JP2018174174A - Photoelectric conversion element and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide: a photoelectric conversion element with high durability; and a method for manufacturing a photoelectric conversion element, by which a photoelectric conversion element with high durability can be efficiently manufactured.SOLUTION: A photoelectric conversion element comprises: a first electrode 13; a second electrode 14; and a photoelectric conversion layer 16 held between the first electrode 13 and the second electrode 14. The photoelectric conversion layer 16 includes particles including a perovskite compound represented by ABXas a constituent material. The particles have an average particle diameter of 0.10 μm or more and 0.30 μm or less. According to X-ray diffraction spectra of the particles, a half-value width of a diffraction peak corresponding to a cubic crystal (111) peak is as a value of 2θ, 0.12° or more and less than 0.14°. (A represents one or both of a methyl ammonium ion and a formamidinium ion; B represents one or both of Pb and Sn ions; and X's represent ions of one or more kinds selected from a group consisting of F, Cl, Br and I.)SELECTED DRAWING: Figure 1

Description

  The present invention relates to a photoelectric conversion element and a method for manufacturing the photoelectric conversion element.

  In recent years, organic solar cells using organic materials for light absorption and photoelectric conversion have attracted attention. Representative organic solar cells include dye-sensitized solar cells and organic thin-film solar cells, and various studies have been conducted on improving light energy conversion efficiency and durability.

  In recent years, a perovskite solar cell using a perovskite crystal, which is a composite material of an inorganic material and an organic material, has rapidly attracted attention. It is known that perovskite solar cells have excellent light energy conversion efficiency and can be easily produced as a thin film by applying and drying a solution in the same manner as organic solar cells.

For example, Patent Document 1 discloses CH ₃ NH ₃ M ¹ X ₃ (wherein M ¹ is a divalent metal ion, and X is one or more selected from the group consisting of F, Cl, Br, and I). A photoelectric conversion element using a photosensitive material having a perovskite type crystal structure represented by.

JP 2014-72327 A

  However, it is known that the perovskite solar cell as described in Patent Document 1 is likely to deteriorate due to reaction with moisture in the atmosphere. Therefore, improvement in durability is required for industrial application.

  This invention is made | formed in view of the said subject, Comprising: It aims at providing a highly durable photoelectric conversion element. Another object of the present invention is to provide a method for manufacturing a photoelectric conversion element that can efficiently manufacture such a highly durable photoelectric conversion element.

In order to solve the above problems, one embodiment of the present invention includes a first electrode, a second electrode, and a photoelectric conversion layer sandwiched between the first electrode and the second electrode, The conversion layer includes particles having a perovskite compound represented by ABX ₃ as a forming material, the average particle diameter of the particles is 0.10 μm or more and 0.30 μm or less, and in the X-ray diffraction spectrum of the particles, cubic crystals The photoelectric conversion element whose half value width of the diffraction peak corresponding to the (111) peak is 0.12 ° or more and less than 0.14 ° at 2θ.
(In the formula, A is one or both of a methylammonium ion and a formamidinium ion. B is an ion of either or both of Pb and Sn. X consists of F, Cl, Br, and I.) One or more ions selected from the group.)

  In one embodiment of the present invention, an electron transport layer may be provided between the first electrode and the photoelectric conversion layer.

  In one embodiment of the present invention, the electron transport layer may have a structure using an inorganic material as a forming material.

  In one embodiment of the present invention, the electron transport layer may be formed using a conductive oxide as a forming material.

  In one embodiment of the present invention, the electron transport layer may have a structure using zinc oxide as a forming material.

In another embodiment of the present invention, a first solution containing B, which is a cation, X, which is an anion, an organic solvent, and water, is spin-coated on one main surface side of the electrode, and _two layers of BX are formed. And a step of spin-coating the BX ₂ layer with a second solution containing A and C that are cations to form an ABX ₃ layer, wherein A is methylammonium ion and 1 or both formamidinium ions, B is one or both of Pb and Sn, and X is selected from the group consisting of F, Cl, Br and I In the step of forming the BX ₂ layer in the first solution, the first solution contains more than 0% by volume and less than 2% of the water with respect to the organic solvent. From above to the main surface Spray gas Te, in the step of forming the ABX ₃ layer, after dropwise the second solution into the BX ₂ layer was dipped the BX ₂ layer to the second solution, forming the BX ₂ layer BX Provided is a method for manufacturing a photoelectric conversion element in which rotation of the electrode is started and spin-coated after a predetermined time determined based on the crystal state of _two particles.

  According to the present invention, a highly durable photoelectric conversion element can be provided. Moreover, the manufacturing method of the photoelectric conversion element which can manufacture such a highly durable photoelectric conversion element efficiently can be provided.

1 is a schematic cross-sectional view showing a photoelectric conversion element of this embodiment. The flowchart explaining the manufacturing method of the photoelectric conversion element which concerns on this embodiment. The scatter diagram which shows the relationship between the half value width of the diffraction peak corresponding to the (111) peak of a cubic crystal, and the conversion efficiency of the photoelectric conversion element obtained.

[Photoelectric conversion element]
Hereinafter, the photoelectric conversion element according to the present embodiment will be described with reference to FIG. In all the drawings below, the dimensions and ratios of the constituent elements are appropriately changed in order to make the drawings easy to see.

  FIG. 1 is a schematic cross-sectional view showing the photoelectric conversion element of this embodiment. As shown in the figure, the photoelectric conversion element 10 of this embodiment includes a first substrate 11, a second substrate 12, a first electrode 13, a second electrode 14, a hole transport layer 15, a photoelectric conversion layer 16, and an electron transport layer 17. And a sealing portion 18.

(First substrate, second substrate)
In the present embodiment, the first substrate 11 and the second substrate 12 are mainly formed of a light transmissive glass plate or resin. As the first substrate 11 and the second substrate 12, films or sheets of these forming materials can be used.

  Examples of the resin used for such a substrate include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN); polyolefin resins such as polyethylene (PE), polypropylene (PP) and cyclic polyolefin; Resins; Polycarbonate resins; Polystyrene resins; Polyvinyl alcohol resins; Saponified ethylene-vinyl acetate copolymers; Polyacrylonitrile resins; Acetal resins; Polyimide resins.

  Among these resins, polyester resins and polyolefin resins are preferable, and PET and PEN are particularly preferable from the viewpoints of high heat resistance and linear expansion coefficient and low manufacturing cost.

