JP2018174261A - Method for producing electrode of photoelectric conversion element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an electrode of a photoelectric conversion element capable of suppressing the occurrence of burnout during firing of a laminate having at least two types of layers having different optical characteristics. A method for manufacturing an electrode of a photoelectric conversion element according to the present invention is provided with a first layer having a maximum transmission wavelength of λ1 μm, which exhibits a maximum transmittance in a wavelength range of 0.2 μm or more and 2.7 μm or less, and a maximum transmission wavelength of the first layer. When firing a laminate having a second layer having a λ2 μm larger than λ1, a non-transmitted light energy amount of the first layer is I1 and a non-transmission of the second layer is opaque in a wavelength range of (λ1±0.5) μm. A firing step of firing the laminated body under the condition that the amount of light energy is I2 and I2>I1 is included. [Selection diagram] None

Description

  The present invention relates to an electrode manufacturing method for a photoelectric conversion element.

  In recent years, solar cells have attracted attention as photoelectric conversion elements that convert light energy into electric power. A solar cell is formed by sandwiching a layer contributing to the movement of electrons and holes between a photoelectrode and a counter electrode formed on a substrate. For example, in a dye-sensitized solar cell which is one of solar cells, a photoelectrode comprising a semiconductor layer having a sensitizing dye adsorbed on a photoelectrode substrate, an electrolyte layer, and a counter electrode group On the material, a counter electrode having a catalyst layer is arranged in this order. Furthermore, the photoelectrode can include a conductive film between the photoelectrode substrate and the semiconductor layer.

  In manufacturing an electrode, a composition for forming a semiconductor layer or a catalyst layer is applied on a substrate that may optionally have a conductive film or the like to form a coating film, and the coating film is irradiated with light. For example, there is a case where an operation of applying energy to perform baking is performed. Here, the characteristics of the composition for forming the semiconductor layer and the catalyst layer are different from those of other components such as the base material. For this reason, when light irradiation is performed under conditions sufficient for firing the coating film, burnout may occur in other components.

  Conventionally, there has been proposed a method for producing a semiconductor layer capable of performing a process of firing a semiconductor layer formed on a support including a resin film substrate by applying high energy to such a degree that the resin film substrate is deformed ( For example, see Patent Document 1). In the method described in Patent Document 1, when the semiconductor layer formed on the substrate is heated by electromagnetic wave irradiation, the substrate that may be a resin film or the like is deformed by performing a step of cooling the substrate. Thus, the semiconductor layer can be fired while effectively suppressing burning.

JP 2012-160394 A

  Here, depending on the step of firing while cooling the support side as described in Patent Document 1, there is a possibility that the burning damage that may occur in other members other than the firing target, such as the base material, cannot be sufficiently suppressed. was there.

  Accordingly, the present invention provides a method for manufacturing an electrode for a photoelectric conversion element capable of suppressing the occurrence of burning when a laminate having at least two types of layers having different optical characteristics is fired. For the purpose.

  The inventor has intensively studied to achieve the above object. And when this inventor includes in a laminated body the 1st layer by which the wavelength which exhibits the maximum transmittance is the short wavelength side, and the 2nd layer by which the wavelength which exhibits the maximum transmittance is the long wavelength side, It was found that burnout is likely to occur. And this inventor advances further examination, and the near-wavelength light which exhibits the maximum transmittance | permeability of this 1st layer suppresses that the light absorption by a 1st layer suppresses burning in a laminated body. The inventors have newly found that this can be effectively suppressed, and have completed the present invention.

This invention aims to solve the above-mentioned problem advantageously, and the electrode manufacturing method of the photoelectric conversion element of the present invention is the maximum exhibiting the maximum transmittance in the wavelength range of 0.2 μm or more and 2.7 μm or less. In firing a laminate having a first layer having a transmission wavelength of λ ₁ μm and a second layer having a maximum transmission wavelength of λ ₂ μm greater than λ ₁ , (λ ₁ ± 0.5) μm in the wavelength range of the non-transmitted light energy of the first layer I _1, the non-transmitted light energy of the second layer as I _2, firing the laminate under conditions satisfying I _2> I ₁ It includes a firing step.
According to the electrode manufacturing method of the present invention, it is possible to suppress the occurrence of burnout when firing a laminate having at least two types of layers having different optical characteristics.
In the present specification, “non-transmission light energy of the first layer” means light energy that does not pass through the first layer among light energy that can be supplied to the laminate in the firing step. In other words, “non-transmitted light energy” means light energy that can be reflected or absorbed by the first layer among light energy that can be supplied to the laminate in the firing step. The same applies to “non-transmission light energy of the second layer”.
Then, the non-transmission light energies I ₁ and I ₂ can be calculated by the method described in the examples of this specification.

