Phosphate ester compound taking 1, 3, 5-triazine or pyrimidine as core and application of phosphate ester compound in perovskite luminescent device

Abstract

The invention provides a phosphate ester compound taking 1, 3, 5-triazine or pyrimidine as a core and application of the phosphate ester compound in a perovskite light-emitting device, and the structure of the compound is as shown in a formula (I). 1, 3, 5-triazine or pyrimidine is taken as a molecular core, so that a good electron transmission effect is achieved; peripheral phosphate groups can be coordinated with lead atoms, so that the defect state density is reduced, and therefore, the compound disclosed by the invention has the functions of electron transport and passivation of perovskite materials. On one hand, the compound can be applied to a perovskite light-emitting layer to serve as a passivator, and electron transmission can be promoted while defects are passivated; on the other hand, the material can be used as an electron transport material to transport electrons to a light-emitting layer, and interface defects between the light-emitting layer and an electron transport layer can be passivated. The compound with the electron transport and passivation effects is applied to a perovskite light-emitting device, and the compound can be used as a passivator to be added to a light-emitting layer and used as an electron transport material to prepare an electron transport layer, so that the performance of the perovskite light-emitting device can be improved. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to the field of perovskite light-emitting devices, and in particular to a phosphate compound with 1,3,5-triazine or pyrimidine as a core and application thereof in perovskite light-emitting devices. Background Art

[0002] Perovskite luminescent materials have the characteristics of high luminous efficiency, easy adjustment of luminescent color, high color purity, wide material sources and solution processing. They have been widely used in light-emitting devices and are the core elements of new display technologies. Usually, there are many defects and traps on the surface of perovskite films, forming non-radiative recombination centers, which leads to reduced luminous efficiency. Most of the defects on the surface of perovskites are caused by uncoordinated lead atoms. Introducing passivators to passivate uncoordinated lead atoms and reduce defect density is an effective means to improve luminous efficiency. At present, most of the passivators used are electronically inert materials, which do not have carrier transport effects, and often lead to a decrease in the carrier transport rate in the light-emitting layer, showing an increase in device voltage. On the other hand, for common devices, the interface defects between the light-emitting layer and the electron transport material will also lead to a decrease in the efficiency of perovskite light-emitting devices. Therefore, the development of electron transport materials with passivation effects is expected to further improve the performance of perovskite light-emitting devices. Summary of the invention

[0003] In view of the deficiencies of the prior art, the present invention provides a phosphate compound with 1,3,5-triazine or pyrimidine as the core and its application in perovskite light-emitting devices. The compound is based on 1,3,5-triazine or pyrimidine as the molecular core and has a good electron transport effect; its peripheral phosphate group can coordinate with lead atoms to reduce the defect state density, so that it has both the function of electron transport and passivation of perovskite materials. On the one hand, the compound of the present invention can be used in the perovskite light-emitting layer as a passivator, which can promote electron transport while passivating defects; on the other hand, it can be used as an electron transport material to transfer electrons to the light-emitting layer, and at the same time, it can passivate the interface defects between the light-emitting layer and the electron transport layer. In general, the present invention provides a compound with both electron transport and passivation effects, which can be added to the light-emitting layer as a passivator, and can also be used as an electron transport material to prepare an electron transport layer, both of which can achieve the improvement of the performance of perovskite light-emitting devices.

[0004] To achieve the above objectives, the present invention adopts the following technical solutions:

[0005] The present invention provides a phosphate compound with 1,3,5-triazine or pyrimidine as the core, and its structure is shown in formula (I):

[0006]

[0007] Wherein, X1 is selected from a C atom or a N atom;

[0008] When X1 is a C atom, formula (I) represents a phosphate compound with pyrimidine as the core, having a structure shown in formula (I-1);

[0009]

[0010] When X1 is a N atom, formula (I) represents a phosphate compound with 1,3,5-triazine as the core, having a structure shown in formula (I-2);

[0011]

[0012] Y1, Y2, and Y3 are each independently selected from an O or S atom; n is selected from an integer of 0-2, m is selected from an integer of 1-3, and the sum of n and m is 3; k represents The number of phosphate groups on the

[0013] Each is independently selected from a substituted or unsubstituted C6-C60 aromatic ring group, a substituted or unsubstituted C5-C60 aromatic heterocyclic group, and the dotted line between the groups indicates that the groups can be bonded at any position;

[0014] R1 and R2 are each independently selected from a C1-C30 straight-chain hydrocarbon group, a C3-C30 branched hydrocarbon group, a C3-C30 cyclic hydrocarbon group, a C1-C30 halogenated hydrocarbon group, a substituted or unsubstituted C6-C60 aromatic group, or a substituted or unsubstituted C5-C60 heteroaromatic group;

[0015] Furthermore, non-adjacent carbon atoms in the straight-chain hydrocarbon group, branched hydrocarbon group, cyclic hydrocarbon group, and halogenated hydrocarbon group can also be substituted by O, S, Si, or -CO-O-;

[0016] Preferably, the heteroatoms in the heteroaromatic group are selected from one or more of Si, Ge, S, O, Se, N and P;

[0017] Preferably, the substituents in the substituted C6-C60 aromatic ring group or the substituted C5-C60 heteroaromatic group are independently selected from H, D, F, Cl, Br, I, -CN, -NO2, -OR 1 、-SR 1 , -Se-R 1 , -Te-R 1 , A C1-C30 straight chain hydrocarbon group, a C3-C30 branched hydrocarbon group, a C3-C30 cyclic hydrocarbon group, a C6-C60 aromatic group, or a C5-C60 heteroaromatic group;

[0018] Among them, R 1 , R 2 and R 3 R is the same or different at each occurrence and is independently selected from the following groups: (i) H, halogen, -CN, -NO2, -OH, C1-C30 straight chain hydrocarbon group, C3-C30 branched hydrocarbon group, C3-C30 cyclic hydrocarbon group, C1-C30 alkoxy chain, C1-C30 halogenated hydrocarbon group, (ii) substituted or unsubstituted C6-C60 aromatic ring group, substituted or unsubstituted C5-C60 heteroaromatic ring group; 1 , R 2 and R 3 They can also be connected by chemical bonds to form a bridge structure.

[0019] Furthermore, one or more non-adjacent carbon atoms in the straight-chain hydrocarbon group, branched hydrocarbon group, cyclic hydrocarbon group, alkoxy chain, and halogenated hydrocarbon group may be substituted by O, S, Si, or -CO-O-;

[0020] Preferably, Each is independently selected from the following structures:

[0021]

[0022]

[0023] Wherein, L1, L2 and L3 are the same or different each time they appear, and are independently selected from the following groups: (i) H, halogen, -CN, -NO2, -OH, a C1-C30 straight-chain hydrocarbon group, a C3-C30 branched hydrocarbon group, a C3-C30 cyclic hydrocarbon group, a C1-C30 alkoxy chain, a C1-C30 halogenated hydrocarbon group, (ii) a substituted or unsubstituted C6-C60 aromatic ring group, a substituted or unsubstituted C5-C60 heteroaromatic ring group; L1, L2 and L3 can also be connected by chemical bonds to form a bridge structure.

