Platinum complex luminescent materials and their applications

Abstract

The present invention relates to platinum complex luminescent materials and their applications. The platinum complex is a compound having the structure of chemical formula (I). When used in organic light-emitting diodes, the compound has a low driving voltage and high luminous efficiency, and can significantly increase the service life of the device, showing potential for application in the field of organic electroluminescent devices. The present invention also provides an organic electrophotoelectric device comprising a cathode, an anode, and an organic layer, wherein the organic layer is one or more of a hole injection layer, a hole transport layer, a light-emitting layer, a hole blocking layer, an electron transport layer, and an electron injection layer, and at least one of the organic layers contains the compound of structural formula (I).

Description

Technical Field

[0001] The present invention relates to the field of luminescent materials, and in particular to a platinum complex containing an NNCN tetradentate ligand and an application thereof in an organic light-emitting diode. Background Art

[0002] Organic optoelectronic devices include, but are not limited to, the following categories: organic light-emitting diodes (OLEDs), organic thin-film transistors (OTFTs), organic photovoltaics (OPVs), light-emitting electrochemical cells (LCEs), and chemical sensors.

[0003] In recent years, organic light-emitting diodes (OLEDs), a promising lighting and display technology, have garnered widespread attention from both academia and industry. Their self-luminescence, wide viewing angle, fast response time, and the ability to produce flexible devices have made them a strong contender for next-generation display and lighting technologies. However, OLEDs still face challenges such as low efficiency and short lifespan, requiring further research.

[0004] Early fluorescent OLEDs typically only utilized singlet excitons for emission. The triplet excitons generated in the device could not be effectively utilized and returned to the ground state non-radiatively, limiting their widespread use. In 1998, Zhi Zhiming et al. from the University of Hong Kong first reported the phenomenon of electrophosphorescence. That same year, Thompson et al. fabricated phosphorescent OLEDs using transition metal complexes as luminescent materials. Phosphorescent OLEDs efficiently utilize both singlet and triplet excitons for emission, theoretically achieving 100% internal quantum efficiency, significantly accelerating the commercialization of OLEDs. The color of OLED emission can be manipulated through structural design of the luminescent material. OLEDs can include one or more luminescent layers to achieve the desired spectrum. Currently, green, yellow, and red phosphorescent materials have been commercialized. Commercial OLED displays typically utilize a combination of blue fluorescence and yellow, or green and red phosphorescence, to achieve full-color displays. However, the industry urgently needs luminescent materials with higher efficiency and longer lifespans. Metal complex luminescent materials have been used in industry, but their performance, such as luminous efficiency and lifespan, still needs to be further improved. Summary of the Invention

[0005] In view of the above problems existing in the prior art, the present invention provides a type of platinum complex luminescent material containing an NNCN tetradentate ligand, which has good luminous efficiency when applied to organic light-emitting diodes.

[0006] The present invention also provides an organic light-emitting diode containing the platinum complex.

[0007] The platinum complex containing the NNCN tetradentate ligand is a compound having the structure of formula (I):

[0008]

[0009] in:

[0010] X1 to X 17 are each independently selected from N or CR;

[0011] A is selected from CR 1 R 2 ,NR 3 ,O,S or Se;

[0012] R, R 1 , R 2 , R 3 Each is independently selected from the following groups: hydrogen, deuterium, halogen, amino, carbonyl, carboxyl, sulfanyl, cyano, sulfonyl, phosphino, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, and combinations thereof; or two adjacent substituents can be optionally linked to form a ring;

[0013] The heteroatoms in the heteroaryl group are one or more of N, S, and O;

[0014] The substitution is substitution by halogen, amino, cyano or C1-C4 alkyl.

[0015] Preferably, R, R 1 , R 2 , R 3 Each is independently selected from the group consisting of hydrogen, deuterium, halogen, amino, sulfanyl, cyano, substituted or unsubstituted alkyl having 1 to 6 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 6 ring carbon atoms, substituted or unsubstituted alkenyl having 2 to 6 carbon atoms, substituted or unsubstituted alkoxy having 1 to 6 carbon atoms, substituted or unsubstituted aryl having 6 to 12 carbon atoms, and substituted or unsubstituted heteroaryl having 3 to 6 carbon atoms.

[0016] Preferably, R, R 1 , R 2 , R 3 Each is independently selected from the group consisting of hydrogen, deuterium, halogen, C1-C4 alkyl, cyano, substituted or unsubstituted cycloalkyl having 3-6 ring carbon atoms, substituted or unsubstituted aryl having 6-12 carbon atoms, and substituted or unsubstituted heteroaryl having 3-6 carbon atoms.

[0017] Preferably, R, R1 , R 2 , R 3 Each is independently selected from the group consisting of hydrogen, deuterium, methyl, isopropyl, isobutyl, tert-butyl, cyano, substituted or unsubstituted cyclopentyl, substituted or unsubstituted cyclohexyl, substituted or unsubstituted phenyl, substituted or unsubstituted pyridyl, substituted or unsubstituted pyrazinyl, and substituted or unsubstituted pyrimidinyl.