Further, in the method of manufacturing an electrode photoelectric conversion element according to the present invention, it is preferable that the light transmittance T ₁ of the said at wavelength 1.0μm first layer is 70% or more. If the light transmittance T ₁ of the first layer at a wavelength of 1.0μm is 70% or more, in the firing step, that burning in the first layer is generated it can be better suppressed.
Here, the light transmittance T ₁ can be measured based on JIS K 7361.

Further, in the method of manufacturing an electrode photoelectric conversion element according to the present invention, it is preferable the value of I 2 _/ I ₁ is 1.1 or more. If the value of I ₂ / I ₁ is 1.1 or more, the occurrence of burnout in the first layer can be suppressed more satisfactorily.

  Moreover, in the electrode manufacturing method of the photoelectric conversion element according to the present invention, it is preferable that the firing step includes irradiating the laminated body with light through a filter. By using the filter, it is possible to more effectively suppress the occurrence of burning in the first layer.

  Moreover, the electrode manufacturing method of the photoelectric conversion element which concerns on this invention WHEREIN: It is preferable that the said filter is equipped with the light control layer laminated | stacked on the support body. If the filter has a light control layer on the support, it is possible to more effectively suppress the occurrence of burnout by efficiently reducing light in a desired wavelength region.

Moreover, in the electrode manufacturing method of the photoelectric conversion element according to the present invention, the filter has a minimum value of light transmittance in a wavelength range of 0.7 μm or more and 1.3 μm or less, I _min (%), 2.0 μm or more. It is preferable that the filter satisfy I _min / I _max ≧ 0.90, where I _max (%) is the maximum value of light transmittance in a wavelength range of 6 μm or less. If the filter used in the firing step satisfies the conditions, firing can be promoted while suppressing the occurrence of burnout in the laminate.
The light transmittance of the filter can be measured based on JIS R 3106.

  ADVANTAGE OF THE INVENTION According to this invention, it is possible to provide the electrode manufacturing method of a photoelectric conversion element which can suppress generation | occurrence | production of burnout at the time of baking of the laminated body which has at least 2 type of layer from which an optical characteristic differs. It becomes.

  Hereinafter, embodiments of the present invention will be described in detail. The method for producing an electrode of a photoelectric conversion element of the present invention is suitably implemented in any case where firing of a laminate having at least two types of layers having different optical characteristics, at least one of which is a firing target, may be required. can do. In particular, the method for producing an electrode of a photoelectric conversion element of the present invention can be suitably used when forming electrodes of solar cells such as dye-sensitized solar cells, organic thin film solar cells, and perovskite solar cells.

  First, a schematic configuration of a dye-sensitized solar cell as an example of a photoelectric conversion element including an electrode that can be produced according to the method for manufacturing an electrode of a photoelectric conversion element of the present invention will be described. The dye-sensitized solar cell is not particularly limited, and a photoelectrode substrate including a photoelectrode including a porous semiconductor layer, and a counterelectrode substrate including a counterelectrode including a catalyst layer include an electrolyte layer. And a dye-sensitized solar cell having a general structure in which the porous semiconductor layer side and the catalyst layer side are arranged to face each other. Furthermore, the dye-sensitized solar cell may include a conductive film between the base material and the porous semiconductor layer, and between the catalyst layer and the counter electrode base material. The photoelectrode includes a porous semiconductor layer and a photoelectrode-side conductive film. The counter electrode includes a catalyst layer and a counter electrode side conductive film. Furthermore, the photoelectrode side conductive film and the counter electrode side conductive film are connected by wiring, and when the dye adsorbed in the porous semiconductor layer is excited by light and emits electrons, the photoelectrode side conductive film and the counter electrode side conductive film are connected through the wiring from the photoelectrode side. Electron flow that reaches the back electrode and returns to the photoelectrode through the electrolyte layer is generated. In this way, the dye-sensitized solar cell converts light energy into electrical energy.