[0024] Furthermore, one or more non-adjacent carbon atoms in the straight-chain hydrocarbon group, branched hydrocarbon group, cyclic hydrocarbon group, alkoxy chain, and halogenated hydrocarbon group may be substituted by O, S, Si, or -CO-O-.

[0025] More preferably, Each is independently selected from the following structures:

[0026]

[0027] In the above technical solution, it is further preferred that the phosphate compound with 1,3,5-triazine or pyrimidine as the core has one of the structures shown in Formula B1 to Formula B105:

[0028]

[0029]

[0030]

[0031] The present invention also provides a method for preparing a phosphate compound with 1,3,5-triazine or pyrimidine as the core, which specifically comprises the following steps:

[0032] The target compound (I) is prepared by a Pd-catalyzed phosphorylation reaction of an aromatic halide (Formula (II)) with 1,3,5-triazine or pyrimidine as the molecular core and a phosphate (Formula (III));

[0033]

[0034] Wherein, Lu is a halogen, preferably Br or I, and k is The number of halogens on the surface; The definitions of X1, n, and m are consistent with those of the above compound formula (I), and will not be repeated here;

[0035]

[0036] Wherein, the definitions of R1, R2, Y1, Y2 and Y3 are consistent with those of the above compound formula (I) and are not repeated here.

[0037] Preferably, the reaction temperature of the Pd-catalyzed phosphating reaction is 50-68° C., the catalytic system is palladium acetate / dppf / potassium acetate / triethylamine / THF or Pd(PPh3)4 / N-methylmorpholine / toluene, and the reaction time is 1.5 to 12 h.

[0038] The present invention also provides the use of the phosphate compound with 1,3,5-triazine or pyrimidine as the core as shown in the above formula (I) in a perovskite light-emitting device.

[0039] The present invention also provides a perovskite light-emitting device, wherein at least one of the perovskite light-emitting layer or the electron transport layer of the perovskite light-emitting device comprises a phosphate compound with 1,3,5-triazine or pyrimidine as the core as shown in the above formula (I);

[0040] Furthermore, the perovskite thin film light-emitting layer in the perovskite light-emitting device contains a phosphate compound with 1,3,5-triazine or pyrimidine as the core as the additive represented by the above formula (I) of the present invention.

[0041] Furthermore, the electron transport layer in the perovskite light-emitting device comprises a phosphate compound with 1,3,5-triazine or pyrimidine as the core represented by the above formula (I) of the present invention as an electron transport material.

[0042] The present invention has no particular limitation on the structure of the above-mentioned perovskite light-emitting device, and any conventional perovskite light-emitting device familiar to those skilled in the art may be used. Those skilled in the art may select and adjust the structure according to the application, quality requirements and product requirements.

[0043] Preferably, the structure of the perovskite light-emitting device of the present invention includes, in sequence: a substrate, an anode, a hole injection layer, a hole transport layer, a perovskite light-emitting layer, an electron transport layer, an electron injection layer, and a cathode.

[0044] The present invention has no particular limitation on the selection of the substrate, and any conventional organic electroluminescent device substrate known to those skilled in the art can be used. Those skilled in the art can select and adjust the substrate according to the application, quality requirements and product requirements. In the present invention, the substrate is preferably glass or plastic.

[0045] Furthermore, the thickness of the substrate is preferably 0.3-0.7 mm, more preferably 0.4-0.6 mm.

[0046] According to the present invention, the anode is preferably a material that is easy for hole injection, more preferably a conductive metal or a conductive metal oxide, and even more preferably indium tin oxide.

[0047] The present invention has no particular restrictions on the materials and thickness of the hole injection layer and hole transport layer, and can be selected and adjusted according to the materials and thicknesses known to those skilled in the art. The preferred hole injection layer is composed of PEDOT:PSS, and the preferred hole transport layer is composed of PVK or TFB.

[0048] In the present invention, the perovskite light-emitting layer contains a phosphate compound with 1,3,5-triazine or pyrimidine as the core as an additive, or the electron transport layer contains a phosphate compound with 1,3,5-triazine or pyrimidine as the core as the electron transport material.

[0049] The present invention has no limitation on the perovskite light-emitting material in the perovskite light-emitting layer and the thickness of the perovskite light-emitting layer, which can be selected and adjusted according to the materials and thicknesses known to those skilled in the art.

[0050] The present invention has no particular restrictions on the material and thickness of the electron injection layer, which can be selected and adjusted according to the materials and thicknesses known to those skilled in the art. Preferred electron injection materials are lithium fluoride, sodium fluoride, cesium carbonate, and metallic calcium.

[0051] The cathode is preferably a metal, including but not limited to calcium, magnesium, barium, aluminum and silver, preferably aluminum.

[0052] In order to improve the performance and efficiency of the device, an electron blocking layer is preferably included between the anode and the light-emitting layer, and a hole blocking layer is preferably included between the light-emitting layer and the cathode. The present invention has no particular restrictions on the preparation process of the hole injection layer, hole transport layer, electron blocking layer, perovskite light-emitting layer, hole blocking layer, electron injection layer and electron transport layer, and a suitable process can be selected according to the material characteristics for preparation.

[0053] Beneficial effects of the present invention:

[0054] The present invention provides a phosphate compound with 1,3,5-triazine or pyrimidine as the core, the structure of which is shown in formula (I), and the phosphate compound is used as an additive of a perovskite light-emitting layer or an electron transport material in a perovskite light-emitting device.

[0055] Compared with the prior art, the present invention has the following advantages:

[0056] The present invention uses a phosphate compound with 1,3,5-triazine or pyrimidine as the core as a perovskite light-emitting layer additive. The peripheral phosphate group can passivate the unsaturated coordinated lead defects in the perovskite lattice, reduce the defect state density, reduce non-radiative energy loss, and improve the fluorescence quantum yield of the perovskite film. It can also utilize the strong electron transport properties of the central 1,3,5-triazine or pyrimidine unit to promote the transport and recombination of carriers, thereby overcoming the problem of reduced carrier transport efficiency caused by the introduction of traditional electronic inert passivators.

[0057] The present invention uses a phosphate compound with 1,3,5-triazine or pyrimidine as the core as the electron transport material of the perovskite light-emitting device. The central 1,3,5-triazine or pyrimidine unit has a strong electron transport property, and different substituents are introduced to regulate the electron mobility that matches the hole transport material. The peripheral phosphate group can passivate the unsaturated coordinated lead defects at the interface of the perovskite light-emitting layer, reduce the interface trap density, reduce the non-radiative energy loss, and improve the device performance.

