Photoelectric conversion elements, photoelectric conversion devices, mobile bodies, building materials, and compositions
The introduction of a charge transport layer with cyclic conjugated compounds and calixarene compounds in photoelectric conversion elements enhances charge transport and extraction, addressing efficiency and durability issues in existing technologies.
Patent Information
- Application Number
- JP2025122562
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2024-09-25
- Filing Date
- 2025-07-22
- Publication Date
- 2026-04-06
AI Technical Summary
Existing photoelectric conversion elements, such as those described in Patent Documents 1 and 2, have room for improvement in achieving higher conversion efficiency, particularly in organic solar cells and perovskite solar cells, which face challenges in power generation efficiency and durability.
A photoelectric conversion element with a charge transport layer comprising a cyclic conjugated compound formed by conjugating multiple pyrrole rings and a calixarene compound, optionally with a surface modification layer, and a photoelectric conversion device incorporating this element, along with specific compounds to enhance current density and adhesion, are used to improve charge transport and extraction.
The configuration results in a photoelectric conversion element with enhanced efficiency by efficiently extracting and transferring charges, reducing accumulation, and improving adhesion and interfacial energy levels, thereby increasing overall photoelectric conversion efficiency.
Smart Images

Figure 2026058984000001_ABST
Abstract
Description
[Technical Field]
[0001] This disclosure relates to photoelectric conversion elements, photoelectric conversion devices, mobile devices, building materials, and compositions. [Background technology]
[0002] In order to address the depletion of fossil fuels and the environmental problems caused by their use, research is actively being conducted on renewable and clean alternative energy sources such as solar, wind, and hydroelectric power.
[0003] Among these, there is growing interest in solar cells, which directly convert sunlight into electrical energy. Here, a solar cell refers to a battery that absorbs light energy from sunlight and generates current-voltage using the photovoltaic effect, which generates electrons and holes.
[0004] Currently, np diode type silicon (Si) single-crystal based solar cells with light energy conversion efficiencies exceeding 20% are widely known and actually used in photovoltaic power generation. However, these have the problem of high cost per unit of power due to the need for high-temperature processing and the high price of the material itself. Furthermore, there are supply issues from the perspective of silicon resources.
[0005] On the other hand, solar cells using organic materials (hereinafter referred to as "organic solar cells") do not require high-temperature processing and can be produced using a so-called roll-to-roll method on sheet substrates, which is expected to reduce costs.
[0006] However, further improvements in power generation efficiency and durability are desired for the practical application of organic solar cells. In particular, perovskite solar cells, which have a perovskite structure crystal as the photoelectric conversion layer, are being developed toward the practical application of solar cells because of their excellent photoelectric conversion properties.
[0007] For example, Patent Document 1 describes a configuration in which an organic semiconductor component and an electron-withdrawing group are bonded to a heteroatom are included in the hole transport layer. Furthermore, Patent Document 2 describes a configuration having a charge transport layer containing a phthalocyanine compound and an aromatic ring compound having a hydroxyl group. [Prior art documents] [Patent Documents]
[0008] [Patent Document 1] Japanese Patent Publication No. 2018-82140 [Patent Document 2] Japanese Patent Publication No. 2024-60579 [Overview of the project] [Problems that the invention aims to solve]
[0009] According to the inventors' research, the photoelectric conversion elements described in Patent Documents 1 and 2 still had room for improvement in order to achieve even higher conversion efficiency. Therefore, an objective of this disclosure is to provide a photoelectric conversion element with superior photoelectric conversion efficiency. Another objective of this disclosure is to provide a coating composition capable of improving photoelectric conversion efficiency. [Means for solving the problem]
[0010] The above objectives are achieved by the following disclosure. That is, this disclosure is: A first electrode, a second electrode, and a photoelectric conversion layer containing a perovskite crystal disposed between the first electrode and the second electrode. A photoelectric conversion element having, A charge transport layer is provided between the photoelectric conversion layer and the first electrode. The charge transport layer comprises a cyclic conjugated compound in which multiple pyrrole rings are conjugated together, and a calixarene compound. The photoelectric conversion element is characterized in that the charge transport layer contains a compound that improves current density, or the photoelectric conversion element has a surface modification layer between the charge transport layer and the first electrode. Furthermore, this disclosure relates to a photoelectric conversion device having the above-mentioned photoelectric conversion element. Furthermore, this disclosure is, Pigments are cyclic conjugated compounds in which multiple pyrrole rings are conjugated together, Calixarene compounds and Solvents and, Compounds that improve current density, or compounds that form a surface modification layer. It is a composition containing [the specified ingredient]. [Effects of the Invention]
[0011] According to this disclosure, it is possible to provide a photoelectric conversion element with excellent photoelectric conversion efficiency, a photoelectric conversion device, and a coating composition that can improve photoelectric conversion efficiency. [Brief explanation of the drawing]
[0012] [Figure 1] This is a schematic cross-sectional view in the thickness direction of one embodiment of the photoelectric conversion element of the present disclosure. [Figure 2] This is a schematic perspective view showing one embodiment of a mobile body equipped with a photoelectric conversion element of the present disclosure. [Figure 3] This is a schematic perspective view showing one embodiment of a building material equipped with a photoelectric conversion element of the present disclosure. [Modes for carrying out the invention]
[0013] <Embodiment> The embodiments relate to a photoelectric conversion element and a composition. The photoelectric conversion element disclosed herein is A first electrode, a second electrode, and a photoelectric conversion layer containing a perovskite crystal disposed between the first electrode and the second electrode. A photoelectric conversion element having, A charge transport layer is provided between the photoelectric conversion layer and the first electrode. The charge transport layer comprises a cyclic conjugated compound in which multiple pyrrole rings are conjugated together, and a calixarene compound. The charge transport layer contains a compound that improves current density, or the photoelectric conversion element is characterized by having a surface modification layer between the charge transport layer and the first electrode. Furthermore, the compositions of this disclosure are Pigments are cyclic conjugated compounds in which multiple pyrrole rings are conjugated together, Calixarene compounds and Solvents and, Compounds that improve current density, or compounds that form a surface modification layer. It contains.
[0014] As a result of their investigation, the inventors have found that having the above-mentioned charge transport layer results in a photoelectric conversion element with excellent photoelectric conversion efficiency. Although the details of why such high efficiency is obtained in this disclosure are not clear, it is thought to be as follows.
[0015] The photoelectric conversion element of the present disclosure comprises a charge transport layer comprising a cyclic conjugated compound formed by the conjugation bonding of a plurality of pyrrole rings and a calixarene compound, wherein the charge transport layer comprises a compound that improves the current density, or the photoelectric conversion element has a surface modification layer between the charge transport layer and the first electrode.
[0016] Specifically, for example, if the charge transport layer contains a cyclic conjugated compound formed by the conjugation of multiple pyrrole rings having charge transport ability, a calixarene compound, and a compound that improves current density, then it is possible to efficiently extract charge from the photoelectric conversion layer and efficiently transfer the charge to a layer located on the opposite side of the photoelectric conversion layer without it accumulating in the charge transport layer. By including a compound that improves current density in the charge transport layer, the charge transport ability of the cyclic conjugated compound formed by the conjugation of multiple pyrrole rings is enhanced, and the flow of charge can be increased.
[0017] Furthermore, the calixarene compound can facilitate the transfer of increased charge between cyclic conjugated compounds, which are formed by the conjugation of multiple pyrrole rings. In addition, while the interfacial energy levels and adhesion are important for efficiently transferring charge to the layer opposite the photoelectric conversion layer, the configuration of this disclosure allows for the selection of energy levels and improvement of adhesion without reducing the charge transport capacity in the charge transport layer.