  These resin may be used individually by 1 type, and may be used in combination of 2 or more type.

  The thickness of the 1st board | substrate 11 and the 2nd board | substrate 12 can be suitably set considering the stability at the time of manufacturing the photoelectric conversion element of this embodiment. The thickness of the first substrate 11 and the second substrate 12 is preferably in the range of 5 to 500 μm from the viewpoint that the substrate can be transported even in a vacuum.

  The first substrate 11 and the second substrate 12 are preferably subjected to surface activation treatment for cleaning the surface of the substrate from the viewpoint of adhesion with other layers to be laminated. Examples of such surface activation treatment include corona treatment, plasma treatment, and flame treatment.

  Moreover, when the 1st board | substrate 11 and the 2nd board | substrate 12 are a resin film or a resin sheet, what has one or more thin film layers on the surface is preferable for the improvement of gas-barrier property. Examples of the resin film provided with the thin film layer include a gas barrier laminated film described in JP 2011-73430 A, and a film in which a thin film layer is formed by a plasma CVD method using hexamethyldisiloxane or the like as a film forming gas is preferable. In this case, the thickness of the substrate is more preferably in the range of 50 to 200 μm, and particularly preferably in the range of 50 to 150 μm.

  In addition, although the above-mentioned thin film layer may have the 1st board | substrate 11 and the 2nd board | substrate 12 on one side, it is preferable to have on both surfaces.

  When the first substrate 11 and the second substrate 12 have the above-described thin film layer only on one side of the substrate, the formed thin film layer is formed by the first substrate 11, the second substrate 12, and the sealing portion 18. It is preferable to be arranged so as to face the space. By setting it as such a structure, the gas barrier property of the photoelectric conversion element obtained can be improved.

(First electrode)
The first electrode 13 is formed on the surface of the first substrate 11. The first electrode 13 captures light and functions as an electrode through which charges generated by the photoelectric conversion layer 16 flow in a pair with the second electrode 14. The first electrode 13 is preferably capable of transmitting visible light and infrared light and ultraviolet light near the visible light.

There is no particular limitation on the material of the first electrode 13, _In 2 _{O 3} (indium oxide), SnO ₂ (tin oxide), ZnO (zinc oxide) conductive metal oxides are preferable. In addition, ITO (indium tin oxide), FTO (fluorine-added tin oxide), IZO (indium zinc oxide), ATO (antimony-added tin oxide), AZO (aluminum-added zinc oxide), GZO (gallium-added zinc oxide), etc. Also preferred are metal oxides of the above, zinc oxide doped with indium, and zinc oxide doped with boron.

  The first electrode 13 can also be made of a conductive polymer material. Examples of the polymer material include polythiophene, polypyrrole, polyphenylene vinylene, and polyacetylene polymers.

  The first electrode 13 is preferably a thin film formed using the metal oxide or polymer material. The first electrode 13 may have a single layer structure or a laminated structure such as a two-layer structure.

Although the film thickness of the 1st electrode 13 is not restrict | limited in particular, 0.1-1 micrometer is preferable.
The first electrode 13 may be subjected to a surface treatment such as ozone UV treatment from the viewpoint of adhesion with other layers.

(Hall transport layer)
The hole transport layer 15 is a p-type semiconductor layer that is formed in contact with the first electrode 13 and is electrically connected to the first electrode 13.
The material of the hole transport layer 15 is not particularly limited, and a known organic semiconductor compound can be used. Examples of the organic semiconductor compound include a polymer compound having a triphenylamine skeleton. The hole transport layer 15 can be manufactured by dissolving or dissolving in an organic solvent, coating or printing on the first electrode 13 or a photoelectric conversion layer 16 described later, and heating or baking.

(Second electrode)
The second electrode 14 is formed on the surface of the second substrate 12. There is no particular limitation on the material of the second electrode 14, gold, silver, platinum, aluminum, and calcium metal; ITO, _FTO, SnO 2, conductive metal oxide such as IZO; conductive A polymer material or the like can be used. A thin film formed using these materials is preferably used as the second electrode 14. The method for forming the thin film is not particularly limited, and the thin film can be formed by a conventional method such as vapor deposition or sputtering.
In particular, the second electrode 14 is preferably a metal electrode or a metal oxide electrode.

(Electron transport layer)
The electron transport layer 17 is an n-type semiconductor layer that is formed in contact with the second electrode 14 and is electrically connected to the second electrode 14.

The material for forming the electron transport layer 17 is not particularly limited, and metal oxides such as titanium, tin, zinc, iron, tungsten, zirconium, strontium, indium, cerium, yttrium, lanthanum, vanadium, niobium, and tantalum are used. Can be used. Among these, titanium oxide (TiO ₂ ), strontium titanate (SrTiO ₃ ), zinc oxide (ZnO), tin oxide (SnO ₂ ), tungsten oxide (WO ₃ ), or niobium oxide (Nb ₂ O ₅ ) Titanium oxide, strontium titanate or zinc oxide is more preferable, and titanium oxide or zinc oxide is particularly preferable.
The material for forming the electron transport layer 17 is preferably zinc oxide formed by vacuum deposition or sputtering, and more preferably zinc oxide formed by vacuum deposition.

(Photoelectric conversion layer)
The photoelectric conversion layer 16 is a layer sandwiched between the hole transport layer 15 and the electron transport layer 17 and electrically connected to the hole transport layer 15 and the electron transport layer 17. The photoelectric conversion layer 16 includes particles using a perovskite compound represented by the following formula (1) as a forming material.
ABX ₃ (1)

  In the present specification, the “perovskite compound” refers to a compound having the same crystal structure as the ore “perovskite” (hereinafter referred to as “perovskite structure”) or a compound having a similar perovskite structure.

In formula (1), A is either one or both of a methylammonium ion (CH ₃ NH ₃ ⁺ ) and a formamidinium ion ((NH ₂ ) ₂ CH ⁺ ).

  The methylammonium ion has two atoms, one carbon atom and one nitrogen atom, other than hydrogen. On the other hand, the formamidinium ion has three atoms other than hydrogen, one carbon and two nitrogen. Therefore, when the A site of the crystal having the perovskite structure is substituted with these ions, the volume occupied by the formamidinium ion is larger than that of the methylammonium ion.

