Organic-inorganic composite material, method for producing organic-inorganic composite material, circularly-polarized light detection element, device, and method

Abstract

This organic-inorganic composite material comprises a chiral molecule and a plurality of inorganic chains formed from a perovskite-type substance and constituting a chain-shaped structure, wherein the chiral molecule is included in at least part of a boundary portion between adjacent chains of the inorganic chains; the perovskite-type substance and the chiral molecules constitute A3B2X9 or ABX3 composed of three kinds of ions A, B, and X; and a trivalent metal ion is included as the ion B.

Description

Organic-inorganic composite material, method for producing organic-inorganic composite material, circularly polarized light detection element, device, and method

[0001] The present invention relates to an organic-inorganic composite material, a manufacturing method thereof, a circular polarization detection element, a device, and a method. This application claims priority based on Japanese Patent Application No. 2024-099800, filed on June 20, 2024, the contents of which are incorporated herein by reference.

[0002] Polarization image sensors are known that utilize polarization phenomena to visualize information such as the structure and properties of various objects. A polarization image sensor includes a polarizer array with multiple groups of four polarizers with different polarization directions, and a photodiode array consisting of multiple photodiodes arranged facing each polarizer group. Linearly polarized light signals transmitted through the four polarizers in the same group are converted into electrical signals by the photodiodes and output as information for one pixel. From the linearly polarized light output signal, three Stokes parameters can be calculated by combining the sum and difference of the intensities of orthogonal polarization components, and these parameters can be used to quantify the state of the transmitted light.

[0003] However, it is difficult to visualize states such as birefringence and stress distribution observed when an object is bent using only the three Stokes parameters obtained from linearly polarized light. It is known that these states can be visualized using Stokes parameters calculated from the intensity of circularly polarized light, and a technology for detecting circularly polarized light is needed. Furthermore, detecting circularly polarized light using the polarization image sensor described above requires an additional wave plate, which significantly reduces sensitivity. Therefore, a technology for directly detecting circularly polarized light is needed.

[0004] Patent Document 1 discloses a thin film made of a perovskite-type material, the thin film comprising a plurality of inorganic layers constituting a layered structure and / or a plurality of inorganic chains constituting a chain structure, and chiral molecules contained in at least a portion of the boundaries between adjacent inorganic layers and / or adjacent inorganic chains, the chiral molecules being either S-chiral molecules or R-chiral molecules, or the abundance ratio of either is higher than the abundance ratio of the other, and the crystalline structure of the perovskite-type material being oriented in a predetermined direction. It is also disclosed that the thin film is capable of directly detecting circularly polarized light.

[0005] International Publication No. 2021 / 241554

[0006] In order to use an organic-inorganic composite material containing a perovskite-type substance as a circular polarization detection element, there is a demand for an organic-inorganic composite material that enables direct detection of circularly polarized light in the long wavelength region, and in particular, that further improves the CD signal in the visible region by imparting CD absorption properties in the visible region, and a method for producing the same.

[0007] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide an organic-inorganic composite material that enables direct detection of circularly polarized light in the long wavelength range, and in particular, further improves the CD signal in the visible range by imparting CD absorbency in the visible range, a method for producing the organic-inorganic composite material, a circular polarization detection element including the organic-inorganic composite material, a device including the circular polarization detection element, and a method for directly detecting circularly polarized light in the long wavelength range using a circular polarization detection device that uses the organic-inorganic composite material.

[0008] In order to solve the above problems, the present invention has the following aspects: [1] An organic-inorganic composite material for detecting circularly polarized light, comprising a perovskite-type substance, a plurality of inorganic chains each having a chain structure, and chiral molecules, the chiral molecules being contained in at least a portion of the boundary between adjacent inorganic chains, the chiral molecules being either S-type chiral molecules or R-type chiral molecules, or the abundance ratio of either is higher than the abundance ratio of the other, the crystal structure of the perovskite-type substance being oriented in a certain direction, and the perovskite-type substance and the chiral molecules being oriented in an A-type chiral molecule composed of three types of ions A, B, and X. ３ B ２ X ９ or ABX ３an organic-inorganic composite material comprising: the ion B and the ion X forming a plurality of unit units each having an octahedral structure; the octahedral structures of adjacent unit units sharing one face to form a face-sharing oligomer structure; and a trivalent metal ion as the ion B. [2] The organic-inorganic composite material according to [1], comprising only a trivalent metal ion as the ion B; the face-sharing oligomer structure being a face-sharing dimer structure consisting of two of the unit units; and the inorganic chain being composed of a chain structure formed by the face-sharing dimers being oriented without sharing any vertex or face. [3] The organic-inorganic composite material according to [1], wherein the ion B contains a trivalent metal ion and another metal ion different from the trivalent metal ion, the molar ratio of the trivalent metal ion to the other metal ion being 10:90 to 1:99, the face-sharing oligomer structure is a face-sharing oligomer structure containing three or more of the unit units, and the inorganic chain is composed of a chain structure of the face-sharing oligomer. [4] The organic-inorganic composite material according to [1], wherein the ion B contains only a trivalent metal ion, the face-sharing oligomer structure is a face-sharing oligomer structure containing three or more of the unit units, and the inorganic chain is composed of a chain structure of the face-sharing oligomer. [5] The organic-inorganic composite material according to any one of [1] to [4], wherein the trivalent metal ion is a bismuth ion. [6] The organic-inorganic hybrid material according to [3], wherein the molar ratio of the trivalent metal ions to the other metal ions is 5:95 to 1:99. [7] The organic-inorganic hybrid material according to [3], [5], or [6], wherein the other metal ions are lead ions or tin ions. [8] The organic-inorganic hybrid material according to any one of [1] to [7], wherein the ions A are aromatic compounds containing ethylammonium ions. [9] The organic-inorganic hybrid material according to [8], wherein the aromatic compound is a polycyclic aromatic compound.

[10] The organic-inorganic hybrid material according to [9], wherein the aromatic rings of the polycyclic aromatic compounds are naphthalene rings or anthracene rings.

[11] The organic-inorganic composite material according to any one of [1] to

[10] , having a surface roughness Ra of 1 nm or more and 30 nm or less.

[0009]

[12] A method for producing an organic-inorganic composite material according to [2], comprising the steps of: a first solution preparation step of dissolving an oxide or halide of the ion B in a solvent while heating the solvent to obtain a first solution; a halide synthesis step of synthesizing a halide AX, which is a chiral molecule composed of the ion A and the ion X; a second solution preparation step of dissolving the halide AX in the first solution while heating the first solution to obtain a second solution; a crystal formation step of precipitating a crystal by gradually cooling the second solution, the crystal being composed of a precursor of a perovskite-type substance; and a drying treatment of the obtained crystal to obtain the chiral molecule halide AX of the ion A. ３ B ２ X ９

[13] The method for producing an organic-inorganic composite material according to [2], comprising: a first solution preparation step of dissolving an oxide or halide of the ion B in a solvent while heating the solvent to obtain a first solution, a halide synthesis step of synthesizing a halide AX that is a chiral molecule composed of the ion A and the ion X, a second solution preparation step of dissolving the halide AX in the first solution while heating the first solution to obtain a second solution, and a coating film formation step of applying the second solution onto a substrate by a spin coating method to form a coating film on the substrate that is composed of a precursor of a perovskite-type substance.

[14] A method for producing an organic-inorganic composite material according to [3], comprising the steps of: preparing a solution 1a by dissolving BX, a raw material for a precursor of a perovskite-type substance composed of the ion B and the ion X, in a solvent while heating the solvent to obtain a solution 1a; synthesizing a halide AX, a chiral molecule composed of the ion A and the ion X; preparing a solution 2a by dissolving the halide AX in the solution 1a while heating the solution 1a to obtain a solution 2a; applying the solution 2a onto a substrate by a spin coating method to form a coating film composed of a precursor of a perovskite-type substance on the substrate; and heating the obtained coating film to form a coating film of the precursor of the perovskite-type substance, the coating film being a 1a-type compound. ３

[15] The method for producing an organic-inorganic composite material according to [4], comprising: a solution 1a preparation step of dissolving BX, a raw material for a precursor of a perovskite-type substance composed of the ions B and X, in a solvent while heating the solvent to obtain a solution 1a; a halide synthesis step of synthesizing a halide AX, a chiral molecule composed of the ions A and X, in the solution 1a while heating the solution 1a to obtain a solution 2a; a coating film formation step of applying the solution 2a onto a substrate by a spin coating method to form a coating film composed of a precursor of the perovskite-type substance on the substrate; and a method for producing an organic-inorganic composite material having the above-mentioned ABX by heating the solvent. ３ and forming an organic-inorganic composite material having the formula (16).

[16] The method for producing an organic-inorganic composite material according to any one of

[12] to

[15] , wherein the trivalent metal ion is a bismuth ion.

