Photoelectric conversion material and photoelectric conversion element using the same

Abstract

A photoelectric conversion material according to the present disclosure contains a crystal phase including A, B, X, and I. Here, A is a monovalent cation and includes a monovalent organic cation. B is a divalent cation and includes Sn. X is at least one element selected from the group consisting of F, Cl, and Br. The total molar ratio of X and I to B is 2.80-3.25 inclusive, and the molar ratio of B to A is more than 1.00 but not more than 1.50. A photoelectric conversion element 100 according to the present disclosure comprises a first electrode 2, a photoelectric conversion layer 4, and a second electrode 6, wherein the photoelectric conversion layer 4 includes the photoelectric conversion material according to the present disclosure.

Description

Technical Field

[0001] The present disclosure relates to a photoelectric conversion material and a photoelectric conversion device using the same.

Background Art

[0002] Non-Patent Document 1 discloses a solar cell using CsSnI 2 added with SnF 3 . Non-Patent Document 2 discloses a structure having stability for a Sn-based perovskite compound containing I.

Prior Art Documents

Non-Patent Documents

[0003]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Non-Patent Document 4

[0004] An object of the present disclosure is to improve the photoelectric conversion efficiency of a photoelectric conversion material containing Sn. MEANS FOR SOLVING THE PROBLEM

[0005] The photoelectric conversion material of the present disclosure contains a crystal phase containing A, B, X, and I, where A is a monovalent cation and contains a monovalent inorganic cation, B is a divalent cation and contains Sn, X is at least one selected from the group consisting of F, Cl, and Br, The total molar ratio of X and I to B is 2.80 or more and 3.25 or less, The molar ratio of B to A is more than 1.00 and 1.50 or less. EFFECTS OF THE INVENTION

[0006] The present disclosure improves the photoelectric conversion efficiency of a photoelectric conversion material containing Sn. BRIEF DESCRIPTION OF THE DRAWINGS

[0007]

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Mode for Carrying Out the Invention

[0008] [First Embodiment] The photoelectric conversion material of the first embodiment contains a crystal phase including A, B, X, and I. Here, A is a monovalent cation and includes a monovalent inorganic cation. B is a divalent cation and includes Sn. X is at least one selected from the group consisting of F, Cl, and Br. The total molar ratio of X and I to B is 2.80 or more and 3.25 or less. The molar ratio of B to A is more than 1.00 and 1.50 or less.

[0009] According to the above configuration, the photoelectric conversion efficiency of the photoelectric conversion material can be improved.

[0010] In order to improve the conversion efficiency of the photoelectric conversion material, the molar ratio of B to A may be more than 1.00 and less than 1.30.

[0011] In order to improve the conversion efficiency of the photoelectric conversion material, the molar ratio of X to I may be 0.03 or more and 0.19 or less.

[0012] In the X-ray diffraction pattern obtained by X-ray structure analysis using the Cu-Kα line of the crystal phase contained in the photoelectric conversion material of the first embodiment, peaks may exist in the range of diffraction angles 2θ of 25.14° or more and 25.17° or less, and 29.13° or more and 29.17° or less.

[0013] In the photoelectric conversion material of the first embodiment, the crystal phase may have a perovskite structure. That is, the photoelectric conversion material of the first embodiment may be a perovskite compound.

[0014] The perovskite compound means a perovskite crystal structure represented by the chemical formula ABX’ 3 and a structure having a crystal similar thereto. Here, A is a monovalent cation, B is a divalent cation, and X’ is a halogen anion.

[0015] In the photoelectric conversion material of the first embodiment, the monovalent cation represented by A includes a monovalent inorganic cation. Examples of the monovalent inorganic cation are alkali metal cations. Examples of the alkali metal cation are potassium cation (K + ), cesium cation (Cs + ), or rubidium cation (Rb + ).

[0016] The monovalent cation represented by A may further include a monovalent organic cation. That is, in the photoelectric conversion material of the first embodiment, A may include a monovalent inorganic cation and a monovalent organic cation. In this case, the ratio of the amount of substance of the monovalent inorganic cation to the total amount of substance of the monovalent inorganic cation and the monovalent organic cation may be, for example, 5 mol% or more and 30 mol% or less.

[0017] In the photoelectric conversion material of the first embodiment, A may be a monovalent inorganic cation. That is, 100 mol% of the monovalent cation represented by A may be a monovalent inorganic cation.

[0018] In the photoelectric conversion material of the first embodiment, A may contain Cs. A may contain 8 mol% or more of Cs. A may be Cs.

[0019] Examples of the monovalent organic cation are methylammonium cation (that is, CH 3 NH 3 + (hereinafter, CH 3 NH 3 is referred to as "MA").), formamidinium cation (that is, NH 2 CHNH 2 + (hereinafter, NH 2 CHNH 2 is referred to as "FA").), phenylethylammonium cation (that is, C 6 H 5 C 2 H 4 NH 3 +) or a guanidinium cation (i.e., CH 6 N 3 + ).

[0020] Examples of the divalent cation represented by B are a lead cation (Pb 2+ ), a tin cation (Sn 2+ ), or a germanium cation (Ge 2+ ). In the photoelectric conversion material of the first embodiment, B contains at least Sn. B may be Sn.

[0021] Both A and B may contain a plurality of types of cations.

[0022] In the photoelectric conversion material of the first embodiment, X may contain at least one selected from the group consisting of F and Cl. X may be F or Cl.

[0023] When A in the photoelectric conversion material of the first embodiment contains a monovalent inorganic cation, the photoelectric conversion material of the first embodiment can stabilize Sn as divalent by substituting a part of I bonded to Sn with F, Cl, or Br while maintaining thermodynamic stability. Here, CsSnI 3 will be taken as an example for a more detailed explanation. FIG. 1 is a diagram showing the relationship between the value of the Goldschmidt tolerance factor and the ionic radius of the A site for CsSnI 3 , FASnI 3 , and MASnI 3 . Referring to Non-Patent Document 3, the ionic diameter of I - is 2.20 Å, and the ionic diameter of Cs + is 1.67 Å. Also, the ionic diameter of Sn 2+ calculated from the results measured by the present inventor using XRD is 0.864 Å. Using these values, the Goldschmidt tolerance of CsSnI 3 is 0.8932. CsSnI 3By replacing part of I with F, the value of the Goldschmidt tolerance factor can be brought closer to the ideal range of 0.9 to 1, improving the thermodynamic stability while stabilizing Sn in the divalent state. On the other hand, when the A-site is an organic cation such as FA + or MA + according to Non-Patent Document 4, the ionic radius of FA + is 2.53 Å, and that of MA + is 2.17 Å. The organic cation at the A-site is larger than Sn at the B-site, and the Goldschmidt tolerance factor exceeds 1. Specifically, the Tolerance Factor of FASnI 3 is 1.092, and that of MASnI 3 is 1.009. Therefore, when the A-site is an organic cation such as FA + or MA + and part of I is replaced by F, the Goldschmidt Tolerance factor increases and becomes unstable, so the replacement of I with F is less likely to occur. Also, SnI 2 is likely to oxidize in the air and Sn becomes tetravalent, but SnF 2 is stable in the air and Sn is stable in the divalent state. Therefore, it is considered that the oxidation resistance is also improved by replacing part of I in CsSnI 3 with F.