  As a result, for example, formamidinium lead perovskite crystal is larger than the methylammonium lead perovskite crystal, and the band gap is reduced. As a result, when a formamidinium lead perovskite crystal is used for the photoelectric conversion layer of the photoelectric conversion element, even longer wavelength infrared rays can be used for power generation, and the amount of current can be increased to increase the conversion efficiency.

  On the other hand, if the band gap becomes too small, the electromotive force during power generation of the photoelectric conversion element becomes too small and the performance may be degraded.

  Therefore, when examining a high-performance photoelectric conversion element, it is preferable to examine the balance between the amount of current and the electromotive force and to form a photoelectric conversion layer having an appropriate band gap that maximizes the conversion efficiency.

  From this viewpoint, in the perovskite crystal constituting the photoelectric conversion layer 16, the methylammonium ion and the formamidinium ion are preferably used in combination. The balance between the amount of current and the electromotive force of the photoelectric conversion element can be adjusted by using methylammonium ion and formamidinium ion in combination and adjusting the ratio of both ions.

When the content of methylammonium ions is increased, the electromotive force can be increased.
Increasing the content of formamidinium ions can increase the amount of current.
In the photoelectric conversion element of this embodiment, by adjusting the content ratio of methylammonium ion and formamidinium ion, the electromotive force and the amount of current are optimized, and the photoelectric conversion element showing the maximum conversion efficiency is adjusted. Can do.

  For example, by using a perovskite crystal in which methylammonium ion: formamidinium ion = 3: 2 is used for the photoelectric conversion layer, a photoelectric conversion element having higher conversion efficiency than that using a perovskite crystal based only on methylammonium ion is obtained. (See Non-Patent Document: Angew. Chem. Int. Ed., Vol. 53, Page 3151-3157 (2014)).

  In Formula (1), B is an ion of either one or both of Pb and Sn.

  In formula (1), X is one or more ions selected from the group consisting of F, Cl, Br and I. X is preferably Br or I.

  Although the film thickness of the photoelectric converting layer 16 is not specifically limited, 50 nm or more is preferable and 100 nm or more is more preferable. The film thickness of the photoelectric conversion layer 16 is preferably 1000 nm or less, more preferably 500 nm or less, and further preferably 300 nm or less. The upper limit value and lower limit value of the film thickness of the photoelectric conversion layer 16 can be arbitrarily combined.

  In the photoelectric conversion layer 16 of the present embodiment, the average particle diameter of particles using the perovskite compound as described above (hereinafter sometimes referred to as “perovskite particles”) is a value measured by the following method. To do.

  About the SEM photograph which image | photographed the perovskite particle | grains, ten straight lines extended in a photograph longitudinal direction are drawn. The 10 straight lines are equally spaced. The magnification of the SEM photograph is appropriately adjusted so that one crystal particle does not overlap with two or more straight lines.

Next, in each straight line, the number of crystal grains overlapping the straight line at the two crystal grain interfaces is measured.
Next, in each straight line, of the intersections between the straight line and the crystal grain interface, the distance from the intersection on the most end side of the straight line to the intersection on the other end side of the straight line is measured.
The average value is obtained by dividing the distance between the obtained intersections by the number of crystal grains obtained previously, and by multiplying the obtained average value by a conversion factor of 1.56, the average crystal grain size of the crystal grains Find the value.

  The same processing was performed on each of the 10 straight lines in one SEM photograph, and the same processing was performed on SEM photographs with four different fields of view, and the average value of 40 crystal grain sizes was obtained. These arithmetic averages are defined as “average particle diameter of perovskite crystal particles” to be obtained.

  When the film thickness of the photoelectric conversion layer 16 is 100 nm or more and 300 nm or less, the average particle diameter of the perovskite particles is preferably 100 nm or more and 300 nm or less.

  When the average particle diameter of the perovskite particles is 100 nm (0.10 μm) or more, the photoelectric conversion layer 16 in which a plurality of crystal grains are stacked does not have excessively high grain boundary resistance, and current generated in the photoelectric conversion layer 16 flows easily. Become. As a result, conversion efficiency is unlikely to decrease.

  Moreover, when the average particle diameter of the perovskite particles is 300 nm (0.30 μm) or less, the resulting perovskite particles are unlikely to be flat particles flattened in the surface direction of the photoelectric conversion layer 16. The flat particles have low crystallinity, and the strength of the photoelectric conversion layer 16 tends to decrease. However, such a problem can be suppressed when the perovskite particles are equal to or less than the upper limit of the average particle diameter.

  In the present embodiment, the perovskite particles of the photoelectric conversion layer 16 have a half-width of the diffraction peak corresponding to the cubic (111) peak of 0.12 ° or more and 0.2. It is less than 14 °.

The “(111) peak” refers to a “diffraction peak with respect to the crystal lattice plane represented by the Miller index (111)”. The same applies to notations using other Miller indices.
The “diffraction peak corresponding to the (111) peak of the cubic crystal” means an incident angle at which the (111) peak of the cubic crystal appears in the X-ray diffraction spectrum having the horizontal axis as the incident angle and the vertical axis as the diffraction intensity. It refers to a diffraction peak that appears at the same incident angle position (corresponding position) as the horizontal axis. In the following description, “diffraction peak corresponding to (111) peak of cubic crystal” may be abbreviated as “corresponding diffraction peak”.

  The half-value width of the diffraction peak is a value measured as follows.

First, an X-ray diffraction spectrum is measured from 10 to 90 degrees at 2θ by the X-ray diffraction method under the following conditions.
(Measurement condition 1)
Powder X-ray analyzer: X'Pert PRO MPD (Spectris Co., Ltd.)
Radiation: Cu-Kα1 line (λ = 0.154050 nm)
X-ray generation voltage: 45 kV
Current: 40 mA
Step size: 0.0020889 degrees
Scan Speed: 0.021989 degrees / second
Time per Step: 12.065 seconds Measurement time: 1 hour 2 minutes 17 seconds

  Next, for the corresponding diffraction peak appearing at around 25 degrees at 2θ, a range of 25 degrees ± 0.75 degrees at 2θ is measured under the following conditions. Other measurement conditions are the same as the measurement condition 1 described above.

(Measurement condition 2)
Time per Step: 300.355 seconds Measurement time: 1 hour 4 minutes 41 seconds

The half width of the corresponding diffraction peak is calculated from the obtained X-ray diffraction spectrum using X-ray diffraction pattern comprehensive analysis software JADE (MDI). The calculation process by the software is performed based on an instruction manual (Jade (Ver. 5) software, instruction manual, Rigaku Corporation) of the software.
In this way, the half width of the corresponding diffraction peak is obtained.