[0018] This disclosure prefers that the cyclic conjugated compound be a pigment. The charge transport ability can be further improved if the cyclic conjugated compound is a pigment. Furthermore, the average particle size of the pigment is preferably 10 nm to 400 nm, and more preferably 50 nm to 250 nm. Within this particle size range, the charge transport ability can be further improved.
[0019] This disclosure indicates that, from the viewpoint of charge transport ability, the cyclic conjugated compound is more preferably a phthalocyanine compound, and even more preferably a compound having the structure shown in the following formula (Pc-1). [ka]
[0020] In this disclosure, in formula (Pc-1), M is preferably H2, a ligand-containing metal atom, or a ligand-less metal atom, and more preferably ligand-containing gallium, aluminum, titanium, iron, or silicon. In this disclosure, the cyclic conjugated compound is preferably a hydroxygallium compound or a chlorogallium phthalocyanine compound.
[0021] In particular, when M in the above equation (Pc-1) is H2, the above equation (Pc-1) is expressed as the following equation (Pc-2). [ka] To change the energy levels of the charge transport layer and improve charge extraction, substituents may be introduced into the cyclic conjugated compound.
[0022] It is preferable that the calixarene compound be represented by the following formula (A) in terms of charge extraction and transfer between and at the interface of cyclic conjugated compounds formed by conjugation of a plurality of pyrrole rings.
Chemical formula
[0024] ~R 5 are each independently within each repeating unit and each independently for every n repeating units, R 1 represents a hydrogen atom or an alkyl group, R 2 represents a substituted or unsubstituted alkylene group, R 3 ~R 5 represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted -Y-Ar group, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted heterocyclic group, R 3 ~R 5 Among them, at least one is a -Y-Ar group having a substituent. The -Y- represents -CH=N-, -CH=CH-, or -N=N-, and the Ar represents a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted heterocyclic group. n is an integer of 3 or more and 20 or less.)
[0023] Examples of the alkyl group represented by the above R 1 and R 3 ~R 5 include a methyl group, an ethyl group, a propyl group, and a butyl group. R 3 ~R 5 Examples of the aromatic hydrocarbon represented by include benzene, naphthalene, fluorene, phenanthrene, anthracene, fluoranthene, and pyrene.
[0024] Also, the above R 3 ~R 5Examples of heterocycles mentioned include furan, thiophene, pyridine, indole, benzothiazole, carbazole, benzocarbazole, acridone, dibenzothiophene, benzoxazole, benzotriazole, oxathiazole, thiazole, phenazine, cinnoline, and benzosinnoline.
[0025] Also, R 3 ~R 5 Examples of substituents that alkyl groups, phenylazo groups, aromatic hydrocarbon groups, and heterocycles may have include alkyl groups such as methyl, ethyl, propyl, and butyl groups; alkoxy groups such as methoxy and ethoxy groups; dialkylamino groups such as dimethylamino and diethylamino groups; alkoxycarbonyl groups such as methoxycarbonyl and ethoxycarbonyl groups; halogen atoms such as fluorine, chlorine, and bromine atoms; hydroxyl groups, nitro groups, cyano groups, and halomethyl groups.
[0026] This disclosure prefers that n in formula (A) be 4 or 8 from the viewpoint of charge extraction and transfer. Furthermore, this disclosure relates to the R of formula (A) above. 4 However, it is preferable from the viewpoint of charge extraction and transfer that each of the n repeating units independently has a nitrophenylazo group or a dinitrophenylazo group. Furthermore, this disclosure prefers that the calixarene compound of formula (A) has a molecular weight of 10,000 or less, from the viewpoint of charge extraction and transfer.
[0027] Furthermore, in this disclosure, R 1 However, it is preferable that each of the n repeating units is independently hydrogen, a methyl group, an ethyl group, or a propyl group. Also, R 2 However, it is preferable that each of the n repeating units is independently a methylene group, an ethylene group, or a propylene group. 3 , R 5 However, it is preferable that it be a hydrogen group.
[0028] This disclosure prefers that the calixarene compound of formula (A) be a mixture of the compound shown in formula (C-1), the compound shown in formula (C-2), the compound shown in formula (C-3), and the compound shown in formula (C-4) below, from the viewpoint of charge extraction and transfer. [ka] [ka] [ka] [ka]
[0029] This disclosure prefers that the compound that improves the current density is a dopant material or an ionic liquid material. Examples of dopant materials include those described in Non-Patent Literature (J. Lee, et al., EcoMat vol. 5, p. e12414 (2023)). The combination of cation and anion is not limited.
[0030] Examples of cations in ionic liquid materials include imidazolium salts, pyrrolidinium salts, pyridinium salts, piperidinium salts, ammonium salts, phosphonium salts, sulfonium salts, and phthalocyanine salts. Examples of anions include the following: [ka]
[0031] Furthermore, the compound that improves the current density may be a compound in which the anion is substituted with the cation, as shown in the following formula (Pc-TFSI). [ka]
[0032] This disclosure is preferable in that the ratio of the mass of the compound that improves the current density to the mass of the calixarene compound is 0.002 or more and 10 or less, in which the accumulation of charge resulting from the extraction and transfer of the increased charge due to the improved charge transport capacity can be suppressed.
[0033] This disclosure is preferable in that, if the ratio of the mass of the calixarene compound to the mass of the cyclic conjugated compound formed by the conjugation of the plurality of pyrrole rings is 0.01 or more and 0.5 or less, it is possible to suppress the accumulation of charge that occurs during the extraction and transfer of charge between the cyclic conjugated compound formed by the conjugation of the plurality of pyrrole rings.
[0034] This disclosure is preferable in that the charge transport capacity in the charge transport layer can be further improved if the ratio of the mass of the compound that improves the current density to the mass of the cyclic conjugated compound formed by the conjugation bonding of the plurality of pyrrole rings is 0.0001 or more and 1 or less.
[0035] In the photoelectric conversion element disclosed herein, it is preferable that the charge transport layer contains a resin. Adding a resin is preferable because it suppresses the formation of voids in the charge transport layer, enhances adhesion between materials, improves charge transport ability, and suppresses stagnation that occurs during charge extraction and transfer. Furthermore, the SP value and functional groups of the resin can be appropriately selected to suppress the formation of voids.
[0036] Examples of functional groups include hydroxyl groups, carbonyl groups, ester groups, ether groups, carboxyl groups, methoxy groups, amino groups, sulfo groups, aldehyde groups, amide groups, halogens, sulfide groups, cyano groups, thienyl groups, pyridine, furan, pyrazole, imidazole, oxazole, and thiazole.
[0037] In the photoelectric conversion element of this disclosure, it is preferable that the resin is an insulating resin. If it is an insulating resin, the charge rectification required for the photoelectric conversion element can be maintained. The volume resistivity of the charge transport insulating resin is 1.0 × 10⁻⁶. 9 A value of Ω·cm or greater is preferable, and moreover, 1.0 × 10⁻⁶ 10 Ω cm or more, 1.0×1015 A value of Ω·cm or less is preferable.
[0038] This disclosure is preferable in that the ratio of the mass of the calixarene compound to the mass of the resin is 0.2 or more and 10 or less, as this can suppress the accumulation of charge that occurs during charge extraction and transfer.
[0039] Furthermore, this disclosure is preferable in that the charge transport capacity in the charge transport layer can be further improved if the ratio of the mass of the compound that improves the current density to the mass of the resin is 0.002 or more and 10 or less.
