Chiral lead-free metal halide perovskite having spin selectivity effect

Abstract

The present invention relates to a chiral lead-free metal halide perovskite having a spin selectivity effect. The chiral lead-free metal halide perovskite according to the present invention may have a helical arrangement showing chirality that results from distortion of a structure itself in crystals due to the electrostatic interaction between a chiral organic cation (A) and a halide anion of a metal halide (BX6 octahedron, BX5 square pyramid, BX4 tetrahedron, or square planar BX4). Moreover, the chiral lead-free metal halide perovskite has a chiral-induced spin selectivity (CISS) effect, thus exhibiting spin polarization without an additional external magnetic field, and does not contain toxic Pb, and therefore can be effectively used as an environmentally friendly material in the field of spintronics applications.

Description

Spin-selective chiral lead-free metal halide perovskites

[0001] The present invention relates to a lead-free halide perovskite, and more particularly, to a chiral lead-free metal halide perovskite.

[0002] Perovskite materials exhibit a wide range of bandgaps and color controllability through the control of halogen elements, along with high photoluminescence quantum yield (PLQY) and a narrow full width at half maximum (FWHM) of ~20 nm. It is known that applying this to LCD color filters can realize high-color purity and high-color reproducibility LCDs.

[0003] However, high-performance perovskites contain lead (Pb) as a metal cation. In the European Union, the use of hazardous heavy metals, including lead, in electronic devices is regulated by the Restriction of Hazardous Substances Directive (RoHS), and other countries are expected to gradually adopt similar regulations.

[0004] The first object of the present invention is to provide a chiral lead-free metal halide perovskite having spin selectivity.

[0005] A second object of the present invention is to provide a method for producing a chiral lead-free metal halide perovskite having the spin selectivity.

[0006] In order to solve the above problem, one aspect of the present invention provides a chiral lead-free metal halide perovskite having spin selectivity. The chiral lead-free metal halide perovskite having spin selectivity is ABX3, A'2A. n-1 BX 3n+1 , ABX4, A2BX 4, A2BX5, A3BX5, A4B2X 10, ABX5, A3B2X9, AB2X 10 Or a perovskite having the chemical formula A2B1B'X6, wherein A is a chiral organic cation or a combination of different chiral organic cations, A' is a chiral organic cation different from A or an achiral organic cation, B and B' are metal ions other than Pb, organic cations, inorganic cations, ammonium ions or a combination thereof, and X is F - , Cl - , Br - , I - Or a combination thereof, n is an integer from 1 to 10, and the perovskite is characterized in that BX6 octahedron, BX5 square pyramid, BX4 tetrahedron or BX4 planar square unit layers and A unit layers bonded to X by electrostatic attraction are alternately arranged, and the chirality of A is transferred to the BX6 octahedron, BX5 square pyramid, BX4 tetrahedron or BX4 planar square unit layers by the electrostatic attraction, thereby having chirality-induced spin polarization current selectivity.

[0007] The above chiral organic cation may be a cation represented by the following chemical formula A or chemical formula B.

[0008] [Chemical Formula A]

[0009]

[0010]

[0011] [Chemical Formula B]

[0012]

[0013] (In the above chemical formulas A and B, R a and R b are independently substituted or unsubstituted C1~C 10 Alkyl, C3~C 10 Cycloalkyl, C3~C 10 Heterocycloalkyl, C6~C 12 Aryl, C6~C 12 Heteroaryl or C6~C 12 Heteroaryl-C1~C10 Alkyl, and the heterocycloalkyl or heteroaryl contains N, O, S, P or Se in the ring, and the R a Wow R b is different, and the above R a Wow R b can be combined with each other to form a ring, and R c is NH3 + , RNH3 + , (CH2) n NH3 + , COOH, (CH2) n COOH, OH or CH3, and the above R c COOH, (CH2) n If COOH, OH or CH3, R a is RNH3 + , (CH2) n NH3 + or NH3 + is substituted with, where R is a substituted or unsubstituted C1~C 10 Alkyl, C3~C 10 Cycloalkyl, C3~C 10 Heterocycloalkyl, C6~C 12 Aryl, C6~C 12 Heteroaryl or C6~C 12 Heteroaryl-C1~C 10 is alkyl, and the heterocycloalkyl or heteroaryl contains N, O, S, P or Se in the ring, n is an integer from 1 to 10, and * is a chiral central carbon.)

[0014] The above R a and R b In , the cycloalkyl, heterocycloalkyl, aryl or heteroaryl may be substituted with halogen, C1~C2 alkyl or C1~C2 alkoxy.

[0015] The above chiral organic cation may be a cation represented by the following chemical formula A-1 or chemical formula B-1.

[0016] [Chemical Formula A-1]

[0017]

[0018] [Chemical Formula B-1]

[0019]

[0020] (In the above chemical formulas A-1 and B-1, the R a , R b and * are as defined in the above chemical formulas A and B.)

[0021] The above chiral organic cation may be selected from the following group.

[0022]

[0023]

[0024]

[0025]

[0026] The above chiral organic cation may be a cation represented by the following chemical formula A-2 or chemical formula B-2.

[0027] [Chemical Formula A-2]

[0028]

[0029] [Chemical Formula B-2]

[0030]

[0031] (In the above chemical formulas A-2 and B-2, R c is NH3 + , RNH3 + , (CH2) n NH3 + , COOH, (CH2) n COOH, OH or CH3, and R d C5~C which does not have a plane of symmetry based on the chiral center carbon 12 Cycloalkyl or C5~C 12Heterocycloalkyl, wherein said heterocycloalkyl contains N, O, S, P or Se in the ring, and said cycloalkyl or said heterocycloalkyl is C6~C 12 It can be fused with aryl, and the above R c COOH, (CH2) n If COOH, OH or CH3, the above R d NH within the ring + or NH2 + RNH3 as a substituent substituted with or bonded to the ring + , (CH2) n NH3 + or NH3 + having a substituent, where R is a substituted or unsubstituted C1~C 10 Alkyl, C3~C 10 Cycloalkyl, C3~C 10 Heterocycloalkyl, C6~C 12 Aryl, C6~C 12 Heteroaryl or C6~C 12 Heteroaryl-C1~C 10 is alkyl, and the heterocycloalkyl or heteroaryl contains N, O, S, P or Se in the ring, n is an integer from 1 to 10, and * is a chiral central carbon.)

[0032] The above chiral organic cation may be selected from the following group.

[0033]

[0034] The above achiral organic cation is R e NH3 + and R e It can be C1~C6 alkyl or C1~C6 haloalkyl.

[0035] The above B and B' may be independently selected from the group consisting of Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, La, Ce, Pr, Nd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os, Ir, Pt, Th, Pa, U, Pu, Am, Si, Zn, Ga, As, Se, Ag, Cd, In, Sn, Sb, Te, Au, Hg, Tl and Bi, and may be selected from the group consisting of cations of elements, organic cations, inorganic cations and ammonium ions.

[0036] The above B and B' can independently have an octahedron, a tetrahedra, a square plane structure, or a square pyramid structure.

[0037] The above chiral lead-free metal halide perovskite can have a spiral structure in the crystal by twisting and combining the BX6 octahedral, BX5 square pyramidal, BX4 tetrahedral or BX4 planar square unit layers and the A unit layers bonded to X by electrostatic attraction.

[0038] The above chiral lead-free metal halide perovskite can control the degree of twist of the helical structure within the crystal of the perovskite by controlling the composition of X.

[0039] The chiral lead-free metal halide perovskite having the above magnetic properties may have a crystal size of 1 nm to 500 cm.

[0040] The above-described chiral lead-free metal halide perovskite having magnetism may have a three-dimensional (3D), two-dimensional (2D), one-dimensional (1D), or zero-dimensional (0D) structure.