As described above, in the photoelectric conversion element 10 of this embodiment, when evaluating the crystallinity of the perovskite particles, the half width of the corresponding diffraction peak is used among the diffraction peaks of the X-ray diffraction spectrum.
Hereinafter, the “corresponding diffraction peak” will be described.

  Usually, perovskites have a cubic crystal structure at or above the phase transition temperature called the Curie point. When an X-ray diffraction spectrum is measured for a cubic crystal, diffraction peaks for the equivalent crystal lattice plane in the crystal appear at the same position. For example, the crystal lattice plane represented by the Miller index (plane index) (100) is equivalent to the crystal lattice plane represented by (010) and (001), and appears at the same position in the diffraction spectrum.

  It can be evaluated that the diffraction peak measured in this way has higher crystallinity as the crystal has a narrower half width. Note that “high crystallinity” refers to a crystal with few voids in the crystal and little variation in interatomic distance.

However, when the perovskite particle constituting the photoelectric conversion layer 16 is methylammonium iodide perovskite (CH ₃ NH ₃ PbI ₃ ), the crystal structure of the perovskite particle constituting the photoelectric conversion layer 16 has a phase transition from a cubic crystal. Occurs and becomes tetragonal at room temperature. At a lower temperature, a phase transition occurs from a tetragonal crystal at another phase transition temperature, resulting in a tetragonal crystal (orthorhombic crystal). Hereinafter, as an example, it is assumed that the perovskite particles are cubic.

  In the tetragonal system, crystal lattice planes represented by Miller indices (plane indices) (100), (010), and (001) are not equivalent. Therefore, diffraction peaks of these crystal lattice planes corresponding to the (100) peak of the cubic crystal appear at different positions although they are close to each other.

  As a result, the diffraction peaks of the crystal lattice planes represented by (100), (010), and (001) overlap with each other and appear as broad peaks. That is, the “diffraction peak corresponding to the (100) peak of cubic crystal” is a broad peak. Such a broad peak is a result of overlapping a plurality of peaks appearing at shifted positions, and does not indicate that the crystallinity is low.

  On the other hand, the crystal lattice plane represented by the Miller index (plane index) (111) for the cubic crystal is equivalent to the crystal lattice plane represented by (−111), (1-11), etc. Appear in the same position in the spectrum. In addition, the crystal lattice plane represented by the Miller index (plane index) (111) in the tetragonal system is also equivalent to the crystal lattice plane represented by (−111), (1-11), etc. It appears at the same position in the diffraction spectrum.

  Therefore, the half width of the tetragonal (111) peak corresponding to the cubic (111) peak reflects the crystallinity. For example, if the corresponding diffraction peak is a broad peak, it can be determined that the crystal has low crystallinity.

The above discussion also applies when methylammonium iodide lead perovskite (CH ₃ NH ₃ PbI ₃ ) exhibits tetragonal crystals at room temperature.

Similarly, even with methylammonium bromide lead perovskite (CH ₃ NH ₃ PbI ₃ ) that exhibits cubic crystals at room temperature and formamidinium lead iodide that exhibits trigonal crystals at room temperature, the (111) peak is crystalline. Judgment may be made.

  In the photoelectric conversion element 10 of the present embodiment, perovskite particles having a half-value width of 2θ of 0.12 ° or more and less than 0.14 ° at the corresponding diffraction peak are suitable for the photoelectric conversion layer 16 of the photoelectric conversion element 10. It has excellent durability. The half width is preferably 0.12 ° or more and 0.13 ° or less.

  The photoelectric conversion layer 16 may have components other than the perovskite compound described above. For example, it may further contain some impurities or a compound that is not a perovskite structure and has the same or similar composition as the perovskite compound described above.

(Sealing part)
The sealing portion 18 is between the first substrate 11 and the second substrate 12, and surrounds the first electrode 13, the second electrode 14, the hole transport layer 15, the photoelectric conversion layer 16, and the electron transport layer 17. It arrange | positions along the peripheral part of the board | substrate 11 and the 2nd board | substrate 12, and the 1st board | substrate 11 and the 2nd board | substrate 12 are bonded together. Thereby, the photoelectric conversion element 10 includes a first electrode 13, a second electrode 14, and a pair of electrodes in a space formed by the first substrate 11, the second substrate 12, and the sealing portion 18, and It has a structure in which a stacked body including a hole transport layer 15, a photoelectric conversion layer 16, and an electron transport layer 17 is stored.

The sealing part 18 is preferably made of an organic material having a reactive functional group.
Specifically, those having a vinyl group such as vinyltrimethoxysilane and vinyltriethoxysilane as a reactive functional group;
2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycid Having an epoxy group as a reactive functional group such as xylpropyltriethoxysilane;
having a styryl group as a reactive functional group such as p-styryltrimethoxysilane;
Having a methacryl group as a reactive functional group such as 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-methacryloxypropyltriethoxysilane;
Having an acrylic group as a reactive functional group such as 3-acryloxypropyltrimethoxysilane;
N-2- (aminoethyl) -3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) -3-aminopropyltriethoxysilane 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N- (1,3-dimethyl-butylidene) propylamine, N-phenyl-3-aminopropyltrimethoxysilane, N Having an amino group as a reactive functional group, such as-(vinylbenzyl) -2-aminoethyl-3-aminopropyltrimethoxysilane;
Having a ureido group as a reactive functional group such as 3-ureidopropyltriethoxysilane;
Having a mercapto group as a reactive functional group, such as 3-mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane;
Having a sulfide group such as bis (triethoxysilylpropyl) tetrasulfide as a reactive functional group;
Having an isocyanate group as a reactive functional group such as 3-isocyanatopropyltriethoxysilane;
Having a carboxy group as a reactive functional group;
The thing which has an aldehyde group as a reactive functional group is mentioned.

As a photoelectric conversion element of this embodiment, a glass substrate is used as the first substrate 11 and the second substrate 12, an ITO electrode is used as the first electrode 13, a calcium electrode and a silver electrode are used as the second electrode 14, holes [Poly [bis (4-phenyl) (2,4,6-triphenylmethyl) amine]] is used as the transport layer 15, a perovskite compound as described above is used as the photoelectric conversion layer 16, and phenyl is used as the electron transport layer 17. It is preferable to use C ₆₁ butyric acid methyl ester or zinc oxide and use an epoxy compound as the sealing portion 18.