[0040] Furthermore, this disclosure is preferable in that the charge transport capacity in the charge transport layer can be further improved if the ratio of the mass of the cyclic conjugated compound, which is formed by the conjugation of multiple pyrrole rings, to the mass of the resin is 5 or more and 30 or less.
[0041] The thickness of the charge transport layer is preferably 5 nm to 800 nm. A thickness of 5 nm or more can be expected to suppress interlayer migration, and a thickness of 800 nm or less facilitates efficient charge transport to each electrode. More preferably, the thickness is 40 nm to 600 nm, and even more preferably 40 nm to 400 nm. By changing the thickness, surface smoothness can be controlled, and an improvement in the charge transport capacity at the interface can be expected.
[0042] The photoelectric conversion element of the present disclosure has, for example, a charge transport layer between the photoelectric conversion layer and the first electrode, comprising a cyclic conjugated compound in which a plurality of pyrrole rings are conjugated together and a calixarene compound, and a surface modification layer between the charge transport layer and the first electrode.
[0043] As a result of their investigation, the inventors have found that having the above configuration results in a photoelectric conversion element with excellent photoelectric conversion efficiency. Although the details of why such high efficiency is obtained in this disclosure are not clear, it is thought to be as follows.
[0044] The charge transport layer comprises a cyclic conjugated compound and a calixarene compound, each consisting of multiple pyrrole rings with charge transport capabilities bonded together. By having a surface modification layer between the charge transport layer and the first electrode, charge retention in the charge transport layer is reduced, and charge can be efficiently transferred to the layer located opposite the photoelectric conversion layer. Furthermore, by appropriately configuring the wettability and interface states with the surface modification layer, charge can be transferred even more efficiently, improving the photoelectric conversion efficiency.
[0045] In the photoelectric conversion element of the present disclosure, the surface modification layer preferably comprises a dopant material, an ionic liquid material, or a passivation material, and more preferably, in order to further enhance the charge transfer capability at the interface, the surface modification layer is an ionic insulating material. Examples of passivation materials include the following: [ka] [ka] [ka]
[0046] The thickness of the surface modification layer is preferably 100 nm or less. A thickness of 100 nm or less facilitates good charge transport. More preferably, the thickness is 0.1 nm or more and 20 nm or less.
[0047] The composition of this disclosure contains a pigment which is a cyclic conjugated compound in which multiple pyrrole rings are conjugated together, a calixarene compound, a solvent, and a compound that improves current density or forms a surface modified layer. Each substance is as described above. The solvent can be any solvent that disperses and dissolves each substance, for example, 2-propanol or butanol.
[0048] When this composition is used to form a film for a photoelectric conversion element, the photoelectric conversion efficiency can be improved. The surface modification layer can also be formed by migrating the compounds in the above composition to the surface during coating. For surface migration, it is preferable that the compound forming the surface modification layer has an element or structure with low surface free energy, such as fluorine or siloxane.
[0049] As described above, the effects of this disclosure can be achieved through the synergistic interactions of each component.
[0050] The present disclosure will be described in detail below with reference to preferred embodiments. The present disclosure is not limited to the embodiments described below, and the scope of the present disclosure also includes modifications, improvements, etc., to the extent appropriate to the embodiments described below, based on the ordinary knowledge of those skilled in the art, without departing from the spirit of the present disclosure.
[0051] In this specification, the term "layer" refers not only to layers with clear boundaries or flat, thin films, but also to layers with gradually changing concentrations of constituent elements, and layers that can combine with other layers to form complex, interwoven structures.
[0052] Furthermore, layer analysis can be performed, for example, by measuring using MS / NMR / XPS / IR / XRD / TEM / SEM / EDS / SPM to confirm the compounds contained in the layers and their composition.
[0053] Figure 1 is a schematic cross-sectional view showing the configuration of one embodiment of the photoelectric conversion element of the present disclosure. The photoelectric conversion element of the present disclosure has a first electrode 7, a second electrode 3, and a photoelectric conversion layer 5 containing a perovskite crystal disposed between the first electrode 7 and the second electrode 3, and a charge transport layer 6 between the photoelectric conversion layer 5 and the first electrode 7.
[0054] The substrate 2 has a second electrode 3, an electron transport layer 4, a photoelectric conversion layer 5, a charge transport layer 6, and a first electrode 7. One of the first electrode 7 and the second electrode 3 is a positive electrode and the other is a negative electrode, and current can be extracted by connecting the first electrode 7 and the second electrode 3 to an external circuit.
[0055] The photoelectric conversion layer 5 is excited by light incident through the substrate 2, the second electrode 3, and the electron transport layer 4, or the first electrode 7 and the charge transport layer 6, generating electrons or holes. That is, the photoelectric conversion layer 5 generates an electric current between the first electrode 7 and the second electrode 3.
[0056] The electron transport layer 4 is a layer placed between the photoelectric conversion layer 5 and the two electrodes (second electrode 3 and first electrode 7), and may not be formed in some cases. Multiple electron transport layers 4 and photoelectric conversion layers 5 may be stacked on top of each other.
[0057] This configuration can also be called a tandem structure. Alternatively, the photoelectric conversion element may be fabricated on the substrate 2 in the following order: first electrode 7, charge transport layer 6, photoelectric conversion layer 5, electron transport layer 4, and second electrode 3.
[0058] The following describes each component constituting the photoelectric conversion element of this disclosure. [Photoelectric conversion element] The photoelectric conversion element of this disclosure is characterized by having a photoelectric conversion layer containing a perovskite crystal, a charge transport layer, or a photoelectric conversion layer containing a perovskite crystal, a charge transport layer, and a surface modification layer.
[0059] The photoelectric conversion element can be configured in either a forward layer configuration, where a layer with P-type semiconductor characteristics is formed after the photoelectric conversion layer, or an inverse layer configuration, where a layer with N-type semiconductor characteristics is formed after the photoelectric conversion layer. Furthermore, to improve the photoelectric conversion efficiency, a tandem type configuration in which photoelectric conversion elements are stacked may be used.
[0060] The photoelectric conversion elements to be stacked are not limited to the type of photoelectric conversion element, but also include perovskite solar cells that use perovskite crystals as the photoelectric conversion layer, as well as silicon solar cells and CIGS solar cells.
[0061] Methods for forming each layer of the photoelectric conversion element disclosed herein include coating methods and vapor deposition methods. Examples of coating methods include immersion coating, spin coating, spray coating, inkjet coating, meniscus coating, screen coating, roll coating, die coating, blade coating, curtain coating, and wire bar coating.
[0062] The coating method involves preparing the coating solution for each layer, applying them in the desired order, and then drying them. These film formation methods can be selected according to the specific requirements of each layer. The following explains each layer.
[0063] 〔substrate〕 The photoelectric conversion element 1 of this disclosure may include a substrate 2, for example, a transparent glass substrate made of soda-lime glass or alkali-free glass, a ceramic substrate, or a transparent plastic substrate. When light is taken in from the first electrode 7 side, the substrate 2 can be made of an opaque material, and when light is taken in from the second electrode 3 side, the substrate 2 is made of a transparent material.
[0064] 〔electrode〕 The materials for the first electrode 7 and the second electrode 3 are not particularly limited, and conventionally known materials can be used. Examples include metals such as gold, silver, titanium, and copper; sodium, sodium-potassium alloys; lithium, magnesium, carbon, carbon nanotubes; aluminum, magnesium-silver mixtures; magnesium-indium mixtures; aluminum-lithium alloys; Al / Al2O3 mixtures; and Al / LiF mixtures.