  The photoelectrode substrate can be a conductive sheet formed using a metal, a metal oxide, a carbon material, a conductive polymer, or the like, or a nonconductive sheet made of resin, glass, and silicon. Among these, a transparent resin is often used as the base material. Transparent resins include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), syndiotactic polystyrene (SPS), polyphenylene sulfide (PPS), polycarbonate (PC), polyarylate (PAr), polysulfone (PSF), polyester sulfone. Examples thereof include synthetic resins such as (PES), polyetherimide (PEI), transparent polyimide (PI), and cycloolefin polymer (COP).

  The porous semiconductor layer is a porous semiconductor layer. The porous material for forming the porous semiconductor layer is not particularly limited, for example, various metal oxide semiconductors such as titanium oxide, zirconium oxide, zinc oxide, vanadium oxide, niobium oxide, tantalum oxide, tungsten oxide, Various metal oxide semiconductors such as strontium titanate, calcium titanate, magnesium titanate, barium titanate and potassium niobate, transition metal oxides such as magnesium oxide, strontium oxide, aluminum oxide, cobalt oxide, nickel oxide and manganese oxide And lanthanoid oxides such as cerium oxide, gadolinium oxide, samarium oxide and ytterbium oxide, and natural or synthetic silicate compounds represented by silica. These materials may be used alone or in combination. Furthermore, although the thickness of a porous semiconductor layer is not specifically limited, Usually, it is 0.1-250 micrometers.

  The dye adsorbed on the porous semiconductor layer is a compound (sensitizing dye) that can be excited by light and pass electrons to the porous semiconductor layer. Such a sensitizing dye is not particularly limited, and may be a dye that can be used in a dye-sensitized solar cell, such as a metal complex dye.

  The electrolyte layer is a layer for separating the photoelectrode and the counter electrode and efficiently performing charge transfer. The electrolyte layer usually contains a supporting electrolyte, a redox couple (a pair of chemical species that can be reversibly converted into an oxidized form and a reduced form in a redox reaction), a solvent, and the like.

  The catalyst layer is formed of, for example, a platinum layer or a carbon layer. In particular, the carbon layer can include fibrous carbon nanostructures. Here, the fibrous carbon nanostructure is not particularly limited, and may be, for example, a carbon nanotube (CNT), a vapor growth carbon fiber, or the like. These may be blended singly or in combination of two or more. Especially, it is preferable that a fibrous carbon nanostructure is a fibrous carbon nanostructure containing CNT. Further, nanosized platinum or the like may be supported on the fibrous carbon nanostructure according to a conventional method. This is because the catalytic effect can be improved.

  The counter electrode base material is for supporting the counter electrode, and is formed of the same material as the base material, for example. Note that the counter electrode base material may be formed of a non-translucent material. Further, the thicknesses of the photoelectrode-side conductive film and the counter electrode-side conductive film are not particularly limited, but are usually 0.1 to 250 μm.

  The photoelectrode side conductive film and the counter electrode side conductive film are made of metals such as platinum, gold, silver, copper, aluminum, indium and titanium; conductive metal oxides such as tin oxide and zinc oxide; indium-tin oxide (ITO ), Composite metal oxides such as indium-zinc oxide (IZO); carbon materials such as fibrous carbon nanostructures and fullerenes; and combinations of two or more thereof. The conductive film can be connected to the wiring.

(Electrode manufacturing method)
The electrode manufacturing method of the present invention that can be used in manufacturing the photoelectrode and the counter electrode of the dye-sensitized solar cell that can have the above-described schematic configuration will be described in detail below. In addition, in the following description, the case where the electrode manufacturing method of this invention is applied at the time of manufacture of the photoelectrode of the said dye-sensitized solar cell is demonstrated as an example.
The electrode manufacturing method of the present invention includes a first layer that exhibits a maximum transmittance in a wavelength range of 0.2 μm or more and 2.7 μm or less, a maximum transmission wavelength of λ ₁ μm, and a maximum transmission wavelength λ _{2 that is} greater than λ _1. In firing the laminate having the second layer of μm, the non-transmitted light energy amount of the first layer in the wavelength range of (λ ₁ ± 0.5) μm is I ₁ , and the non-transmitted light of the second layer It includes a firing step in which the laminate is fired under a condition that satisfies I ₂ > I ₁ where the energy amount is I ₂ . Therefore, the occurrence of burnout can be satisfactorily suppressed during firing of a laminate having at least two types of layers having different optical characteristics such as absorption, reflection, and transmission. The reason why such an effect is obtained by the electrode manufacturing method of the present invention is not clear, but is presumed to be as follows.