[17] The method for producing an organic-inorganic composite material according to

[14] , wherein the other metal ion is a lead ion or a tin ion.

[0010]

[18] A circular polarization detection element comprising the organic-inorganic composite material according to any one of [1] to

[11] .

[19] The circular polarization detection element according to

[18] , which is formed by laminating a negative electrode layer, the organic-inorganic composite material, and a positive electrode layer in this order, and at least one of the negative electrode layer and the positive electrode layer is optically transparent.

[20] A device incorporating the circular polarization detection element according to

[18] .

[21] A device incorporating the circular polarization detection element according to

[19] .

[0011]

[22] A method for directly detecting circularly polarized light in the long wavelength range using a circular polarization detector, the method comprising a step of placing the organic-inorganic composite material according to any one of [1] to

[11] as a light-receiving layer of the circular polarization detector.

[23] Use of the organic-inorganic composite material according to any one of [1] to

[11] for circular polarization detection.

[0012] According to the present invention, it is possible to provide an organic-inorganic composite material that enables direct detection of circularly polarized light in a longer wavelength range, a method for producing the organic-inorganic composite material, a circular polarization detection element that includes the organic-inorganic composite material, a device that includes the circular polarization detection element, and a method for directly detecting circularly polarized light in a longer wavelength range using a circular polarization detection device that uses the organic-inorganic composite material.

[0013] 4 is a schematic diagram of a unit having an octahedral structure formed by ions B and X. FIG. 4 is a schematic diagram of an inorganic chain included in an organic-inorganic composite material according to one embodiment of the present invention. FIG. 4 is a partially enlarged view limited to a chain-type structure (i.e., a chain structure) consisting of a face-sharing oligomer structure formed from four octahedral unit units. FIG. 4 is a schematic diagram of an inorganic chain included in an organic-inorganic composite material according to one embodiment of the present invention. FIG. 4 is a partially enlarged view limited to a pseudo-chain structure (i.e., a chain-like structure) consisting of two pairs of face-sharing oligomer structures (face-sharing dimer structures) formed from two octahedral unit units. FIG. 4 is a schematic diagram of a circular polarization detection element according to one embodiment of the present invention. The upper view of FIG. 4 shows a case where the face-sharing oligomer structure includes three or more octahedral unit units, and the lower view of FIG. 4 shows a case where the face-sharing oligomer structure is a face-sharing dimer structure consisting of two octahedral unit units. 5 shows the circular dichroism spectrum (upper panel of FIG. 5 ) and the optical absorption spectrum (lower panel of FIG. 5 ) of the organic-inorganic composite materials of Comparative Examples 1 and 2 (i.e., organic-inorganic composite materials not containing a bismuth ion, which is a trivalent metal ion, as the ion B). 6 shows the circular dichroism spectrum (upper panel of FIG. 6 ) and the optical absorption spectrum (lower panel of FIG. 6 ) of the organic-inorganic composite material of Example 2. 7 shows the circular dichroism spectrum (upper panel of FIG. 7 ) and the optical absorption spectrum (lower panel of FIG. 7 ) of the organic-inorganic composite material of Example 3. 8 shows the XDR pattern of the organic-inorganic composite material of Example 3. 9 shows the circular dichroism spectrum (upper panel of FIG. 9 ) and the optical absorption spectrum (lower panel of FIG. 9 ) of the organic-inorganic composite material of Example 1. 10 shows a schematic diagram of an inorganic chain included in an organic-inorganic composite material according to one embodiment of the present invention. 11 shows a partially enlarged view of a pseudo-chain structure (i.e., a chain-like structure) consisting of four pairs of face-sharing oligomer structures (face-sharing dimer structures) formed from unit units having two octahedral structures.The left diagram in the figure shows a pseudo-chain structure when the perovskite structure is a chiral structure with an S configuration, the center diagram shows a pseudo-chain structure when the perovskite structure is a chiral structure with an R configuration, the upper diagram on the right diagram shows a face-sharing dimer structure consisting of two unit units having an octahedral structure with a chiral perovskite structure with an S configuration, and the lower diagram on the right diagram shows a face-sharing dimer structure consisting of two unit units having an octahedral structure with a chiral perovskite structure with an R configuration.

[0014] The following describes in detail the embodiments of the present invention. However, the following description is merely an example of an embodiment of the present invention, and the present invention is not limited to these details and can be modified and implemented within the scope of its gist. The drawings used in the following description may show characteristic portions enlarged for convenience in order to make the features easier to understand, and the dimensional ratios of each component may not necessarily be the same as in reality. Furthermore, the materials, dimensions, etc. exemplified in the following description are merely examples, and the present invention is not limited to these and can be modified as appropriate within the scope of its gist.

[0015] Organic-Inorganic Composite Material The organic-inorganic composite material of this embodiment is an organic-inorganic composite material for detecting circularly polarized light. The organic-inorganic composite material includes a plurality of inorganic chains and chiral molecules, and the chiral molecules are contained in at least a portion of the boundaries between adjacent inorganic chains. The inorganic chains are made of a perovskite-type substance and are configured as chain structures. Specific examples of the chain structures include chain structures and chain-like structures. Here, the chain-like structure refers to a pseudo-chain structure (for example, a structure in which perovskite-type substances are arranged in a specific direction (arrangement direction) as shown in FIG. 3). In the present invention, the term "chain-like structure" or "pseudo-chain structure" basically refers only to a chain structure formed from a face-sharing dimer consisting of two unit units described below (hereinafter, sometimes simply referred to as a "face-sharing dimer structure"). On the other hand, a chain structure formed from a face-sharing dimer structure containing three or more unit units described below is referred to as a "chain structure." The chain-like structure (pseudo-chain structure) and the chain structure can be identified from the XRD pattern obtained by XRD measurement, which will be described later. For example, they can be identified by the presence or absence of a peak corresponding to the 011 plane (the period of a face-sharing dimer consisting of two units) at a diffraction angle (2θ) of approximately 5°, or the presence or absence of a peak corresponding to the 002 plane (between primary helical chains) at a diffraction angle (2θ) of approximately 7°. Furthermore, by measuring the CD signal in the visible region, it can be identified by the presence or absence of an improvement in the CD signal (without R and S inversion) due to the CD absorption of the face-sharing dimer, or the presence or absence of an improvement in the CD signal (with R and S inversion) due to the CD absorption of the primary helical chain. The chiral molecules may contain only either S-chiral molecules or R-chiral molecules. When both S-chiral molecules and R-chiral molecules are contained, the abundance ratio (molar ratio) of one is higher than the abundance ratio of the other. The crystal structure of the perovskite-type material is oriented in a certain direction. Here, "oriented in a certain direction" means, for example, that the perovskite-type substance and the chiral molecule are present in a substantially regular and uniform state in a direction determined within a specific range. ３ B ２ X９ or ABX ３ As shown in FIG. 1 , the ions B and X form a plurality of units each having an octahedral structure. In the chain structure of this embodiment, the octahedral structures of adjacent units share one face to form an oligomer structure. The ions B in the octahedral structure contain a trivalent metal ion.

[0016] 2 and 3 are schematic diagrams illustrating the configuration of an organic-inorganic composite material 200 (300) according to this embodiment. The organic-inorganic composite material 200 (300) is an organic-inorganic composite material for detecting circularly polarized light, and is a chiral organic-inorganic composite material composed of a perovskite-type substance. The organic-inorganic composite material 200 (300) is primarily composed of a perovskite-type substance 201 (301), and includes multiple inorganic chains 202 (302) composed of a chain structure and chiral molecules 203 (303). A chain structure is preferable because it can increase the anisotropy factor compared to a layer structure. While FIGS. 2 and 3 illustrate the use of amino groups as the bonding functional groups of the chiral molecules 203 (302), the present invention is not limited to amino groups.

[0017] Each inorganic chain 202 (302) is composed of a chain structure with a diameter of about 1 nm, and is composed of compound A, which is composed of three types of ions A, B, and X. ３ B ２ X ９ or ABX ３ The perovskite-type material is composed of multiple perovskite-type materials that form a polycrystalline structure. The crystal structure of the perovskite-type material has a textured structure and is oriented in a certain direction. Specifically, ions B and X are arranged in a unit (BX) having an octahedral structure. ６ ) ｎ－and the octahedral structures of adjacent units share one face to form a face-sharing oligomer structure. When B contains only a trivalent metal ion, n is -3. When B contains a trivalent metal ion and a divalent metal ion, n is greater than -4 and less than -3. When B contains a trivalent metal ion, a divalent metal ion and / or a tetravalent metal ion, n is greater than -4 and less than -2 (the same applies below). Ion B is located at the center of the octahedron, and ion X is located at a vertex of the octahedron. Ion A is located at a position circumscribing the octahedral structure of each unit. Ion A is a chiral molecule 203 (303). That is, the perovskite-type substance and the chiral molecule 203 (303) form a compound A composed of three types of ions A, B, and X. ３ B ２ X ９ or ABX ３ Configure.