[0065] Examples of transparent electrode materials include conductive transparent materials and conductive transparent polymers such as CuI, ITO (indium tin oxide), SnO2, AZO (aluminum zinc oxide), IZO (indium zinc oxide), GZO (gallium zinc oxide), FTO (fluorine-doped tin oxide), and ATO (antimond-doped tin oxide). These materials may be used individually or in combination of two or more.
[0066] The first electrode 7 and the second electrode 3 are such that at least one of the electrodes on the light incident side is a transparent electrode, and the other may be a transparent electrode or may also serve as a reflective layer formed of a light-reflective material, or may be a transparent electrode provided with a reflective layer on the side opposite to the light incident side. When the first electrode 7 is on the light incident side, the second electrode 3 may be used as the transparent electrode and the substrate 2 may be used as the reflective layer. Note that the transparent electrode may be a patterned electrode.
[0067] 〔Photoelectric conversion layer〕 The photoelectric conversion layer 5 has a crystal with a perovskite structure. The crystal with a perovskite structure used in the present disclosure is preferably represented by the following general formula [1]. A o B p X q [1]
[0068] In the above general formula [1], A is a cation, B is a cation, and X is an anion. o, p, q each satisfy 0 < o ≤ 10, 0 < p ≤ 10, 0 < q ≤ 20, and A, B, X may each be composed of a single material or may be used in combination of two or more types. An additive may be added within the range where the above general formula holds.
[0069] Generally, the above general formula forms a perovskite crystal with a three-dimensional structure. However, when the cation of A constituting it is too large to fit within the crystal of the three-dimensional perovskite structure, a crystal with a two-dimensional perovskite structure, a crystal with a 2.5-dimensional perovskite structure having both two-dimensional and three-dimensional properties, a two-layer crystal of a three-dimensional and two-dimensional perovskite structure, or a crystal with a mixed three-dimensional·two-dimensional perovskite structure is formed, and all of them function as the photoelectric conversion layer.
[0070] The two-layer crystal of a three-dimensional and two-dimensional perovskite refers to a crystal in which crystals with a three-dimensional and two-dimensional perovskite structure are stacked as independent and separate layers, and the mixed three-dimensional·two-dimensional perovskite indicates a crystal having a structure in which both regions or domains of a two-dimensional or 2.5-dimensional layered and three-dimensional perovskite structure are mixed.
[0071] Crystals of two-dimensional perovskites or 2.5-dimensional perovskite structures may form RP (Ruddlesden-Popper), DJ (Dion-Jacobson), or ACI (Alternating cations in the interlayer) type perovskite structures.
[0072] The type of cation A in the above general formula [1] is not particularly limited. A may or may not have substituents, and the following structural formulas are examples. [ka] [ka]
[0073] Furthermore, while the inorganic atoms are not particularly limited, lithium, cesium, sodium, potassium, and rubidium are preferred. These organic molecules or inorganic atoms may be used individually, or two or more may be used in combination.
[0074] In the general formula [1] above, B is a cation atom, and examples include lead, tin, bismuth, zinc, titanium, antimony, nickel, iron, cobalt, silver, copper, gallium, germanium, magnesium, calcium, indium, aluminum, manganese, chromium, molybdenum, and europium. Among these, lead, tin, bismuth, and silver are preferred from the viewpoint of the stability of the perovskite crystal structure. These atoms may be used individually or in combination of two or more.
[0075] In the above general formula [1], X is a halogen or chalcogen atom, such as chlorine, bromine, iodine, oxygen, sulfur, selenium, tellurium, or polonium. These halogen or chalcogen atoms may be used individually or in combination of two or more.
[0076] In particular, halogen atoms are preferred because the inclusion of halogens in the structure makes the perovskite crystals more soluble in organic solvents, enabling their application to inexpensive printing methods and the like. Furthermore, iodine is more preferred because it narrows the energy band gap of the perovskite crystals.
[0077] Specifically, 3D perovskites, 2D perovskites, and mixed 3D-2D perovskites are MAPbI3, FAPbCl3, FAPbI3, and MAPbI x Br 3-x MAPbI x Cl 3-x , Cs 0.05 (MA 0.17 FA 0.83 ) 0.95 Pb(I 0.83 Br 0.17 )3, {Cs x1 (Fa x2 MA 1-x2 ) 1-x1} x3 Pb(I x4 Br 1-x4 ) x5 , Cs 0.05 FA 0.88 MA 0.07 PbI 2.56 Br 0.44 (FAPbI3) 0.95 (MAPbBr3) 0.05 (FAPbI3) 0.85 (MAPbBr3) 0.15 , CsPbI3, CsPbBr3, Cs x (MA) 1-x PbI3,Cs x (FA) 1-x PbI3,MA x (FA) 1-x PbI3, MA 0.17 FA 0.83 Pb(I 0.83 Br 0.17 )3, Cs 0.15 FA 0.85 PbI 2.55 Br 0.45 ,Cs 0.05 FA 0.88 MA 0.07 PbI2.56 Br 0.44 、Cs 0.15 FA 0.85 PbI 2.55 Br 0.45 、(PEA)2(MA)2Pb3I 10 ,(PTA)2(MA)4Pb5I 16 ,(PEA)2(MA)4Pb5I 16 ,(ThMA)2(MA)2Pb3I 10 、(3BBA)2(MA)2Pb3I 10 ,(ThMA)2(FA)4Pb5I 16 、(pF-PEA)2(FA 0.3 MA 0.7 )4Pb5I 16 、(PDMA)FA2Pb3I 10 、(3AMPY)(MA)3Pb4I 13 ,(PDMA)MA5Pb6I 19 、(PDMA)MA3Pb4I 13 、(BA 0.9 PEA 0.1 )2MA4Pb5I 16 、(BA 0.9 PEA 0.1 )2MA3Pb4I 13 、(BA)2、MA2Pb3I 10 、(BA)2MA3Pb4I 13 、(BA)2MA4Pb5I 16 、(BA)2MA3Pb4I 13 、CsSnBr3、CsSnI3、FA 0.75 MA 0.25 Sn 0.95 Ge 0.05 I3, FAMASnGeI3, FASnBr3, FASnI3, MA2Sn3I8, MASnBr3, MASnGeI3, MASnI3 are preferred.
[0078] Depending on the purpose, the A site, B site, or X site in the above general formula [1] may be adjusted to be too little or too much, and the combinations of x1 to x5 may be changed depending on the purpose. Examples of combinations of x1 to x5 are shown in Table 1. Particularly preferred ranges are 0.03≦x1≦0.10, 0.80≦x2≦0.96, 0.95≦x3≦1.05, 0.80≦x4≦0.96, and 2.95≦x5≦3.05. MACl may also be included as the material for forming the perovskite crystal.
[0079] [Table 1]
[0080] The perovskite crystal described above preferably has a cubic crystal structure in which a metal atom B is located at the body center, organic molecules A are located at each vertex, and halogen atoms X are located at the face centers. Although the details are not clear, it is presumed that having such a structure allows the orientation of octahedra within the crystal lattice to be easily changed, thereby increasing the electron mobility in the perovskite crystal and improving the photoelectric conversion efficiency of the photoelectric conversion element.
[0081] The perovskite crystal used in this disclosure is preferably a crystalline semiconductor. A crystalline semiconductor is a semiconductor in which the X-ray scattering intensity distribution can be measured and a scattering peak can be detected. Because the perovskite crystal is a crystalline semiconductor, the electron mobility in the perovskite crystal is increased, improving the photoelectric conversion efficiency of the photoelectric conversion element.