That is, the light having the maximum transmittance of each layer included in the laminate is less likely to be absorbed by the layer when compared with light in other wavelength regions, and thus is considered to contribute less to firing of the layer. On the other hand, light other than the wavelength region including the wavelength at which the transmittance of each layer is the maximum transmittance (specified as ± 0.5 μm in the present invention) is easily absorbed by the layer, and therefore, the layer is subjected to firing. The contribution is considered large. Here, in the present invention, in firing a laminate having two types of layers having different maximum transmittances, a wavelength range of 1 μm centering on the maximum transmission wavelength λ ₁ of the first layer (that is, “λ ₁ ± 0. 5 ”μm wavelength range), and the total energy amount I _{1 of} light that does not transmit through the first layer is less than the total energy amount I _{2 of} light that does not transmit through the other layer (second layer). The laminate is fired below. In other words, in the electrode manufacturing method of the present invention, when firing the laminate, the amount of light energy in the wavelength range of “λ ₁ ± 0.5” μm can be absorbed or reflected by the first layer, The firing step is carried out so as to be less than the amount that can be absorbed or reflected by the second layer. Here, in the laminated body which is the object of the present invention, in general, most of the light energy that does not pass through each layer included in the laminated body is absorbed by each layer. And since the energy absorbed in each layer generates heat in each layer, if the energy is absorbed excessively, there is a possibility of causing burning in each layer. Therefore, in the present invention, the first layer is formed by performing the firing step under such a condition that the non-transmission light energy amount I ₁ of the first layer is smaller than the non-transmission light energy amount I _{2 of the second} layer. Compared to the second layer, it is possible to heat under mild conditions, and it is surmised that firing of the second layer can be accelerated while favorably suppressing the occurrence of burnout in the first layer. .

  Here, for the first layer and the second layer, “the maximum transmission wavelength exhibiting the maximum transmittance in the wavelength range of 0.2 μm to 2.7 μm” is the wavelength range of 0.2 μm to 2.7 μm (hereinafter, In the case of generating a transmittance curve with the horizontal axis representing the wavelength and the vertical axis representing the transmittance in the “wavelength range A”), when only one value with the maximum transmittance value can be detected , Meaning the wavelength corresponding to such transmittance. The so-called “saturated state” in which the slope of the tangent line of the transmittance curve is zero in a certain wavelength range B included in the wavelength range A and the transmittance value is the maximum transmittance in the wavelength range A. ”Is detected, the wavelength at the center point of the wavelength range B is defined as“ the maximum transmission wavelength exhibiting the maximum transmittance in the wavelength range of 0.2 μm to 2.7 μm ”.

  The electrode manufacturing method of the present invention includes an optional preparation step and a firing step. Hereinafter, each step will be described.

<Preparation process>
In the preparatory step, on the photoelectrode substrate as described above, the photoelectrode-side conductive film that is the first layer, and the second layer, the firing precursor film for the porous semiconductor layer that can become a porous semiconductor layer by firing, Form. Regardless of this example, the first layer and the second layer are exposed on the surface at different positions on at least one surface of the laminate. For example, the second layer is laminated on a part of the first layer, and in the portion on the surface where the second layer is laminated, the second layer forms the outermost surface of the laminate, In the part on the surface where is not laminated, the first layer or the substrate may form the outermost surface of the laminate.

The photoelectrode-side conductive film as the first layer is not particularly limited, and can be formed by a known method such as a sputtering method or a coating method using the metal oxide or carbon material as described above. Furthermore, the light transmittance T ₁ of the first layer at a wavelength of 1.0 μm is preferably 70% or more. This is because if the light transmittance T ₁ of the first layer at a wavelength of 1.0 μm is 70% or more, it is possible to more effectively suppress the occurrence of burnout in the first layer in the subsequent firing step. .