[0018] In the chain structure constituting the inorganic chain 202 in FIG. 2, the face-sharing oligomer structure is a face-sharing oligomer structure containing three or more of the unit units, and the composition of the compound composed of three types of ions A, B, and X is ABX ３ The inorganic chain 202 is composed of a chain structure formed by the orientation of the face-sharing oligomers. Here, the number of units contained in the face-sharing oligomer structure is not particularly limited as long as it is three or more. From a structural standpoint, the fewer the number of units, the more similar the structure becomes to a chain structure formed by a face-sharing dimer consisting of two of the unit units (i.e., a pseudo-chain structure), while the greater the number of units, the more similar the structure becomes to a chain structure formed by a face-sharing oligomer structure in which a large number of face-sharing dimers share one face with each other (i.e., a chain structure).

[0019] In the chain structure constituting the inorganic chain 302 in FIG. 3, the face-sharing oligomer structure is a face-sharing dimer structure consisting of two of the unit units, and the composition of the compound consisting of three types of ions A, B, and X is ３ B ２ X ９The inorganic chain 302 is composed of a chain structure formed by the plane-sharing dimers being oriented without sharing any vertex or plane.

[0020] The inorganic chains 202 (302) are arranged by octahedral structures sharing their faces, and chiral molecules 203 (303) surround the inorganic chains 202 (302). By sharing their faces with each other and containing a trivalent metal ion as ion B, as described below, it becomes possible to directly detect circularly polarized light in the long wavelength region, and in particular, it becomes possible to further improve the CD signal in the visible region by imparting CD absorption in the visible region.

[0021] Ion A is preferably an aromatic compound containing an alkylammonium ion. As the alkylammonium ion, alkylammonium ions having 2 to 4 carbon atoms are preferred, with ethylammonium ion, propylammonium ion, butylammonium ion, and isobutylammonium ion being more preferred, and ethylammonium ion being even more preferred. The aromatic compound has one or more aromatic monocyclic rings (i.e., benzene rings) forming an aromatic ring, preferably two or more, and more preferably three or more. That is, the aromatic compound is preferably a polycyclic aromatic compound. Examples of aromatic rings contained in the aromatic compound include a benzene ring, a naphthalene ring, and an anthracene ring. If the aromatic ring is an aromatic ring (fused aromatic ring) with a structure (covalent structure) that shares one side of the benzene ring, such as a naphthalene ring or an anthracene ring, this is preferred because it increases the circularly polarized light absorption intensity. Ion A preferably has a structure in which the carbon atom of the alkyl group of the alkylammonium ion is bonded to the aromatic ring.

[0022] Examples of the ion X include halogen ions. Examples of halogen ions include fluorine ions, chlorine ions, bromine ions, and iodine ions. The halogen ion is preferably an iodine ion.

[0023] The ion B contains a trivalent metal ion. Divalent metal ions such as lead ions and tin ions have been considered as the ion B in perovskite-type substances constituting organic-inorganic composite materials for detecting circularly polarized light. The inventors of the present application have discovered that by using a trivalent metal ion as the ion B, in a unit having an octahedral structure constituted by the ions B and X, the octahedral structures of adjacent units share one face to form a plurality of face-sharing oligomer structures. Furthermore, they have discovered that this face-sharing oligomer structure enables the organic-inorganic composite material to directly detect circularly polarized light in a longer wavelength range.

[0024] Ion B may contain only trivalent metal ions, or may contain trivalent metal ions and other metal ions different from the trivalent metal ions. The inventors of the present application have found through their investigations that when ion B contains only trivalent metal ions (e.g., bismuth ions), the face-sharing oligomer structure can be either of the following structures depending on the raw materials and production conditions of the organic-inorganic composite material: (1) a face-sharing dimer structure consisting of two of the unit units; or (2) a face-sharing oligomer structure containing three or more of the unit units. In the case of (1), this composition is A ３ B ２ X ９ On the other hand, in the case of (2), this composition is ABX ３ On the other hand, when ion B contains a trivalent metal ion and another metal ion (e.g., a lead ion) different from the trivalent metal ion, the face-sharing oligomer structure becomes a face-sharing oligomer structure containing three or more of the octahedral structures. In this case, the composition is ABX ３ This becomes:

[0025] When ion B contains only trivalent metal ions, in one embodiment of the present invention, inorganic chain 302 is composed of a chain structure formed by the face-sharing dimers orienting together without sharing any vertices or faces. It is believed that the face-sharing dimers interact with each other by crosslinking through the amino group portions of chiral molecules 303, thereby forming an inorganic chain. When ion B contains only trivalent metal ions, in yet another embodiment of the present invention, inorganic chain 202 is composed of a chain structure of the face-sharing oligomer. When ion B contains a trivalent metal ion and a metal ion different from the trivalent metal ion, inorganic chain 202 is composed of a chain structure of the face-sharing oligomer.

[0026] Examples of metal ions other than the trivalent metal ions include divalent metal ions. Preferred examples include lead ions and tin ions. More preferred examples include lead ions.

[0027] When ion B contains a trivalent metal ion and another metal ion different from the trivalent metal ion, the molar ratio of the trivalent metal ion to the other metal ion different from the trivalent metal ion, i.e., trivalent metal ion:other metal ion different from the trivalent metal ion, is preferably 10:90 to 1:99, and more preferably 5:90 to 1:99. When the molar ratio is within this range, a more stable face-sharing oligomer structure is likely to be formed.

[0028] The chiral molecule 203 (303) is included in at least a portion of the boundary 204 (304) between adjacent inorganic chains 202 (302), and is bonded to and fixed to the perovskite-type material on the surface of the inorganic chain 202 (302). More specifically, the chiral molecule 203 (303) is bonded to the perovskite-type material via a functional group covalently bonded to an asymmetric carbon atom constituting the chiral molecule 203 (303). This functional group is a substituent that can have an electric charge, and the substituent and the perovskite-type material can form a bond via a halogen ion. An example of the bonding functional group is an amino group. The amino group (NH３ ＋ ) is, for example, (BX ６ ) ｎ－ X － By combining with (BX ６ ) ｎ－ Chirality is generated in the inorganic chain consisting of (a) and (b), and a new circularly polarized light absorption ability is exhibited. The chiral molecule 203 (303) preferably has one or more aromatic monocyclic rings (i.e., benzene rings) forming an aromatic ring, and more preferably has two or more aromatic monocyclic rings. Furthermore, if the aromatic ring is an aromatic ring having a structure in which one side of the benzene ring is shared, such as a naphthalene ring or an anthracene ring, this is preferred because the circularly polarized light absorption intensity is increased.

[0029] The chiral molecule 203 (303) exists in an R-configuration and an S-configuration. The R-configuration or S-configuration chiral molecule 203 (303) strongly absorbs either right-handed or left-handed circularly polarized light. Here, an R-configuration is one in which four different bonding groups are bonded to the asymmetric carbon, with the one with the smallest atomic number placed furthest away and the remaining three bonding groups arranged clockwise from largest to smallest atomic number, and an S-configuration is one in which they are arranged counterclockwise. An example of an R-configuration is R-(+)-1-(1-naphthyl)ethylamine hydroiodide shown in the following formula (1). An example of an S-configuration is S-(-)-1-(1-naphthyl)ethylamine hydroiodide shown in the following formula (2).

[0030]

[0031]

[0032] When the chiral molecule 203 (303) reacts with 1.2 or more molecules of ion B, a layer structure (A ２ BX ４ On the other hand, when the chiral molecule 203 (303) reacts with ion B at a ratio of 0.75 molecules or less, a chain structure (ABX ３ or A ３ B ２ X ９When the chiral molecule 203 (303) reacts with one molecule of ion B at a ratio of more than 0.75 molecules and less than 1.2 molecules, a structure in which a chain structure and a layer structure are mixed is usually formed. In the case of a structure in which a chain structure and a layer structure are mixed, the perovskite-type substance and the chiral molecule react with compound A, which is composed of three types of ions A, B, and X. ２ BX ４ And, ABX ３ or A ３ B ２ X ９ The organic-inorganic composite material of this embodiment is an organic-inorganic composite material obtained by the reaction of 0.75 or less molecules of the chiral molecule 203 (303) with one molecule of the ion B.

[0033] The ions A, B, and X are as described above. The circularly polarized light absorption ability can be adjusted by adjusting the ratio of the chiral molecules 203 (303) and the ions B of the inorganic chains 202 (302).