[0024] The photoelectric conversion material of the first embodiment can be manufactured, for example, by the following method.

[0025] First, a precursor solution of the photoelectric conversion material of the first embodiment is prepared. The precursor solution can be prepared by dissolving the raw materials of the photoelectric conversion material in a solvent having a relatively high boiling point, for example. The raw materials used for the preparation of the precursor solution of the photoelectric conversion material of the first embodiment are, for example, compounds containing A and I such as CsI, compounds containing B and I such as SnI 2 , and SnF 2It is a compound containing B and X as described above. As an example of the solvent, for instance, a solvent containing DMSO (dimethyl sulfoxide (boiling point 189 °C)) having a relatively high boiling point can be mentioned. The solvent may be a mixed solvent containing a plurality of solvents or may be composed of one type of solvent. The precursor solution may be prepared, for example, by first preparing a first precursor solution containing a compound containing A and I, a compound containing B and I, and a solvent, and a second precursor solution containing a compound containing B and X and a solvent, and then mixing the first precursor solution and the second precursor solution. Next, the prepared precursor solution is applied to a substrate by a coating method such as spin coating, and the obtained coating film is allowed to stand for a predetermined time to grow crystal nuclei in the coating film. Thereafter, the coating film is fired at a temperature relatively lower than the boiling point of the solvent. For example, when a mixed solvent of DMF (dimethylformamide) and DMSO (volume ratio 1:1) is used, for instance, after growing crystal nuclei in the coating film at room temperature, the coating film may be fired at a temperature of about 120 °C.

[0026] On the other hand, SnF described in Non-Patent Document 1 explained in the [Background Art] section 2 added CsSnI 3 is a precursor solution containing CsSnI 3 , SnF 2 , and DMSO as a solvent, which is spin-coated, and the obtained coating film is slowly crystallized at 70 °C. In the optoelectronic conversion material of Non-Patent Document 1 produced in such a manner, no peak shift in XRD is observed even when the concentration of SnF 2 in the precursor solution is increased. From this, it is shown that in Non-Patent Document 1, F - does not replace I - . That is, the optoelectronic conversion material described in Non-Patent Document 1 does not contain a crystal phase containing A, B, X, and I.

[0027] [Second Embodiment] Hereinafter, the optoelectronic conversion element of the second embodiment will be described. Matters described in the first embodiment may be omitted as appropriate.

[0028] The photoelectric conversion element of the second embodiment includes a first electrode, a photoelectric conversion layer, and a second electrode. The photoelectric conversion layer contains the photoelectric conversion material of the first embodiment. Therefore, the photoelectric conversion element of the second embodiment has high photoelectric conversion efficiency.

[0029] FIG. 2 is a cross-sectional view showing a schematic configuration of the photoelectric conversion element 100 of the second embodiment.

[0030] The photoelectric conversion element 100 according to the second embodiment includes, for example, a substrate 1, a first electrode 2, an electron transport layer 3, a photoelectric conversion layer 4, a hole transport layer 5, and a second electrode 6 in this order. Note that the substrate 1, the electron transport layer 3, and the hole transport layer 5 may not be provided.

[0031] The photoelectric conversion layer 4 contains the photoelectric conversion material of the first embodiment.

[0032] When the photoelectric conversion element 100 is irradiated with light, the photoelectric conversion layer 4 absorbs the light and separates the charges into electrons and holes. The electrons generated by this charge separation move through the electron transport layer 3 to the first electrode 2. On the other hand, the holes generated in the photoelectric conversion layer 4 move to the second electrode 6 through the hole transport layer 5. Thereby, the photoelectric conversion element 100 can extract a current from the first electrode 2 as the negative electrode and the second electrode 6 as the positive electrode.

[0033] Hereinafter, each component of the photoelectric conversion element will be specifically described.

[0034] (Substrate 1) The substrate 1 is an incidental component. The substrate 1 serves to hold each layer of the photoelectric conversion element 100. The substrate 1 can be formed of a transparent material. As the substrate 1, for example, a glass substrate or a plastic substrate can be used. The plastic substrate may be, for example, a plastic film.

[0035] When the second electrode 6 has translucency, the substrate 1 may be formed of a material that does not have translucency. As such a material, metals, ceramics, or resin materials with low translucency can be used.

[0036] When the first electrode 2 has sufficient strength, each layer can be held by the first electrode 2, so the substrate 1 may not be provided.

[0037] (The first electrode 2) The first electrode 2 has conductivity.

[0038] The first electrode 2 has translucency. For example, it transmits light from the visible region to the near-infrared region.

[0039] The first electrode 2 is composed of, for example, a material that is transparent and has conductivity. Examples of such materials are metal oxides or metal nitrides. Examples of such materials are (i) titanium oxide doped with at least one selected from the group consisting of lithium, magnesium, niobium, and fluorine, (ii) gallium oxide doped with at least one selected from the group consisting of tin and silicon, (iii) gallium nitride doped with at least one selected from the group consisting of silicon and oxygen, (iv) tin oxide doped with at least one selected from the group consisting of antimony and fluorine, (v) zinc oxide doped with at least one selected from the group consisting of boron, aluminum, gallium, and indium, (vi) indium-tin composite oxide, or (vii) composites thereof, are.

[0040] The first electrode 2 may be formed by providing a pattern through which light can pass. Examples of the pattern through which light can pass include a linear shape, a wavy shape, a lattice shape, or a punching metal-like pattern in which a large number of fine through-holes are arranged regularly or irregularly. When the first electrode 2 has these patterns, light can pass through the portions where the electrode material does not exist. Therefore, by providing a pattern through which light can pass, a non-transparent material can be used. Examples of non-transparent electrode materials include platinum, gold, silver, copper, aluminum, rhodium, indium, titanium, iron, nickel, tin, zinc, or an alloy containing any of these. A carbon material having conductivity may be used as the non-transparent electrode material.