  On the first layer formed in this manner, a coating film is formed using the composition containing the porous material described above according to a known coating film forming method such as coating or printing, and the second layer is porous. A fired precursor film for a porous semiconductor layer can be formed.

<Baking process>
In the baking step, in the wavelength range of (λ ₁ ± 0.5) μm, a non-transmitted light energy of the first layer _{I 1,} the non-transmitted light energy of the second layer as _{I 2, I 2> I 1} The laminate is exposed to light. Here, I ₁ and I ₂ can be calculated according to the method described in the examples of the present specification. Further, the value of I ₂ / I ₁ is preferably 1.1 or more, more preferably 1.5 or more, and preferably 10.0 or less, more preferably 5.0 or less. preferable. If the value of I ₂ / I ₁ is greater than or equal to the above lower limit value, the first layer can be more satisfactorily prevented from burning. Moreover, if the value of I ₂ / I ₁ is equal to or less than the above upper limit value, firing of the laminate can be efficiently promoted while favorably suppressing burnout of the first layer.

Here, the light source that is an energy source that can be used in the firing step is not particularly limited, and a general light source such as a heating light source that can be used when manufacturing an electrode of a photoelectric conversion element is used. be able to. When the light source to be used is a light source that does not irradiate light in a part of the wavelength range of (λ ₁ ± 0.5) μm, the irradiation wavelength range of the light source and (λ ₁ ± 0. 5) I ₁ and I ₂ can be calculated for the overlapping wavelength range with the μm wavelength range, respectively.

In the firing step, it is necessary to set the conditions so that I ₂ > I ₁ . To that end, 1) adjusting the irradiation energy distribution of the light source itself to create a light condition that satisfies I ₂ > I _1, and 2) performing a firing process on the laminate through a filter It is possible to adjust the energy distribution of the light reaching the laminate by irradiating light, and to perform the firing step so that the light conditions are such that I ₂ > I ₁ .

  As a specific method in the case of performing the firing step as in 1), for example, adjusting the color temperature of light irradiated from a light source can be mentioned. The irradiation energy distribution of the light source can be changed by adjusting the color temperature. More specifically, for example, by setting the color temperature high, the peak of the irradiation energy distribution can be made shorter than that when the color temperature is set low.

When performing the firing step as in 2), it is preferable to use a filter that satisfies the following light transmittance conditions. That is, the filter sets the minimum value of light transmittance in the wavelength range of 0.7 μm to 1.3 μm to I _min (%) and the maximum value of light transmittance in the wavelength range of 2.0 μm to 2.6 μm to I. It is preferable that the filter satisfies I _min / I _max ≧ 0.90 as _max (%), more preferably satisfies I _min / I _max ≧ 1.5, and 20.0 ≧ I _min / I _max It is preferable to satisfy. If the filter used in the firing step satisfies the above conditions, firing can be further promoted while suppressing the occurrence of burnout in the laminate. In this manner, the filter can preferentially transmit the light on the short wavelength side, and can preferentially reduce the light on the long wavelength side, thereby effectively suppressing the occurrence of burning in the laminate.

  Such filters are not particularly limited, and glass such as quartz glass, synthetic quartz glass, soda glass, borosilicate glass, and float glass; and resin films such as polyethylene terephthalate film, polyimide film, and polycarbonate film The support may be comprised of. The filter may be a single layer or may have a plurality of layers. For example, the filter may be a filter in which a light control layer is formed on a support made of glass or a resin film.

Such a light control layer can be made of, for example, a dielectric material. Dielectric materials include, for example, high refractive index materials such as TiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₃ , and Ta ₂ O ₅ ; low refraction such as SiO ₂ , MgF ₂ , and SiON Rate material. Among them, it is preferable to use at least one of TiO ₂ and Ta ₂ O ₃ as the high refractive index material and at least one of SiO ₂ and MgF ₂ as the low refractive index material. These high refractive index materials can be used singly or in combination. The same applies to the low refractive index material. The light control layer may have at least a layer made of a low refractive index material (hereinafter also referred to as “low refractive index layer”). Furthermore, by alternately laminating a low refractive index layer and a layer made of a high refractive index material (hereinafter also referred to as a “high refractive index layer”) as a light control layer, light incident on the light control layer can be obtained. Of these, a light control layer capable of preferentially dimming light in a specific wavelength range can be obtained. In addition, the low refractive index layer and the high refractive index layer which comprise a light control layer can be formed in accordance with known film-forming methods, such as sputtering method and a coating method. Moreover, the thickness of each layer can be set arbitrarily.