[0082] The thickness of the photoelectric conversion layer according to this disclosure is preferably 5 nm or more and 2000 nm or less. If the thickness is 5 nm or more, light can be absorbed sufficiently, and if it is 2000 nm or less, the generated charge can be transported to each electrode. A more preferable lower limit is 50 nm or more, a more preferable upper limit is 1200 nm, an even more preferable lower limit is 100 nm, and an even more preferable upper limit is 1000 nm.
[0083] [Hole transport layer] In this disclosure, a hole transport layer may be provided between the charge transport layer and the first electrode 7. The material of the hole transport layer is not particularly limited, and examples include spirofluorene compounds, triphenylamine compounds, chrysene compounds, pyrene compounds, phthalocyanine compounds, carbazole compounds, fluorene compounds, phenylcyclohexane compounds, benzidine compounds, phenoxazine compounds, phenylenediamine compounds, thiocyanate compounds, and thiophene compounds. In particular, it is preferable that the material has an aromatic ring from the viewpoint of compatibility at the membrane interface, and Spiro-OMeTAD, PTAA, and phthalocyanine compounds are preferred.
[0084] Furthermore, the hole transport layer may contain dopants as additives to improve its charge transport capability. Examples of substances that can be used as dopants include lithium compounds such as bis(trifluoromethanesulfonyl)imide lithium, cobalt compounds such as [tris(2-(1H-pyrazole-1-yl)-4-tert-butylpyridine)cobalt(3)tris(bis(trifluoromethylsulfonyl)imide)], boron compounds such as tetrakis(pentafluorophenyl)borate, molybdenum compounds such as tris[1-(methoxycarbonyl)-2-(trifluoromethyl)-ethane-1,2-dithiolene]molybdenum, organic compounds having a tetracyanoquinodimethane skeleton such as 2,3,4,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane, and organic compounds having a pyridine skeleton such as 4-tert-butylpyridine.
[0085] The thickness of the hole transport layer is preferably 1 nm to 1000 nm, more preferably 5 nm to 500 nm, and particularly preferably 10 nm to 200 nm.
[0086] [Electron transport layer] In the photoelectric conversion element of this disclosure, an electron transport layer 4 may be placed between the second electrode 3 and the photoelectric conversion layer 5, as shown in Figure 1.
[0087] The material of the electron transport layer 4 is not particularly limited and includes, for example, N-type conductive polymers, N-type low molecular weight organic semiconductors, N-type metal oxides, N-type metal sulfides, alkali metal halides, alkali metals, surfactants, and more specifically, cyano group-containing polyphenylene vinylene, boron-containing polymers, vasocuproin, vasophenanthrene, hydroxyquinolinatoaluminum, oxadiazole compounds, benzimidazole compounds, naphthalenetetracarboxylic acid compounds, fullerene compounds, perylene compounds, phosphine oxide compounds, phosphine sulfide compounds, fluoro group-containing phthalocyanines, titanium dioxide, zinc oxide, indium oxide, tin oxide, gallium oxide, tin sulfide, indium sulfide, and zinc sulfide.
[0088] The preferred lower limit for the thickness of the electron transport layer 4 is 1 nm, and the preferred upper limit is 2000 nm. If the thickness of the electron transport layer 4 is 1 nm or more, holes can be sufficiently blocked, and if it is 2000 nm or less, it will not be a resistance during electron transport, and the photoelectric conversion efficiency will be high. A more preferred lower limit for the thickness is 3 nm, a more preferred upper limit is 1000 nm, an even more preferred lower limit is 5 nm, and an even more preferred upper limit is 500 nm.
[0089] [Middle class] The photoelectric conversion element 1 may have one or more intermediate layers between each layer for the purpose of reducing energy gaps that hinder charge transfer or suppressing migration between layers. The intermediate layers may contain either an inorganic compound or an organic compound.
[0090] Examples of inorganic compounds include Al compounds, Mo compounds, Ni compounds, Ti compounds, Sn compounds, and Zn compounds. Examples of organic compounds include fullerene compounds, phthalocyanine compounds, spirofluorene compounds, triphenylamine compounds, chrysene compounds, pyrene compounds, phthalocyanine compounds, carbazole compounds, fluorene compounds, phenylcyclohexane compounds, benzidine compounds, phenoxazine compounds, phenylenediamine compounds, thiocyanate compounds, butyral resins, acrylic resins, polycarbonate resins, polyester resins, polyvinyl acetal resins, epoxy resins, melamine resins, polyurethane resins, phenolic resins, polyvinylphenol resins, alkyd resins, polyvinyl alcohol resins, polyethylene oxide resins, polypropylene oxide resins, polyamide resins, polyamic acid resins, polyimide resins, polyamideimide resins, and cellulose resins. These compounds may be used individually or in combination of two or more. These compounds can also be produced by mixing them into a layer or by surface contact / adhesion via rinsing.
[0091] The thickness of the intermediate layer is preferably 5 nm to 800 nm. If the thickness is 5 nm or more, an effect of suppressing interlayer migration can be expected, and if the thickness is 800 nm or less, charge can be easily transported to each electrode. More preferably, it is 40 nm to 600 nm, and even more preferably 40 nm to 400 nm.
[0092] <Application Examples> [Photoelectric converter] The photoelectric conversion device disclosed herein has a photoelectric conversion element disclosed herein. A photoelectric conversion device can be configured by using multiple photoelectric conversion elements disclosed herein. When multiple photoelectric conversion elements are connected together, such a photoelectric conversion device may also be called a photoelectric conversion cell or a photoelectric conversion module. The photoelectric conversion element may be made up of elements with different absorption wavelengths stacked together to increase the output voltage. The photoelectric conversion device also has the photoelectric conversion element disclosed herein and an inverter. The inverter may be a converter that converts DC to AC. The photoelectric conversion device may have a power storage unit connected to the photoelectric conversion element. The power storage unit is not limited as long as it can store electricity. Examples include lithium-ion secondary batteries, all-solid-state batteries, and electric double-layer capacitors. To provide functions such as maintaining or increasing the amount of incident light, a surface that is resistant to water and dirt, or a function to collect or guide light may be added.
[0093] [Mobile] The mobile body of the present disclosure has a photoelectric conversion element of the present disclosure. Figure 2 is a schematic perspective view showing one embodiment of a mobile body equipped with the photoelectric conversion element of the present disclosure. The mobile body 30 has a photoelectric conversion element 31 of the present disclosure and a body 32 equipped with the photoelectric conversion element 31. The photoelectric conversion element 31 is positioned in a location on the body 32 that can receive ambient light. If the mobile body 30 is an automobile, the photoelectric conversion element 31 may be placed on the roof. The electrical energy obtained by the photoelectric conversion element 31 may be used to power the mobile body 30 or other electrical equipment. The electrical energy generated from the power of the mobile body 30 may be used to power the photoelectric conversion element 31. If the mobile body 30 is an automobile, the frictional energy generated by the brakes may be converted into electrical energy and used to control the photoelectric conversion element 31.
[0094] The mobile body 30 may be, for example, an automobile, a motorcycle, a railway vehicle, a ship, a satellite, an airplane, or a drone. The structure of the mobile body 32 is not particularly limited, but it is preferably made of a high-strength material.
[0095] [Building materials] The building material of the present disclosure has a photoelectric conversion element of the present disclosure. Figure 3 is a schematic perspective view showing one embodiment of the building material equipped with the photoelectric conversion element of the present disclosure. The building material 40 may be the roof of a building. The building material 40 of this embodiment has a photoelectric conversion element 41 of the present disclosure, a protective member 42 for protecting the photoelectric conversion element 41, a heat dissipation member 43, and exterior parts 44a and 44b.