[0041] The chiral lead-free metal halide perovskite having the above magnetism can exhibit circular dichroism in the range of 200 nm to 1000 nm.

[0042] The above chiral lead-free metal halide perovskites are C1, P1, C2, P121, P1211, C121, D2, P222, P2221, P21212, P212121, C2221, C222, F222, I222, I212121, C4, P4 , P41, P42, P43, I4, I41, D4, P422, P4212, P4122, P41212, P4222, P42212, P4322, P43212, I422, I4122, C3, P3, P31, P32, R3, D3, P312, P321, P3112, P3121, P3212, P32 21,R32,C6,P6,P61,P65,P62,P64,P63,D6,P622,P6122,P6522,P6222,P6422,P6322,T,P23,F23,I23,P213,I213,O,P432,P4232,F432,F4132,I432,P4332,P4132 or I4132 can have a point group or space group.

[0043] The above chiral lead-free metal halide perovskite can be crystallized through a solvent evaporation method, an antisolvent vapor-assisted method, an inverse temperature crystallization method, a bridgman method, a hydrothermal method, a mechanochemical reaction method, a solvent-mediated method, or a space-confined method.

[0044] In addition, another aspect of the present invention provides a device comprising the chiral lead-free metal halide perovskite.

[0045] The above device may be a spin light emitting diode, a photosensor device, a solar cell, a memory device, or a water electrolytic cell.

[0046] In addition, another aspect of the present invention provides a lead-free metal halide perovskite crystal. The lead-free metal halide perovskite crystal is a perovskite crystal in which BX6 octahedral, BX5 square pyramidal, BX4 tetrahedral or BX4 planar square unit layers and A unit layers bonded to X by electrostatic attraction are alternately arranged, wherein A is a chiral organic cation, B is a metal ion other than Pb, and X is F - , Cl - , Br - , I - Or a combination thereof, and the chirality of A is characterized in that it is transferred to a BX6 octahedron, BX5 square pyramid, BX4 tetrahedron or BX4 planar square unit layer by the electrostatic attraction, and the spin direction of the conduction electrons is determined by an internal magnetic field formed by the mutual influence between the conduction electrons and the chiral crystal under an electric field, thereby having spin polarization current selectivity without an external magnetic field.

[0047] The lead-free chiral metal halide perovskite according to the present invention can have a helical structure in which the structure within the crystal itself is distorted due to the electrostatic interaction between the chiral organic cation (A) and the halide anion of the metal halide (BX6 octahedron, BX5 square pyramid, BX4 tetrahedron or BX4 planar square) and exhibits chirality. Furthermore, since it has a chiral-induced spin-selectivity effect (CISS effect), it exhibits spin polarization even without an additional external magnetic field, and since it does not contain toxic Pb, it can be usefully used in spintronics applications as an environmentally friendly material.

[0048] Figure 1 shows the chemical structure of a chiral material.

[0049] Figure 2 is a diagram showing two directions of circular polarization.

[0050] Figure 3 is a diagram showing the difference in absorption according to the circular polarization direction of a chiral material.

[0051] Figure 4 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) are pictures of the decisions.

[0052] Figure 5 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) crystals, showing the crystal structure of palladium halide.

[0053] FIG. 6 shows (a) the crystal structure of a metal halide within the crystal and (b) the helical arrangement when combined with a chiral organic substance in a (R-MBA)2PdBr4 crystal according to one embodiment of the present invention.

[0054] FIG. 7 shows the distance between the hydrogen of the halide and the chiral organic substance in the crystal in a (R-MBA)2PdBr4 crystal according to one embodiment of the present invention.

[0055] FIG. 8 shows the coordination environment between a metal halide and a chiral organic compound in a (R-MBA)2PdBr4 crystal according to one embodiment of the present invention.

[0056] Figure 9 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 0.75 Cl 0.25 ) In the 4-crystal, the crystal structure of the metal halide within the crystal shows (a) the angle, (b) the distance, and (c) the helical arrangement when combined with a chiral organic substance.

[0057] Figure 10 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 0.75 Cl 0.25)4 In the crystal, it represents the coordination environment between the metal halide and the chiral organic compound within the crystal.

[0058] Figure 11 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 0.5 Cl 0.5 ) In the 4-crystal, the crystal structure of the metal halide within the crystal shows (a) the angle, (b) the distance, and (c) the helical arrangement when combined with a chiral organic substance.

[0059] Figure 12 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 0.5 Cl 0.5 )4 In the decision, it indicates the distance between the hydrogen of the halide and chiral organic substance in the crystal.

[0060] Figure 13 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 0.5 Cl 0.5 )4 In the crystal, it represents the coordination environment between the metal halide and the chiral organic compound within the crystal.

[0061] Figure 14 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 0.25 Cl 0.75 )4 In the decision, it indicates the angle and distance of the crystal structure of the metal halide within the crystal.

[0062] Figure 15 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 0.25 Cl 0.75 )4 In the crystal, it represents the coordination environment between the metal halide and the chiral organic compound within the crystal.

[0063] FIG. 16 shows the angles and distances of the crystal structure of metal halides within a (R-MBA)2PdCl4 crystal according to one embodiment of the present invention.

[0064] Figure 17 shows the distance between the hydrogen of the halide and the chiral organic substance in the crystal in the (R-MBA)2PdCl4 crystal according to one embodiment of the present invention.

[0065] Figure 18 shows the coordination environment between a metal halide and a chiral organic compound in a (R-MBA)2PdCl4 crystal according to one embodiment of the present invention.

[0066] FIG. 19 is a simulation of (R-MBA)2PdBr4 crystals, powder, and XRD data of films according to one embodiment of the present invention.

[0067] Figure 20 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 0.75 Cl 0.25 )4 Simulation of crystals, XRD data of powder and film.

[0068] Figure 21 is a diagram showing a (R-MBA)2Pd(Br) according to one embodiment of the present invention. 0.5 Cl 0.5 )4 Simulation of crystals, XRD data of powder and film.

[0069] Figure 22 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 0.25 Cl 0.75 )4 Simulation of crystals, XRD data of powder and film.

[0070] Figure 23 is a simulation of (R-MBA)2PdCl4 crystals, powder, and XRD data of films according to one embodiment of the present invention.

[0071] FIG. 24 shows the degree of excellent intralattice distortion in the crystal of (R-MBA)2PdBr4 according to one embodiment of the present invention.

[0072] Figure 25 is a diagram showing (R- / S-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) is a graph showing the anisotropy factor representing the optical chiral properties of films containing the crystals.

[0073] Figure 26 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x)4(x = 0, 0.25, 0.5, 0.75 and 1) crystals, (a) ultraviolet-visible (UV-Vis) spectrophotometric measurement data of films containing (R- / S-MBA)2Pd(Br) according to an embodiment of the present invention, and (b) 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) is a graph showing the circular dichroism characteristics of films containing the crystals.

[0074] Figure 27 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) crystals, indicating the crystal lattice orientation of the film.

[0075] Figure 28 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) shows the variation of the interlayer spacing within the crystals of the film.

[0076] Figure 29 shows the chirality-induced spin selectivity of a (R- / S-MBA)2PdBr4 film according to one embodiment of the present invention.

[0077] Figure 30 is (R-MBA)4Bi2I according to one embodiment of the present invention. 10 , (R-MBA)4Bi2Br 10 and (R-MBA)4Bi2Cl 10 These are pictures of decisions.

[0078] Figure 31 is (S-MBA)4Bi2I according to one embodiment of the present invention. 10 and (R-MBA)4Bi2Br 10 It shows the crystal structure.