[0058] The present invention provides a compound having both electron transport and passivation effects, which can be used as a passivator in a light-emitting layer, or as an electron transport material to prepare an electron transport layer, both of which can improve the performance of perovskite light-emitting devices. At the same time, the present invention provides a new material design scheme for the development of high-performance perovskite optoelectronic devices. DETAILED DESCRIPTION

[0059] The technical solution of the present invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0060] Unless otherwise defined, all professional terms used hereinafter have the same meanings as those generally understood by those skilled in the art. The professional terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention; unless otherwise specifically stated, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or prepared by existing methods.

[0061] Example 1

[0062] The reaction formula is as follows:

[0063]

[0064] 2-(4-bromophenyl)-4,6-diphenylpyrimidine (3.87 g, 10 mmol) and diethyl phosphite (1.68 g, 12 mmol), 1-1'-bis(diphenylphosphino)ferrocene (0.67 g, 1.2 mmol), potassium acetate (3.53 g, 36 mmol), palladium acetate (0.13 g, 0.6 mmol) and triethylamine (1 mL) were dissolved in anhydrous THF (25 mL) and ventilated three times under vacuum. The reaction system was heated to 75 ° C and stirred for 8 hours. After the reaction was cooled to room temperature, the solvent was removed under reduced pressure and separated and purified by silica gel column chromatography (petroleum ether / ethyl acetate = 1:1) to obtain B1, 3.69 g of white solid, yield: 86%. Elemental analysis structure (C 26 H 25 N2O3P): theoretical value C, 70.26; H, 5.67; N, 6.30; P, 6.97; measured value C, 70.46; H, 5.87; N, 6.12; P, 6.75; MALDI-TOF mass spectrum: theoretical value 444.2; experimental value 444.1 (M + ).

[0065] Example 2

[0066]

[0067] The preparation conditions and feed ratio of compound B2 are the same as those of compound B1. It is only necessary to replace the reactant 2-(4-bromophenyl)-4,6-diphenylpyrimidine with 2-(4-bromophenyl)-4,6-diphenyl-1,3,5-triazine. The product is a white solid with a yield of 82%. Elemental analysis structure (C 25 H 24 N3O3P): theoretical value C, 67.41; H, 5.43; N, 9.43; P, 6.95; measured value C, 67.88; H, 5.87; N, 9.23; P, 6.78; MALDI-TOF mass spectrum: theoretical value 445.2; experimental value 445.2 (M + ).

[0068] Example 3

[0069]

[0070] 2,4-bis(4-bromophenyl)-6-phenyl-1,3,5-triazine (4.67 g, 10 mmol) and diethyl phosphite (3.31 g, 24 mmol), 1-1'-bis(diphenylphosphino)ferrocene (1.33 g, 2.4 mmol), potassium acetate (7.07 g, 72 mmol), palladium acetate (0.27 g, 1.2 mmol) and triethylamine (1 mL) were dissolved in anhydrous THF (25 mL) and ventilated three times under vacuum. The reaction system was heated to 75 ° C and stirred for 8 hours. After the reaction was cooled to room temperature, the solvent was removed under reduced pressure and separated and purified by silica gel column chromatography (petroleum ether / ethyl acetate = 1:1) to obtain B3, 4.30 g of white solid, yield: 74%. Elemental analysis structure (C 29 H 33 N3O6P2): theoretical value C, 59.90; H, 5.72; N, 7.23; P, 10.65; measured value C, 59.73; H, 5.81; N, 7.31; P, 10.39; MALDI-TOF mass spectrum: theoretical value 581.2; experimental value 581.2 (M + ).

[0071] Example 4

[0072]

[0073] 2,4,6-tris(4-bromophenyl)-1,3,5-triazine (5.46 g, 10 mmol) and diethyl phosphite (3.31 g, 24 mmol), 1-1'-bis(diphenylphosphino)ferrocene (2.00 g, 3.6 mmol), potassium acetate (7.07 g, 72 mmol), palladium acetate (0.40 g, 1.8 mmol) and triethylamine (1.2 mL) were dissolved in anhydrous THF (40 mL) and ventilated three times under vacuum. The reaction system was heated to 75 °C and stirred for 8 hours. After the reaction was cooled to room temperature, the solvent was removed under reduced pressure and separated and purified by silica gel column chromatography (petroleum ether / ethyl acetate = 1:1) to obtain B4, 4.88 g of white solid, yield: 68%. Elemental analysis structure (C 33 H 42 N3O9P3): theoretical value C, 55.23; H, 5.90; N, 5.86; P, 12.95; measured value C, 55.73; H, 5.81; N, 6.31; P, 12.39; MALDI-TOF mass spectrum: theoretical value 717.6; experimental value 717.6 (M + ).

[0074] Example 5

[0075]

[0076] The preparation conditions and feed ratio of compound B5 are the same as those of compound B4, except that the reactant 2,4,6-tris(4-bromophenyl)-1,3,5-triazine is replaced by 2,4,6-tris(4-bromophenyl)pyrimidine. The product is a white solid with a yield of 68%. Elemental analysis structure (C 34 H 43 N2O9P3): theoretical value C, 56.98; H, 6.05; N, 3.91; P, 12.97 test value C, 56.74; H, 5.87; N, 4.23; P, 12.78; MALDI-TOF mass spectrum: theoretical value 716.2; experimental value 716.2 (M + ).

[0077] Example 6

[0078]

[0079] The preparation conditions and feed ratio of compound B6 are the same as those of compound B4. It is only necessary to replace the reactant 2,4,6-tris(4-bromophenyl)-1,3,5-triazine with 2,4,6-tris(3-bromophenyl)-1,3,5-triazine. The product is a white solid with a yield of 64%. Elemental analysis structure (C 33 H 42N3O9P3): theoretical value C, 55.23; H, 5.90; N, 5.86; P, 12.95 test value C, 55.64; H, 5.87; N, 5.71; P, 13.01; MALDI-TOF mass spectrum: theoretical value 717.2; experimental value 717.2 (M + ).

[0080] Example 7

[0081]

[0082] The preparation conditions and feed ratio of compound B44 are consistent with those of compound B4, except that the reactant 2,4,6-tris(4-bromophenyl)-1,3,5-triazine is replaced by 2-(2-bromo-9,9'-spiro[fluorene]-6-yl)-4,6-bis(2-bromo-9,9'-spiro[fluorene]-7-yl)-1,3,5-triazine. The product is a white solid with a yield of 58%. Elemental analysis structure (C 90 H 72 N3O9P3): theoretical value C, 75.46; H, 5.07; N, 2.93; P, 6.49 test value C, 75.64; H, 5.66; N, 2.71; P, 6.74; MALDI-TOF mass spectrum: theoretical value 1431.5; experimental value 1431.5 (M + ).