  Moreover, the light control layer may be comprised with the light absorptive material, for example. As a light absorptive material, fluorine dope tin oxide (FTO) is mentioned, for example. The light control layer can be formed by depositing a light absorbing material according to a known film deposition method such as vapor deposition. Moreover, the thickness of the light control layer which consists of a light absorptive material can be set arbitrarily.

If the filter has a light control layer, light in a desired wavelength region can be efficiently reduced. The material of the support and the light control layer can be appropriately selected so that a light condition that satisfies I ₂ > I ₁ can be created. For example, the glass that can be used as the support is preferably composed mainly of SiO _2, that is, the content of SiO ₂ is preferably 50% by mass or more, and substantially contains no impurities (ie, the content of SiO ₂ Is more preferably 99.99% by mass or more). Especially, a filter provided with the light control layer which consists of the above materials by using glass as a support body is preferable. Here, “light control” means that light having a certain energy distribution emitted from a light source is emitted as an energy distribution different from that at the time of incidence. In the filter of the present invention, not only an arbitrary light control layer but also the support itself can contribute to satisfy the conditions in the firing step as described above by exhibiting the light control function. In addition, the light control layer may be arrange | positioned at the surface at the side of the light source of a support body, and may be arrange | positioned at the surface on the opposite side (namely, laminated body side) from a light source.

  Of the methods for adjusting the light energy distribution described as 1) and 2) above, the viewpoint of better suppressing the occurrence of burnout in the first layer, the ease of control of the irradiation conditions, and the control method From the viewpoint of versatility, it is preferable to perform the firing step using a filter as in 2) above.

  Furthermore, the light irradiation time in a baking process can set suitably the time required and sufficient for baking of a laminated body. The light irradiation time can be, for example, 1 second or more and 100 seconds or less. Moreover, the atmosphere at the time of implementing a baking process is not specifically limited, For example, it may be a normal temperature atmospheric pressure air atmosphere according to JISZ8703.

  The fired laminate obtained through such a firing step can be used as a photoelectrode of the dye-sensitized solar cell as described above by adsorbing the dye to the porous semiconductor layer according to a known method. And the dye-sensitized solar cell can be manufactured by combining the obtained photoelectrode with the counter electrode or the electrolyte layer as described above according to a known method.

EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these Examples. In Examples and Comparative Examples, the maximum transmission wavelength of the first layer and the second layer provided in the laminate, the amount of non-transmitted light energy of each layer, and I _mim (%) and I _max (%) of the filter are as follows. The measurement was performed as described above. Further, in the examples and comparative examples, the presence or absence of burnout in the obtained first layer and the battery characteristics were evaluated as follows.