[0034] 2 and 3 illustrate an example in which the chiral molecules 203 (303) form an organic layer 205 (305) at the boundary 204 (304), and the organic layer 205 (305) covers the inorganic chain 202 (302). The inorganic chain 202 (302) may be connected to another inorganic chain 202 (302) in the b-axis direction via the organic layer 205 (305). In addition, aromatic rings of the organic molecules bonded to the inorganic chain are stacked in the c-axis direction. The number of connected inorganic chains 202 (302) is not limited. When the organic-inorganic composite material 200 (300) is used in a circular polarization detection element or the like, the thickness of the organic-inorganic composite material 200 (300) is preferably 100 to 500 nm from the viewpoint of facilitating the flow of current in the thickness direction.

[0035] The absorption intensity per unit thickness of the organic-inorganic composite material 200 (300) is, for example, 50,000 cm －１ More than 500,000cm －１ The following are included:

[0036] In order to allow the perovskite-type material to absorb the irradiated light and to efficiently transmit the irradiated light, the surface roughness Ra (arithmetic mean roughness) of the thin film formed by each organic-inorganic composite material 200 (300) is preferably 1 nm or more and 30 nm or less. When the arithmetic mean roughness Ra of the thin film formed by the organic-inorganic composite material 200 (300) is 30 nm or less, leakage from the circular polarization detection element 220 shown in the upper diagram of FIG. 4 (lower diagram of FIG. 4) described below can be suppressed. The arithmetic mean roughness Ra can be measured using, for example, an atomic force microscope (AFM). When measuring using an atomic force microscope, the arithmetic mean roughness Ra can be obtained from an observation image obtained by using, for example, an atomic force microscope manufactured by Shimadzu Corporation, setting the scanning range and scanning mode to appropriate values ​​(specifically, for example, scanning mode: dynamic mode).

[0037] In addition, since the perovskite-type substance needs to efficiently absorb the irradiated light, the absorption intensity per unit thickness of the organic-inorganic composite material 200 (300) is, for example, 50,000 cm －１ More than 500,000cm －１ The absorption intensity per unit thickness is the value of the absorption intensity per unit thickness at the peak wavelength of the peak with the highest absorption intensity. The absorption intensity of the organic-inorganic composite material 200 (300) is measured by a transmission method.

[0038] <Circular Polarization Detection Element> The circular polarization detection element of this embodiment includes the organic-inorganic composite material described above. The circular polarization detection element is formed by stacking an anode layer, an organic-inorganic composite material, and a cathode layer in this order, and it is preferable that at least one of the anode layer and the cathode layer be optically transparent. The upper diagram in FIG. 4 is a cross-sectional view of a circular polarization detection element 220 including an organic-inorganic composite material 200. The lower diagram in FIG. 4 is a cross-sectional view of a circular polarization detection element 220 including an organic-inorganic composite material 300. The circular polarization detection element 220 is primarily a laminate formed by stacking an anode layer 206, an organic-inorganic composite material 200 (300), and a cathode layer 207 in this order. At least one of the anode layer 206 and the cathode layer 207 is optically transparent so that the perovskite-type material in the organic-inorganic composite material 200 (300) absorbs light (circularly polarized light). The negative electrode layer 206 is formed by depositing, for example, SnO ２ , TiO ２ The cathode layer 207 is bonded to the other side in the thickness direction of the organic-inorganic composite material 200 (300) via a cathode-side adhesive layer 208 (electron transport layer) made of, for example, BCP (Bathocuproine (registered trademark)), spiro-MeOTAD, TPD, or the like. When the anode layer 206 is optically transparent, the anode-side adhesive layer 208 is also optically transparent. When the cathode layer 207 is optically transparent, the cathode-side adhesive layer 209 is also optically transparent.

[0039] In the circular polarization detection element 220, the inorganic chains 202 (302) constituting the organic-inorganic composite material 200 (300) have a polycrystalline structure, so that the organic-inorganic composite material 200 (300) has high light absorption and high conductivity (carrier diffusion length, approximately 1 μm or more). Therefore, when the light irradiated onto the organic-inorganic composite material 200 (300) is circularly polarized or contains circularly polarized light, a current due to the absorbed circularly polarized light can be detected. Note that by using only R- or S-configuration chiral molecules, a chiral structure with an R- or S-configuration can be induced in the perovskite structure, selectively absorbing right-handed circularly polarized light or left-handed circularly polarized light, and the resulting current can be detected. Furthermore, even when the abundance ratio of either the R- or S-configuration is higher than the abundance ratio of the other, a chiral structure with an R- or S-configuration can be induced in the perovskite structure, selectively absorbing right-handed circularly polarized light or left-handed circularly polarized light, and the resulting current can be detected. Furthermore, by using the organic-inorganic composite material of this embodiment, it becomes possible to directly detect circularly polarized light in a longer wavelength range.

[0040] <<Method for Producing Organic-Inorganic Composite Materials>> As described above, when ion B contains only trivalent metal ions, the following two types of organic-inorganic composite materials can be produced. Organic-inorganic composite material 1: An organic-inorganic composite material in which the face-sharing oligomer structure contained in the inorganic chain is a face-sharing dimer structure consisting of two octahedral units, and the inorganic chain is composed of a chain structure formed by the face-sharing dimers orienting without sharing any vertices or faces (Figure 3). Organic-inorganic composite material 2: An organic-inorganic composite material in which the face-sharing oligomer structure contained in the inorganic chain is a face-sharing oligomer structure containing three or more octahedral units, and the inorganic chain is composed of a chain structure of face-sharing oligomers (Figure 2). Furthermore, when ion B contains a trivalent metal ion and a metal ion different from the trivalent metal ion, the following organic-inorganic composite materials can be produced. Organic-inorganic composite material 3: An organic-inorganic composite material in which the face-sharing oligomer structure contained in the inorganic chain is a face-sharing oligomer structure containing three or more units having an octahedral structure, and the inorganic chain is composed of a chain structure of face-sharing oligomers (Figure 2). Below, the manufacturing methods of organic-inorganic composite materials 1 to 3 will be explained.

[0041] <Method for producing organic-inorganic composite material 1> The method for producing organic-inorganic composite material 1 includes a first solution preparation step of dissolving an oxide or halide of ion B in a solvent while heating the solvent to obtain a first solution, a halide synthesis step of synthesizing a halide AX of a chiral molecule composed of ion A and ion X, a second solution preparation step of dissolving the halide AX in the first solution while heating the first solution to obtain a second solution, a crystal formation step of precipitating a crystal by gradually cooling the second solution, and a drying treatment of the obtained crystal to form a crystal mixture of the perovskite-type material and the chiral molecule. ３ B ２ X ９ In the method for producing the organic-inorganic composite material 1, only trivalent metal ions may be used as the ions B.

[0042] (First solution (i.e., oxide solution) preparation step) Ion B is only a trivalent metal ion. Only one type of trivalent metal ion may be used, or two or more types may be used. An oxide or halide of ion B is dissolved in a solvent while the solvent is heated. As the solvent, for example, water (hydrohalic acid) or the like can be used. The heating temperature of the solvent is preferably 80°C to 200°C, more preferably 100°C to 140°C. The heating temperature is equal to or lower than the boiling point of the solvent. Note that the oxide solution or halide solution is preferably an oxide solution or halide solution in which, in addition to a trivalent metal ion, for example, hydrogen halide (HX) such as hydrogen iodide is dissolved. An aqueous solution in which hydrogen halide (HX) is dissolved is more preferred.

[0043] (Halide Synthesis Step) A in the chiral molecule halide AX is a precursor of the chiral molecule. For example, when the halide AX is R-(+)-1-(1-naphthyl)ethylamine hydroiodide represented by the formula (1), the precursor of the chiral molecule is R-(+)-1-(1-naphthyl)ethylamine. Furthermore, when the halide AX is S-(+)-1-(1-naphthyl)ethylamine hydroiodide represented by the formula (2), the precursor of the chiral molecule is S-(+)-1-(1-naphthyl)ethylamine. The halide AX is synthesized by reacting this chiral molecule precursor with hydrogen halide. X in the chiral molecule halide AX is, for example, a fluorine ion, a chlorine ion, a bromine ion, or an iodine ion, with an iodine ion being preferred. Such a chiral molecule halide AX may be commercially available. When a commercially available product is used as the halide AX, the halide synthesis step can be omitted because it is carried out in the process of producing the commercially available product.

[0044] (Second Solution Preparation Step) In the second solution preparation step, the halide AX is dissolved in the first solution while heating the first solution to obtain a second solution. The heating temperature of the first solution is, for example, 50°C to 200°C. Preferably, it is 100°C to 150°C. More preferably, it is 110°C to 130°C. The heating temperature is below the boiling point of the solvent. The concentration of the oxide of ion B in the obtained second solution is, for example, 0.01 mol / L to 1 mol / L. Preferably, it is 0.05 mol / L to 0.5 mol / L, more preferably, it is 0.1 mol / L to 0.3 mol / L. The concentration of the halide AX in the obtained second solution is, for example, 0.02 mol / L to 2 mol / L. Preferably, it is 0.1 mol / L to 1 mol / L, more preferably, it is 0.2 mol / L to 0.6 mol / L. The molar ratio of the oxide of ion B to the halide AX in the second solution is, for example, 1:1 to 1:3, preferably 2:3 to 2:5, and more preferably 1:2. However, when substantially forming a chain structure, it is preferable to calculate the ratio so that the halide AX is blended in such that the chiral molecule ratio is 0.75 or less per molecule of ion B. In the second solution preparation step, an organic halide that can be sublimated by heating and reacts with some of the constituent elements of the perovskite-type material may be dissolved to a concentration of 1 mol / L or less, preferably 0.4 mol / L to 0.8 mol / L. The second solution is preferably an oxide solution in which hydrogen halide (HX) is dissolved. An aqueous solution in which hydrogen halide (HX) is dissolved is more preferable.