[0079] Figure 32 is (R- / S-MBA)4Bi2I according to one embodiment of the present invention. 10 (a) Graph showing the circular dichroism characteristics of the crystals and (b) ultraviolet-visible (UV-Vis) spectrophotometric measurement data.

[0080] Figure 33 is (R- / S-MBA)4Bi2Br according to one embodiment of the present invention. 10 (a) Graph showing the circular dichroism characteristics of the crystals and (b) ultraviolet-visible (UV-Vis) spectrophotometric measurement data.

[0081] Figure 34 is (R- / S-MBA)4Bi2Cl according to one embodiment of the present invention. 10 (a) Graph showing the circular dichroism characteristics of the crystals and (b) ultraviolet-visible (UV-Vis) spectrophotometric measurement data.

[0082] Hereinafter, an embodiment of the present invention will be described in detail with reference to the attached drawings.

[0083] While the present invention is susceptible to numerous modifications and variations, specific embodiments thereof are illustrated in the drawings and will be described in detail below. However, the invention is not intended to be limited to the particular forms disclosed; rather, the invention includes all modifications, equivalents, and alternatives consistent with the spirit of the invention as defined by the claims.

[0084] When an element such as a layer, region or substrate is referred to as existing "on" another element, it will be understood that this may be directly on the other element, or that there may be intermediate elements in between.

[0085] Although the terms first, second, etc. may be used to describe various elements, components, regions, layers and / or regions, it will be understood that these elements, components, regions, layers and / or regions should not be limited by these terms.

[0086]

[0087] [Chiral lead-free metal halide perovskites with spin selectivity]

[0088] One aspect of the present invention provides a chiral lead-free metal halide perovskite having spin selectivity.

[0089] The chiral lead-free metal halide perovskite having the above spin selectivity may include single-crystal, polycrystalline or colloidal nanocrystal particles, and thus, perovskite and perovskite crystal may be used interchangeably in the present specification.

[0090] Chiral lead-free metal halide perovskites with the above spin selectivity are ABX3, A'2A n-1 BX 3n+1 , ABX4, A2BX 4, A2BX5, A3BX5, A4B2X 10 , ABX5, A3B2X9, AB2X 10 Or a perovskite having the chemical formula A2B1B'X6, wherein A is a chiral organic cation or a combination of different chiral organic cations, A' is a chiral organic cation different from A or an achiral organic cation, B and B' are metal ions other than Pb, organic cations, inorganic cations, ammonium ions or a combination thereof, and X is F - , Cl - , Br - , I - Or a combination thereof, n is an integer from 1 to 10, and the perovskite is characterized in that BX6 octahedron, BX5 square pyramid, BX4 tetrahedron or BX4 planar square unit layers and A unit layers bonded to X by electrostatic attraction are alternately arranged, and the chirality of A is transferred to the BX6 octahedron, BX5 square pyramid, BX4 tetrahedron or BX4 planar square unit layers by the electrostatic attraction.

[0091] The above chiral perovskite crystal is characterized by having induced spin polarization current selectivity without an external magnetic field, in that when a current moves through the thin film under an electric field after forming the thin film, a magnetic field is generated internally by the mutual influence between the conduction electrons constituting the current and the chiral crystal, and the energy according to the spin direction of the conduction electrons changes due to the internal magnetic field, so that only electrons having a relatively stable spin direction pass through the chiral perovskite crystal.

[0092] The crystal structure of the above perovskite includes a face-centered cubic (FCC) structure with a central metal ion (B) in the center, six halide ions (X) located on all surfaces of the hexahedron, and a body-centered cubic (BCC) structure with eight As located on all vertices of the hexahedron, wherein A is characterized in that it is a chiral substance, particularly a chiral organic cation.

[0093] Figure 1 shows the chemical structure of a chiral material.

[0094] Referring to Figure 1, the chiral material refers to an isomer material that has the same molecular weight and components that make up the material, but cannot be superimposed on each other because the arrangement is mirror-image symmetric.

[0095] The above chiral substances are divided into R-form and S-form, and these chiral substances can appear in organic substances having a molecular structure.

[0096] Specifically, in the chiral lead-free metal halide perovskite having the spin selectivity, A and A' may be chiral organic cations. The chiral organic cation enters the perovskite lattice and binds to X of the metal halide (BX6 octahedron, BX5 square pyramid, BX4 tetrahedron or BX4 planar square) unit layer by electrostatic attraction, and at this time, the distortion is transmitted by the distorted electrostatic attraction between the chiral organic cation and the halide anion, so that the octahedron, square pyramid, tetrahedron or planar square of the metal halide is distorted, and the bond angle, bond distance, etc. change asymmetrically. Therefore, the perovskite having the chiral organic cation may have chiral characteristics like the chiral organic cation.

[0097] More specifically, A is a chiral organic cation or a combination of different chiral organic cations, and A' may be a chiral organic cation different from A or may be an achiral organic cation.

[0098] The above chiral organic cation may be a cation represented by the following chemical formula A or chemical formula B.

[0099] [Chemical Formula A]

[0100]

[0101] [Chemical Formula B]

[0102]

[0103] (In the above chemical formulas A and B,

[0104] R a and R b are independently substituted or unsubstituted C1~C 10 Alkyl, C3~C 10 Cycloalkyl, C3~C 10 Heterocycloalkyl, C6~C 12 Aryl, C6~C 12 Heteroaryl or C6~C 12 Heteroaryl-C1~C 10is alkyl, and the heterocycloalkyl or heteroaryl contains N, O, S, P or Se in the ring,

[0105] The above R a Wow R b are different,

[0106] The above R a Wow R b can be combined with each other to form a ring, and R c is NH3 + , RNH3 + , (CH2) n NH3 + , COOH, (CH2) n COOH, OH or CH3,

[0107] The above R c COOH, (CH2) n If COOH, OH or CH3, R a is RNH3 + , (CH2) n NH3 + or NH3 + is replaced by,

[0108] Here, R is substituted or unsubstituted C1~C 10 Alkyl, C3~C 10 Cycloalkyl, C3~C 10 Heterocycloalkyl, C6~C 12 Aryl, C6~C 12 Heteroaryl or C6~C 12 Heteroaryl-C1~C 10 is alkyl, and the heterocycloalkyl or heteroaryl contains N, O, S, P or Se in the ring, and n is an integer from 1 to 10,

[0109] * is a chiral central carbon.)

[0110] The above R a and R b In , the cycloalkyl, heterocycloalkyl, aryl or heteroaryl may be substituted with halogen, C1~C2 alkyl or C1~C2 alkoxy.

[0111] As an example, the chiral organic cation may be a cation represented by the following chemical formula A-1 or chemical formula B-1.

[0112] [Chemical Formula A-1]

[0113]

[0114] [Chemical Formula B-1]

[0115]

[0116] (In the above chemical formulas A-1 and B-1,

[0117] The above R a , R b and * are as defined in the above chemical formulas A and B.)

[0118] The above chiral organic cation may be at least one selected from the following group or a combination thereof.

[0119]

[0120]

[0121]

[0122] Additionally, as an example, the chiral organic cation may be a cation represented by the following chemical formula A-2 or chemical formula B-2.

