the transparent
conductive film and the electrode opposing thereto.

The present invention provides a photoelectric
conversion element having a high power generation
efficiency, raising no problem of corrosion, and being
applicable to a substrate having a low heat resistance, as
well as a method of producing the same. It is a
photoelectric conversion element formed in such a manner
that a reference electrode serving as a negative electrode
and a counter electrode serving as a positive electrode are
arranged to oppose each other. The reference electrode is
constructed by forming a photocatalyst film (8) dyed with a
photosensitizing dye via a transparent conductive film (2)
on one surface of a transparent substrate (1) . The counter
electrode is constructed by disposing, on one surface of a
substrate (4) for the counter electrode, a brush-shaped
carbon nanotube film (5) oriented substantially
perpendicularly to the substrate surface via a conductive
adhesive agent layer (7) that covers the surface.