[0045] (Crystallization Step) The second solution (mixed solution) is gradually cooled to precipitate crystals of a perovskite-type substance precursor. The slow cooling may be performed at a rate of, for example, 1 to 5°C, preferably 2 to 4°C, and more preferably 3°C per hour, from the heating temperature of the first solution (e.g., 120°C) to room temperature (e.g., 30°C).

[0046] (Organic-inorganic composite material formation step) Next, the crystals made of the precursor of the perovskite type substance before the treatment are heated using a heating device to sublimate the organic halide contained in the crystals made of the precursor of the perovskite type substance before the treatment, thereby forming the compound A made of the perovskite type substance and the chiral molecule. ３ B ２ X ９ It is possible to obtain an organic-inorganic composite material having the formula (i.e., an organic-inorganic composite material composed of single-crystallized inorganic chains and chiral molecules distributed between them). Here, it is preferable that the heating temperature is 70°C to 120°C and the heating time is 15 to 60 minutes. Note that instead of the above crystal formation step and organic-inorganic composite material formation step, a spin coating method may be used in which the second solution is dropped onto a separately prepared base substrate and rotated at 1000 rpm to 5000 rpm to form a coating film composed of a precursor of a perovskite-type substance on the base substrate. The material of the base substrate is not limited.

[0047] By carrying out the crystal formation process and the organic-inorganic composite material formation process in a state where the second solution obtained in the second solution preparation process is crystallized (i.e., a state where crystals are precipitated in the second solution), the inorganic chains 302 of the organic-inorganic composite material 300 obtained through the organic-inorganic composite material formation process have a collective structure, and it is possible to effectively and efficiently obtain a single crystal that is preferentially oriented in a specific direction rather than randomly.

[0048] <Method for producing organic-inorganic composite material 3> The method for producing organic-inorganic composite material 3 includes a 1a solution preparation step of dissolving BX, a raw material for a precursor of a perovskite-type substance composed of the ion B and the ion X, in a solvent while heating the solvent to obtain a 1a solution; a halide synthesis step of synthesizing a halide AX, which is a chiral molecule composed of the ion A and the ion X; a 2a solution preparation step of dissolving the halide AX in the 1a solution while heating the 1a solution to obtain a 2a solution; a coating film formation step of applying the 2a solution onto a substrate by a spin coating method to form a coating film composed of a precursor of a perovskite-type substance on the substrate; and a heat treatment of the obtained coating film to obtain the compound ABX.３ and an organic-inorganic composite material forming step of forming an organic-inorganic composite material having the formula (I). In the method for producing the organic-inorganic composite material 3, a trivalent metal ion and a metal ion different from the trivalent metal ion are used in combination as the ion B.

[0049] (Precursor raw material BX and its synthesis process) The ions B constituting the precursor raw material BX are both trivalent metal ions and other metal ions different from the trivalent metal ions. The other metal ions different from the trivalent metal ions may be used alone or in combination of two or more. The ions X constituting the precursor raw material BX are, for example, fluorine ions, chlorine ions, bromine ions, and iodine ions, with iodine ions being preferred. The precursor raw material BX is synthesized using a synthesis method in accordance with a conventional method in the technical field, but commercially available products may also be used. When the ion B is divalent, BX ２ and when ion B is trivalent, BX ３ However, the precursor raw material BX is a general term for these. When a commercially available product is used as the raw material BX, the raw material synthesis step can be omitted because it is carried out in the process of producing the commercially available product.

[0050] (1a Solution Preparation Step) In the 1a solution preparation step, the precursor raw material BX is dissolved in a solvent while heating the solvent to obtain a 1a solution. Examples of the solvent that can be used include dimethylformamide (DMF), dimethyl sulfoxide (DMSO), γ-butyrolactone, and water (aqueous solution of hydrogen halide). The heating temperature of the solvent is, for example, 50°C to 200°C, and preferably 60°C to 100°C. The heating temperature is equal to or lower than the boiling point of the solvent. Note that the precursor raw material solution may contain hydrogen halide (HX) dissolved therein in addition to trivalent metal ions and metal ions different from the trivalent metal ions.

[0051] (Halide synthesis step) The halide synthesis step can be carried out in the same manner as in the method for producing the organic-inorganic composite material 1. A commercially available product may be used as the halide AX. When a commercially available product is used as the halide AX, the halide synthesis step can be omitted because it is carried out in the process of producing the commercially available product.

[0052] (2a Solution Preparation Step) In the 2a solution preparation step, the halide AX obtained in the halide synthesis step is dissolved in the 1a solution while heating the 1a solution to obtain a 2a solution. The heating temperature of the solvent is, for example, 50°C to 200°C, preferably 60°C to 100°C, and more preferably 70°C to 90°C. The heating temperature is below the boiling point of the solvent. The concentration of the precursor raw material BX in the obtained 2a solution is, for example, 0.05 mol / L to 10 mol / L, preferably 0.1 mol / L to 5 mol / L, and more preferably 0.2 mol / L to 2 mol / L. The concentration of the halide AX in the obtained 2a solution is, for example, 0.05 mol / L to 10 mol / L. The molar ratio of the raw material BX to the halide AX in the second solution is preferably 1:1 to 3:1, preferably 1:1 to 1:2, and more preferably 10:9 to 10:7. However, when a chain structure is to be substantially formed, it is preferable to calculate the ratio so that the halide AX is blended in such that the chiral molecule ratio is 0.75 or less per molecule of ion B. In the 2a solution preparation step, an organic halide that can be sublimated by heating and that reacts with some of the constituent elements of the perovskite-type material may be dissolved in the solution to a concentration of, for example, 1 mol / L or less, preferably 0.4 mol / L to 0.8 mol / L.

[0053] (Coating Film Forming Step) In the coating film forming step and the organic-inorganic composite material forming step, the 2a solution (mixed liquid) is dropped onto a separately prepared base substrate using a spin coating method, and the substrate is rotated at 1000 rpm to 5000 rpm to form a coating film made of a precursor of the perovskite-type substance before treatment on the base substrate. The material of the base substrate is not limited.

[0054] (Organic-inorganic composite material formation step) Next, the coating film made of the precursor of the perovskite type substance before the treatment is heated using a heating device to sublimate the organic halide contained in the coating film made of the precursor of the perovskite type substance before the treatment, thereby forming the compound ABX composed of the perovskite type substance and the chiral molecule. ３ (i.e., an organic-inorganic composite material composed of polycrystalline inorganic chains and chiral molecules distributed between them) can be obtained. Here, it is preferable that the heating temperature is 70°C to 120°C and the heating time is 15 to 60 minutes.

[0055] By carrying out the coating film formation process and the organic-inorganic composite material formation process in a state where the 2a solution obtained in the 2a solution preparation process is not crystallized (including a state where the solution is not completely crystallized), it becomes possible to effectively and efficiently obtain a polycrystalline substance in which the inorganic chains 202 of the organic-inorganic composite material 200 obtained through the organic-inorganic composite material formation process have a collective structure and are preferentially oriented in a specific direction rather than randomly.

[0056] <Method for producing organic-inorganic composite material 2> The method for producing organic-inorganic composite material 2 can be carried out in a manner similar to that for producing organic-inorganic composite material 2, except that only trivalent metal ions are used as ions B in the method for producing organic-inorganic composite material 3. Incidentally, it is preferable to use an organic solvent as the solvent for solution 2a.

[0057] In the manufacturing methods of organic-inorganic composite materials 2 and 3, a positive electrode layer 207 is formed on one side in the thickness direction of the organic-inorganic composite material 200 obtained through the organic-inorganic composite material formation step, and a negative electrode layer 206 is formed on the other side, using a film-forming method conforming to a standard method in the technical field, such as vacuum deposition or sputtering, to obtain a circular polarization detection element 220 that can output information about circularly polarized light as an electrical signal. Note that a positive electrode-side adhesive layer 209 and a negative electrode-side adhesive layer 208 may be formed between the organic-inorganic composite material 200 and the positive electrode layer 207, and between the organic-inorganic composite material 200 and the negative electrode layer 206, respectively, using a film-forming method conforming to a standard method in the technical field, such as vacuum deposition, spin coating, or sputtering.