[0123] [Chemical Formula A-2]

[0124]

[0125] [Chemical Formula B-2]

[0126]

[0127] (In the above chemical formulas A-2 and B-2,

[0128] R c is NH3 + , RNH3 + , (CH2) n NH3 + , COOH, (CH2) nCOOH, OH or CH3,

[0129] R d C5~C which does not have a plane of symmetry based on the chiral center carbon 12 Cycloalkyl or C5~C 12 is heterocycloalkyl, wherein said heterocycloalkyl contains N, O, S, P or Se in the ring,

[0130] The above cycloalkyl or the above heterocycloalkyl is C6~C 12 It can be fused with aryl,

[0131] The above R c COOH, (CH2) n If COOH, OH or CH3, the above R d NH within the ring + or NH2 + RNH3 as a substituent substituted with or bonded to the ring + , (CH2) n NH3 + or NH3 + has a substituent,

[0132] Here, R is substituted or unsubstituted C1~C 10 Alkyl, C3~C 10 Cycloalkyl, C3~C 10 Heterocycloalkyl, C6~C 12 Aryl, C6~C 12 Heteroaryl or C6~C 12 Heteroaryl-C1~C 10 is alkyl, and the heterocycloalkyl or heteroaryl contains N, O, S, P or Se in the ring, and n is an integer from 1 to 10,

[0133] * is a chiral central carbon.)

[0134] The above chiral organic cation may be at least one selected from the following group or a combination thereof.

[0135]

[0136] The above achiral organic cation is Re NH3 + and R e may be C1~C6 alkyl or C1~C6 haloalkyl.

[0137] In the above chiral lead-free metal halide perovskite, B and B' may be independently selected from the group consisting of Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, La, Ce, Pr, Nd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os, Ir, Pt, Th, Pa, U, Pu, Am, Si, Zn, Ga, As, Se, Ag, Cd, In, Sn, Sb, Te, Au, Hg, Tl and Bi, and may be selected from the group consisting of cations of elements, organic cations, inorganic cations and ammonium ions.

[0138] The above B and B' may independently have an octahedron, a tetrahedron, a square plane structure, or a square pyramid structure, and may have a structure in which metal is coordinated to the square pyramid structure (square pyramid metal coordination geometry).

[0139] The above chiral lead-free metal halide perovskite can have an arrangement of a spiral structure within the crystal by twisting and combining a BX6 octahedron, BX5 square pyramid, BX4 tetrahedron or BX4 planar square unit layer and an A unit layer bonded to X by electrostatic attraction, and when the B or B' has an octahedron, tetrahedron, planar square structure or square pyramid structure, it becomes easy to form an asymmetrically twisted structure by combining with A, which is a chiral organic cation, so that it can effectively have an arrangement of a spiral structure having chirality.

[0140] The above X is a halide ion, specifically F - , Cl - , Br - , I - Or it can be a combination of these. At this time, the degree of distortion within the crystal of the perovskite can be controlled by controlling the composition of X. Specifically, as shown in Fig. 25, the interaction between the chiral organic material and the metal halide structure appears differently depending on the halide composition of the manufactured chiral non-lead metal halide perovskite, and this appears as a change in the distortion of the crystal structure. Therefore, the degree of distortion within the crystal can be controlled by controlling the composition of the halide, i.e., X.

[0141]

[0142] In the above chiral metal halide perovskite, a part of A may be substituted with another A, a part of B may be substituted with another B, or a part of X may be substituted with another X. That is, the A may be A a (1-α) A b α And, the above B is B a (1-β) B b β and the above X is X a (1-γ) X b γ And, at this time, the above A a Wow A b are included in the scope of A but are different from each other, and B a Wow B b are included in the range of B but are different, and X a Wow X b are included in the range of X, but may be different.

[0143] When a part of the above A is replaced with another A, a part of the above B is replaced with another B, or a part of the above X is replaced with another X, the replacement ratio may be from 0.1 mol% to 99.9 mol%. That is, 0.1≤α≤99.9, 0.1≤β≤99.9, and 0.1≤γ≤99.9.

[0144]

[0145] The above chiral lead-free metal halide perovskite may have a crystal size of 1 nm to 500 cm.

[0146] Additionally, the perovskite crystal may have a spherical, cylindrical, elliptical, or polygonal prism shape.

[0147] The above chiral lead-free metal halide perovskite may have a three-dimensional (3D), two-dimensional (2D), one-dimensional (1D), or zero-dimensional (0D) structure.

[0148] The above chiral lead-free metal halide perovskites are C1, P1, C2, P121, P1211, C121, D2, P222, P2221, P21212, P212121, C2221, C222, F222, I222, I212121, C4, P4 , P41, P42, P43, I4, I41, D4, P422, P4212, P4122, P41212, P4222, P42212, P4322, P43212, I422, I4122, C3, P3, P31, P32, R3, D3, P312, P321, P3112, P3121, P3212, P32 21,R32,C6,P6,P61,P65,P62,P64,P63,D6,P622,P6122,P6522,P6222,P6422,P6322,T,P23,F23,I23,P213,I213,O,P432,P4232,F432,F4132,I432,P4332,P4132 or I4132 can have a point group or space group.

[0149] Additionally, the chiral lead-free metal halide perovskite can exhibit circular dichroism in the range of 200 nm to 1000 nm.

[0150] Figure 2 shows two directions of circular polarization, and Figure 3 shows the difference in absorption according to the direction of circular polarization of a chiral material.

[0151] Referring to Figure 2, there are left-hand circular polarization (LCP) and right-hand circular polarization (RCP) in circular polarization, and chiral materials have the characteristic of being able to selectively absorb only one direction of circular polarization among these directions.

[0152] Therefore, as shown in Fig. 3, when two types of circularly polarized light are irradiated on a chiral material, it absorbs a lot of one direction, and this chiral characteristic can be confirmed through circular dichroism (CD).

[0153] FIG. 26 and FIG. 32-34 are graphs showing circular dichroism characteristics of chiral metal halide perovskites according to an embodiment of the present invention. Referring to FIG. 26 and FIG. 32-34, the chiral lead-free metal halide perovskite according to the present invention contains R- / S-chiral organic cations in the lattice, so that the chiral organic cations selectively absorb circularly polarized light at a wavelength of 300 nm or less, for example, at a wavelength of 200 nm to 300 nm, and when a chiral transition occurs from the chiral organic cation to the halide anion of the metal halide octahedron, a signal is emitted at a wavelength band (300 nm to 1000 nm) absorbed by the metal halide octahedron, thereby shifting the wavelength band of circular dichroism. Through this circular dichroism, it can be seen that the chiral metal halide perovskite of the present invention exhibits chiral properties, and through the shift of the wavelength of the circular dichroism, it has the property of transferring the chiral properties of the chiral organic cation to the metal halide structure.

[0154]

[0155] Figures 6, 9, 11, 14, and 16 illustrate a twisted structure of a chiral lead-free metal halide perovskite according to an embodiment of the present invention. As such, the chiral metal halide perovskite according to the present invention has a twisted structure within the crystal itself due to the electrostatic interaction between the chiral organic cation (A) and the halide anion of the metal halide (BX5 square pyramid), and may also have a helical structure arrangement exhibiting chirality, as shown in Figures 6, 9, and 11.

[0156]

[0157] In addition, the chiral lead-free metal halide perovskite according to the present invention exhibits spin selectivity by chiral transition.

[0158] Figure 29 shows the chirality-induced spin selectivity of a (R- / S-MBA)2PdBr4 film according to one embodiment of the present invention.

[0159] Referring to Fig. 29, in a chiral lead-free metal halide perovskite in which a chiral transition has occurred, electron spins passing through it are selectively filtered as the metal halide (BX5 square pyramid) is twisted. Therefore, when the spin direction of a Co-Cr coated tip is fixed to up spin or down spin and the measured current value is read, a difference occurs similar to a chiral organic material, and from this, chirality-induced spin selectivity can be confirmed.

[0160] Therefore, the chiral lead-free metal halide perovskite according to the present invention has a chiral-induced spin-selectivity effect (CISS effect), and thus exhibits spin polarization without an additional external magnetic field, and thus can be usefully used in spintronics applications, such as spin-light-emitting diodes, memory devices, optical sensors, solar cells, and water electrolysis.