<Maximum transmission wavelength>
First, in order to measure the maximum transmittance in the wavelength range of 0.2 μm or more and 2.7 μm or less of the first layer and the second layer, a test piece was prepared. In the examples and comparative examples, a test piece was prepared by cutting a sheet having a thickness of 200 μm using the same material as that used for forming the first layer and the second layer. Then, the test piece was irradiated with light having a wavelength range of 0.2 μm or more and 2.7 μm or less using a light source (manufactured by JASCO Corporation, “ultraviolet visible near infrared spectrophotometer”), and passed through the test piece. The energy of light was measured with a photometer (manufactured by JASCO Corporation, “UV-Visible Near-Infrared Spectrophotometer”). About the light radiate | emitted from a light source, it measured with the photometer similarly about the light which does not pass a test piece. Based on these measurement data, the transmittance curve of each test piece was obtained.
From the obtained transmittance curve, the maximum transmittance of the first layer is 83% when the irradiation wavelength is 1.0 μm, and the maximum transmittance of the second layer is 90% when the irradiation wavelength is 2.3 μm. Got to be. Therefore, the maximum transmission wavelength λ ₁ exhibiting the maximum transmittance in the wavelength range of 0.2 μm or more and 2.7 μm or less of the first layer was determined to be 1.0 μm, and the maximum transmission wavelength λ ₂ was determined to be 2.3 μm. Further, the light transmittance T ₁ of the first layer at a wavelength of 1.0 μm was 83%.
<Non-transmitted light energy amount of each layer>
The non-transmission energy amount (I) at each wavelength was calculated based on the following formulas for the examples and comparative examples.
I [J] = E [J] × ^TF [%] / 100 × (100−light transmittance [%] of the first layer or the second layer) / 100
In the above formula,
I: amount of non-transmitted light energy of first layer at wavelength λ _x [J]
E: Radiant energy of light source at wavelength λ _x [J]
T ^F : Light transmittance [%] of the filter at the wavelength λ _x, “100” when no filter is arranged
T ^L : Light transmittance of the first layer or the second layer [%]
The calculated value of I was plotted with the X axis as the wavelength and the Y axis as (I) above, and curve approximation was performed. For the obtained curve, the area covered by the X-axis and the curve in the wavelength range of (λ ₁ ± 0.5) μm is calculated, and the calculated value for the plot obtained using the light transmittance of the first layer is The calculated value for the plot obtained using I ₁ and the light transmittance of the second layer was defined as I ₂ .

<Filter I _mim (%) and I _max (%)>
The filter used in Examples and Comparative Examples was irradiated with light having a wavelength range of 0.2 μm or more and 2.7 μm or less using a light source (manufactured by JASCO Corporation, “Ultraviolet Visible Near Infrared Spectrophotometer”). The light transmitted through the filter was measured with a photometer (manufactured by JASCO Corporation, “UV-Vis-NIR Spectrophotometer”). Regarding the light emitted from the light source, the light not passing through the filter was similarly measured with a photometer. And from these measurement data, the value of the light transmittance in each wavelength was calculated, and the transmittance curve was obtained (JIS R 3106). From the obtained transmittance curve, the minimum value I _min (%) of the light transmittance in the wavelength range of 0.7 μm to 1.3 μm and the maximum of the light transmittance in the wavelength range of 2.0 μm to 2.6 μm. The value I _max (%) was determined respectively. The results are shown in Table 1.

<Presence of burnout in the first layer>
The 1st layer obtained through the baking process according to an Example and a comparative example was observed visually, and it evaluated according to the following references | standards.
A: Burnout is not recognized at all.
B: Burnout is observed in less than 20% of the entire light receiving surface area of the first layer.
C: Burnout is observed in 20% or more of the entire light receiving surface area of the first layer.

Example 1
<Preparation process>
On one surface of a polyethylene naphthalate film as a photoelectrode substrate, indium tin oxide (ITO) was sputtered as a first layer to form a photoelectrode-side conductive film. On the ITO surface of the obtained photoelectrode substrate with an electrically conductive film (ITO-PEN film, film thickness: 200 μm, ITO thickness: 200 nm, sheet resistance 15 Ω / sq.), Firing for porous semiconductor layer as the second layer A binder-free titanium oxide paste (manufactured by Pexel Technologies, "PECC-C01-06") containing titanium oxide as a porous material for forming the precursor film is applied to a coating thickness of 150 μm using a Baker type applicator. It was applied to form a coating film. The coating film was formed in such a shape as to cover a part of the surface of the photoelectrode-side conductive film. That is, the photoelectrode side conductive film as the first layer and the firing precursor film for the porous semiconductor layer as the second layer were exposed on the light receiving side surface of the laminate.
After drying the obtained coating film at room temperature for 10 minutes, a low refractive index layer and a glass support (made of quartz glass, SiO ₂ content of 99.99% or more) above the light receiving side surface of the laminate A filter in which a light control layer having a plurality of high refractive index layers was formed was disposed. The I _mim (%) and I _max (%) of the filter measured according to the above were as shown in Table 1.
<Baking process>
A light source (“Halogen heater” manufactured by Iwasaki Electric Co., Ltd.) was used to irradiate light having a wavelength range of 0.2 μm to 2.7 μm (irradiation conditions: color temperature 2500 K, peak wavelength 1.2 μm, irradiation time 10 seconds). About the obtained baked laminated body, the presence or absence of burnout was determined according to the above. The results are shown in Table 1.