[0058] As described above, the organic-inorganic composite material 200 (300) of this embodiment has a chain structure in which inorganic chains 202 (302) are arranged, and a chiral molecule 203 (303) having absorbance for circularly polarized light is immobilized in a one-dimensionally expanded nanospace sandwiched between adjacent inorganic chains 202 (302). The chiral molecule 203 (303) induces chirality in the arrangement of the inorganic chains 202 (302) and contains a trivalent metal ion as ion B, thereby enabling direct detection of circularly polarized light in the long wavelength range by the inorganic chains 202 (302). More specifically, each embodiment of the present invention has different characteristics as described below. The organic-inorganic composite material 1 improves the CD signal in the visible region (incidentally, the CD signal does not invert when the chiral molecule is in the R configuration or the S configuration) by imparting CD absorption derived from the face-sharing dimer structure consisting of two units. At the same time, the CD signal in the visible region is improved by imparting CD absorption derived from the pseudo-chain structure (incidentally, the CD signal is inverted when the chiral molecule is in the R configuration and when it is in the S configuration). As a result, direct detection of circularly polarized light in the long wavelength region becomes possible. The organic-inorganic composite material 3 improves the CD signal in the visible region by imparting CD absorption in the visible region. The organic-inorganic composite material 2 improves the CD signal in the visible region by imparting CD absorption over a wide range in the visible region (specifically, a wide range from 350 nm to 700 nm, preferably from 400 nm to 700 nm).

[0059] Furthermore, the inorganic chains 202 in the organic-inorganic composite materials 2 and 3 have a polycrystalline structure and are highly conductive. Therefore, by connecting electrodes to both ends in the thickness direction, when the light irradiated onto the organic-inorganic composite material 200 is circularly polarized or contains circularly polarized light, a current resulting from the circularly polarized light absorbed by the inorganic chains 202 can be detected. That is, the inorganic chains 202 formed using only R-configuration chiral molecules or S-configuration chiral molecules can selectively absorb right-handed circularly polarized light or left-handed circularly polarized light, and the resulting current can be detected. Furthermore, even when the abundance ratio of either the R-configuration or the S-configuration is higher than the abundance ratio of the other, a chiral structure with the R-configuration or the S-configuration can be induced in the perovskite structure, selectively absorbing right-handed circularly polarized light or left-handed circularly polarized light, and the resulting current can be detected.

[0060] Furthermore, the organic-inorganic composite material 200 (300) of this embodiment does not require a polarizer or a wave plate to detect circularly polarized light, and therefore has a high extinction ratio, making it possible to directly detect circularly polarized light with high sensitivity and high resolution, which was impossible to directly detect with conventional photodetectors.

[0061] Therefore, the organic-inorganic composite material 200 (300) of this embodiment can be used as a circular polarization detection element, and various devices, such as a polarization camera, incorporating the circular polarization detection element can be realized. By directly detecting circularly polarized light in the long wavelength range, it is possible to obtain information such as the intensity distribution of birefringence, which cannot be obtained with linearly polarized light.

[0062] The present invention includes a solar cell that uses the organic-inorganic composite material as the source of photovoltaic power. As described above, when the organic-inorganic composite material 200 (300) is irradiated with circularly polarized light or when the light includes circularly polarized light, a current due to the circularly polarized light absorbed by the inorganic chains 202 (302) can be detected. This phenomenon of photovoltaic power generation by the material itself (i.e., the bulk photovoltaic effect) exists, and the organic-inorganic composite material 200 (300) is expected to be a novel photovoltaic material that can efficiently utilize the visible light range. As described above, such a novel photovoltaic material generates electromotive force as a single material, and furthermore, this electromotive force does not depend on the band gap. Therefore, there is no theoretical upper limit to its photoelectric conversion efficiency. Unlike conventional solar cells that generate potential at heterointerfaces where different materials come into contact (e.g., p-n junction interfaces, light absorption layer-electron / hole transport layer interfaces), this material enables the development of solar cells that do not use such potential difference interfaces. This is expected to reduce the burden on solar cell manufacturing processes and dramatically improve their performance.

[0063] <Method for Directly Detecting Circularly Polarized Light in the Long Wavelength Range Using a Circular Polarization Detector> The method for directly detecting circularly polarized light in the long wavelength range using a circular polarization detector of this embodiment includes a step of installing the above-mentioned organic-inorganic composite material as a light-receiving layer of the circular polarization detector. That is, a plurality of organic-inorganic composite materials containing trivalent metal ions as ions B and perovskite-type substances differing in either or both of the type and composition of the trivalent metal ions (specifically, for example, a composition consisting of trivalent metal ions and other metal ions different from the trivalent metal ions) are prepared, and the plurality of organic-inorganic composite materials are interchanged as the light-receiving layer of the circular polarization detector, thereby directly detecting circularly polarized light in the long wavelength range using the circular polarization detector. A plurality of the organic-inorganic composite materials may be installed in the circular polarization detector in advance, and the organic-inorganic composite material to be used may be switched as needed.

[0064] The organic-inorganic composite material, manufacturing method, and method for directly detecting circularly polarized light in the long wavelength range according to the present disclosure have been described above. Note that the technical scope of the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention. In addition, the components in the above-described embodiments can be replaced with known components as appropriate without departing from the spirit of the present invention.

[0065] The effects of the present invention will be made clearer by the following examples. Note that the present invention is not limited to the following examples and can be practiced with appropriate modifications within the scope of the present invention.

[0066] First, we will explain the analysis and measurement methods. Various analyses and measurements were performed as follows.

[0067] [Analysis and Measurement 1] (XRD Measurement) For the organic-inorganic composite materials of Examples 1 to 3 and Comparative Example 1 described below, an X-ray diffraction (XRD) measurement was performed at room temperature using a SmartLab 9kW or MiniFlex X-ray diffraction measurement device manufactured by RIGAKU Corporation. A CuKα source was used for this measurement. The tube voltage and tube current during measurement were 40 kV and 15 mA, respectively. The measurement conditions were an ω of 1.25° and an accumulation time of 10° / min. The physical property values ​​of the chain structure according to the present invention described above were determined based on the results of the XRD measurement.

[0068] [Analysis and Measurement 2] (Circular Dichroism Spectrum Measurement) The organic-inorganic composite materials of Examples 1 to 3 and Comparative Example 1 described below were measured using a circular dichroism spectrometer (J-1500 manufactured by JASCO Corporation) to obtain the circular dichroism spectrum of each organic-inorganic composite material. In the diagram showing the circular dichroism spectrum, the horizontal axis represents the wavelength, and the vertical axis represents the CD signal intensity (CD [mdeg] = 32980 × Δ absorbance (the difference in absorption intensity between left-handed circularly polarized light and right-handed circularly polarized light)).

[0069] [Analysis and Measurement 3] (Optical Absorption Spectrum Measurement) The organic-inorganic composite materials of Examples 1 to 3 and Comparative Example 1 described below were measured using an ultraviolet-visible spectrophotometer (JASCO Corporation, J-1500) to obtain optical absorption spectra of each organic-inorganic composite material. In the diagram showing the optical absorption spectra, the horizontal axis represents wavelength and the vertical axis represents absorbance (optical absorption intensity).

[0070] Next, a method for producing the organic-inorganic composite material according to the present invention will be described. The organic-inorganic composite material was produced as follows.

[0071] Example 1 (Example of Organic-Inorganic Composite Material 1: Dimer-Type Bi Perovskite (Crystal)) The organic-inorganic composite material 1 was produced by the following procedure. 0.09 mmol of R-(+)-1-(1-naphthyl)ethylamine (R-1-NEA) or S-(-)-1-(1-naphthyl)ethylamine (S-1-NEA) was mixed with 0.2 mL of an aqueous solution (55%) of hydrogen iodide (HI), and the resulting mixture was stirred to obtain R-(+)-1-(1-naphthyl)ethylamine hydroiodide ((R-1-NEA)I) or S-(-)-1-(1-naphthyl)ethylamine hydroiodide ((S-1-NEA)I). Subsequently, bismuth oxide (Bi ２ O ３ 0.45 mmol of (R-1-NEA)I or (S-1-NEA) was mixed with 2.0 mL of an aqueous solution of hydrogen iodide (HI) (55%), and the resulting mixture was stirred to obtain an oxide solution (first solution). The resulting (R-1-NEA)I or (S-1-NEA) was dissolved in the resulting oxide solution while heating and stirring (preparation of second solution). The heating temperature was 120°C, and the stirring time was 2 hours. The resulting mixture was slowly cooled from 120°C to 30°C at a temperature drop rate of 3°C / h to precipitate crystals that serve as raw materials for the organic-inorganic composite material. The resulting crystals were dried using a dryer to obtain (R-1-NEA)I or (S-1-NEA). ３ BiI ９ Or (S-1-NEA) ３ BiI ９ The organic-inorganic composite material was obtained.