[0041] The light transmissivity of the first electrode 2 does not necessarily have to be realized by the pattern through which light passes as described above. For example, the first electrode 2 may be formed of a thin-film metal formed with a thickness of about 10 nm. Such a thin-film metal is, for example, platinum, gold, silver, copper, aluminum, rhodium, indium, titanium, iron, nickel, tin, zinc, or an alloy containing any of these. Instead of these metal materials, a carbon material having conductivity may be used.

[0042] When the photoelectric conversion element 100 does not include the electron transport layer 3, the first electrode 2 has a blocking property against holes from the photoelectric conversion layer 4. In this case, the first electrode 2 is not in ohmic contact with the photoelectric conversion layer 4. Furthermore, the blocking property against holes from the photoelectric conversion layer 4 means a property of allowing only electrons generated in the photoelectric conversion layer 4 to pass through and not allowing holes to pass through. The Fermi energy of a material having such a property is higher than the energy at the upper end of the valence band of the photoelectric conversion layer 4. The Fermi energy of a material having such a property may also be higher than the Fermi energy of the photoelectric conversion layer 4. A specific material includes aluminum.

[0043] When the photoelectric conversion element 100 includes the electron transport layer 3, the first electrode 2 does not necessarily have to have a blocking property against holes from the photoelectric conversion layer 4. In this case, the first electrode 2 can be composed of a material capable of forming an ohmic contact with the photoelectric conversion layer 4. In this case, the first electrode 2 may or may not be in ohmic contact with the photoelectric conversion layer 4.

[0044] The light transmittance of the first electrode 2 may be, for example, 50% or more, or may be 80% or more. The wavelength of the light to be transmitted by the first electrode 2 depends on the absorption wavelength of the photoelectric conversion layer 4.

[0045] The thickness of the first electrode 2 may be, for example, 1 nm or more and 1000 nm or less.

[0046] (Electron transport layer 3) The electron transport layer 3 contains a semiconductor. The electron transport layer 3 may be formed of a semiconductor having a band gap of 3.0 eV or more. Thereby, visible light and infrared light can be transmitted to the photoelectric conversion layer 4. Examples of the semiconductor are inorganic n-type semiconductors.

[0047] Examples of inorganic n-type semiconductors are metal oxides, metal nitrides, or perovskite-type oxides. Examples of metal oxides are oxides of Cd, Zn, In, Pb, Mo, W, Sb, Bi, Cu, Hg, Ti, Ag, Mn, Fe, V, Sn, Zr, Sr, Ga, Si, or Cr. The metal oxide is, for example, TiO 2 or SnO 2 is. The metal nitride is, for example, GaN. The perovskite-type oxide is, for example, SrTiO 3 or CaTiO 3 is.

[0048] In particular, when effectively transmitting ultraviolet light to the photoelectric conversion layer 4, the electron transport layer 3 may use a semiconductor having a band gap of 6.0 eV or more. Examples of such semiconductors include halides of alkali metals or alkaline earth metals such as lithium fluoride and calcium fluoride, alkali metal oxides such as magnesium oxide, or silicon dioxide. In this case, in order to ensure the electron transport property of the electron transport layer 3, the electron transport layer 3 may have a thickness of, for example, 10 nm or less.

[0049] The electron transport layer 3 may include a plurality of layers made of different materials from each other.

[0050] (Photoelectric conversion layer 4) The photoelectric conversion layer 4 includes the photoelectric conversion material of the first embodiment.

[0051] The photoelectric conversion layer 4 may mainly include the photoelectric conversion material of the first embodiment. Here, "the photoelectric conversion layer 4 mainly includes the photoelectric conversion material of the first embodiment" means that the photoelectric conversion layer 4 contains 50% by mass or more of the photoelectric conversion material of the first embodiment. The photoelectric conversion layer 4 may contain 70% by mass or more of the photoelectric conversion material of the first embodiment. The photoelectric conversion layer 4 may contain 90% by mass or more of the photoelectric conversion material of the first embodiment. The photoelectric conversion layer 4 may be made of the photoelectric conversion material of the first embodiment. The photoelectric conversion layer 4 only needs to contain the photoelectric conversion material of the first embodiment and may contain defects or impurities.

[0052] The photoelectric conversion layer 4 may also contain a photoelectric conversion material different from the photoelectric conversion material of the first embodiment.

[0053] The thickness of the photoelectric conversion layer 4 is, for example, 50 nm or more and 10 μm or less.

[0054] The photoelectric conversion layer 4 can be formed by a coating method using a solution, a printing method, or a vapor deposition method. Examples of the coating method include a doctor blade method, a bar coating method, a spray method, a dip coating method, an inkjet method, a slit coating method (i.e., a die coating method), or a spin coating method.

[0055] (Hole transport layer 5) The hole transport layer 5 contains a hole transport material. The hole transport material is a material that transports holes. The hole transport material is, for example, an organic semiconductor or an inorganic semiconductor.

[0056] Examples of organic semiconductors are triphenylamine, triallylamine, phenylbenzidine, phenylene vinylene, tetrathiafulvalene, vinyl naphthalene, vinyl carbazole, thiophene, aniline, pyrrole, carbazole, triphenylene, fluorene, azulene, pyrene, pentacene, perylene, acridine, or phthalocyanine.

[0057] Examples of typical organic semiconductors used as hole transport materials are 2,2′,7,7′-tetrakis-(N,N-di-p-methoxyphenylamine)9,9′-spirobifluorene, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (hereinafter also referred to as "PTAA"), poly(3-hexylthiophene-2,5-diyl), poly(3,4-ethylenedioxythiophene), or copper phthalocyanine.

[0058] The inorganic semiconductor used as the hole transport material is a p-type semiconductor. Examples of inorganic semiconductors are Cu 2 O, CuGaO 2 , CuSCN, CuI, NiO x , MoO x , V 2 O 5 , or a carbon material such as graphene oxide. Here, x satisfies x > 0.

[0059] The hole transport layer 5 may include a plurality of layers made of different materials. For example, by laminating a plurality of layers such that the ionization potential of the hole transport layer 5 becomes sequentially smaller with respect to the ionization potential of the photoelectric conversion layer 4, the hole transport characteristics are improved.