  According to the photoelectric conversion element having the above configuration, a highly durable photoelectric conversion element can be provided.

The technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.
For example, the hole transport layer 15 and the electron transport layer 17 may not be provided separately, but a single transport layer such as PCBM may be substituted.
Moreover, the 1st board | substrate 11, the 2nd board | substrate 12, and the sealing part 18 can also be abbreviate | omitted as needed.
Further, a buffer layer may be provided between the first electrode 13 and the hole transport layer 15. By providing the buffer layer, the first electrode 13 and the hole transport layer 15 can be isolated and electrical contact can be reduced or suppressed. As a material of the buffer layer, a conductive material is preferable, and the above-described metal oxide is more preferable.

[Production Method of Photoelectric Conversion Element]
The manufacturing method of the photoelectric conversion element of this embodiment spin-coats the 1st solution containing B which is a cation, X which is an anion, an organic solvent, and water on one main surface of an electrode, and is BX ₂ layer And a step of spin-coating the BX ₂ layer with a second solution containing A and C which are cations to form an ABX ₃ layer.

A is one or both of a methylammonium ion and a formamidinium ion.
B is one or both of Pb and Sn.
X is one or more ions selected from the group consisting of F, Cl, Br and I.

  A 1st solution contains the said water of more than 0 volume% and 2 volumes or less with respect to the said organic solvent.

Further, in the step of forming the BX ₂ layer, gas is blown from above the electrode toward the one main surface when the electrode rotates.

Further, in the step of forming the ABX ₃ layer, after dropwise the second solution into the BX ₂ layer was dipped the BX ₂ layer to the second solution, start the rotation of the electrode after a predetermined time And spin coat.
Hereinafter, the manufacturing method of a photoelectric conversion element is demonstrated in order.

(First solution)
As for B contained in the 1st solution, only 1 type may contain and 2 or more types may contain. Examples of the B source include BX ₂ which is a metal salt and B (OH) ₂ which is a metal hydroxide.

As for X contained in the 1st solution, only 1 type may contain and 2 or more types may contain. Examples of the X source include BX ₂ which is a metal salt and HX which is an inorganic acid.

The organic solvent contained in the first solution is not particularly limited as long as it can dissolve BX ₂ and other components.
For example, esters such as methyl formate, ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate, pentyl acetate;
ketones such as γ-butyrolactone, N-methyl-2-pyrrolidone, acetone, dimethyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone;
Ethers such as diethyl ether, methyl-tert-butyl ether, diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, 4-methyldioxolane, tetrahydrofuran, methyltetrahydrofuran, anisole, phenetole;
Methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, tert-butanol, 1-pentanol, 2-methyl-2-butanol, methoxypropanol, diacetone alcohol, cyclohexanol, 2-fluoro Alcohols such as ethanol, 2,2,2-trifluoroethanol, 2,2,3,3-tetrafluoro-1-propanol;
Glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, triethylene glycol dimethyl ether;
Amide organic solvents such as N, N-dimethylformamide, acetamide, N, N-dimethylacetamide;
Nitrile organic solvents such as acetonitrile, isobutyronitrile, propionitrile, methoxyacetonitrile;
Carboat organic solvents such as ethylene carbonate and propylene carbonate;
Halogenated hydrocarbon organic solvents such as methylene chloride, dichloromethane, chloroform;
hydrocarbon organic solvents such as n-pentane, cyclohexane, n-hexane, benzene, toluene, xylene;
Examples thereof include dimethyl sulfoxide.

  The organic solvent may have a branched structure or a cyclic structure, may have a plurality of functional groups such as —O—, —CO—, —COO—, and —OH, and the hydrogen atom is fluorine or the like. It may be substituted with a halogen atom.

  As for the organic solvent, only 1 type may contain and 2 or more types may contain.

  The 1st solution may contain components other than B, X mentioned above, and an organic solvent. Examples of other components that may be contained include one or more elements selected from the group consisting of Group 1, Group 2, Group 3, Group 11, Group 12, and Group 13 of the periodic table. Can be mentioned. Among these, Li, Na, Cu, Ag, Au, Mg, Ca, Sr, Ba, Sc, Y, La, Zn, B, Al, Ga, and In are preferable as the component.

(Second solution)
As for A contained in the 2nd solution, only 1 type may contain and 2 types may contain.

  As the organic solvent contained in the second solution, the same solvents as mentioned as the constituents of the first solution can be used. The organic solvent contained in the first solution and the organic solvent contained in the second solution may be the same or different.

  FIG. 2 is a flowchart for explaining a method of manufacturing a photoelectric conversion element according to this embodiment.

(Step S1)
In the method for producing a photoelectric conversion element of this embodiment, first, a first solution is spin-coated on one main surface side of an electrode provided on a substrate (step S1).

  About the composition and density | concentration of a 1st solution, it is good to set and adjust suitably according to the structure of the target photoelectric conversion element 10 (photoelectric conversion layer 16).

  The spin coating conditions (rotation time, rotation speed) may be determined in advance through preliminary experiments.

  When the photoelectric conversion element 10 has the hole transport layer 15 and the electron transport layer 17, the hole transport layer 15 or the electron transport layer 17 is formed on one main surface of the electrode, and then used in Step S1. When the electrode is the first electrode 13, the hole transport layer 15 may be formed on the first electrode 13 and then used in step S <b> 1. Further, when the electrode is the second electrode 14, the electrode transport layer 17 may be formed on the second electrode 14 and then used in step S <b> 1.

(Step S2)
Next, after a predetermined time has elapsed from the start of spin coating, gas spraying is started toward the coating film of the first solution provided on the one main surface side of the electrode (step S2). Steps S1 and S2 correspond to the “step of forming the BX _two layers” in the present invention.

  As the gas, air or inert gas can be used, and air is preferable because it is inexpensive. The blowing of gas toward one main surface of the electrode is referred to as “gas flow” in the following description.

  The gas flow may be performed along the normal direction of one principal surface toward the substantial center of one principal surface of the electrode. Thereby, after the air sprayed toward the electrode hits the coating film, it isotropically diffuses from the center of the coating film toward the peripheral edge. Therefore, gas can be sprayed to the whole coating film without unevenness, and uneven treatment can be reduced.