[0083] Example 8

[0084]

[0085] The preparation conditions and feed ratio of compound B45 are consistent with those of compound B4. It is only necessary to replace the reactant 2,4,6-tris(4-bromophenyl)-1,3,5-triazine with the reactant 2-(2-bromo-9,9'-spiro[fluorene]-6-yl)-4,6-bis(2-bromo-9,9'-spiro[fluorene]-7-yl)pyrimidine. The product is a white solid with a yield of 62%. Elemental analysis structure (C 91 H 73 N2O9P3): Theoretical value: C, 76.35; H, 5.14; N, 1.96; P, 6.49 Test value C, 75.94; H, 5.26; N, 2.01; P, 6.64; MALDI-TOF mass spectrum: Theoretical value 1430.4; Expected value 1430.4 (M + ).

[0086] Example 9

[0087]

[0088] The preparation conditions and feed ratio of compound B46 are consistent with those of compound B3. It is only necessary to replace the reactant 2,4-bis(4-bromophenyl)-6-phenyl-1,3,5-triazine with the reactant 2-(9,9'-spiro[fluorene]-3-yl)-4,6-bis(2-bromo-9,9'-spiro[fluorene]-7-yl)-1,3,5-triazine. The product is a white solid with a yield of 57%. Elemental analysis structure (C 86 H 63 N3O6P2): Theoretical value: C, 79.68; H, 4.90; N, 3.24; P, 4.78 Test value C, 79.94; H, 5.02; N, 3.31; P, 4.64; MALDI-TOF mass spectrum: Theoretical value 1295.4; Expected value 1295.4 (M + ).

[0089] Example 10

[0090]

[0091] The preparation conditions and feed ratio of compound B47 are consistent with those of compound B3. It is only necessary to replace the reactant 2,4-bis(4-bromophenyl)-6-phenyl-1,3,5-triazine with the reactant 2-(9,9'-spiro[fluorene]-3-yl)-4,6-bis(2-bromo-9,9'-spiro[fluorene]-7-yl)pyrimidine. The product is a white solid with a yield of 69%. Elemental analysis structure (C 87 H 64 N2O6P2): Theoretical value: C, 80.67; H, 4.98; N, 2.16; P, 4.78 Test value C, 80.14; H, 5.05; N, 2.31; P, 4.84; MALDI-TOF mass spectrum: Theoretical value 1294.4; Expected value 1294.4 (M + ).

[0092] Embodiment 11

[0093]

[0094] ((1,3,5-triazine-2,4,6-triyl)tri(benzene-4,1-diyl))tri(bis(4-bromophenyl)phosphine oxide) (13.83 g, 10 mmol) and diethyl phosphite (9.94 g, 72 mmol), 1-1'-bis(diphenylphosphino)ferrocene (3.99 g, 7.2 mmol), potassium acetate (21.20 g, 216 mmol), palladium acetate (0.81 g, 3.6 mmol) and triethylamine (1.5 mL) were dissolved in anhydrous THF (40 mL) and ventilated three times under vacuum. The reaction system was heated to 75 ° C and stirred for 8 hours. After the reaction was cooled to room temperature, the solvent was removed under reduced pressure and separated and purified by silica gel column chromatography (petroleum ether / ethyl acetate = 1:2) to obtain B48, a white solid of 10.01 g, with a yield of 58%. Elemental analysis structure (C 81 H 96 N3O 21 P9): theoretical value C, 56.35; H, 5.61; N, 2.43; P, 16.15; measured value C, 56.73; H, 5.81; N, 2.31; P, 16.69; MALDI-TOF mass spectrum: theoretical value 1725.4; experimental value 1725.4 (M + ).

[0095] Example 12

[0096]

[0097] The preparation conditions and feed ratio of compound B49 are consistent with those of compound B48. It is only necessary to replace the reactant ((1,3,5-triazine-2,4,6-triyl)tris(benzene-4,1-diyl))tris(bis(4-bromophenyl)phosphine oxide) with (pyrimidine-2,4,6-triyltris(benzene-4,1-diyl))tris(bis(4-bromophenyl)phosphine oxide). The product is a white solid with a yield of 69%. Elemental analysis structure (C 82 H 97 N2O 21 P9): Theoretical value: C, 57.08; H, 5.67; N, 1.62; P, 16.16 Test value C, 57.14; H, 5.55; N, 1.51; P, 15.84; MALDI-TOF mass spectrum: Theoretical value 1724.4; Expected value 1724.4 (M + ).

[0098] Embodiment 13

[0099]

[0100] (6-(4-(diphenylphosphoryl)phenyl)-1,3,5-triazine-2,4-diyl)bis(4,1-phenylene))bis(bis(4-bromophenyl)phosphine oxide) (12.25 g, 10 mmol) and diethyl phosphite (6.62 g, 48 mmol), 1-1'-bis(diphenylphosphino)ferrocene (2.66 g, 4.8 mmol), potassium acetate (14.13 g, 144 mmol), palladium acetate (0.54 g, 2.4 mmol) and triethylamine (1.5 mL) were dissolved in anhydrous THF (40 mL) and ventilated three times under vacuum. The reaction system was heated to 75 ° C and stirred for 8 hours. After the reaction was cooled to room temperature, the solvent was removed under reduced pressure and separated and purified by silica gel column chromatography (petroleum ether / ethyl acetate = 1:2) to obtain B50, a white solid of 7.85 g, with a yield of 54%. Elemental analysis structure (C 73 H 78 N3O 15 P7): theoretical value C, 60.29; H, 5.41; N, 2.89; P, 14.91; test value C, 60.83; H, 5.21; N, 3.01; P, 15.09; MALDI-TOF mass spectrum: theoretical value 1454.3.4; experimental value 1454.3 (M + ).

[0101] Embodiment 14

[0102]

[0103] The preparation conditions and feed ratio of compound B51 are consistent with those of compound B50. It is only necessary to replace the reactant (6-(4-(diphenylphosphoryl)phenyl)-1,3,5-triazine-2,4-diyl)bis(4,1-phenylene))bis(bis(4-bromophenyl)phosphine oxide) with ((2-(4-(diphenylphosphoryl)phenyl)pyrimidine-4,6-diyl)bis(4,1-phenylene)bis(4-bromophenyl)phosphine oxide). The product is a white solid with a yield of 57%. Elemental analysis structure (C 74 H 79 N2O 15 P7): Theoretical value: C, 61.16; H, 5.48; N, 1.93; P, 14.92 Test value C, 60.83; H, 5.55; N, 1.97; P, 15.24; MALDI-TOF mass spectrum: Theoretical value 1453.3; Expected value 1453.3 (M + ).