[0060] The thickness of the hole transport layer 5 may be 1 nm or more and 1000 nm or less, or may be 10 nm or more and 50 nm or less. Thereby, sufficient hole transport characteristics can be exhibited. Therefore, the low resistance of the photoelectric conversion element 100 can be maintained, and high photoelectric conversion efficiency can be realized.

[0061] The hole transport layer 5 is formed, for example, by a coating method, a printing method, or a vapor deposition method. This is the same as the photoelectric conversion layer 4. Examples of the coating method include the doctor blade method, the bar coating method, the spray method, the dip coating method, the inkjet method, the slit coating method (i.e., the die coating method), or the spin coating method. An example of the printing method is the screen printing method. If necessary, a plurality of materials may be mixed to produce the hole transport layer 5, and it may be pressurized or fired. When the material of the hole transport layer 5 is an organic low molecular weight substance or an inorganic semiconductor, it is also possible to produce the hole transport layer 5 by a vacuum vapor deposition method.

[0062] The hole transport layer 5 may contain not only a hole transport material but also an additive in order to enhance conductivity. Examples of the additive are a supporting electrolyte, a solvent, or a dopant. The supporting electrolyte and the solvent have the effect of stabilizing holes in the hole transport layer 5. The dopant has the effect of increasing the number of holes in the hole transport layer 5.

[0063] Examples of the supporting electrolyte are ammonium salts, alkaline earth metal salts, or transition metal salts. Examples of ammonium salts are tetrabutylammonium perchlorate, tetraethylammonium hexafluorophosphate, imidazolium salts, or pyridinium salts. Examples of alkali metal salts are lithium perchlorate or potassium tetrafluoroborate. Examples of alkaline earth metal salts are lithium bis(trifluoromethanesulfonyl)imide or calcium(II) bis(trifluoromethanesulfonyl)imide. Examples of transition metal salts are zinc(II) bis(trifluoromethanesulfonyl)imide or tris[4-tert-butyl-2-(1H-pyrazol-1-yl)pyridine]cobalt(III) tris(trifluoromethanesulfonyl)imide.

[0064] Examples of the dopant are fluorine-containing aromatic boron compounds. An example of the fluorine-containing aromatic boron compound is tris(pentafluorophenyl)borane.

[0065] The solvent contained in the hole transport layer 5 may have excellent ionic conductivity. The solvent may be an aqueous solvent or an organic solvent. In order to better stabilize the solute, the solvent contained in the hole transport layer 5 may be an organic solvent. Examples of the organic solvent are heterocyclic compound solvents such as tert-butylpyridine, pyridine, and n-methylpyrrolidone.

[0066] An ionic liquid may be used as the solvent. The ionic liquid may be used alone or mixed with other solvents. The ionic liquid is desirable in that it has low volatility and high flame retardancy.

[0067] Examples of the ionic liquid are imidazolium-based, pyridine-based, alicyclic amine-based, aliphatic amine-based, or azonium amine-based such as 1-ethyl-3-methylimidazolium tetracyanoborate.

[0068] (Second electrode 6) The second electrode 6 has conductivity.

[0069] When the photoelectric conversion element 100 does not include the hole transport layer 5, the second electrode 6 has a blocking property against electrons from the photoelectric conversion layer 4. In this case, the second electrode 6 is not in ohmic contact with the photoelectric conversion layer 4. The blocking property against electrons from the photoelectric conversion layer 4 means the property of allowing only holes generated in the photoelectric conversion layer 4 to pass through and not allowing electrons to pass through. The Fermi energy of a material having such a property is lower than the energy at the lower end of the conduction band of the photoelectric conversion layer 4. The Fermi energy of a material having such a property may also be lower than the Fermi energy of the photoelectric conversion layer 4. Specific materials include carbon materials such as platinum, gold, or graphene.

[0070] When the photoelectric conversion element 100 includes the hole transport layer 5, the second electrode 6 does not necessarily have blocking property against electrons from the photoelectric conversion layer 4. In this case, the second electrode 6 can be composed of a material capable of forming an ohmic contact with the photoelectric conversion layer 4. Thereby, the second electrode 6 can be formed to have translucency.

[0071] Among the first electrode 2 and the second electrode 6, it is sufficient that the electrode on the light incident side has translucency. Therefore, one of the first electrode 2 and the second electrode 6 does not necessarily have translucency. That is, one of the first electrode 2 and the second electrode 6 does not necessarily use a translucent material, nor does it necessarily have a pattern including an opening portion for transmitting light.

[0072] (porous layer) The porous layer is formed on the electron transport layer 3, for example, by a coating method. When the photoelectric conversion element 100 does not include the electron transport layer 3, it is formed on the first electrode 2.

[0073] The pore structure introduced by the porous layer serves as a base when forming the photoelectric conversion layer 4. The porous layer does not inhibit the light absorption of the photoelectric conversion layer 4 and the electron transfer from the photoelectric conversion layer 4 to the electron transport layer 3.

[0074] The porous layer includes a porous body.

[0075] The porous body is formed, for example, by a continuous connection of insulating or semiconductor particles. Examples of insulating particles are aluminum oxide particles or silicon oxide particles. Examples of semiconductor particles are inorganic semiconductor particles. Examples of inorganic semiconductors are metal oxides, perovskite oxides of metal elements, sulfides of metal elements, or metal chalcogenides. Examples of metal oxides are oxides of Cd, Zn, In, Pb, Mo, W, Sb, Bi, Cu, Hg, Ti, Ag, Mn, Fe, V, Sn, Zr, Sr, Ga, Si, or Cr. The metal oxide is, for example, TiO 2 is. Examples of perovskite oxides of metal elements are SrTiO 3 or CaTiO 3It is. Examples of sulfides of metal elements are CdS, ZnS, In 2 S 3 、PbS, Mo 2 S, WS 2 、Sb 2 S 3 、Bi 2 S 3 、ZnCdS 2 、or Cu 2 S. Examples of metal chalcogenides are CsSe, In 2 Se 3 、WSe 2 、HgS, PbSe, or CdTe.

[0076] The thickness of the porous layer may be 0.01 μm or more and 10 μm or less, or may be 0.05 μm or more and 1 μm or less.

[0077] Regarding the surface roughness of the porous layer, the surface roughness coefficient given by the effective area / projected area may be 10 or more, or may be 100 or more. The projected area is the area of the shadow formed behind when the object is illuminated with light from the front. The effective area is the actual surface area of the object. The effective area can be calculated from the volume obtained from the projected area and thickness of the object, and the specific surface area and bulk density of the material constituting the object. The specific surface area is measured, for example, by the nitrogen adsorption method.