[0072] The obtained organic-inorganic composite material was subjected to XRD analysis and the like to calculate the physical properties (unit cell parameters) of the chain structure. (1) a = 8.4781(2) Å (2) b = 23.1316(5) Å (3) c = 25.0425(5) Å (4) α = β = γ = 90° (5) P2 １ 2 １ 2 １ (chiral space group)

[0073] The presence of a peak corresponding to the 011 plane (the period of the face-sharing dimer consisting of two units) at a diffraction angle (2θ) of around 5° and the improvement of the CD signal (without inversion of R and S) due to the CD absorption in the visible region imparted by the face-sharing dimer were observed, indicating that the face-sharing oligomer structure contained in the inorganic chains of the obtained organic-inorganic composite material is a face-sharing dimer structure consisting of two unit units with an octahedral structure.

[0074] 9 shows the circular dichroism spectrum (upper panel) and the optical absorption spectrum (lower panel). The solid line in the circular dichroism spectrum indicates (R-1-NEA). ３ BiI ９ and the dashed line is (S-1-NEA) ３ BiI ９ The optical absorption spectrum is (R-1-NEA) ３ BiI ９ Only (S-1-NEA) is shown. ３ BiI ９ The optical absorption spectrum of (R-1-NEA) ３ BiI ９ As shown in Figure 9, it was confirmed that the use of a trivalent metal ion as ion B enables direct detection of circularly polarized light in the long wavelength region. It was also found that the CD signal in the visible region (without inversion of R and S) can be improved by imparting CD absorptivity derived from the plane-sharing dimer (incidentally, as described above and below, the CD signal in the visible region (with inversion of R and S) can be improved by imparting CD absorptivity derived from the primary helical chain). Note that, in this regard, the results of an investigation from a structural perspective are shown in Figure 10.

[0075] Example 2 (Example of Organic-Inorganic Composite Material 3: Bi-Doped One-Dimensional Helical Pb Perovskite (Thin Film)) The thin film organic-inorganic composite material 3 was produced by the following procedure. R-(+)-1-(1-naphthyl)ethylamine (R-1-NEA) or S-(-)-1-(1-naphthyl)ethylamine (S-1-NEA) was mixed with an aqueous solution (55%) of hydrogen iodide (HI), and the resulting mixture was stirred to obtain R-(+)-1-(1-naphthyl)ethylamine hydroiodide ((R-1-NEA)I) or S-(-)-1-(1-naphthyl)ethylamine hydroiodide ((S-1-NEA)I). Subsequently, bismuth iodide (Bi ３ I) and lead iodide (PbI ２ ) and DMF were mixed, and the resulting mixture was stirred at 70°C for 10 minutes to obtain solution 1a (0.1 M Bi ３ I, 0.9M PbI ２ A DMF solution of (R-1-NEA)I or (S-1-NEA)I was obtained. The obtained (R-1-NEA)I or (S-1-NEA)I was mixed with DMF, and the resulting mixture was stirred at 70°C for 10 minutes to obtain a 0.75 M DMF solution of halide AX. The obtained DMF solution of halide AX was mixed with solution 1a while heating to obtain solution 2a. The heating conditions were 70°C, and the stirring time was 1 hour. The obtained solution 2a was used as a solution containing raw materials for the organic-inorganic composite material. The solution prepared in this manner was applied to a separately prepared base substrate, and a pre-treatment coating film was formed by spin coating (two-stage spin conditions: 1000 rpm, 10 s, followed by 5000 rpm, 60 s). The formed pre-treatment coating film was heated at 100°C for 30 minutes to obtain (R-NEA)Pb ｘ Bi ｙ I ３ (x=0.96, y=0.04, x+y=1) or (S-1-NEA)Pb ｘ Bi ｙ I ３ An organic-inorganic composite material of (x=0.96, y=0.04, x+y=1) was obtained.

[0076] The obtained organic-inorganic composite material was subjected to XRD analysis and the like to calculate the physical properties (unit cell parameters) of the chain structure. (1) a = 8.0495(2) Å (2) b = 8.3452(2) Å (3) c = 25.2398(8) Å (4) α = β = γ = 90° (5) P2 １ 2 １ 2 １ (chiral space group) From these results, it was found that the crystal lattice contracted by about 0.008 to 0.012 Å compared to that of the organic-inorganic composite material of Comparative Example 1 described later. Also, the circular dichroism spectrum (upper panel) and the optical absorption spectrum (lower panel) are shown in FIG. 6. Note that the solid lines in the circular dichroism spectrum and the optical absorption spectrum indicate the crystal lattice of (R-NEA)Pb. ｘ Bi ｙ I ３ and the dashed line is (S-1-NEA)Pb ｘ Bi ｙ I ３ As shown in Figure 6, it was confirmed that the use of trivalent metal ions as ions B enables direct detection of circularly polarized light in the long wavelength region. It was also found that the CD signal can be improved in both the visible region (400 nm region) by imparting CD absorption from Pb ions and the visible region (approximately 500 nm region) by imparting CD absorption from Bi ions.

[0077] The presence of a peak corresponding to the 002 plane (between primary helical chains) at a diffraction angle (2θ) of around 7° and the improvement of the CD signal (without inversion of R and S) due to the CD absorption in the visible region imparted by the face-sharing dimer were observed. This indicates that the face-sharing oligomer structure contained in the inorganic chains of the obtained organic-inorganic composite material is a face-sharing oligomer structure containing three or more units having an octahedral structure.

[0078] Example 3 (Example of Organic-Inorganic Composite Material 2: One-Dimensional Helical Bi Perovskite (Thin Film)) The thin film organic-inorganic composite material 2 was produced by the following procedure. R-(+)-1-(1-naphthyl)ethylamine (R-1-NEA) or S-(-)-1-(1-naphthyl)ethylamine (S-1-NEA) was mixed with an aqueous solution (55%) of hydrogen iodide (HI), and the resulting mixture was stirred to obtain R-(+)-1-(1-naphthyl)ethylamine hydroiodide ((R-1-NEA)I) or S-(-)-1-(1-naphthyl)ethylamine hydroiodide ((S-1-NEA)I). Subsequently, bismuth iodide (Bi ３ I) and DMF were mixed, and the resulting mixture was stirred at 70°C for 10 minutes to obtain solution 1a (1.0 M Bi ３ A DMF solution of (R-1-NEA)I or (S-1-NEA)I was obtained. The obtained (R-1-NEA)I or (S-1-NEA)I was mixed with DMF, and the resulting mixture was stirred at 70°C for 10 minutes to obtain a 0.75 M DMF solution of halide AX. The obtained DMF solution of halide AX was mixed with solution 1a while heating to obtain solution 2a. The heating conditions were 70°C, and the stirring time was 1 hour. The obtained solution 2a was used as a solution containing raw materials for an organic-inorganic composite material. The solution prepared in this manner was applied to a separately prepared base substrate, and a pre-treatment coating film was formed by spin coating (two-stage spin conditions: 1000 rpm, 10 s, followed by 5000 rpm, 60 s). The formed pre-treatment coating film was heated at 100°C for 30 minutes to obtain (R-1-NEA)BiI. ３ or (S-1-NEA)BiI ３ The organic-inorganic composite material was obtained.

[0079] The results of XRD analysis of the obtained organic-inorganic composite material are shown in Figure 8. The horizontal axis of Figure 8 represents the diffraction angle, and the vertical axis of Figure 8 represents the diffraction intensity. Figure 7 shows the circular dichroism spectrum (upper panel) and the optical absorption spectrum (lower panel). Note that the solid lines in the circular dichroism spectrum and the optical absorption spectrum represent (R-1-NEA)BiI ３ and the dashed line is (S-1-NEA)BiI３ As shown in Figure 7, it was confirmed that the use of trivalent metal ions as ions B enables direct detection of circularly polarized light in the long wavelength region. Furthermore, it was found that the CD signal can be improved in a wide visible region (specifically, the visible region from 400 nm to 700 nm) by providing CD absorption based on the substitution of all Pb ions with Bi ions.