[0096] The building material 40 of this disclosure may have a heat dissipation member 43 with a higher thermal conductivity than the photoelectric conversion element 41. Generally, when a building material equipped with a photoelectric conversion element is used on a roof or the like, the temperature of the photoelectric conversion element 41 may rise due to sunlight, which may reduce the photoelectric conversion efficiency. In this case, the reduction in photoelectric conversion efficiency can be reduced by using a heat dissipation member 43. Examples of heat dissipation members 43 include metals, alloys, liquid metals, and liquid resins.
[0097] Furthermore, the building material 40 of this disclosure may have exteriors 44a and 44b. Exteriors 44a and 44b may emit different colors or the same color. 44a and 44b may be composed of the same material or different materials. As the exterior material, paint or a transparent substrate may be used, and it is preferable to use one that has low light absorption and high heat shielding properties.
[0098] In addition to the above examples of applications, the following are some other examples of applications: Portable devices include calculators, sensors, and small solar panels. Wearable devices include eyeglasses, smartwatches, and portable medical devices. Sheet structures supported by multiple frames include tents, greenhouses, and truck beds. Fixed structures include road panels, floating panels, building materials that utilize the flexibility of the substrate, wall-type building materials, glass-type building materials, and mega solar panels.
[0099] <Manufacturing method for photoelectric conversion elements> A method for manufacturing a photoelectric conversion element according to the present disclosure includes the steps of forming a first electrode, forming a second electrode, forming a photoelectric conversion layer containing a perovskite crystal between the first electrode and the second electrode, and forming a charge transport layer between the photoelectric conversion layer and the first electrode. The following describes each step of the manufacturing process.
[0100] [Steps for forming the first electrode and steps for forming the second electrode] In the process of forming the first electrode and the process of forming the second electrode, an appropriate method can be selected depending on the material of the first electrode and the material of the second electrode, respectively. Examples of such methods include, but are not limited to, sputtering vacuum deposition, CVD (vapor deposition), and SPD (spray pyrolysis deposition). The materials of the first and second electrodes are as described above. When either or both of the first and second electrodes are transparent electrodes, the thickness of the transparent electrode is preferably 0.03 μm or more and 3 μm or less. When manufacturing solar cells, cutting processes may be performed between each manufacturing step to form circuits. Examples of cutting processes include mechanical patterning and laser patterning.
[0101] [Modularization Process] The element, including the electrodes, may be sealed. The material used for sealing is not limited to organic or inorganic materials. Specifically, examples include silicone rubber, resins having a siloxane skeleton, resins containing fluorine, silazane, and glass. Examples of sealing methods include coating, vapor deposition, or sealing by attaching a sheet. Furthermore, from the viewpoint of suppressing adhesion between elements that occurs when winding in a roll-to-roll manner, the surface of the sealed elements may be given a hairline finish.
[0102] [Process for forming the photoelectric conversion layer] The photoelectric conversion layer formation process may include a step of applying a liquid containing the above-mentioned photoelectric conversion layer material. Examples of application methods include spin coating, blade coating, slit die coating, screen printing, bar coating, mold making, print transfer, immersion and pull-up, inkjet, spray, and vacuum deposition.
[0103] From these options, a suitable choice is made depending on the characteristics of the photoelectric conversion layer to be fabricated, such as thickness control and orientation control. Annealing may be performed under reduced pressure or in an inert atmosphere (nitrogen or argon atmosphere) to remove the solvent or dispersion medium from the liquid containing the material of the applied photoelectric conversion layer.
[0104] The annealing temperature is preferably between 40°C and 300°C, and more preferably between 50°C and 150°C. Annealing is preferable because it can increase the contact area at the interface between the stacked layers, as the materials constituting each layer penetrate each other, thereby increasing the current.
[0105] [Process for forming a charge transport layer] A preferred method for forming the charge transport layer is to apply a liquid containing the charge transport layer material described above. Examples of application methods include spin coating, blade coating, slit die coating, screen printing, bar coating, molding, print transfer, immersion and pull-up, inkjet, spray, and vacuum deposition. [Examples]
[0106] The present disclosure will be described in more detail below using examples and comparative examples. The present disclosure is not limited in any way by the following examples unless it exceeds the gist of the disclosure. In the following examples, "parts" refers to mass unless otherwise specified.
[0107] <Preparation of Particle 1> Process (1) Under a nitrogen flow atmosphere, 5.46 parts of orthophthalonitrile and 45 parts of α-chloronaphthalene were added to the reaction vessel, which was then heated to a temperature of 30°C and maintained at that temperature. Next, 3.75 parts of gallium trichloride were added at this temperature (30°C). The water concentration of the mixture at the time of addition was 150 ppm.
[0108] The temperature was then raised to 200°C. Next, the reaction was carried out at 200°C for 4.5 hours under a nitrogen flow atmosphere, then cooled, and the product was filtered when the temperature reached 150°C. The obtained filtrate was dispersed and washed with N,N-dimethylformamide at 140°C for 2 hours, and then filtered. The obtained filtrate was washed with methanol and dried to obtain chlorogallium phthalocyanine particles in a yield of 71%.
[0109] Process (2) 4.65 parts of the chlorogallium phthalocyanine particles were dissolved in 139.5 parts of concentrated sulfuric acid at 10°C, and the mixture was dropped dropwise into 620 parts of ice water under stirring to reprecipitation. The mixture was then filtered under reduced pressure using a filter press. A No. 5C filter (manufactured by Advantec Co., Ltd.) was used for this process.
[0110] The obtained wet cake (filtrate) was dispersed and washed with 2% ammonia water for 30 minutes, and then filtered using a filter press. Next, the obtained wet cake (filtrate) was dispersed and washed with deionized water, and the filtration process using a filter press was repeated three times.
[0111] Finally, freeze-drying was performed to obtain hydroxygallium phthalocyanine particles (hydrated hydroxygallium phthalocyanine particles) with a solid content of 23% by mass in a yield of 71%. These hydroxygallium phthalocyanine particles were dried using a hyper-dry dryer (product name: HD-06R, frequency (oscillation frequency): 2455MHz ± 15MHz, manufactured by Nippon Biocon) to obtain hydroxygallium phthalocyanine (OHGaPc) particles (crystals) with a moisture content of 1.0% by mass or less.
[0112] Process (3) Five parts of the hydroxygallium phthalocyanine particles were mixed with five parts of N-methylformamide solvent. This mixture was dispersed for six hours using a sand mill (TSG-1 / 4G-4U, manufactured by Igarashi Machinery Manufacturing Co., Ltd. (now AIMEX), with a disc diameter of 70 mm and five discs) containing five glass beads, and then filtered and dried to obtain particle 1.
[0113] <Preparation of resin solution 1> 1.0 g of polyvinyl acetal resin (product name: BM-2, manufactured by Sekisui Chemical Co., Ltd., glass transition temperature 71°C) was dissolved in 19 g of 2-propanol with stirring for 24 hours to obtain resin solution 1.
[0114] <Preparation of resin solution 2> 1.0 g of polymethyl methacrylate (trade name: PMMA, manufactured by Sigma-Aldrich, glass transition temperature 100°C) was dissolved in 19 g of chlorobenzene with stirring for 24 hours to obtain resin solution 2.