[0078] The voids in the porous layer are connected from one main surface of the porous layer to the other main surface. That is, the voids in the porous layer are connected from the main surface of the porous layer in contact with the photoelectric conversion layer 4 to the main surface of the porous layer in contact with the electron transport layer 3. Thereby, the material of the photoelectric conversion layer 4 can fill the voids of the porous layer and reach the surface of the electron transport layer 3. Therefore, since the photoelectric conversion layer 4 and the electron transport layer 3 are in direct contact, the transfer of electrons is possible.

[0079] By providing the porous layer, an effect that the photoelectric conversion layer 4 can be easily formed is obtained. By providing the porous layer, the material of the photoelectric conversion layer 4 penetrates into the voids of the porous layer, and the porous layer serves as a scaffold for the photoelectric conversion layer 4. Therefore, it is less likely that the material of the photoelectric conversion layer 4 is repelled or aggregated on the surface of the porous layer. Thus, the photoelectric conversion layer 4 can be easily formed as a uniform film. The photoelectric conversion layer 4 can be formed by the above-described coating method, printing method, vapor deposition method, or the like.

[0080] It is considered that the porous layer increases the contact area between the perovskite layer and the electron transport layer, which is beneficial for electron transport and current collection.

[0081] [Other Embodiments] (Supplementary Note) From the description of the above embodiments, the following techniques are disclosed.

[0082] (Technique 1) A photoelectric conversion material containing a crystal phase including A, B, X, and I, where A is a monovalent cation and includes a monovalent inorganic cation, B is a divalent cation and includes Sn, X is at least one selected from the group consisting of F, Cl, and Br, The total molar ratio of X and I to B is 2.80 or more and 3.25 or less, The molar ratio of B to A is more than 1.00 and 1.50 or less, photoelectric conversion material.

[0083] With this configuration, the photoelectric conversion efficiency of the photoelectric conversion material can be improved.

[0084] (Technique 2) The photoelectric conversion material according to Technique 1, wherein the molar ratio of B to A is more than 1.00 and less than 1.30.

[0085] With this configuration, the photoelectric conversion efficiency of the photoelectric conversion material can be further improved.

[0086] (Technology 3) The photoelectric conversion material according to Technology 1 or 2, wherein the molar ratio of X to I is 0.03 or more and 0.19 or less.

[0087] With this configuration, the photoelectric conversion efficiency of the photoelectric conversion material can be further improved.

[0088] (Technology 4) In the X-ray diffraction pattern obtained by X-ray structure analysis using the Cu-Kα ray of the crystal phase, peaks exist in the range of diffraction angle 2θ of 25.14° or more and 25.17° or less, and 29.13° or more and 29.17° or less. The photoelectric conversion material according to any one of Technologies 1 to 3.

[0089] With this configuration, the photoelectric conversion efficiency of the photoelectric conversion material can be further improved.

[0090] (Technology 5) The crystal phase has a perovskite structure. The photoelectric conversion material according to any one of Technologies 1 to 4.

[0091] With this configuration, the photoelectric conversion efficiency of the photoelectric conversion material can be further improved.

[0092] (Technology 6) The A further contains a monovalent organic cation, and the ratio of the amount of substance of the monovalent inorganic cation to the total amount of substance of the monovalent inorganic cation and the monovalent organic cation is 5 mol% or more and 30 mol% or less. The photoelectric conversion material according to any one of Technologies 1 to 5.

[0093] With this configuration, the stability of the photoelectric conversion material can be improved.

[0094] (Technology 7) The A is the monovalent inorganic cation. The photoelectric conversion material according to any one of Technologies 1 to 5.

[0095] This configuration can improve the stability of the photoelectric conversion material.

[0096] (Technology 8) The photoelectric conversion material according to any one of claims 1 to 7, wherein the monovalent inorganic cation comprises Cs.

[0097] This configuration can further improve the photoelectric conversion efficiency of the photoelectric conversion material.

[0098] (Technology 9) 9. The photoelectric conversion material according to any one of claims 1 to 8, wherein X comprises at least one selected from the group consisting of F and Cl.

[0099] This configuration can further improve the photoelectric conversion efficiency of the photoelectric conversion material.

[0100] (Technology 10) A first electrode, a photoelectric conversion layer, and a second electrode are provided. The photoelectric conversion layer includes the photoelectric conversion material according to any one of techniques 1 to 9. Photoelectric conversion element.

[0101] This configuration makes it possible to provide a photoelectric conversion element with improved photoelectric conversion efficiency. EXAMPLES

[0102] Hereinafter, the present disclosure will be described in more detail with reference to examples.

[0103] Hereinafter, the preparation of raw material solutions for the photoelectric conversion layer and the hole transport layer and the film formation were carried out in a glove box in which the oxygen concentration and the moisture concentration were 1 ppm or less.

[0104] <Preparation of photoelectric conversion element (sequential lamination): Examples 1 to 3 and Comparative Example 1> First, a glass substrate was prepared. The substrate served as a support material for the photoelectric conversion element of the present disclosure.

[0105] An ITO (Indium Tin Oxide) layer and an ATO (Antimony Tin Oxide) layer were formed in this order on a substrate by sputtering. In this way, the first electrode was formed.

[0106] Next, a dense layer of titanium oxide (TiO 2 ) was formed on the ATO layer by sputtering. This dense layer of titanium oxide (TiO 2 ) corresponds to, for example, the electron transport layer described in the first embodiment above.

[0107] Next, 0.3 g of a titanium oxide paste of 30NR-D (manufactured by Gratcell Solar Materials Pty Ltd) was dissolved in 2 mL of a butanol solution. The resulting solution was applied onto the electron transport layer by spin coating and then fired at 500 °C for 30 minutes. In this way, a porous layer of titanium oxide was formed. Spin coating was performed at 4000 rpm for 20 seconds. Note that both the above-mentioned dense layer of titanium oxide (TiO 2 ) and the above-mentioned porous layer of titanium oxide have electron transport properties. Therefore, it is also possible to consider that the electron transport layer is constituted by the above-mentioned dense layer of titanium oxide (TiO 2 ) and the above-mentioned porous layer of titanium oxide.

[0108] A precursor solution of the photoelectric conversion layer was applied onto the porous layer by spin coating, then left standing at room temperature for 10 minutes and then fired at 120 °C for 30 minutes. In this way, the photoelectric conversion layer was formed. Spin coating was performed at 5000 rpm for 30 seconds while dropping chlorobenzene, which is a poor solvent.