[0080] Comparative Example 1 (Comparative Example for the Organic-Inorganic Composite Material of the Present Invention: Bi-Undoped One-Dimensional Helical Pb Perovskite (Thin Film)) The organic-inorganic composite material of Comparative Example 1 was produced by the following procedure. R-(+)-1-(1-naphthyl)ethylamine (R-1-NEA) or S-(-)-1-(1-naphthyl)ethylamine (S-1-NEA) was mixed with an aqueous solution (55%) of hydrogen iodide (HI), and the resulting mixture was stirred to obtain R-(+)-1-(1-naphthyl)ethylamine hydroiodide ((R-1-NEA)I) or S-(-)-1-(1-naphthyl)ethylamine hydroiodide ((S-1-NEA)I). Subsequently, lead iodide (PbI ２ ) and DMF were mixed, and the resulting mixture was stirred at 70°C for 10 minutes to obtain solution 1a (1.0 M PbI ２ A DMF solution of (R-1-NEA)I or (S-1-NEA)I was obtained. The obtained (R-1-NEA)I or (S-1-NEA)I was mixed with DMF, and the resulting mixture was stirred at 70°C for 10 minutes to obtain a 0.75 M DMF solution of halide AX. The obtained DMF solution of halide AX was mixed with solution 1a while heating to obtain solution 2a. The heating conditions were 70°C, and the stirring time was 1 hour. The obtained solution 2a was used as a solution containing raw materials for an organic-inorganic composite material. The solution prepared in this manner was applied to a separately prepared base substrate, and a pre-treatment coating film was formed by spin coating (two-stage spin conditions: 1000 rpm, 10 s, followed by 5000 rpm, 60 s). The formed pre-treatment coating film was heated at 100°C for 30 minutes to obtain (R-NEA)PbI. ３ or (S-1-NEA)PbI ３ The organic-inorganic composite material was obtained.

[0081] The obtained organic-inorganic composite material was subjected to XRD analysis and the like to calculate the physical properties (unit cell parameters) of the chain structure. (1) a = 8.0573(11) Å (2) b = 8.3568(12) Å (3) c = 25.318(4) Å (4) α = β = γ = 90° (5) P2 １ 2 １ 2 １ From these results, it was found that the crystal lattice of the organic-inorganic composite material of Example 2 was expanded by approximately 0.008 to 0.012 Å. The circular dichroism spectrum (top panel) and the optical absorption spectrum (bottom panel) are shown in FIG. 5. The solid lines in the circular dichroism spectrum and the optical absorption spectrum represent the crystal lattice of (R-NEA)PbI. ３ and the dashed line is (S-1-NEA)PbI ３ As shown in Fig. 5, it was confirmed that the CD signal in the visible region (approximately 500 nm region) was not improved by imparting CD absorbance derived from Bi ions when only divalent metal ions (Pb ions) were included as ions B and no trivalent metal ions (Bi ions) were included.

[0082] The organic-inorganic composite material of the present disclosure enables direct detection of circularly polarized light in the long wavelength region, and in particular, can further improve the CD signal in the visible region by imparting CD absorption in the visible region, and therefore has high industrial applicability.

[0083] 200, 300...organic-inorganic composite material, 201, 301...perovskite-type substance, 202, 302...inorganic chain, 203, 304...chiral molecule, 204, 304...boundary portion, 205, 305...organic layer, 206...negative electrode layer, 207...positive electrode layer, 208...negative electrode side adhesive layer, 209...positive electrode side adhesive layer, 220...circular polarization detection element

Claims

1. An organic-inorganic composite material for detecting circularly polarized light, comprising: a plurality of inorganic chains made of a perovskite-type substance and having a chain structure; and chiral molecules, wherein the chiral molecules are contained in at least a portion of the boundaries between adjacent inorganic chains; the chiral molecules are either S-type chiral molecules or R-type chiral molecules, or the abundance ratio of either is higher than the abundance ratio of the other; the crystal structure of the perovskite-type substance is oriented in a certain direction; and the perovskite-type substance and the chiral molecules are arranged in an A-type chiral structure consisting of three types of ions A, B, and X. ３ B ２ X ９ or ABX ３ wherein the ion B and the ion X form a plurality of units each having an octahedral structure, and the octahedral structures of adjacent units share one face to form a face-sharing oligomer structure, and the ion B is a trivalent metal ion.

2. The organic-inorganic composite material according to claim 1, wherein the ions B are trivalent metal ions only, the face-sharing oligomer structure is a face-sharing dimer structure consisting of two of the units, and the inorganic chain is composed of a chain structure formed by the face-sharing dimers being oriented without sharing any of a single vertex or face.

3. The organic-inorganic composite material according to claim 1, wherein the ions B comprise a trivalent metal ion and another metal ion different from the trivalent metal ion, the molar ratio of the trivalent metal ion to the other metal ion being 10:90 to 1:99, the face-sharing oligomer structure is a face-sharing oligomer structure containing three or more of the unit units, and the inorganic chain is composed of a chain structure of the face-sharing oligomer.

4. The organic-inorganic composite material according to claim 1, wherein the ions B are trivalent metal ions only, the face-sharing oligomer structure is a face-sharing oligomer structure containing three or more of the units, and the inorganic chain is composed of a chain structure of the face-sharing oligomer.

5. The organic-inorganic hybrid material according to any one of claims 1 to 4, wherein the trivalent metal ion is a bismuth ion.

6. The organic-inorganic hybrid material according to claim 3, wherein the molar ratio of the trivalent metal ions to the other metal ions is 5:95 to 1:

99.

7. The organic-inorganic hybrid material according to claim 3, wherein the other metal ions are lead ions or tin ions.

8. The organic-inorganic hybrid material according to any one of claims 1 to 4, wherein the ion A is an aromatic compound containing an ethylammonium ion.

9. The organic-inorganic hybrid material according to claim 8, wherein the aromatic compound is a polycyclic aromatic compound.

10. The organic-inorganic hybrid material according to claim 9, wherein the aromatic ring of the polycyclic aromatic compound is a naphthalene ring or an anthracene ring.

11. The organic-inorganic hybrid material according to any one of claims 1 to 4, having a surface roughness Ra of 1 nm or more and 30 nm or less.

12. A method for producing an organic-inorganic composite material according to claim 2, comprising: a first solution preparation step of dissolving an oxide or halide of ion B in a solvent while heating the solvent to obtain a first solution; a halide synthesis step of synthesizing halide AX, a chiral molecule composed of ion A and ion X; a second solution preparation step of dissolving halide AX in the first solution while heating the first solution to obtain a second solution; a crystal formation step of a precursor of a perovskite-type substance, in which crystals are precipitated while slowly cooling the second solution; and a drying treatment of the obtained crystals to obtain a chiral molecule of ion A. ３ B ２ X ９ and forming an organic-inorganic composite material having the above formula (1).

13. A method for producing an organic-inorganic composite material as defined in claim 2, comprising: a first solution preparation step of dissolving an oxide or halide of ion B in a solvent while heating the solvent to obtain a first solution; a halide synthesis step of synthesizing halide AX, a chiral molecule composed of ion A and ion X; a second solution preparation step of dissolving halide AX in the first solution while heating the first solution to obtain a second solution; and a coating film formation step of applying the second solution onto a substrate by a spin coating method to form a coating film on the substrate consisting of a precursor of a perovskite-type substance.

14. A method for producing an organic-inorganic composite material according to claim 3, comprising: a 1a solution preparation step of dissolving BX, a raw material for a precursor of a perovskite-type substance composed of the ions B and X, in a solvent while heating the solvent to obtain a 1a solution; a halide synthesis step of synthesizing a halide AX, a chiral molecule composed of the ions A and X, in the 1a solution while heating the 1a solution to obtain a 2a solution; a coating film formation step of applying the 2a solution onto a substrate by a spin coating method to form a coating film composed of a precursor of a perovskite-type substance on the substrate; and a step of heating the obtained coating film to synthesize the ABX. ３ and forming an organic-inorganic composite material having the above formula (1).

15. A method for producing an organic-inorganic composite material according to claim 4, comprising: a 1a solution preparation step of dissolving BX, a raw material for a precursor of a perovskite-type substance composed of the ions B and X, in a solvent while heating the solvent to obtain a 1a solution; a halide synthesis step of synthesizing a halide AX, a chiral molecule composed of the ions A and X, in the 1a solution while heating the 1a solution to obtain a 2a solution; a coating film formation step of applying the 2a solution onto a substrate by a spin coating method to form a coating film composed of a precursor of a perovskite-type substance on the substrate; and a step of heating the obtained coating film to synthesize the ABX. ３ and forming an organic-inorganic composite material having the above formula (1).

16. The method for producing an organic-inorganic hybrid material according to any one of claims 12 to 15, wherein the trivalent metal ion is a bismuth ion.

17. The method for producing an organic-inorganic composite material according to claim 14, wherein the other metal ions are lead ions or tin ions.

18. A circular polarization detection element comprising the organic-inorganic composite material according to any one of claims 1 to 4.

19. The circular polarization detection element according to claim 18, which is formed by laminating an anode layer, the organic-inorganic composite material, and a cathode layer in this order, and at least one of the anode layer and the cathode layer is optically transparent.

20. A device incorporating the circular polarization detection element of claim 18.

21. A device incorporating the circular polarization detection element of claim 19.

22. A method for directly detecting circularly polarized light in the long wavelength range using a circular polarization detection device, the method comprising the step of placing the organic-inorganic composite material according to any one of claims 1 to 4 as a light-receiving layer of the circular polarization detection device.

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