The gas flow of the first solution to the coating promotes evaporation (removal) of the solvent from the coating. Thereby, the BX ₂ layer is formed on one main surface side of the electrode.

  At this time, as described above, the first solution contains more than 0 volume% and 2 volumes or less of water with respect to the organic solvent. Thereby, the polarity of the solvent of the first solution is increased, and the ionicity of B as a cation or X as an anion is emphasized.

Further, when the removal of the organic solvent proceeds in step S2, the water concentration is relatively increased, and the ionicity of B as a cation or X as an anion is further emphasized. When ionicity is emphasized, crystallization of BX ₂ which is an ionic crystal is promoted.

As a result, in the manufacturing method of the present embodiment, compared to the case where the organic solvent of the first solution does not contain water, the generated BX ₂ crystal grains are smaller when the solvent is removed in step S2.

Further, when the crystal grains become large, there are more opportunities for atomic defects (voids) in the crystal and variations in interatomic distances in the course of crystal grain growth, and the crystal tends to have low crystallinity as a whole. On the other hand, in the manufacturing method of this embodiment, since the crystal grains of BX ₂ produced as described above are small, the crystallinity of the relatively obtained BX ₂ crystal tends to be high.

  That is, in the manufacturing method of the photoelectric conversion element of this embodiment, since the 1st solution contains more than 0 volume% and 2 volume or less of water with respect to the organic solvent, compared with the case where a solvent does not contain water. The crystal grain size becomes smaller.

In addition, since the first solution contains more than 0 volume% and 2 volumes or less of water with respect to the organic solvent, the crystallinity of the BX ₂ crystal is increased, and the half-value width is reduced in the X-ray diffraction spectrum.

Furthermore, in the manufacturing method of a photoelectric conversion device of the present embodiment, by controlling the amount of water contained in the first solution in the above range, it is possible to control the particle size of BX ₂ crystals, the crystallinity. Increasing the amount of water contained in the solvent of the first solution, the crystal grain size of BX ₂ crystals is small and tends to half width is decreased in the X-ray diffraction spectrum of BX ₂ crystals.

(Step S3)
Next, the BX ₂ layer is immersed in the second solution, and after a predetermined time has elapsed, rotation of the electrode is started (spin coating) (step S3). Step S3 corresponds to the “step of forming an ABX ₃ layer” in the present invention.

The second solution is supplied to the BX ₂ layer by being dropped on the BX ₂ layer, for example. The second solution dropped, the immersion of the BX ₂ layers Shimiwatari in BX ₂ layers.

At this time, A, which is a cation contained in the second solution, penetrates into the crystal of BX ₂ to form a crystal structure of the perovskite structure of ABX ₃ .

Here, the inventor believes that in the reaction for forming the perovskite structure, the crystal state of BX ₂ which is a precursor of the perovskite structure contributes to the reactivity, and thus affects the physical properties of the obtained photoelectric conversion layer. It came.

First, in a perovskite solar cell using a perovskite crystal, it is considered that the higher the crystallinity of the perovskite crystal, the higher the conversion efficiency and the better the durability. However, in the reaction for forming the perovskite structure, when A enters into the crystal of BX ₂ , it is considered that the crystal structure of BX ₂ is disturbed and the crystallinity is lowered.

From this idea, in consideration of crystallinity decreased in the reaction to form the perovskite structure, the higher the crystallinity of the BX ₂ is a precursor, it is believed to be higher crystallinity of the resulting perovskite crystal. That is, it is considered that a better photoelectric conversion layer can be obtained when the crystallinity of the precursor BX ₂ is higher. According to this idea, it is preferable that BX ₂ which is a precursor of the perovskite crystal has higher crystallinity.

On the other hand, in the reaction of obtaining A perovskite crystal by contacting A contained in the second solution with BX ₂ as described above, it is considered that the penetration of A into the crystal is inhibited when the crystallinity of BX ₂ is high. . For this reason, when BX ₂ having high crystallinity is used as a precursor, there is a possibility that the reaction in which the perovskite crystal is generated does not easily proceed. As a result, in the obtained photoelectric conversion layer, unreacted BX ₂ may remain and conversion efficiency may be low. According to this idea, if the crystallinity of BX ₂ is high, the physical properties of the photoelectric conversion layer are likely to be low.

As a result of studies by the inventors based on these ideas, the inventors came up with the idea of controlling the immersion time of the second solution according to the crystallinity of BX ₂ which is a precursor of perovskite crystals, and completed the invention.

That is, in the manufacturing method of the present embodiment, when the BX ₂ particles constituting the BX ₂ layer have high crystallinity, the immersion time of the second solution is relatively long, and the BX ₂ particles have low crystallinity. For this, the immersion time of the second solution is relatively shortened. Thereby, the penetration of A into the crystal of BX ₂ can be ensured, and the reaction for forming the perovskite structure can be ensured. The crystallinity of the BX ₂ layers, can be determined from the half width of the X-ray diffraction spectrum of BX ₂ layers.

In addition, for various BX ₂ particles (BX ₂ layers) having different crystallinity, it is preferable to confirm the correspondence relationship between the immersion time of the second solution and the physical properties of the obtained perovskite crystal in advance. Thus, depending on the crystallinity of the resulting BX ₂ particles in step S2, the immersion time of the second solution can be set appropriately.

  For example, when the predetermined time (starting time of gas flow) in step S2 is more than 0 seconds and 3 seconds or less, the immersion time (predetermined time) of the second solution may be 35 seconds or more and 50 seconds or less.

The second solution immersion time (predetermined time) can be determined in a guide crystalline PbI ₂ constituting the PbI ₂ layers. Crystalline PbI ₂ may measure the X-ray diffraction of PbI ₂ layers produced, the peak intensities of each peak is determined from the information of the half-value width, halo such as derived from amorphous each peak. When the crystallinity of PbI ₂ is high, the peak intensity in the X-ray diffraction spectrum is strong, the half width of the peak is narrow, and the halo tends to decrease.

When the crystallinity of PbI ₂ constituting the PbI ₂ layer is high, the immersion time of the second solution may be set longer. In addition, when the crystallinity of PbI ₂ is low, the immersion time of the second solution may be set short.

  After elapse of the immersion time of the second solution, the electrode (substrate) is rotated to perform spin coating. The spin coating conditions (rotation time, rotation speed) may be determined in advance through preliminary experiments.

  After the spin coating, it is preferable to dry as necessary to volatilize the organic solvent contained in the second solution. Drying may be performed at room temperature or by heating.