[0109] The precursor solution of the photoelectric conversion layer was obtained as follows. First, SnI 2 and CsI were added to a mixed solution of DMF and DMSO (volume ratio of 1:1) to prepare a first solution of 0.8 M. Next, SnF 2By adding it to a mixed solution of DMF and DMSO (volume ratio of 1:1), a 0.8 M second solution was prepared. The second solution was added to the first solution. Thereby, a precursor solution was obtained.

[0110] In the examples, three types of precursor solutions were prepared. The precursor solutions with the addition concentrations of the second solution being 15 mol%, 20 mol%, and 25 mol% were designated as Example 1, Example 2, and Example 3, respectively. In Comparative Example 1, the second solution was not added, and only the first solution was used as the precursor solution for the photoelectric conversion layer.

[0111] Next, the raw material solution of the hole transport layer was coated on the photoelectric conversion layer by spin coating. In this way, the hole transport layer was formed. The raw material solution of the hole transport layer was prepared by dissolving 18 mg of PTAA (poly[bis(4-phenyl)(2,4,6-triphenyl)amine]) in 1 mL of chlorobenzene. The spin coating was performed at 4000 rpm for 20 seconds.

[0112] Next, a gold film was formed on the hole transport layer by evaporation. In this way, a second electrode with a thickness of 200 nm was formed.

[0113] Finally, a UV-curable epoxy resin was applied around the substrate, laminated with another glass substrate, and irradiated with UV light. In this way, the epoxy resin was cured to seal the power generation element.

[0114] <Fabrication of the photoelectric conversion element (inverted stack): Example 4, Example 5, and Comparative Example 2> First, a glass substrate was prepared. The substrate serves as a support material in the solar cell of the present disclosure.

[0115] An ITO layer was formed on the substrate by sputtering. In this way, the first electrode was formed.

[0116] Next, a PEDOT:PSS aqueous solution (manufactured by Heraeus) was spin-coated on the first electrode to form a hole transport layer. The spin coating was performed at 4000 rpm.

[0117] After applying the precursor solution of the photoelectric conversion layer onto the hole transport layer by spin coating, it was left standing at room temperature for 10 minutes and then baked at 120 °C for 30 minutes. In this way, the photoelectric conversion layer was formed. The spin coating was performed at 2500 rpm for 30 seconds.

[0118] The precursor solution of the photoelectric conversion layer was obtained as follows. First, SnI 2 and CsI were added to a mixed solution of DMF and DMSO (volume ratio 1:1) to prepare a 0.8 M first solution. Next, SnCl 2 was added to a mixed solution of DMF and DMSO (volume ratio 1:1) to prepare a 0.8 M second solution. The second solution was added to the first solution at 5 mol% and 10 mol%. In this way, the precursor solutions of the photoelectric conversion layers of Example 4 and Example 5 were obtained. In Comparative Example 2, the second solution was not added, and only the first solution was used as the precursor solution of the photoelectric conversion layer.

[0119] On the photoelectric conversion layer, a solution obtained by dissolving 20 mg of PCBM (phenyl C 61 methyl butyrate) in 1 mL of chlorobenzene was spin-coated at 4000 rpm for 20 seconds.

[0120] Subsequently, a film of BCP (bathocuproine) was formed by evaporation. In this way, an electron injection layer having a thickness of 6 nm was formed.

[0121] Next, a film of silver was formed by evaporation. In this way, a second electrode having a thickness of 200 nm was formed.

[0122] Finally, a UV curable epoxy resin was applied around the substrate, bonded to another glass substrate, and irradiated with UV light. In this way, the epoxy resin was cured and the power generation element was sealed.

[0123] <Fabrication of the photoelectric conversion element (sequential lamination): Examples 6 to 11, and Reference Example> Everything except for the precursor solution of the photoelectric conversion layer was fabricated in the same manner as in Examples 1 to 3 and Comparative Example 1.

[0124] The precursor solution of the photoelectric conversion layer was obtained as follows. First, SnI 2 , MAI, and CsI were added to a mixed solution of DMF and DMSO (volume ratio of 1:1) to prepare a 0.8 M first solution consisting of 7 levels with a molar ratio of CsI to MAI (CsI:MAI) of 100:0, 5:95, 10:90, 20:80, 30:70, 50:50, 0:100. Next, SnF 2 was added to a mixed solution of DMF and DMSO (volume ratio of 1:1) to prepare a 0.8 M second solution. The second solution was added to the first solution at 15 mol%. Thereby, a precursor solution was obtained.

[0125] <Characteristic Evaluation of Photoelectric Conversion Element> The IV characteristics of the photoelectric conversion elements of the examples and comparative examples were evaluated.

[0126] For the evaluation of the characteristics, a solar simulator (manufactured by Spectral Instruments Co., Ltd.) and an electrochemical analyzer ALS (manufactured by BAS Inc.) were used. The photoelectric conversion element was irradiated under simulated sunlight of 1 sun. The output of the solar simulator was set to 100 mW / cm 2 . By measuring the output current value while changing the applied voltage using the electrochemical analyzer, the current-voltage characteristics (i.e., IV characteristics) of the photoelectric conversion element were measured.

[0127] The measurement results are shown in Tables 1 and 2. η represents the conversion efficiency. J SC represents the short-circuit current density. V oc represents the open-circuit voltage. FF represents the fill factor. In addition, Table 1 also shows the total molar ratio of X and I to B ((X + I) / B) and the molar ratio of B to A (B / A) in the photoelectric conversion material. These molar ratios are shown as the charging ratios. Note that the above molar ratios in the photoelectric conversion material fabricated by the method of this example were substantially the same as the molar ratios obtained from the charging ratios.

[0128]

Table 1

[0129]

Table 2

[0130] Figure 3 is a graph showing the IV characteristics of the photoelectric conversion elements of Examples 1 to 3 and Comparative Example 1. Figure 4 is a graph showing the IV characteristics of the photoelectric conversion elements of Example 5 and Comparative Example 2. Figure 5 is a graph showing the IV characteristics of the photoelectric conversion elements of Examples 6 to 11 and the reference example. The horizontal axis in Figures 3 to 5 represents the applied voltage, and the vertical axis represents the current density. Note that in Figure 4, two IV curves of the photoelectric conversion element of Example 5 are shown. These are the IV curve swept from the high voltage side (forward sweep) and the IV curve swept from the low voltage side (reverse sweep). Note that the conversion efficiency is better when sweeping from the low voltage side. Table 1 shows the results when sweeping from the high voltage side for Example 5.