[0115] (Example 1) The photoelectric conversion element of Example 1 was obtained using the formation method described below. [Formation of the electron transport layer] An ITO-coated glass substrate was cleaned, and tin(II) oxide adjusted to 3% by mass was applied thereon by spin coating. The substrate was then heated at 150°C for 30 minutes to form an electron transport layer on a thin film with a thickness of 15 nm.
[0116] [Formation of the photoelectric conversion layer] 22.4 mg of methylammonium bromide, 172 mg of formamidium iodide, and 576 mg of lead iodide were dissolved in 600 μL of N,N-dimethylformamide and 160 μL of dimethyl sulfoxide, and the mixture was stirred for 1 hour (Solution 1). Furthermore, 389.72 mg of cesium iodide was dissolved in 1000 μL of dimethyl sulfoxide, and the mixture was stirred for 1 hour (Solution 2).
[0117] Subsequently, 40 μL of dissolved cesium iodide solution (Solution 2) was added to Solution 1 to prepare a photoelectric conversion layer coating solution. By spin-coating this coating solution onto the electron transport layer, Cs 0.05 (Fa 0.83 MA0.17 ) 0.96 Pb(I 0.95 Br 0.05 A 500 nm thick photoelectric conversion layer consisting of )3 was formed.
[0118] [Formation of a charge transport layer] 0.1 g of the aforementioned particles, 0.01 g of a calixarene compound (Japanese Patent Publication No. 2003-207913), 0.01 g of trioctylmethylammonium-bis(trifluoromethanesulfonyl)imide, and 10.6 g of 2-propanol were mixed together. 11 g of zirconia beads were then enclosed in this mixture, and the mixture was dispersed in a paint shaker (manufactured by Toyo Seiki) for 3 hours.
[0119] Subsequently, 0.2 g of resin solution 1 was added, and paint shaker dispersion was performed again for 4 hours. A charge transport layer with a thickness of 150 nm was formed by spin coating this charge transport layer solution onto the photoelectric conversion layer.
[0120] [Hole transport layer formation] 0.15 g of the compound represented by the following formula (HTM-1) and 0.015 g of diphenyleneiodonium-tris(pentafluorophenyl)borane were weighed out and dissolved in chlorobenzene. This was then coated onto the charge transport layer by spin coating to form a 200 nm thick hole transport layer. [ka]
[0121] [Formation of the first electrode] On the aforementioned hole transport layer, a layer with a thickness of 80 nm and an area of 0.09 cm² 2 A gold electrode was formed by vacuum deposition to obtain a photoelectric conversion element.
[0122] (Example 2) A photoelectric conversion element was obtained in the same manner as in Example 1, except that the charge transport layer and the surface modification layer were formed as described below. A hole transport layer was formed on the surface modification layer.
[0123] [Formation of a charge transport layer] 0.1 g of the aforementioned particles 1 and 0.01 g of a calixarene compound (Japanese Patent Publication No. 2003-207913) were mixed with 10.6 g of 2-propanol, 11 g of zirconia beads were enclosed in this mixture, and the mixture was dispersed in a paint shaker (manufactured by Toyo Seiki) for 3 hours.
[0124] Subsequently, 0.2 g of resin solution 1 was added, and paint shaker dispersion was performed again for 4 hours to prepare the charge transport layer solution. A charge transport layer with a thickness of 150 nm was formed by spin coating this charge transport layer solution onto the photoelectric conversion layer.
[0125] [Formation of a surface-modified layer] 0.143 g of diphenyleneiodonium-bis(trifluoromethanesulfonyl)imide was mixed and dissolved with 1.1 g of monochlorobenzene to obtain a surface modification layer coating. A 1 nm surface modification layer was formed by spin-coating this surface modification layer coating onto the charge transport layer.
[0126] (Example 3) A photoelectric conversion element was obtained in the same manner as in Example 1, except that the cyclic conjugated compound was replaced with oxytitanium phthalocyanine particles.
[0127] (Example 4) A photoelectric conversion element was obtained in the same manner as in Example 1, except that the calixarene compound was changed to the calix[4]arene represented by the following formula (CA-1). [ka]
[0128] (Example 5) In Example 1, a photoelectric conversion element was obtained in the same manner as in Example 1, except that resin solution 1 was changed to resin solution 2.
[0129] (Examples 6-46) In Example 1, a photoelectric conversion element was obtained in the same manner as in Example 1, except that the mass portions of the cyclic conjugated compound, the calixarene compound, the compound that improves current density, and the resin solution were changed as shown in Table 2.
[0130] (Examples 47-51) In Example 2, a photoelectric conversion element was obtained in the same manner as in Example 2, except that the surface modification layer was changed as shown in Table 2.
[0131] (Comparative Example 1) In Example 2, a photoelectric conversion element was obtained in the same manner as in Example 2, except that a surface modification layer was not formed.
[0132] [evaluation] The photoelectric conversion efficiency of the photoelectric conversion elements obtained in Examples 1 to 51 and Comparative Example 1 was measured. The measurement result for Example 1 was set to 100, and the relative values are shown in Table 2 below.
[0133] [Table 2-1]
[0134] [Table 2-2]
[0135] This embodiment includes the following configuration. (Composition 1) A first electrode, a second electrode, and a photoelectric conversion layer containing a perovskite crystal disposed between the first electrode and the second electrode. A photoelectric conversion element having, A charge transport layer is provided between the photoelectric conversion layer and the first electrode. The charge transport layer comprises a cyclic conjugated compound in which multiple pyrrole rings are conjugated together, and a calixarene compound. A photoelectric conversion element characterized in that the charge transport layer contains a compound that improves current density, or the photoelectric conversion element has a surface modification layer between the charge transport layer and the first electrode. (Configuration 2) The photoelectric conversion element according to configuration 1, wherein the cyclic conjugated compound is a pigment. (Composition 3) The photoelectric conversion element according to configuration 1 or 2, wherein the cyclic conjugated compound is a phthalocyanine compound. (Composition 4) The photoelectric conversion element according to any one of configurations 1 to 3, wherein the cyclic conjugated compound is a compound having the structure shown by the following formula (Pc-1). [ka] (In the above formula (Pc-1), M is preferably H2, a metal atom with a ligand, or a metal atom without a ligand.) (Composition 5) The photoelectric conversion element according to configuration 4, wherein M is gallium, aluminum, titanium, iron, or silicon having a ligand. (Composition 6) The photoelectric conversion element according to any one of configurations 1 to 5, wherein the cyclic conjugated compound is a hydroxygallium compound or a chlorogallium phthalocyanine compound. (Composition 7) The calixarene compound is represented by the following formula (A) in the photoelectric conversion element according to any one of configurations 1 to 6. [ka] (In the above formula (A), R 1 ~R 5 This is done independently within each repeating unit, and independently for each of the n repeating units, R 1 R represents a hydrogen atom or an alkyl group. 2 R represents a substituted or unsubstituted alkylene group. 