[0161]

[0162] The above perovskite crystal can be dissolved or dispersed in an organic solvent, and the organic solvent can be a protic solvent or an aprotic solvent. For example, the protic solvent can be selected from methanol, ethanol, isopropyl alcohol, tert-butanol, and formic acid, and the aprotic solvent can be selected from dimethylformamide, dimethylsulfoxide, xylene, toluene, hexane, cyclohexene, gamma butyrolactone, N-methylpyrrolidone, and dichloroethylene, trichloroethylene, chloroform, chlorobenzene, and dichlorobenzene.

[0163]

[0164] Meanwhile, the perovskite crystal may be a nanocrystal particle further including a plurality of organic ligands (not shown) surrounding the surface.

[0165] The above organic ligand may include an alkyl halide or an organic acid.

[0166] The above alkyl halide may have a structure of alkyl-X. The halogen element corresponding to X at this time may include Cl, Br or I, etc. In addition, the alkyl structure at this time may include C n H 2n+1 Acyclic alkyl having the structure of C n H 2n+1 Primary alcohol, secondary alcohol, tertiary alcohol with structures such as OH, alkylamine with structures of alkyl-N (ex. Hexadecyl amine, 9-Octadecenylamine 1-Amino-9-octadecene(C 19 H 37N), p-substituted aniline, phenyl ammonium or fluorine ammonium.

[0167] The organic acids are 4,4'-Azobis(4-cyanovaleric acid), Acetic acid, 5-Aminosalicylic acid, Acrylic acid, L-Aspentic acid, 6-Bromohexanoic acid, Bromoacetic acid, Dichloro acetic acid, Ethylenediaminetetraacetic acid, Isobutyric acid, Itaconic acid, Maleic acid, r-Maleimidobutylic acid. It may contain r-Maleimidobutyric acid, L-Malic acid, 4-Nitrobenzoic acid, 1-Pyrenecarboxylic acid or oleic acid.

[0168]

[0169] The chiral lead-free metal halide perovskite having the spin selectivity can be crystallized through a solvent evaporation method, an antisolvent vapor-assisted method, an inverse temperature crystallization method, a bridgman method, a hydrothermal method, a mechanochemical reaction method, a solvent-mediated method, or a space-confined method.

[0170] As an example, the chiral lead-free metal halide perovskite having the spin selectivity can be prepared by a solvent evaporation method, and a method for preparing a chiral lead-free metal halide perovskite using the solvent evaporation method is described below.

[0171] The method for producing chiral lead-free metal halide perovskite through the above solvent evaporation method is

[0172] A step of preparing a perovskite precursor solution by mixing a first solution containing a metal halide and a second solution containing a chiral organic material; and

[0173]

[0174] It includes a step of evaporating the perovskite precursor solution to remove the solvent, and then cooling it to precipitate a crystal.

[0175]

[0176] Hereinafter, a method for producing a chiral lead-free metal halide perovskite having spin selectivity according to the present invention is described in detail step by step.

[0177] First, prepare a perovskite precursor solution.

[0178] The above perovskite precursor solution can be prepared by mixing a first solution containing a metal halide and a second solution containing a chiral organic substance, which is a material for a chiral organic cation, dissolved therein.

[0179] The above first solution can be formed by dissolving a metal halide in an acid solvent at a certain ratio.

[0180] The above second solution can be formed by dissolving a chiral organic substance in an acid solvent at a certain ratio, and at this time, the acid solvent may be a halide hydroacid, but is not limited thereto.

[0181] The mixing of the first solution and the second solution can be performed by first heating the first solution and then slowly adding the second solution to dissolve it.

[0182]

[0183] Next, the prepared perovskite precursor solution can be heated to evaporate the solvent and cooled to precipitate crystals.

[0184] The precipitated crystals can be further washed with an antisolvent to remove impurities and then dried in a vacuum.

[0185] At this time, it is preferable to use a solvent that does not dissolve the perovskite structure as the antisolvent, and chloroform, chlorobenzene, dichlorobenzene, toluene, xylene, acetone, cyclohexane, benzene, methanol, ethanol, ethylene glycol, 2-propanol, tetrahydrofuran, acetonitrile, benzonitrile or a combination thereof can be used as such an antisolvent.

[0186]

[0187] The lead-free chiral metal halide perovskite according to the present invention can have a helical structure in which the structure within the crystal itself is distorted due to the electrostatic interaction between the chiral organic cation (A) and the halide anion of the metal halide (BX6 octahedron, BX5 square pyramid, BX4 tetrahedron or BX4 planar square) and exhibits chirality. Furthermore, since it has a chiral-induced spin-selectivity effect (CISS effect), it exhibits spin polarization even without an additional external magnetic field, and since it does not contain toxic Pb, it can be usefully used in spintronics applications as an environmentally friendly material.

[0188] Hereinafter, preferred manufacturing examples and experimental examples are presented to aid in understanding the present invention. However, the following manufacturing examples and experimental examples are provided solely to aid in understanding the present invention, and the present invention is not limited to the following manufacturing examples and experimental examples.

[0189]

[0190] Manufacturing Example 1-5: Preparation of chiral lead-free metal halide perovskite crystals

[0191] [Manufacturing Example 1: Preparation of (R- / S-MBA)2PdBr4 crystals]

[0192] (R- / S-MBA)2PdBr4 crystals were synthesized by the solvent evaporation method.

[0193] Specifically, a first solution was prepared by dissolving a metal halide in an acid solvent. At this time, hydrobromic acid (HBr) was used as the acid solvent, and palladium bromide (PdBr2) powder was used as the metal halide.

[0194] And, a second solution was prepared in which a chiral organic substance, which is a material of a chiral organic cation, was dissolved in the acid solvent. At this time, hydrobromic acid (HBr) was used as the acid solvent, and R- / S-methylbenzylamine was used as the chiral organic substance.

[0195] Next, the second solution was slowly added to the first solution while sufficiently stirred and heated to ensure that no impurities remained, thereby completing the precursor solution of metal halide perovskite. Subsequently, the precursor solution was sufficiently heated while stirring was stopped to evaporate the solvent, and then cooled to room temperature to precipitate crystals. The size of the (R- / S-MBA)2PdBr4 crystals obtained at this time was approximately 1 to 500 mm.

[0196]

[0197] [Manufacturing Example 2: (R- / S-MBA)2Pd(Cl 0.25 Br 0.75 )4 Manufacturing of crystals]

[0198] In Manufacturing Example 1, (R- / S-MBA)2Pd(Cl) was prepared in the same manner as Manufacturing Example 1, except that the molar ratio of Cl to Br in the first solution was 0.25:0.75. 0.25 Br 0.75 )4 decision was made.

[0199]

[0200] [Manufacturing Example 3: (R- / S-MBA)2Pd(Cl 0.5 Br 0.5 )4 Manufacturing of crystals]

[0201] In Manufacturing Example 1, (R- / S-MBA)2Pd(Cl) was prepared in the same manner as Manufacturing Example 1, except that the molar ratio of Cl to Br in the first solution was 0.5:0.5. 0.5 Br 0.5 )4 decision was made.

[0202]

[0203] [Manufacturing Example 4: (R- / S-MBA)2Pd(Cl 0.75 Br 0.25 )4 Manufacturing of crystals]

[0204] In Manufacturing Example 1, (R- / S-MBA)2Pd(Cl) was prepared in the same manner as Manufacturing Example 1, except that the molar ratio of Cl to Br in the first solution was 0.75:0.25. 0.75 Br 0.25 )4 decision was made.

[0205]

[0206] [Manufacturing Example 5: Preparation of (R- / S-MBA)2PdCl4 crystals]

[0207] In Manufacturing Example 1, (R- / S-MBA)2PdCl4 crystals were obtained by performing the same method as Manufacturing Example 1, except that palladium chloride (PdCl2) powder was used as the metal halide in the first solution and hydrochloric acid (HCl) was used as the acid solvent.