[0131] From the results shown in Table 1, Figures 3, and 4, it was found that the photoelectric conversion elements of Examples 1 to 3 had improved rectification of the device and an improved photoelectric conversion efficiency compared to the photoelectric conversion element of Comparative Example 1. Also, it was found that the photoelectric conversion element of Example 5 had rectification in the device and an improved photoelectric conversion efficiency compared to the photoelectric conversion element of Comparative Example 2.

[0132] In Figure 1, when a part of I in ASnI 3 (A is Cs, MA, or FA) is replaced with F, it has been shown that the Goldschmidt tolerance factor increases. Also, the Goldschmidt tolerance factor of CsSnI 2 when 15 mol% of SnF 3 is added is 0.8933, and that of MASnI 3 is 1.009. Therefore, while gradually replacing a part of I with F so as to fall within the range of the ideal value of 0.9 to 1.0, for Cs + with respect to MA+ It was considered to be better to adjust the mixing ratio of

[0133] The photoelectric conversion elements of Examples 6 to 11 are photoelectric conversion materials containing A, B, X, and I, and A is a monovalent inorganic cation (here, Cs + In contrast, in the photoelectric conversion element of the reference example, A in the photoelectric conversion material is a monovalent organic cation (here, MA + ) only. From the results shown in Table 2 and FIG. 5, the photoelectric conversion elements of Examples 6 to 11 had higher photoelectric conversion efficiency than the photoelectric conversion element of the Reference Example. + and M.A. + Cs for the sum of the amounts of substances + The photoelectric conversion elements of Examples 7 to 10, in which the proportion of the substance amount of Cs was in the range of 5 mol % to 30 mol %, had higher photoelectric conversion efficiency. + and M.A. + Molar ratio of (Cs + :MA + ) was 20:80, the photoelectric conversion efficiency was improved the most. Here, the photoelectric conversion element of Example 6 was produced by the same method as the photoelectric conversion element of Example 1, as described above. Therefore, in theory, the photoelectric conversion element of Example 6 exhibits the same performance as the photoelectric conversion element of Example 1. However, in reality, as shown in Tables 1 and 2, the photoelectric conversion efficiency of the photoelectric conversion element of Example 6 was lower than that of the photoelectric conversion element of Example 1. This is presumed to be due to the difference in oxygen concentration and hydrogen concentration in the manufacturing atmosphere in the manufacturing apparatus. In Example 6, the preparation for adjusting the oxygen concentration and hydrogen concentration in the manufacturing atmosphere was not as sufficient as in Example 1, and it is considered that the performance was lower than that of Example 1 due to the influence. Note that the manufacturing of the photoelectric conversion elements of Examples 7 to 11 and the reference example was performed in the same apparatus as Example 6 and under the same manufacturing atmosphere (i.e., under the same oxygen concentration and hydrogen concentration), so the comparison of the performance evaluation between the photoelectric conversion elements of Examples 6 to 11 and the reference example is correct.

[0134] For the photoelectric conversion layers of Example 1, Example 2, and Comparative Example 1, X-ray diffraction using Cu-Kα rays was measured. For the measurement of X-ray diffraction, a fully automatic multi-purpose X-ray diffractometer SmartLab (manufactured by Rigaku Corporation) was used. Using the software PDXL in the X-ray diffractometer, the crystal structure was identified by the RIR method. The results are shown in Table 3 and Table 4. Table 3 shows the peak positions in the X-ray diffraction pattern. The No. in Table 3 is the number assigned in order from the lower angle for the peaks detected by X-ray diffraction. The PDF card No. described in Table 4 represents the data number of the crystal structure of the identified space group. Table 4 further shows the lattice constants of the analyzed crystals. Also, FIG. 7 is a graph showing the X-ray diffraction pattern of CsSnI 3 which is the photoelectric conversion material of Comparative Example 1. FIG. 8 is a graph showing the X-ray diffraction pattern of the photoelectric conversion material of Example 1. FIG. 9 is a graph showing the X-ray diffraction pattern of the photoelectric conversion material of Example 2.

[0135]

Table 3

[0136]

Table 4

[0137] From the results shown in Table 3, Table 4, and FIGS. 7 to 9, a peak shift of 2θ was observed by adding 15 mol% of SnF 3 to CsSnI 2 . Also, the proportion of cubic crystals in the CsSnI 3 crystals calculated by the RIR method was 71% in Comparative Example 1, but increased to 87% in Example 1, increasing the symmetry of the crystals. Furthermore, the ionic radius of the X site calculated from the cubic crystal lattice constant by X-ray diffraction in Example 1 was 2.198 Å, slightly smaller than the ionic radius of 2.20 Å of I ― . Calculating the Goldschmidt tolerance factor gives 0.8933, and SnF 2It was found that the value slightly increased from 0.8932 before addition and approached the ideal value of 0.9. From these facts, the added SnF 2 by F - is thought to replace I - and constitute the crystal phase.

[0138] For the photoelectric conversion layers of Example 4, Example 5, and Comparative Example 2 as well, X-ray diffraction using Cu-Kα rays was measured in the same manner as in Example 1, Example 2, and Comparative Example 1. Using the software PDXL in the X-ray diffractometer, the crystal structure was identified by the RIR method. The results are shown in Table 5 and Table 6. Table 5 shows the peak positions in the X-ray diffraction pattern. The No. in Table 5 is the number assigned in order from the lower angle for the peaks detected by X-ray diffraction. The PDF card No. described in Table 6 represents the data number of the crystal structure of the identified space group. Table 6 further shows the lattice constants of the analyzed crystals. Fig. 10 is a graph showing the X-ray diffraction pattern of CsSnI 3 which is the photoelectric conversion material of Comparative Example 2. Fig. 11 is a graph showing the X-ray diffraction pattern of Example 4. Fig. 12 is a graph showing the X-ray diffraction pattern of the photoelectric conversion material of Example 5.

[0139]

Table 5

[0140]

Table 6

[0141] From the results shown in Table 5, Table 6, and Figs. 10 to 12, a peak shift of 2θ was observed by adding SnCl 3 to CsSnI 2 , and CsSnI 3The proportion of cubic crystals in the crystal was 60% in Comparative Example 2, but increased to 100% in Example 4, increasing the symmetry of the crystal. Furthermore, the ionic radius of the X site calculated from the cubic crystal lattice constant by X-ray diffraction in Example 4 was 2.196 Å, slightly smaller than the ionic radius of I ― of 2.20 Å. Calculating the Goldschmidt tolerance factor gave 0.8934, indicating that the value had slightly increased from 0.8932 before adding SnF 2 and was approaching the ideal value of 0.9. From these facts, it was considered that the added SnCl 2 caused Cl - to replace I - and form the crystal phase.