3 ~R 5 This represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted -Y-Ar group, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted heterocyclic group. R 3 ~R 5At least one of these is a substituted -Y-Ar group. The -Y- represents -CH=N-, -CH=CH-, or -N=N-, and the Ar is a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted heterocyclic group. n is an integer between 3 and 20. (Composition 8) The photoelectric conversion element according to configuration 7, wherein n is 4 or 8. (Composition 9) The aforementioned R 4 The photoelectric conversion element according to configuration 7 or 8, wherein each of the n repeating units is independently a nitrophenylazo group or a dinitrophenylazo group. (Composition 10) The photoelectric conversion element according to any one of configurations 1 to 9, wherein the molecular weight of the calixarene compound is 10,000 or less. (Composition 11) A photoelectric conversion element according to any one of configurations 1 to 10, wherein the calixarene compound is a mixture of the compound represented by the following formula (C-1), the compound represented by the following formula (C-2), the compound represented by the following formula (C-3), and the compound represented by the following formula (C-4). [ka] [ka] [ka] [ka] (Composition 12) The photoelectric conversion element according to any one of configurations 1 to 11, wherein the compound that improves the current density is a dopant material or an ionic liquid material. (Composition 13) A photoelectric conversion element according to any one of configurations 1 to 12, wherein the ratio of the mass of the compound that improves the current density to the mass of the calixarene compound is 0.002 or more and 10 or less. (Composition 14) A photoelectric conversion element according to any one of configurations 1 to 13, wherein the ratio of the mass of the calixarene compound to the mass of the cyclic conjugated compound is 0.01 or more and 0.5 or less. (Composition 15) The photoelectric conversion element according to configurations 1 to 14, wherein the ratio of the mass of the compound that improves the current density to the mass of the cyclic conjugated compound is 0.0001 or more and 1 or less. (Composition 16) The photoelectric conversion element according to any one of configurations 1 to 15, wherein the charge transport layer contains a resin. (Composition 17) The photoelectric conversion element according to configuration 16, wherein the resin is an insulating resin. (Composition 18) The photoelectric conversion element according to configuration 16 or 17, wherein the ratio of the mass of the calixarene compound to the mass of the resin is 0.2 or more and 10 or less. (Composition 19) A photoelectric conversion element according to any one of configurations 16 to 18, wherein the ratio of the mass of the compound that improves the current density to the mass of the resin is 0.002 or more and 10 or less. (Composition 20) The photoelectric conversion element according to any one of claims 16 to 19, wherein the ratio of the mass of the cyclic conjugated compound to the mass of the resin is 5 or more and 30 or less. (Composition 21) The photoelectric conversion element according to any one of configurations 1 to 20, wherein the surface modification layer comprises a dopant material, an ionic liquid material, or a passivation material. (Composition 22) A photoelectric conversion device having a photoelectric conversion element described in any one of configurations 1 to 21. (Composition 23) A mobile body having a photoelectric conversion element described in any one of configurations 1 to 21. (Composition 24) A building material having a photoelectric conversion element as described in any one of configurations 1 to 21. (Composition 25) Pigments are cyclic conjugated compounds in which multiple pyrrole rings are conjugated together, Calixarene compounds and Solvents and, Compounds that improve current density, or compounds that form a surface modification layer. A composition containing the following: [Explanation of symbols]
[0136] 1. Photoelectric conversion element 2 circuit boards 3 Second electrode 4 Electron transport layer 5 Photoelectric conversion layer 6 Charge transport layer 7 First electrode
Claims
1. A first electrode, a second electrode, and a photoelectric conversion layer containing a perovskite crystal disposed between the first electrode and the second electrode. A photoelectric conversion element having, A charge transport layer is provided between the photoelectric conversion layer and the first electrode. The charge transport layer comprises a cyclic conjugated compound in which multiple pyrrole rings are conjugated together, and a calixarene compound. A photoelectric conversion element characterized in that the charge transport layer contains a compound that improves current density, or the photoelectric conversion element has a surface modification layer between the charge transport layer and the first electrode.
2. The photoelectric conversion element according to claim 1, wherein the cyclic conjugated compound is a pigment.
3. The photoelectric conversion element according to claim 1, wherein the cyclic conjugated compound is a phthalocyanine compound.
4. The photoelectric conversion element according to claim 1, wherein the cyclic conjugated compound is a compound having the structure shown in the following formula (Pc-1). 【Chemistry 1】 (In the above formula (Pc-1), M is H 2 (Preferably, metal atoms having ligands or metal atoms without ligands.)
5. The photoelectric conversion element according to claim 4, wherein M is gallium, aluminum, titanium, iron, or silicon having a ligand.
6. The photoelectric conversion element according to claim 1, wherein the cyclic conjugated compound is a hydroxygallium compound or a chlorogallium phthalocyanine compound.
7. The photoelectric conversion element according to claim 1, wherein the calixarene compound is represented by the following formula (A). 【Chemistry 2】 (In the above formula (A), R 1 ~R 5 R is independent within each repeating unit and independently for each of the n repeating units. 1 R represents a hydrogen atom or an alkyl group. 2 R represents a substituted or unsubstituted alkylene group. 3 ~R 5 This represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted -Y-Ar group, a substituted or unsubstituted aromatic hydrocarbon group, or a substituted or unsubstituted heterocyclic group. R 3 to R 5 Among them, at least one is a -Y-Ar group having a substituent. The -Y- represents -CH=N-, -CH=CH-, or -N=N-, and the Ar is a substituted or unsubstituted aromatic hydrocarbon group or a substituted or unsubstituted heterocyclic group. n is an integer of 3 or more and 20 or less.)
8. The photoelectric conversion element according to claim 7, wherein n is 4 or 8.
9. The aforementioned R 4 The photoelectric conversion element according to claim 7, wherein each of the n repeating units is independently a nitrophenylazo group or a dinitrophenylazo group.
10. The photoelectric conversion element according to claim 1, wherein the molecular weight of the calixarene compound is 10,000 or less.
11. The photoelectric element according to claim 1, wherein the calixarene compound is a mixture of the compound represented by the following formula (C-1), the compound represented by the following formula (C-2), the compound represented by the following formula (C-3), and the compound represented by the following formula (C-4). 【Transformation 3】 【Chemistry 4】 【Transformation 5】 【Transformation 6】
12. The photoelectric conversion element according to claim 1, wherein the compound that improves the current density is a dopant material or an ionic liquid material.
13. The photoelectric conversion element according to claim 1, wherein the ratio of the mass of the compound that improves the current density to the mass of the calixarene compound is 0.002 or more and 10 or less.
14. The photoelectric conversion element according to claim 1, wherein the ratio of the mass of the calixarene compound to the mass of the cyclic conjugated compound is 0.01 or more and 0.5 or less.
15. The photoelectric conversion element according to claim 1, wherein the ratio of the mass of the compound that improves the current density to the mass of the cyclic conjugated compound is 0.0001 or more and 1 or less.
16. The photoelectric conversion element according to claim 1, wherein the charge transport layer contains a resin.
17. The photoelectric conversion element according to claim 16, wherein the resin is an insulating resin.
18. The photoelectric conversion element according to claim 16, wherein the ratio of the mass of the calixarene compound to the mass of the resin is 0.2 or more and 10 or less.
19. The photoelectric conversion element according to claim 16, wherein the ratio of the mass of the compound that improves the current density to the mass of the resin is 0.002 or more and 10 or less.
20. The photoelectric conversion element according to claim 16, wherein the ratio of the mass of the cyclic conjugated compound to the mass of the resin is 5 or more and 30 or less.
21. The photoelectric conversion element according to claim 1, wherein the surface modification layer comprises a dopant material, an ionic liquid material, or a passivation material.
22. A photoelectric conversion device having a photoelectric conversion element according to any one of claims 1 to 21.
23. A mobile body having a photoelectric conversion element according to any one of claims 1 to 21.
24. A building material having a photoelectric conversion element according to any one of claims 1 to 21.
25. Pigments are cyclic conjugated compounds in which multiple pyrrole rings are conjugated together, Calixarene compounds and Solvents and, Compounds that improve current density, or compounds that form a surface modification layer A composition containing the following:
Citation Information
Patent Citations
Solar cell
JP2018082140A
Photoelectric conversion element
JP2024060579A