[0208]

[0209] Analysis

[0210] The crystal structure information of the crystals manufactured in Manufacturing Examples 1 to 5 was measured and shown in Table 1 below.

[0211] Manufacturing Example 1 Manufacturing Example 2 Manufacturing Example 3 Manufacturing Example 4 Manufacturing Example 5 CCDC number 2 289648 2289649 2289650 23 21 88 22289652 Chemical Formula C 16 H 24 Br4N2PdC 16 H 24 Br3ClN2PdC 16 H 24 Br2Cl2N2PdC 16 H 24 BrCl3N2PdC 16 H 24Cl4N2PdChemical formula 670.41625.95581.49537.03492.57Temperature (K) 223(2) 223(2) 223(2) 223(2) 223(2) Crystal system Tetragonal Tetragonal Tetragonal Tetragonal Tetragonal Tetragonal Space group P212121P212121P212121P212121C2Z44442a(Å) 8.1152(16) 8.1090(16) 8.0960(16) 8.1073(7)11.098(2)b(Å)14.753(3)14.750(3)14.761(3)14.7871(14)7.1967(14)c(Å)17.988(4)17. 989(4)18.000(4)18.0131(17)13.243(3)α(°)9090909090β(°)9090909097.27(3)γ(°)9090909090V(Å 3 )2153.5(7)2151.6(7)2151.1(7)2159.5(3)1049.2(4)DD calc (g / cm 3 )2.0681.9321.7961.6521.5592θ max (°)51.9952.0051.9951.9952.00R1,wR2[I>2σ(I)]0.0335,0.07950.0377,0.12000.0622,0.20920.1070,0.32350.0271,0.0696R1,wR2[all data]0.0426,0.08220.0387,0.12110.0657,0.21420.1456,0.37740.0280,0.0700Goodness-of-fit on F 2 1.0751.0741.0631.0491.046No. of reflection used [>2σ(I)]6092[R int =0.0869]6092[R int =0.0662]5966[R int =0.0686]4231[R int =0.1218]2954[R int =0.0591]]Refinement227832281722784403795535D(Distortion index)1.271×10 -1 1.271×10 -1 1.272×10-1 1.282×10 -3 2.46×10 -3 σ 2 (Bond angle variance)2.912.862.822.840.9096

[0212] Figure 4 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) are pictures of the decisions.

[0213] As shown in Fig. 4, it was confirmed that a chiral lead-free metal halide perovskite crystal was produced by the production method according to the present invention. The chiral lead-free metal halide perovskite crystal exhibited a needle-like shape.

[0214]

[0215] Figure 5 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) crystals, showing the crystal structure of palladium halide.

[0216] As shown in Fig. 5, it was confirmed that the crystal structure of palladium halide is a square plane structure or a square pyramid structure, and exhibits various dimensions of one dimension and zero dimension.

[0217]

[0218] Figures 6 to 18 are (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) crystal structures of metal halides within the crystals, the helical arrangement when combined with chiral organic compounds, and the coordination environment between the metal halides and chiral organic compounds at this time are shown.

[0219] Specifically, in the (R-MBA)2PdBr4 crystal according to one embodiment of the present invention, FIG. 6 shows (a) the crystal structure of the metal halide in the crystal and (b) the helical arrangement when bonded with a chiral organic substance, FIG. 7 shows the distance between the hydrogen of the halide in the crystal and the chiral organic substance, and FIG. 8 shows the coordination environment between the metal halide and the chiral organic substance in the crystal.

[0220] Specifically, (R-MBA)2Pd(Br) according to one embodiment of the present invention 0.75 Cl 0.25 )4 In the crystal, Fig. 9 shows the (a) angle, (b) distance, and (c) helical arrangement of the crystal structure of the metal halide in the crystal when combined with a chiral organic substance, and Fig. 10 shows the coordination environment between the metal halide and the chiral organic substance in the crystal.

[0221] Specifically, (R-MBA)2Pd(Br) according to one embodiment of the present invention 0.5 Cl 0.5 ) In the 4-decision, Fig. 11 shows (a) the angle, (b) the distance, and (c) the helical arrangement when bonded with a chiral organic substance of the crystal structure of the metal halide within the crystal, Fig. 12 shows the distance between the hydrogen of the halide within the crystal and the chiral organic substance, and Fig. 13 shows the coordination environment between the metal halide within the crystal and the chiral organic substance.

[0222] Specifically, (R-MBA)2Pd(Br) according to one embodiment of the present invention 0.25 Cl 0.75 )4 In the crystal, Fig. 14 shows the angles and distances of the crystal structure of the metal halide within the crystal, and Fig. 15 shows the coordination environment between the metal halide and the chiral organic compound within the crystal.

[0223] Specifically, in the (R-MBA)2PdCl4 crystal according to one embodiment of the present invention, FIG. 16 shows the angles and distances of the crystal structure of the metal halide within the crystal, FIG. 17 shows the distance between the hydrogen of the halide and the chiral organic substance within the crystal, and FIG. 18 shows the coordination environment between the metal halide and the chiral organic substance within the crystal in the (R-MBA)2PdCl4 crystal according to one embodiment of the present invention.

[0224] As shown in FIGS. 6 to 18, (R-MBA)2Pd(Br) according to one embodiment of the present invention 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) It was confirmed that the crystal structure itself was distorted due to the electrostatic interaction between the chiral organic compound (A) and the metal halide (BX) when the metal halide in the crystal bonded with the chiral organic compound, so that the distance and angle between each atom changed, and thus a helical structure was formed.

[0225]

[0226] Figures 19 to 23 are (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) crystal structures of powders and films were measured by simulation and actual X-ray diffraction analysis (XRD).

[0227] Specifically, FIG. 19 is a simulation of (R-MBA)2PdBr4 crystals according to one embodiment of the present invention, and XRD data of powder and film, and FIG. 20 is (R-MBA)2Pd(Br 0.75 Cl 0.25 )4 decision, Fig. 21 is (R-MBA)2Pd(Br 0.5 Cl 0.5 )4 decision, Fig. 22 is (R-MBA)2Pd(Br 0.5 Cl 0.5)4 crystal, Fig. 23 is the simulation, powder and film XRD data for (R-MBA)2PdCl4 crystal.

[0228] As shown in Figures 19 to 23, (R-MBA)2Pd(Br 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) The powders of the crystals were found to be perfectly grown in agreement with the simulation, and it was confirmed that the crystals grew uniformly in the (002l) direction when forming the film.

[0229]

[0230] FIG. 24 shows the degree of excellent intralattice distortion in the crystal of (R-MBA)2PdBr4 according to one embodiment of the present invention, and FIG. 25 shows the degree of excellent intralattice distortion in the crystal of (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) represents the degree of intra-crystalline distortion.

[0231] As shown in Fig. 24, the chiral lead-based metal halide perovskite crystal according to the present invention is a perovskite formed of a conventional achiral octahedron and a perovskite formed of a chiral octahedron (CsPbI3, FA 0.875 Cs 0.125 PbI3, (IPA)2(Tz)Pb2Br7, (IPA)2(Tz)2Pb3Br 10 , (BA)2(GA)Pb2I7 and (R / S-MBA)2SnI4) were confirmed to have a superior distortion index, and as shown in Fig. 25, it was confirmed that the anisotropy factor exhibiting optical chiral properties was high when the halide composition had a composition ratio of Br and Cl of 0.5:0.5, preferably 0.4:0.6 to 0.6:0.4.

[0232]

[0233] Figure 26 is (a) (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) crystals, and (b) ultraviolet-visible (UV-Vis) spectrophotometric measurement data of films containing (R- / S-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) is a graph showing the circular dichroism characteristics of films containing the crystals.