(Step S4)
Subsequently, the whole is heat-processed (step S4). Step S4 corresponds to the “step of forming the ABX _three layers” in the present invention.

In the heat treatment, for example, it is preferably heated to 50 ° C. or higher and 200 ° C. or lower, and more preferably 100 ° C. or higher and 200 ° C. or lower. By this heat treatment, the formation of a perovskite crystal layer (ABX ₃ layer) is promoted, and a photoelectric conversion layer is suitably formed.

  Then, another layer is laminated | stacked on a photoelectric converting layer, and a photoelectric conversion element can be manufactured by sealing the circumference | surroundings of a photoelectric converting layer.

In the method for manufacturing the photoelectric conversion element of the present embodiment as described above, first, in Steps S1 and S2, a first solution containing a small amount of water is used to form a highly crystalline BX ₂ layer. Next, in steps S3 and S4, according to the BX ₂ layer having high crystallinity, the second solution is immersed in the BX ₂ layer for an appropriate time (predetermined time), so that the perovskite crystal having high crystallinity and high durability ( ABX ₃ ) layer is formed.

  Thereby, according to the manufacturing method of the photoelectric conversion element of this embodiment, a highly durable photoelectric conversion element can be manufactured efficiently.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but it goes without saying that the present invention is not limited to such examples. Various shapes, combinations, and the like of the constituent members shown in the above-described examples are examples, and various modifications can be made based on design requirements and the like without departing from the gist of the present invention.

  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

[Example 1]
After a strip-like ITO film having a thickness of 150 nm and a width of 2 mm was formed on a 25 mm square glass substrate by sputtering, surface treatment was performed using ozone UV. The formed ITO film corresponds to the first electrode.

  Next, it was dissolved in chlorobenzene so that the concentration of [poly [bis (4-phenyl) (2,4,6-triphenylmethyl) amine]] (PTAA) was 0.5% by weight. The resulting solution is filtered through a Teflon (registered trademark) filter having a pore size of 0.5 μm to prepare a coating solution, coated on the entire surface of the glass substrate by spin coating, and heated at 120 ° C. for 10 minutes in the atmosphere. As a result, a hole transport layer was formed.

Next, lead iodide (PbI ₂ ) was weighed to obtain a 0.8 M solution and dissolved in DMF (N, N-dimethylformamide) solvent at 70 ° C. to prepare a solution. Further, 1% by volume of water was added to DMF to prepare a first solution.

  The first solution at 70 ° C. was applied by spin coating over the entire surface of the hole transport layer so as to cover the hole transport layer obtained above. Two seconds after the start of rotation of the substrate, air was blown toward the surface coated with the first solution from above the normal direction of the substrate, and the coating film was dried to obtain a lead iodide layer. The rotation time of the substrate was 20 seconds.

  Next, methylammonium iodide was dissolved in a solvent of dehydrated IPA (2-propanol) to prepare a 45 mg / ml methylammonium iodide solution (second solution).

  The second solution was dropped on the lead iodide layer obtained above, and the lead iodide layer was immersed in the second solution. After leaving still for 35 seconds, spin coating was performed for 20 seconds at a rotation speed of 6000 rpm, and the excess second solution was removed.

  Then, the photoelectric conversion layer was obtained by heating at 100 degreeC for 10 minutes in nitrogen with a dew point of -50 degreeC.

  Then, zinc oxide was vapor-deposited on the photoelectric conversion layer with a vacuum vapor deposition machine to provide a band-shaped zinc oxide layer having a thickness of 15 nm and a width of 2 mm. The formed zinc oxide layer corresponds to the electron transport layer in the present invention.

  Furthermore, gold was vapor-deposited on the zinc oxide layer, and a strip-shaped gold electrode having a thickness of 100 nm and a width of 2 mm was provided. The formed gold electrode corresponds to the second electrode in the present invention.

  The zinc oxide layer and the gold electrode were formed so as to be orthogonal to the ITO film in the visual field from the normal direction of the glass substrate. In the same field of view, the gold electrode was formed so as to overlap the zinc oxide layer.

The photoelectric conversion element of Example 1 was produced as described above. The degree of vacuum during the deposition was 1 to 9 × 10 ⁻⁵ Pa in all cases.

  A glass substrate (hereinafter referred to as a glass cover) provided with a recess was prepared, and the photoelectric conversion element formed on the glass substrate was covered with a glass cover and sealed in nitrogen having a dew point of −50 ° C. Specifically, the glass cover is placed so that the photoelectric conversion element is disposed in the recess of the glass cover, and the glass substrate provided with the photoelectric conversion element and the glass cover are sealed with a UV curable resin. did. This produced the sealing element for conversion efficiency measurement.

(Examples 2-7, Comparative Examples 1-9)
Except that the time from the start of rotation of the substrate to the spray of air during the spin coating of the first solution and the time from the start of spin coating after the lead iodide layer was immersed in the second solution were changed. In the same manner as in Example 1, photoelectric conversion elements of Examples 2 to 7 and Comparative Examples 1 to 9 were manufactured, and sealing elements were manufactured.

  About each obtained photoelectric conversion element, it evaluated as follows.

[Conversion efficiency]
The photoelectric conversion elements obtained in Examples and Comparative Examples are generated by irradiating with constant light using a solar simulator (product name: OTENTO-SUNII: AM1.5G filter, irradiance: 100 mW / cm ² , manufactured by Spectrometer). Current and voltage were measured.

In the embodiment, the ratio of the areas converted maximum output for irradiance 100 mW / cm ² (maximum output in terms of 1 cm ²⁾ (percentage:%) and the conversion efficiency. The maximum output is a value obtained by the product of maximum current × maximum voltage.

[Light resistance test]
The light resistance test was conducted as follows.
Using a xenon weather meter ("Atlas Ci4000" manufactured by Toyo Seiki Seisakusho Co., Ltd.), the light of the xenon lamp, which is pseudo-sunlight, under the conditions of an irradiance of 100 mW / cm ² , a temperature of 65 ° C, and a relative humidity of 50%, The sealing elements obtained in Examples and Comparative Examples were irradiated for 2 weeks, and then the conversion efficiency was evaluated.
The conversion efficiency after irradiation for 2 weeks is shown in Table 1 as “durability evaluation” (unit:%).