[0142] Figure 13A shows the crystal structure attributed to the cubic crystals contained in the photoelectric conversion material of the present disclosure. Figure 13B shows the crystal structure attributed to the orthorhombic crystals contained in the photoelectric conversion material of the present disclosure. Figure 13C shows the crystal structure attributed to the orthorhombic crystals contained in CsSnI 3

[0143] As can be seen from Table 4, adding 15 mol% of SnF 3 to CsSnI 2 decreased the identified lattice constant of the cubic crystal. Therefore, it was considered that F 2 in SnF - partially replaced I - . Also, adding 20 mol% of SnF 3 to CsSnI 2 decreased the symmetry of the crystal structure, and most became orthorhombic.

[0144] Comparing Example 1 with Example 2, the volume of the unit cell of the identified orthorhombic crystal (PDF card No. 01-080-8703) decreased from 917.76 Å 3 to 917.52 Å 3 . From this, in the orthorhombic crystal, since the interatomic distance within the unit cell became shorter, it was considered that F 2 in SnF - replaced I -It was considered that a part was replaced.

[0145] Figure 6 is a graph showing the PL emission lifetimes of the single films of the photoelectric conversion layers of Example 1 and Comparative Example 1.

[0146] The PL emission lifetime was measured using a near-infrared fluorescence lifetime measurement device (manufactured by Hamamatsu Photonics, C7990VIS / NIR). Among the constituent devices, H7422 was used for the photosensor module. The measurement results were analyzed with fluorescence lifetime software U8167-03.

[0147] The measurement sample for measuring the PL emission lifetime of the photoelectric conversion layer was fabricated in the same procedure as the photoelectric conversion layer of the photoelectric conversion element. Specifically, after applying the precursor solution of the photoelectric conversion layer onto a bare glass substrate by spin coating, it was baked at 120 °C for 30 minutes to form a single film. Spin coating was performed at 5000 rpm for 30 seconds while dropping chlorobenzene, which is a poor solvent. Next, a UV curable epoxy resin was applied around the substrate, and it was bonded to another glass substrate and irradiated with UV light. In this way, the epoxy resin was cured and the measurement sample was sealed. CsSnI 3 to SnF 2 By adding, the PL emission lifetime increased from 2.3 ns to 6.4 ns, and it was considered that the carrier diffusion length was improved. From this, it is considered that the defects in the crystal of the photoelectric conversion material were suppressed.

[0148] The measurement sample for performing measurement by inductively coupled plasma mass spectrometry (ICP-MS) and measurement by ion chromatography (IC) was fabricated in the same procedure as the photoelectric conversion layer of the photoelectric conversion element. Specifically, after applying the precursor solution of the photoelectric conversion layer onto a bare glass substrate by spin coating, it was baked at 120 °C for 30 minutes to form a single film. CsSnI 3 with SnF 2 Two films of Example 1 with 15 mol% of SnF added in the charged amount, and CsSnI 3 with SnCl 2Two membranes of Example 4 with 10 mol% added by the charged amount were prepared. One membrane each of Example 1 and Example 4 was placed in each glass beaker, pure water was added to dissolve the membrane on the substrate, and dilution was carried out to a fixed volume with pure water. Then, IC of this solution was performed, and quantification of I and F or Cl was carried out. The analytical apparatus used for IC was DX-500 manufactured by Dionex Corporation. Also, for some parts, after adding hydrochloric acid later, dilution was carried out to a fixed volume with pure water, ICP-MS was performed, and quantification of Cs was carried out. The ICP-MS used was Agilent-7700 manufactured by Agilent Technologies.

[0149] Furthermore, one membrane each of Example 1 and Example 4 was placed in each glass beaker, hydrochloric acid was added to dissolve the membrane on the glass substrate, and dilution was carried out to a fixed volume with pure water. For this lysate, quantification of Cs and Sn was carried out by ICP-MS. Since Sn undergoes hydrolysis to form Sn(OH) 2 in pure water dissolution, it was necessary to use a hydrochloric acid solution. Also, using the quantification value of Cs that is completely dissolved in both pure water and hydrochloric acid solution, a correction coefficient between the pure water lysate and the hydrochloric acid lysate was calculated. The calculated correction coefficient was multiplied by the Sn quantification result in the hydrochloric acid lysate to obtain the Sn quantification value present in the pure aqueous solution. Using the Sn quantification value and the Cs, I, F, Cl quantification results in the pure aqueous solution, the composition of the crystal film was calculated. The composition analysis results of this crystal film are shown in Table 7 with Cs = 1.0 in molar ratio. For Cs, SnF 2 and SnCl 2 were detected in amounts close to the charged amount.

[0150]

Table 7

Industrial Applicability

[0151] The photoelectric conversion element of the present disclosure can be used, for example, in a solar cell.

Claims

1. containing a crystal phase comprising A, B, X, and I, wherein, A is a monovalent cation and includes monovalent inorganic cations, B is a divalent cation and includes Sn, X is F, the total molar ratio of X and I to B is 2.80 or more and 3.25 or less, the molar ratio of B to A is more than 1.00 and 1.50 or less, in the X-ray diffraction pattern obtained by X-ray structural analysis using the Cu-Kα line of the crystal phase, peaks exist in the range of diffraction angle 2θ of 25.14° or more and 25.17° or less, and 29.13° or more and 29.17° or less, a photoelectric conversion material.

2. the molar ratio of B to A is more than 1.00 and less than 1.30, the photoelectric conversion material according to Claim 1.

3. the molar ratio of X to I is 0.03 or more and 0.19 or less, the photoelectric conversion material according to Claim 1.

4. the crystal phase has a perovskite structure, the photoelectric conversion material according to Claim 1.

5. A further includes a monovalent organic cation, the ratio of the amount of substance of the monovalent inorganic cation to the total amount of substance of the monovalent inorganic cation and the monovalent organic cation is 5 mol% or more and 30 mol% or less, the photoelectric conversion material according to Claim 1.

6. A is the monovalent inorganic cation, the photoelectric conversion material according to Claim 1.

7. the monovalent inorganic cation includes Cs, the photoelectric conversion material according to Claim 1.

8. comprising a first electrode, a photoelectric conversion layer, and a second electrode, the photoelectric conversion layer includes the photoelectric conversion material according to any one of Claims 1 to 7, a photoelectric conversion element.

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