[0234] As shown in Fig. 26, the chiral lead-free metal halide perovskite crystal according to the present invention exhibits absorption and circular dichroism of circularly polarized light at wavelengths of 300 nm to 400 nm, and also exhibits a weak signal at wavelengths of 400 nm or more, thereby confirming that chiral transition occurs within the perovskite, thereby showing chiral characteristics.

[0235]

[0236] Figure 27 is a diagram showing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) crystals, and Fig. 28 shows the crystal lattice orientation of the film containing (R-MBA)2Pd(Br) according to one embodiment of the present invention. 1-x Cl x )4(x = 0, 0.25, 0.5, 0.75 and 1) shows the variation of the interlayer spacing within the crystals of the film.

[0237] As shown in FIGS. 27 and 28, chiral lead-free metal halide perovskite crystals containing chiral organic matter, palladium, and Br exhibit crystal peaks at the same positions even when the content of Br changes, and there is almost no change in the interlayer spacing within the crystal. However, chiral lead-free metal halide perovskite crystals in which all Br is replaced with Cl exhibit changes in the positions of the crystal peaks and the interlayer spacing within the crystal.

[0238] Therefore, the chiral lead-free metal halide perovskite crystal according to the present invention changes the degree of distortion within the crystal depending on the composition of the halide, causing changes in the crystal peak and the interlayer spacing within the crystal, and thus the spin selectivity can be controlled by utilizing this.

[0239]

[0240] Figure 29 shows the chirality-induced spin selectivity of a (R- / S-MBA)2PdBr4 film according to one embodiment of the present invention. The chirality-induced spin selectivity was measured using a magnetic-conductive atomic force microscope (mcp-AFM).

[0241] As shown in Fig. 29, it was confirmed that a film made of a chiral lead-free metal halide perovskite crystal according to the present invention exhibits a difference in the current flowing by spin due to chirality even without an additional external magnetic field, and from this, it was confirmed that it has chirality-induced spin selectivity.

[0242]

[0243] [Preparation Example 6: (R- / S-MBA)4Bi2I 10 [Making of decisions]

[0244] In Manufacturing Example 1, the same method as Manufacturing Example 1 was performed except that hydroiodic acid (HI) was used as the acid solvent of the first solution and the second solution, and bismuth iodide (BiI3) powder was used as the metal halide of the first solution, thereby obtaining (R- / S-MBA)4Bi2I.10 I got the decision.

[0245]

[0246] [Manufacturing Example 7: (R- / S-MBA)4Bi2Br 10 [Making of decisions]

[0247] In Manufacturing Example 1, the same method as Manufacturing Example 1 was performed except that hydrobromic acid (HBr) was used as the acid solvent of the first solution and the second solution, and bismuth bromide (BiBr3) powder was used as the metal halide of the first solution, thereby obtaining (R- / S-MBA)4Bi2Br. 10 I got the decision.

[0248]

[0249] [Preparation Example 8: (R- / S-MBA)4Bi2Cl 10 [Making of decisions]

[0250] In Manufacturing Example 1, the same method as Manufacturing Example 1 was performed except that hydrochloric acid (HCl) was used as the acid solvent of the first solution and the second solution, and bismuth chloride (BiCl3) powder was used as the metal halide of the first solution, thereby obtaining (R- / S-MBA)4Bi2Cl. 10 I got the decision.

[0251]

[0252] Analysis

[0253] Figure 30 is (R-MBA)4Bi2I according to one embodiment of the present invention. 10 , (R-MBA)4Bi2Br 10 and (R-MBA)4Bi2Cl 10 Indicates the shape of the decision.

[0254] As shown in Fig. 30, it was confirmed that the chiral lead-free metal halide perovskites manufactured in Figs. 6 to 8 formed crystals of various sizes.

[0255]

[0256] Figure 31 is (S-MBA)4Bi2I according to one embodiment of the present invention. 10and (R-MBA)4Bi2Br 10 It shows the crystal structure.

[0257] As shown in Figure 31, it was confirmed that the interaction between the chiral organic material and the metal halide structure differs depending on the halide composition of the manufactured chiral lead-free metal halide perovskite, and this appears as a change in the distortion of the crystal structure.

[0258]

[0259] Figures 32 to 34 are (R- / S-MBA)4Bi2I according to one embodiment of the present invention. 10 , (R- / S-MBA)4Bi2Br 10 and (R- / S-MBA)4Bi2Cl 10 This is a graph showing the circular dichroism characteristics of the crystals and data measured using an ultraviolet-visible (UV-Vis) spectrophotometer.

[0260] As shown in Figures 32 to 34, the chiral lead-free metal halide perovskite according to the present invention exhibits circular dichroism characteristics depending on the distortion of the crystal structure, and it was confirmed that the degree of distortion of the crystal structure differs depending on the halide composition, and therefore the degree of circular dichroism differs accordingly.

[0261]

[0262] [Manufacturing Examples 9-44]

[0263] In Manufacturing Example 1, a chiral lead-free metal halide perovskite crystal having spin selectivity was obtained by performing the same method as Manufacturing Example 1, except that the chiral organic material disclosed in Tables 2 and 3 below was used as the chiral organic material in the second solution.

[0264] Example 9 of manufacturing chiral organic compounds (S)-form (R)-form Manufacturing Example 10 Manufacturing Example 11 Manufacturing Example 12 Manufacturing Example 13 Manufacturing Example 14 Manufacturing Example 15 Manufacturing Example 16 Manufacturing Example 17 Manufacturing Example 18 Manufacturing Example 19 Manufacturing Example 20 Manufacturing Example 21 Manufacturing Example 22 Manufacturing Example 23 Manufacturing Example 24 Manufacturing Example 25 Manufacturing Example 26 Manufacturing Example 27 Manufacturing Example 28

[0265] Example 29 of manufacturing chiral organic compounds (S)-form (R)-form Manufacturing Example 30 Manufacturing Example 31 Manufacturing Example 32 Manufacturing Example 33 Manufacturing Example 34 Manufacturing Example 35 Manufacturing Example 36 Manufacturing Example 37 Manufacturing Example 38 Manufacturing Example 39 Manufacturing Example 40 Manufacturing Example 41 Manufacturing Example 42 Manufacturing Example 43 Manufacturing Example 44

[0266] While the present invention has been described with reference to preferred embodiments, it should be understood that the present invention is not limited to these embodiments. The present invention may be modified and adapted in various ways within the scope of the claims, all of which fall within the scope of the present invention. Accordingly, the present invention is limited only by the claims and their equivalents.

Claims

1. ABX3, A'2A n-1 BX 3n+1 , ABX4, A2BX 4, A2BX5, A3BX5, A4B2X 10 , ABX5, A3B2X9, AB2X 10 Or a perovskite having the chemical formula A2B1B'X6, A is a chiral organic cation or a combination of different chiral organic cations, A' is a chiral organic cation different from A, or an achiral organic cation, B and B' are metal ions other than Pb, organic cations, inorganic cations, ammonium ions, or combinations thereof, X is F - , Cl - , Br - , I - or a combination of these, n is an integer from 1 to 10, The above perovskite has BX6 octahedral, BX5 square pyramidal, BX4 tetrahedral or BX4 planar square unit layers and A unit layers bonded to X by electrostatic attraction alternately arranged, The chirality of A is characterized by transferring to the BX6 octahedron, BX5 square pyramid, BX4 tetrahedron or BX4 planar square unit layer by the electrostatic attraction, thereby having chirality-induced spin polarization current selectivity. Chiral lead-free metal halide perovskites.