[X-ray diffraction spectrum of perovskite crystal particles]
The photoelectric conversion element was taken out from the sealing element that had been subjected to the light resistance test, and the X-ray diffraction spectrum was measured so that the X-ray directly hit the photoelectric conversion layer as it was without decomposing the photoelectric conversion element.

The X-ray diffraction spectrum was measured at 2θ from 10 to 90 degrees by the X-ray diffraction method under the following conditions.
(Measurement condition 1)
Powder X-ray analyzer: X'Pert PRO MPD (Spectris Co., Ltd.)
Radiation: Cu-Kα1 line (λ = 0.154050 nm)
X-ray generation voltage: 45 kV
Current: 40 mA
Step size: 0.0020889 degrees
Scan Speed: 0.021989 degrees / second
Time per Step: 12.065 seconds Measurement time: 1 hour 2 minutes 17 seconds

  As a result of the measurement, it was confirmed that the corresponding diffraction peak appeared at around 25 degrees at 2θ.

  Next, the confirmed corresponding diffraction peak was measured in the range of 25 ° ± 0.75 ° at 2θ under the following conditions. In this range, background measurement and baseline setting were performed. Other measurement conditions were the same as the measurement condition 1 described above.

(Measurement condition 2)
Time per Step: 300.355 seconds Measurement time: 1 hour 4 minutes 41 seconds

  The half width of the diffraction peak was calculated from the obtained X-ray diffraction spectrum using X-ray diffraction pattern comprehensive analysis software JADE (MDI). The calculation process by the software was performed based on the instruction manual (Jade (Ver. 5) software, instruction manual, Rigaku Corporation) of the software.

[Average particle size of perovskite crystal particles]
The photoelectric conversion element was taken out from the sealing element that had been subjected to the light resistance test, and the photoelectric conversion layer was subjected to gold sputtering without decomposing the photoelectric conversion element, and the SEM observation of the photoelectric conversion layer was performed. In the SEM observation, adjustment was made so that the electron beam directly hits the photoelectric conversion layer of the photoelectric conversion element.

  The average particle diameter of the crystal particles was measured by the following method based on the photographed SEM photograph.

  First, for the SEM photograph, 10 straight lines extending in the longitudinal direction of the photograph were drawn. Ten straight lines were equally spaced. The magnification of the SEM photograph was adjusted as appropriate so that one crystal particle had a size that did not overlap two or more straight lines.

Subsequently, in each straight line, the number of crystal grains overlapping with the straight line at two crystal grain interfaces was measured.
Next, in each straight line, among the intersections between the straight line and the crystal grain interface, the distance from the intersection on the most end side of the straight line to the intersection on the most other end side of the straight line was measured.
The average value is obtained by dividing the distance between the obtained intersections by the number of crystal grains obtained previously, and by multiplying the obtained average value by a conversion factor of 1.56, the average crystal grain size of the crystal grains The value was determined.

  The same processing was performed on each of the 10 straight lines in one SEM photograph, and the same processing was performed on SEM photographs with four different fields of view, and the average value of 40 crystal grain sizes was obtained. These arithmetic averages were defined as “average particle diameter of perovskite crystal particles” to be obtained.

  The results of Examples and Comparative Examples are shown in Table 1. In Table 1, “Time from start of substrate rotation to air blowing at the time of spin coating of the first solution” is set as “Time 1”, and “Spin coating is started after the lead iodide layer is immersed in the second solution” “Time until” is described as “Time 2”.

  FIG. 3 is a scatter diagram showing the relationship between the half-value width of a diffraction peak (corresponding diffraction peak) corresponding to a cubic (111) peak and the conversion efficiency of the obtained photoelectric conversion element. In FIG. 2, the horizontal axis indicates the half width (unit: °), and the vertical axis indicates the conversion efficiency (%).

  As shown in the figure, in the X-ray diffraction spectrum of the perovskite particles, the half-value width of the corresponding diffraction peak at 2θ is 0.12 ° or more and less than 0.14 ° is more durable than the half-value width outside the range. It was confirmed that the property is high.

  From the above results, it was found that the present invention is useful.

  DESCRIPTION OF SYMBOLS 10 ... Photoelectric conversion element, 11 ... 1st board | substrate, 12 ... 2nd board | substrate, 13 ... 1st electrode, 14 ... 2nd electrode, 15 ... Hole transport layer, 16 ... Photoelectric conversion layer, 17 ... Electron transport layer,

Claims (6)

A first electrode;
A second electrode;
A photoelectric conversion layer sandwiched between the first electrode and the second electrode,
The photoelectric conversion layer includes particles having a perovskite compound represented by ABX ₃ as a forming material,
The average particle diameter of the particles is 0.10 μm or more and 0.30 μm or less,
In the X-ray diffraction spectrum of the particles, a half-width of a diffraction peak corresponding to a cubic (111) peak is 2θ of 0.12 ° or more and less than 0.14 °.
(In the formula, A is one or both of methylammonium ion and formamidinium ion.
B is one or both of Pb and Sn.
X is one or more ions selected from the group consisting of F, Cl, Br and I. )   The photoelectric conversion element according to claim 1, further comprising an electron transport layer between the first electrode and the photoelectric conversion layer.   The photoelectric conversion element according to claim 2, wherein the electron transport layer is formed of an inorganic material.   The photoelectric conversion element according to claim 3, wherein the electron transport layer is made of a conductive oxide.   The photoelectric conversion element according to claim 4, wherein the electron transport layer is made of zinc oxide. A step of spin-coating a first solution containing B as a cation, X as an anion, an organic solvent and water on one principal surface side of the electrode to form a BX ₂ layer;
A step of spin-coating a second solution containing cation A and X on the BX ₂ layer to form an ABX ₃ layer;
A is one or both of methylammonium ion and formamidinium ion,
B is an ion of either one or both of Pb and Sn;
X is one or more ions selected from the group consisting of F, Cl, Br and I;
The first solution includes more than 0 volume% and 2 volumes or less of the water with respect to the organic solvent,
In the step of forming the BX _two layers, a gas is blown from above the electrode toward the one main surface during rotation of the electrode,
Wherein in the step of forming the the ABX ₃ layers, after dropwise the second solution into the BX ₂ layer was dipped the BX ₂ layer to the second solution, the crystalline state of BX ₂ particles constituting the BX ₂ layers After the elapse of a predetermined time determined based on the above, a method for manufacturing a photoelectric conversion element, in which rotation of the electrode is started and spin coating is performed.

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