[0104] Embodiment 15

[0105]

[0106] The preparation conditions and feed ratio of compound B52 are consistent with those of compound B50. It is only necessary to replace the reactant (6-(4-(diphenylphosphoryl)phenyl)-1,3,5-triazine-2,4-diyl)bis(4,1-phenylene))bis(bis(4-bromophenyl)phosphine oxide) with ((6-(4'-(diphenylphosphoryl)-[1,1'-biphenyl]-4-yl)-1,3,5-triazine-2,4-diyl)bis([1,1'-biphenyl]-4'-, 4-yl))bis(bis(4-bromophenyl)phosphine oxide). The product is a white solid with a yield of 58%. Elemental analysis structure (C 91 H 90 N3O 15 P7): Theoretical value: C, 64.96; H, 5.39; N, 2.50; P, 12.89 Test value C, 64.83; H, 5.55; N, 2.37; P, 13.24; MALDI-TOF mass spectrum: Theoretical value 1681.5; Expected value 1681.5 (M + ).

[0107] Example 16

[0108]

[0109] The preparation conditions and feed ratio of compound B53 are consistent with those of compound B48. It is only necessary to replace the reactant ((1,3,5-triazine-2,4,6-triyl)tris(phenyl-4,1-diyl))tris(bis(4-bromophenyl)phosphine oxide) with (1,3,5-triazine-2,4,6-triyl)tris([1,1'-biphenyl]-4',4-diyl))tris(bis(4-bromophenyl)phosphine oxide). The product is a white solid with a yield of 51%. Elemental analysis structure (:C 99 H 108 N3O 21 P9): Theoretical value: C, 60.83; H, 5.57; N, 2.15; O, 17.19; P, 14.26; Test value C, 61.14; H, 5.45; N, 2.61; P, 14.94; MALDI-TOF mass spectrum: Theoretical value 1953.5; Expected value 1953.5 (M + ).

[0110] Embodiment 17

[0111]

[0112] The preparation conditions and feed ratio of compound B54 are consistent with those of compound B50. It is only necessary to replace the reactant (6-(4-(diphenylphosphoryl)phenyl)-1,3,5-triazine-2,4-diyl)bis(4,1-phenylene))bis(bis(4-bromophenyl)phosphine oxide) with ((2-(4'-(diphenylphosphoryl)-[1,1'-biphenyl]-4-yl)pyrimidine-4,6-diyl)bis([1,1'-biphenyl]-4'-, 4-diyl))bis(bis(4-bromophenyl)phosphine oxide). The product is a white solid with a yield of 61%. Elemental analysis structure (C 91 H 88 N2O 15 P7): Theoretical value: C, 65.59; H, 5.32; N, 1.68; P, 13.01; Test value C, 65.83; H, 5.55; N, 1.74; P, 13.24; MALDI-TOF mass spectrum: Theoretical value 1666.4; Expected value 1666.4 (M + ).

[0113] Embodiment 18

[0114]

[0115] The preparation conditions and feed ratio of compound B55 are consistent with those of compound B48. It is only necessary to replace the reactant ((1,3,5-triazine-2,4,6-triyl)tris(benzene-4,1-diyl))tris(bis(4-bromophenyl)phosphine oxide) with pyrimidine-2,4,6-triyltris([1,1'-biphenyl]-4',4-diyl))tris(bis(4-bromophenyl)phosphine oxide). The product is a white solid with a yield of 53%. Elemental analysis structure (:C 100 H 109 N2O 21 P9): Theoretical value: C, 61.48; H, 5.62; N, 1.43; P, 14.27; Test value C, 61.14; H, 5.45; N, 1.51; P, 14.64; MALDI-TOF mass spectrum: Theoretical value 1952.5; Expected value 1952.5 (M + ).

[0116] Embodiment 19

[0117]

[0118] The preparation conditions and feed ratio of compound B64 are consistent with those of compound B48. It is only necessary to replace the reactant ((1,3,5-triazine-2,4,6-triyl)tris(benzene-4,1-diyl))tris(bis(4-bromophenyl)phosphine oxide) with 2,4,6-tris(4-(2,7-dibromo-9,9-dimethylacridin-10(9H)-yl)phenyl)-1,3,5-triazine. The product is a yellow solid with a yield of 49%. Elemental analysis structure (C 90 H 108 N6O 18 P6): Theoretical value: C, 61.85; H, 6.23; N, 4.81; P, 10.63; Test value C, 62.14; H, 6.45; N, 4.57; P, 10.97; MALDI-TOF mass spectrum: Theoretical value 1946.6; Expected value 1746.6 (M + ).

[0119] Embodiment 20

[0120]

[0121] The preparation conditions and feed ratio of compound B65 are consistent with those of compound B48. It is only necessary to replace the reactant ((1,3,5-triazine-2,4,6-triyl)tris(benzene-4,1-diyl))tris(bis(4-bromophenyl)phosphine oxide) with 2,4,6-tris(4-(2,7-dibromo-9,9-dimethylacridin-10(9H)-yl)phenyl)-1,3,5-triazine. The product is a yellow solid with a yield of 49%. Elemental analysis structure (C 90 H 108 N6O 18 P6): Theoretical value: C, 61.85; H, 6.23; N, 4.81; P, 10.63; Test value C, 62.14; H, 6.45; N, 4.57; P, 10.97; MALDI-TOF mass spectrum: Theoretical value 1946.6; Expected value 1746.6 (M + ).

[0122] Embodiment 21

[0123]

[0124] The preparation conditions and feed ratio of compound B66 are consistent with those of compound B50. It is only necessary to replace the reactant (6-(4-(diphenylphosphoryl)phenyl)-1,3,5-triazine-2,4-diyl)bis(4,1-phenylene))bis(bis(4-bromophenyl)phosphine oxide) with 10,10'-(6-(4-(9,9-dimethylacridin-10(9H)-yl)phenyl)-1,3,5-triazine-2,4-diyl)bis(4,1-phenylene))bis(2,7-dibromo-9,9-dimethyl-9,10-dihydroacridine). The product is a light yellow solid with a yield of 66%. Elemental analysis structure (C 81 H 88 N6O 12 P4): Theoretical value: C, 66.57; H, 6.07; N, 5.75; P, 8.48; Test value C, 65.93; H, 5.95; N, 5.74; P, 8.94; MALDI-TOF mass spectrum: Theoretical value 1460.5; Expected value 1460.5 (M + ).

[0125] Embodiment 22

[0126]

[0127] The preparation conditions and feed ratio of compound B67 are consistent with those of compound B50. It is only necessary to replace the reactant (6-(4-(diphenylphosphoryl)phenyl)-1,3,5-triazine-2,4-diyl)bis(4,1-phenylene))bis(bis(4-bromophenyl)phosphine oxide) with 10,10'-((2-(4-(9,9-dimethylacridine-10(9H)-yl)phenyl)pyrimidine-4,6-diyl)bis(4,1-phenylene))bis(2,7-dibromo-9,9-dimethyl-9,10-dihydroacridine). The product is a light yellow solid with a yield of 63%. Elemental analysis structure (C 82 H 89 N5O 12 P4): Theoretical value: C, 67.43; H, 6.14; N, 4.80; P, 8.48; Test value C, 66.98; H, 5.97; N, 4.74; P, 8.64; MALDI-TOF mass spectrum: Theoretical value 1459.5; Expected value 1459.5 (M + ).