(Examples 2 to 4)
A dimming layer comprising a plurality of low refractive index layers and multiple high refractive index layers is formed on a glass support, and the filter used in the firing step exhibits I _mim (%) and I _max (%) as shown in Table 1. A fired laminated body was obtained by carrying out the firing step in the same manner as in Example 1, except that the filters were changed to the respective filters. Furthermore, the same evaluation as in Example 1 was performed. The results are shown in Table 1.

(Example 5)
Except for changing the filter used in the firing process to a filter made of only glass as a support without a light control layer ( _presenting I _mim (%) and I _max (%) as shown in Table 1). A firing process was performed in the same manner as in Example 1 to obtain a fired laminate. Furthermore, the same evaluation as in Example 1 was performed. The results are shown in Table 1.

(Example 6)
A fired laminate was obtained by carrying out the firing process in the same manner as in Example 1 except that the irradiation conditions in the firing process were changed to a color temperature of 1500 K, a peak wavelength of 1.9 μm, and an irradiation time of 10 seconds. Furthermore, the same evaluation as in Example 1 was performed. The results are shown in Table 1.

(Comparative Example 1)
The filter used in the firing step is changed to a filter made of only glass as a support having no light control layer ( _presenting I _mim (%) and I _max (%) as shown in Table 1), and A fired laminate was obtained by carrying out the firing step in the same manner as in Example 1 except that the irradiation conditions were changed to a color temperature of 1000 K, a peak wavelength of 2.9 μm, and an irradiation time of 10 seconds. Furthermore, the same evaluation as in Example 1 was performed. The results are shown in Table 1.

(Comparative Example 2)
A fired laminate was obtained by carrying out the firing step in the same manner as in Example 1 except that no filter was used in the firing step and the irradiation conditions were changed to a color temperature of 1000 K, a peak wavelength of 2.9 μm, and an irradiation time of 10 seconds. Got. Furthermore, the same evaluation as in Example 1 was performed. The results are shown in Table 1.

  In Table 1, “PEN” represents polyethylene naphthalate, and “ITO” represents indium-tin oxide.

From Table 1, a laminate including a layer made of indium-tin oxide as a first layer and a layer made of titanium oxide as a second layer on a base material made of polyethylene naphthalate satisfies I ₂ > I ₁ . In Examples 1 to 6 fired under the conditions, it can be seen that the occurrence of burnout in the obtained fired laminate was suppressed.

  According to the present invention, the present invention provides an electrode manufacturing method for a photoelectric conversion element capable of suppressing the occurrence of burnout when a laminate having at least two types of layers having different optical characteristics is fired. can do.

Claims (6)

A first layer having a maximum transmission wavelength of λ ₁ μm exhibiting a maximum transmittance in a wavelength range of 0.2 μm to 2.7 μm, and a second layer having a maximum transmission wavelength of λ ₂ μm greater than λ ₁ In firing the laminate having
In the wavelength range of (λ ₁ ± 0.5) μm, the non-transmission light energy amount of the first layer is I ₁ , and the non-transmission light energy amount of the second layer is I ₂ , so that I ₂ > I ₁ is satisfied. Including a firing step of firing the laminate under conditions,
A method for manufacturing an electrode of a photoelectric conversion element. Light transmittance T ₁ of the said at wavelength 1.0μm first layer is 70% or more, the method of manufacturing an electrode photoelectric conversion device according to claim 1. The method for producing an electrode of a photoelectric conversion element according to claim 1 or 2, wherein the value of I ₂ / I ₁ is 1.1 or more.   The electrode manufacturing method of the photoelectric conversion element according to any one of claims 1 to 3, wherein the firing step includes irradiating the laminated body with light through a filter.   The electrode manufacturing method of the photoelectric conversion element of Claim 4 provided with the light control layer by which the said filter was laminated | stacked on the support body. The filter has a minimum value of light transmittance in a wavelength range of 0.7 μm or more and 1.3 μm or less, I _min (%), and a maximum value of light transmittance in a wavelength range of 2.0 μm or more and 2.6 μm or less is I _max. The electrode manufacturing method for a photoelectric conversion element according to claim 4, wherein the filter satisfies I _min / I _max ≧ 0.90 as (%).