2. In paragraph 1, A chiral lead-free metal halide perovskite, characterized in that the chiral organic cation is a cation represented by the following chemical formula A or chemical formula B. [Chemical Formula A] [Chemical Formula B] (In the above chemical formulas A and B, R a and R b are independently substituted or unsubstituted C1~C 10 Alkyl, C3~C 10 Cycloalkyl, C3~C 10 Heterocycloalkyl, C6~C 12 Aryl, C6~C 12 Heteroaryl or C6~C 12 Heteroaryl-C1~C 10 is alkyl, and the heterocycloalkyl or heteroaryl contains N, O, S, P or Se in the ring, The above R a Wow R b are different, The above R a Wow R b can be combined with each other to form rings, R c is NH3 + , RNH3 + , (CH2) n NH3 + , COOH, (CH2) n COOH, OH or CH3, The above R c COOH, (CH2) n If COOH, OH or CH3, R a is RNH3 + , (CH2) n NH3 + or NH3 + is replaced by, Here, R is substituted or unsubstituted C1~C 10 Alkyl, C3~C 10 Cycloalkyl, C3~C 10 Heterocycloalkyl, C6~C 12 Aryl, C6~C 12 Heteroaryl or C6~C 12 Heteroaryl-C1~C 10 is alkyl, and the heterocycloalkyl or heteroaryl contains N, O, S, P or Se in the ring, and n is an integer from 1 to 10, * is a chiral central carbon.) 3. In paragraph 2, The above R a and R b A chiral lead-free metal halide perovskite, characterized in that the cycloalkyl, heterocycloalkyl, aryl or heteroaryl is substituted with halogen, C1~C2 alkyl or C1~C2 alkoxy.

4. In paragraph 2, A chiral lead-free metal halide perovskite, characterized in that the chiral organic cation is a cation represented by the following chemical formula A-1 or chemical formula B-1. [Chemical Formula A-1] [Chemical Formula B-1] (In the above chemical formulas A-1 and B-1, The above R a , R b and * are as defined in the above chemical formulas A and B.) 5. In paragraph 4, A chiral lead-free metal halide perovskite, characterized in that the chiral organic cation is selected from the following group.

6. In paragraph 1, A chiral lead-free metal halide perovskite, characterized in that the chiral organic cation is a cation represented by the following chemical formula A-2 or chemical formula B-2. [Chemical Formula A-2] [Chemical Formula B-2] (In the above chemical formulas A-2 and B-2, R c is NH3 + , RNH3 + , (CH2) n NH3 + , COOH, (CH2) n COOH, OH or CH3, R d C5~C which does not have a plane of symmetry based on the chiral center carbon 12 Cycloalkyl or C5~C 12 is heterocycloalkyl, wherein said heterocycloalkyl contains N, O, S, P or Se in the ring, The above cycloalkyl or the above heterocycloalkyl is C6~C 12 It can be fused with aryl, The above R c COOH, (CH2) n If COOH, OH or CH3, the above R d NH within the ring + or NH2 + RNH3 as a substituent substituted with or bonded to the ring + , (CH2) n NH3 + or NH3 + has a substituent, Here, R is substituted or unsubstituted C1~C 10 Alkyl, C3~C 10 Cycloalkyl, C3~C 10 Heterocycloalkyl, C6~C 12 Aryl, C6~C 12 Heteroaryl or C6~C 12 Heteroaryl-C1~C 10 is alkyl, and the heterocycloalkyl or heteroaryl contains N, O, S, P or Se in the ring, and n is an integer from 1 to 10, * is a chiral central carbon.) 7. In paragraph 6, A chiral lead-free metal halide perovskite, characterized in that the chiral organic cation is selected from the following group.

8. In paragraph 1, The above achiral organic cation is R e NH3 + And, R e is characterized by being C1~C6 alkyl or C1~C6 haloalkyl, Chiral lead-free metal halide perovskites.

9. In paragraph 1, The above B and B' are independently selected from the group consisting of Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Rb, Sr, Y, Zr, Nb, Mo, Tc, Ru, Rh, Pd, La, Ce, Pr, Nd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Hf, Ta, W, Re, Os, Ir, Pt, Th, Pa, U, Pu, Am, Si, Zn, Ga, As, Se, Ag, Cd, In, Sn, Sb, Te, Au, Hg, Tl and Bi, characterized in that they are selected from the group consisting of cations of elements, organic cations, inorganic cations and ammonium ions. Chiral lead-free metal halide perovskites.

10. In paragraph 1, The above B and B' are characterized in that they independently have an octahedron, a tetrahedra, a square plane structure, or a square pyramid structure. Chiral lead-free metal halide perovskites.

11. In paragraph 1, The above chiral lead-free metal halide perovskite is characterized by having a BX6 octahedral, BX5 square pyramidal, BX4 tetrahedral or BX4 planar square unit layer and an A unit layer bonded to X by electrostatic attraction in a twisted manner, thereby having a spiral structure arrangement within the crystal. Chiral lead-free metal halide perovskites.

12. In paragraph 11, The above chiral lead-free metal halide perovskite is characterized in that the degree of twisting of the helical structure within the perovskite crystal is controlled by controlling the composition of X. Chiral lead-free metal halide perovskites.

13. In paragraph 1, The above chiral lead-free metal halide perovskite is characterized by a crystal size of 1 nm to 500 cm.

14. In paragraph 1, A chiral lead-free metal halide perovskite, characterized in that the chiral lead-free metal halide perovskite has a three-dimensional (3D), two-dimensional (2D), one-dimensional (1D), or zero-dimensional (0D) structure.

15. In paragraph 1, A chiral lead-free metal halide perovskite characterized in that the chiral lead-free metal halide perovskite exhibits circular dichroism in the range of 200 nm to 1000 nm.

16. In paragraph 1, The above chiral lead-free metal halide perovskites are C1, P1, C2, P121, P1211, C121, D2, P222, P2221, P21212, P212121, C2221, C222, F222, I222, I212121, C4, P4 , P41, P42, P43, I4, I41, D4, P422, P4212, P4122, P41212, P4222, P42212, P4322, P43212, I422, I4122, C3, P3, P31, P32, R3, D3, P312, P321, P3112, P3121, P3212, P32 21,R32,C6,P6,P61,P65,P62,P64,P63,D6,P622,P6122,P6522,P6222,P6422,P6322,T,P23,F23,I23,P213,I213,O,P432,P4232,F432,F4132,I432,P4332,P4132 or I4132 having a point group or space group, Chiral lead-free metal halide perovskites.

17. In paragraph 1, The chiral lead-free metal halide perovskite is characterized in that the crystal is formed through a solvent evaporation method, an antisolvent vapor-assisted method, an inverse temperature crystallization method, a bridgman method, a hydrothermal method, a mechanochemical reaction method, a solvent-mediated method, or a space-confined method.

18. A device comprising the chiral lead-free metal halide perovskite of paragraph 1.

19. In paragraph 18, A device characterized in that the device is a spin light-emitting diode, a photosensor device, a solar cell, a memory device, or a water electrolytic cell.

20. A perovskite crystal in which BX6 octahedral, BX5 square pyramidal, BX4 tetrahedral or BX4 planar square unit layers and A unit layers bonded to X by electrostatic attraction are alternately arranged, A is a chiral organic cation, B is a metal ion other than Pb, X is F - , Cl - , Br - , I - or a combination of these, The chirality of A is transferred to the BX6 octahedron, BX5 square pyramid, BX4 tetrahedron or BX4 planar square unit layer by the electrostatic attraction, The spin direction of the conduction electrons is determined by the internal magnetic field formed by the mutual influence of the conduction electrons and the chiral crystal under an electric field. A metal halide perovskite crystal characterized by spin polarization current selectivity in the absence of an external magnetic field.

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