[0128] Embodiment 23

[0129]

[0130] The preparation conditions and feed ratio of compound B94 are the same as those of compound B4, except that the reactant diethyl phosphite is replaced by diethyl trithiophosphite. The product is a white solid with a yield of 73%. Elemental analysis structure (C33 H 42 N3P3S9): theoretical value C, 45.97; H, 4.91; N, 4.87; P, 10.78; S, 33.47; measured value C, 46.24; H, 5.07; N, 4.63; P, 11.78; S, 32.98; MALDI-TOF mass spectrum: theoretical value 861.0; experimental value 861.0 (M + ).

[0131] Embodiment 24

[0132]

[0133] The preparation conditions and feed ratio of compound B98 are the same as those of compound B48, except that the reactant diethyl phosphite is replaced by diethyl trithiophosphite. The product is a white solid with a yield of 69%. Elemental analysis structure (C 33 H 42 N3P3S9): theoretical value C, 48.27; H, 4.80; N, 2.08; P, 13.83; S, 28.63; measured value C, 48.62; H, 4.56; N, 1.98; P, 14.03; S, 28.47; MALDI-TOF mass spectrum: theoretical value 2013.0; experimental value 2014.0 (M + ).

[0134] Embodiment 25

[0135]

[0136] The preparation conditions and feed ratio of compound B103 are the same as those of compound B64, except that the reactant diethyl phosphite is replaced by diethyl trithiophosphite. The product is a white solid with a yield of 57%. Elemental analysis structure (C 90 H 108 N6P6S 18 ): theoretical value C, 53.07; H, 5.34; N, 4.13; P, 9.12; S, 28.33; measured value C, 59.86; H, 5.47; N, 3.99; P, 9.25; S, 28.62; MALDI-TOF mass spectrum: theoretical value 2034.2; experimental value 2034.2 (M + ).

[0137] Device Example:

[0138] (I) The compounds of the present invention as additives

[0139] 1. Preparation of perovskite precursor solution

[0140] Lead bromide (PbBr2), methylamine chloride (MACl), methylammonium bromide (FABr), and phenylammonium bromide (PEABr) were dissolved in a mixed solvent of dimethyl sulfoxide (DMSO) and N-dimethylformamide (DMF) (volume ratio was 1:1) according to a molar ratio of 5:0.5:4:2. 2+ The molar concentration was 0.2 mol / L. The solution was stirred for 10 hours, allowed to stand, and filtered before use.

[0141] 2. Preparation of perovskite light-emitting devices

[0142]

[0143] The specific device structure (device structure 1) adopted is ITO / PEDOT:PSS / PVK / EML (~50nm) / TPBi / LiF / Al, wherein ITO, PEDOT:PSS, PVK, TPBi, LiF, and Al are anode, hole injection layer, hole transport layer, electron transport layer, electron injection layer, and cathode, respectively.

[0144] The device manufacturing process is as follows: a layer of PEDOT:PSS is spin-coated on indium tin oxide supported on a glass substrate, and annealed at 100°C for 15 minutes in air. Then, it is transferred to a nitrogen atmosphere, and polyvinyl carbazole (PVK) dissolved in chlorobenzene solvent with a mass concentration of 10 mg / mL is spin-coated on PEDOT:PSS, annealed at 120°C for 30 minutes, and then the perovskite light-emitting layer is spin-coated at a speed of 8000 rpm. At the 10th second of the spin coating of the above perovskite precursor solution, an ethyl acetate solution containing a phosphate compound with 1,3,5-triazine or pyrimidine as the core of the present invention is added dropwise, annealed at 80°C for 30 minutes, and then transferred to a 5×10 -4 Pa, 1,3,5-tri(1-phenyl-1H-benzimidazol-2-yl)benzene (TPBi), lithium fluoride (LiF), and aluminum (Al) cathode are deposited in sequence to obtain a perovskite electroluminescent device.

[0145] Embodiment 26

[0146] Formula B1 in Example 1 was used as an implementation object, and Formula B1 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the obtained device was tested. The test results are shown in Table 1.

[0147] Embodiment 27

[0148] Formula B2 in Example 2 was used as an implementation object, and Formula B2 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0149] Embodiment 28

[0150] Formula B3 in Example 3 was used as an implementation object, and Formula B3 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0151] Embodiment 29

[0152] Formula B4 in Example 4 was used as an implementation object, and Formula B4 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0153] Embodiment 30

[0154] Formula B5 in Example 5 was used as an implementation object, and Formula B5 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the obtained device was tested. The test results are shown in Table 1.

[0155] Embodiment 31

[0156] Formula B6 in Example 6 was used as an implementation object, and Formula B6 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0157] Embodiment 32

[0158] Formula B44 in Example 7 was used as an implementation object, and Formula B44 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0159] Embodiment 33

[0160] Formula B45 in Example 8 was used as an implementation object, and Formula B45 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0161] Embodiment 34

[0162] Formula B46 in Example 9 was used as an implementation object, and Formula B46 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0163] Embodiment 35

[0164] Formula B47 in Example 10 was used as an implementation object, and Formula B47 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0165] Embodiment 36

[0166] Formula B48 in Example 11 was used as an implementation object, and Formula B48 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0167] Embodiment 37

[0168] Formula B49 in Example 12 was used as an implementation object, and Formula B49 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0169] Embodiment 38

[0170] Formula B50 in Example 13 was used as an implementation object, and Formula B50 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0171] Embodiment 39

[0172] Formula B52 in Example 15 was used as an implementation object, and Formula B52 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0173] Embodiment 40

[0174] Formula B53 in Example 16 was used as an implementation object, and Formula B53 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0175] Embodiment 41

[0176] Formula B55 in Example 18 was used as an implementation object, and Formula B55 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0177] Embodiment 42

[0178] Formula B64 in Example 19 was used as an implementation object, and Formula B64 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0179] Embodiment 43

[0180] Formula B65 in Example 20 was used as an implementation object, and Formula B65 was dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0181] Embodiment 44

[0182] Formula B4 in Example 4 was used as an implementation object, and Formula B4 was dissolved in ethyl acetate at a concentration of 1.6 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0183] Embodiment 45

[0184] Formula B4 in Example 4 was used as an implementation object, and Formula B4 was dissolved in ethyl acetate at a concentration of 2.4 mg / ml, and was added dropwise to the film surface as an antisolvent during the film formation process of the perovskite light-emitting layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the resulting device was tested. The test results are shown in Table 1.

[0185] Comparative Example 1

[0186] Ethyl acetate without additives was used as the implementation object, and ethyl acetate was added as an anti-solvent to the surface of the film during the film formation process of the perovskite light-emitting layer. The perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 1", and the obtained device was tested. The test results are shown in Table 1.

[0187] Comparative Example 2

[0188]

[0189] Dioctyl octylphosphonate (TOPO) without carrier transport function was used as the implementation object, dissolved in ethyl acetate at a concentration of 0.8 mg / ml, and added as an anti-solvent to the surface of the film during the film formation process of the perovskite light-emitting layer. The perovskite light-emitting device was prepared using the structure and process described in "Device Structure 1". The obtained device was tested. The test results are shown in Table 1.

[0190] Comparative Example 3

[0191] Dioctyl octylphosphonate, which does not have a carrier transport function, was used as the implementation object. It was dissolved in ethyl acetate at a concentration of 1.6 mg / ml and added dropwise to the surface of the film as an antisolvent during the film formation process of the perovskite light-emitting layer. The perovskite light-emitting device was prepared using the structure and process described in "Device Structure 1". The obtained device was tested. The test results are shown in Table 1.

[0192] Comparative Example 4

[0193] Dioctyl octylphosphonate, which does not have a carrier transport function, was used as the implementation object. It was dissolved in ethyl acetate at a concentration of 2.4 mg / mL and added dropwise to the surface of the film as an antisolvent during the film formation process of the perovskite light-emitting layer. The perovskite light-emitting device was prepared using the structure and process described in "Device Structure 1". The obtained device was tested. The test results are shown in Table 1.

[0194] The performance of the perovskite light-emitting devices prepared in Examples 26-45 of the present invention and Comparative Examples 1-4 was tested. The test results are shown in Table 1, wherein the fluorescence lifetime was obtained by testing the perovskite light-emitting layer prepared on a glass substrate; the fluorescence quantum efficiency was measured by an integrating sphere; the starting voltage was 1 cd / m 2 The device voltage at .

[0195] Table 1 Photophysical data of perovskite light-emitting layers prepared in Examples 26-45 and Comparative Examples 1-4 and device performance of light-emitting devices

[0196]

[0197]

[0198] It can be seen from the data in Table 1 that compared with comparative example 1 without additives, the perovskite light-emitting layer provided by the present invention containing a phosphate compound with 1,3,5-triazine or pyrimidine as the core as an additive has a generally long fluorescence lifetime and a high fluorescence quantum efficiency. The perovskite light-emitting device prepared based on the above-mentioned light-emitting layer has a better external quantum efficiency, indicating that the compound provided by the present invention can passivate the surface defects of the perovskite light-emitting layer film, and finally achieve an external quantum efficiency of 27.1%. Compared with the perovskite light-emitting device based on the additive (TOPO) without carrier transport effect (Comparative Examples 2-4), the starting voltage of the perovskite light-emitting device (Example 29, Example 44-45) based on the compound provided by the present invention is mostly additives. It is not dependent on the concentration of the additive, indicating that the compound provided by the present invention has carrier transport properties. In summary, the compound provided by the present invention has both carrier transport and passivation perovskite defect effects, two synergistic effects, and finally achieves the performance improvement of the perovskite light-emitting device.

[0199] (II) Compounds prepared by the present invention as electron transport materials

[0200] 1. Preparation of perovskite precursor solution

[0201] Lead bromide (PbBr2), methylamine chloride (MACl), methylammonium bromide (FABr), and phenylammonium bromide (PEABr) were dissolved in a mixed solvent of dimethyl sulfoxide (DMSO) and N-dimethylformamide (DMF) (volume ratio was 1:1) according to a molar ratio of 5:0.5:4:2. 2+The molar concentration was 0.2 mol / L. The solution was stirred for 10 hours, allowed to stand, and filtered before use.

[0202] 2. Preparation of perovskite light-emitting devices

[0203]

[0204] The specific device structure (device structure 2) adopted is ITO / PEDOT:PSS / PVK / EML (~50nm) / ETL / LiF / Al, wherein ITO, PEDOT:PSS, PVK, LiF, and Al are anode, hole injection layer, hole transport layer, electron injection layer, and cathode, respectively, and the compound serves as electron transport layer (ETL).

[0205] The device manufacturing process is as follows: a layer of PEDOT:PSS is spin-coated on the indium tin oxide supported on the glass substrate, and annealed at 100°C for 15 minutes in air. Then, it is transferred to a nitrogen atmosphere, and polyvinyl carbazole (PVK) dissolved in chlorobenzene solvent with a mass concentration of 10 mg / mL is spin-coated on the PEDOT:PSS, annealed at 120°C for 30 minutes, and then the perovskite light-emitting layer is spin-coated at a speed of 8000 rpm, and then transferred to a 5×10 -4 Under a vacuum degree of 1.5 Pa, the compound of the present invention is sequentially deposited as an electron transport layer, lithium fluoride (LiF), and an aluminum (Al) cathode to obtain a perovskite electroluminescent device.

[0206] Embodiment 46

[0207] Formula B2 in Example 2 was used as an implementation object, and the compound represented by Formula B2 was prepared on the perovskite light-emitting layer by an evaporation process as an electron transport layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 2", and the obtained device was tested. The test results are shown in Table 2.

[0208] Embodiment 47

[0209] Formula B3 in Example 3 was used as an implementation object, and the compound represented by Formula B3 was prepared on the perovskite light-emitting layer by an evaporation process as an electron transport layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 2", and the obtained device was tested. The test results are shown in Table 2.

[0210] Embodiment 48

[0211] Formula B4 in Example 4 was used as an implementation object, and the compound represented by Formula B4 was prepared on the perovskite light-emitting layer by an evaporation process as an electron transport layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 2", and the obtained device was tested. The test results are shown in Table 2.

[0212] Embodiment 49

[0213] Formula B6 in Example 6 was used as an implementation object, and the compound represented by Formula B6 was prepared on the perovskite light-emitting layer by an evaporation process as an electron transport layer. A perovskite electroluminescent device was prepared using the structure and process described in "Device Structure 2", and the obtained device was tested. The test results are shown in Table 2.

[0214] Comparative Example 5

[0215]

[0216] A compound without a phosphate group (2,4,6-triphenyl-1,3,5-triazine, TRZ) was used as an implementation object and was prepared on the perovskite light-emitting layer as an electron transport layer by an evaporation process. A perovskite light-emitting device was prepared using the structure and process described in "Device Structure 2". The obtained device was tested. The test results are shown in Table 2.

[0217] The performance of the perovskite light-emitting devices prepared in Examples 46-49 of the present invention and Comparative Example 5 was tested, and the test results are shown in Table 2. The fluorescence lifetime was obtained by sequentially preparing the perovskite light-emitting layer on the glass substrate and the compound as the electron transport layer as the test sample; the fluorescence quantum efficiency was measured by the above sample using an integrating sphere; the starting voltage was 1 cd / m 2 The device voltage at .

[0218] Table 2 Photophysical data of perovskite light-emitting layers prepared in Examples 46-49 and Comparative Example 5 and device performance of light-emitting devices

[0219]

[0220] It can be seen from the data in Table 2 that compared with the perovskite light-emitting layer based on the triazine unit without phosphate group (Comparative Example 5) as the electron transport layer, the perovskite light-emitting sample provided by the present invention containing a phosphate compound with 1,3,5-triazine or pyrimidine as the core as the electron transport layer has a generally long fluorescence lifetime and high fluorescence quantum efficiency. The electron transport layer perovskite light-emitting device prepared based on the above compound has a high external quantum efficiency, indicating that the compound provided by the present invention can passivate the interface defects between the perovskite light-emitting layer and the electron transport layer, and ultimately achieve an external quantum efficiency of 26.1%.

[0221] The above embodiments are only used to help understand the method and core idea of ​​the present invention. It should be noted that, for those skilled in the art, several improvements and modifications can be made to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A phosphate compound with 1,3,5-triazine or pyrimidine as the core, characterized in that: The compound has a structure shown in formula (I): Wherein, n is selected from an integer of 0-2, m is selected from an integer of 1-3, and the sum of n and m is 3; k represents The number of phosphate groups on the above; X1 is selected from C atoms or N atoms; Y1, Y2, Y3 are each independently selected from O or S atoms; and Each is independently selected from a substituted or unsubstituted C6-C60 aromatic ring group, a substituted or unsubstituted C5-C60 aromatic heterocyclic group; R1 and R2 are each independently selected from a substituted or unsubstituted C1-C30 straight-chain hydrocarbon group, a substituted or unsubstituted C3-C30 branched hydrocarbon group, a substituted or unsubstituted C3-C30 cyclic hydrocarbon group, a substituted or unsubstituted C1-C30 halogenated hydrocarbon group, a substituted or unsubstituted C6-C60 aromatic group, a substituted or unsubstituted C5-C60 aromatic heterocyclic group; non-adjacent carbon atoms of the straight-chain hydrocarbon group, branched hydrocarbon group, cyclic hydrocarbon group, and halogenated hydrocarbon group can also be substituted by O, S, Si or -CO-O-; the dotted lines between the groups indicate that the groups can be bonded at any position.

2. The phosphate compound with 1,3,5-triazine or pyrimidine as the core according to claim 1, characterized in that: The heteroatoms in the aromatic heterocyclic group are selected from one or more of Si, Ge, S, O, Se, N and P.

3. The phosphate compound with 1,3,5-triazine or pyrimidine as the core according to claim 1, characterized in that: The substituents in the substituted C6-C60 aromatic ring group or the substituted C5-C60 heteroaromatic group are selected from H, D, F, Cl, Br, I, -CN, -NO2, -OR 1 、-SR 1 , -Se-R 1 , -Te-R 1 , A C1-C30 straight chain hydrocarbon group, a C3-C30 branched hydrocarbon group, a C3-C30 cyclic hydrocarbon group, a C6-C60 aromatic group, or a C5-C60 heteroaromatic group; Among them, the R 1 , R 2 and R 3 Each occurrence is the same or different and is independently selected from the following groups: (i) H, halogen, -CN, -NO2, OH, C1-C30 straight chain hydrocarbon group, C3-C30 branched hydrocarbon group, C3-C30 cyclic hydrocarbon group, C1-C30 halogenated hydrocarbon group, C1-C30 alkoxy chain; one or more non-adjacent carbon atoms in the straight chain, branched chain or cyclic hydrocarbon group, halogenated hydrocarbon group, alkoxy chain may be substituted by O, S, Si, -CO-O-; (ii) substituted or unsubstituted C6-C60 aromatic ring group, substituted or unsubstituted C5-C60 heteroaromatic ring group; R 1 , R 2 and R 3 They can also be connected by chemical bonds to form a bridge structure.

4. The phosphate compound with 1,3,5-triazine or pyrimidine as the core according to claim 1, characterized in that: and Each independently selected from the following groups: Wherein, L1, L2 and L3 are the same or different each time they appear, and are independently selected from the following groups: (i) H, halogen, -CN, -NO2, -OH, C1-C30 straight chain hydrocarbon group, C3-C30 branched hydrocarbon group, C3-C30 cyclic hydrocarbon group, C1-C30 halogenated hydrocarbon group, C1-C30 alkoxy chain; one or more non-adjacent carbon atoms in the straight chain, branched or cyclic hydrocarbon group, halogenated hydrocarbon group, alkoxy chain can be substituted by O, S, Si, -CO-O-; (ii) substituted or unsubstituted C6-C60 aromatic ring group, substituted or unsubstituted C5-C60 heteroaromatic ring group; L1, L2 and L3 can also be connected by chemical bonds to form a bridge structure.

5. The phosphate compound with 1,3,5-triazine or pyrimidine as the core according to claim 4, characterized in that: and Independently selected from the following structures:

6. The phosphate compound with 1,3,5-triazine or pyrimidine as the core according to claim 1, characterized in that: It has one of the structures shown in formula B1 to B105:

7. A method for preparing a phosphate ester compound with 1,3,5-triazine or pyrimidine as the core according to any one of claims 1 to 6, characterized in that: The specific steps include: The target compound (I) is prepared by a Pd-catalyzed phosphorylation reaction of an aromatic halide (Formula (II)) with 1,3,5-triazine or pyrimidine as the molecular core and a phosphate (Formula (III)); Wherein, Lu is a halogen, preferably Br or I, and k is The number of halogens on the surface; The definitions of X1, n, and m are consistent with those of the compound formula (I) in claims 1-5; Wherein, the definitions of R1, R2, Y1, Y2 and Y3 are consistent with those in the compound formula (I) in claims 1-5.

8. The method for preparing a phosphate ester compound with 1,3,5-triazine or pyrimidine as the core according to claim 7, characterized in that: The reaction temperature of the Pd-catalyzed phosphorylation reaction is 50-68° C., the catalytic system is palladium acetate / dppf / potassium acetate / triethylamine / THF or Pd(PPh3)4 / N-methylmorpholine / toluene, and the reaction time is 1.5 to 12 hours.

9. Use of the phosphate compound with 1,3,5-triazine or pyrimidine as the core as claimed in any one of claims 1 to 6 as a perovskite light-emitting layer additive or electron transport material in a perovskite light-emitting device.

10. A perovskite light-emitting device, characterized in that: At least one of the perovskite light-emitting layer or the electron transport layer in the perovskite light-emitting device contains the phosphate compound with 1,3,5-triazine or pyrimidine as the core as described in any one of claims 1 to 6.

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