[0018] Preferably, the general formula (I) is the following structure:

[0019]

[0020] R, R 1 , R 2 Each is independently selected from the group consisting of hydrogen, deuterium, methyl, tert-butyl, substituted or unsubstituted cyclopentyl, substituted or unsubstituted cyclohexyl, substituted or unsubstituted phenyl, and substituted or unsubstituted pyridyl.

[0021] More preferably, the general formula (I) is the following structure:

[0022]

[0023] R is selected from the group consisting of hydrogen, deuterium, methyl, tert-butyl, substituted or unsubstituted cyclopentyl, substituted or unsubstituted cyclohexyl, substituted or unsubstituted phenyl, and substituted or unsubstituted pyridyl.

[0024] Preferred: X1 to X 17 Each is independently selected from CR.

[0025] Among them, X1-X3, X 14 To X 17 For CH.

[0026] Preferably: at least one CR in X4-X6 is not CH; at least one CR in X7-X9 is not CH, X 10 -X 13 At least one CR is not CH.

[0027] In X4-X6, X5 is not CH, and in X7-X9, X8 is not CH, X 10 -X 13 Medium X 11 Not CH, the rest are CH.

[0028] Preferably: at least one CR in X4-X6 is not CH; X7-X9 is CH, X 10 -X 13 At least one CR is not CH.

[0029] In X4-X6, X5 is not CH, X 10 -X13 Medium X 11 Not CH, the rest are CH.

[0030] The following are examples of platinum metal complexes according to the present invention, but are not limited to the structures listed:

[0031]

[0032]

[0033]

[0034]

[0035] The precursor of the above metal complex, i.e. the ligand, has the following structural formula:

[0036]

[0037] Where X1 to X 17 , A is defined as above.

[0038] The present invention also provides a use of the above-mentioned platinum complex in an organic optoelectronic device, which includes, but is not limited to, an organic light emitting diode, an organic thin film transistor, an organic photovoltaic device, a light emitting electrochemical cell and a chemical sensor, preferably an organic light emitting diode.

[0039] An organic light emitting diode comprising the platinum complex, wherein the platinum complex is a luminescent material in a light emitting device.

[0040] The organic light-emitting diode of the present invention comprises a cathode, an anode and an organic layer, wherein the organic layer is one or more layers selected from the group consisting of a hole injection layer, a hole transport layer, a light-emitting layer, a hole blocking layer, an electron injection layer and an electron transport layer, and not all of these organic layers need to be present; at least one of the hole injection layer, the hole transport layer, the hole blocking layer, the electron injection layer, the light-emitting layer and the electron transport layer contains the platinum complex described in formula (I).

[0041] Preferably, the layer where the platinum complex of formula (I) is located is a light-emitting layer or an electron transport layer.

[0042] The total thickness of the organic layer of the device of the present invention is 1-1000 nm, preferably 1-500 nm, more preferably 5-300 nm.

[0043] The organic layer can be formed into a thin film by evaporation or solution method.

[0044] The series of platinum complex luminescent materials disclosed in the present invention have good luminescence properties and can be used as luminescent materials in organic light-emitting diodes. They have low driving voltage and high luminescence efficiency, and can significantly improve the service life of the device. They have potential for application in the field of organic electroluminescent devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 is a structural diagram of an organic light emitting diode device according to the present invention,

[0046] Among them, 10 represents the glass substrate, 20 represents the anode, 30 represents the hole injection layer, 40 represents the hole transport layer, 50 represents the light emitting layer, 60 represents the electron transport layer, 70 represents the electron injection layer, and 80 represents the cathode. DETAILED DESCRIPTION

[0047] The present invention does not require the synthesis method of the materials. In order to describe the present invention in more detail, the following examples are given, but are not limited thereto. The raw materials used in the following synthesis are all commercially available products unless otherwise specified.

[0048] Example 1:

[0049] Synthesis of complex 13

[0050]

[0051] Synthesis of compound 13b:

[0052] Under nitrogen, m-phenylenediboronic acid (4.0 g, 24.1 mmol), 4-tert-butyl-2-chloropyridine (9.0 g, 53.0 mmol), tetrakistriphenylphosphine palladium (1.39 g, 1.21 mmol), potassium carbonate solution (2 M, 12 mL), and toluene (40 mL) were added to a three-necked flask. Vacuum and nitrogen flow were repeated three times. The reaction mixture was then heated to reflux and stirred overnight. After cooling to room temperature, the mixture was extracted with ethyl acetate. The organic phase was washed three times with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. The residue was separated by silica gel column chromatography to obtain 6.2 g of a light yellow oil in a 75% yield. ESI-MS (m / z): 345.23 (M+1).

[0053] Synthesis of compound 13c:

[0054] 13b (4.0 g, 11.6 mmol), 30% hydrogen peroxide (2 mL), and acetic acid (20 mL) were added to a flask. The mixture was stirred at room temperature for 30 minutes, then heated to 60°C and stirred for 6 hours. After cooling to room temperature, the mixture was extracted with ethyl acetate. The organic phase was washed three times with saturated sodium sulfite solution, dried over anhydrous sodium sulfate, and the solvent was removed under reduced pressure. The remaining crude product was dissolved in phosphorus oxychloride (10 mL) and heated to reflux with stirring for 4 hours. After most of the phosphorus oxychloride was removed under reduced pressure, the mixture was slowly added to saturated sodium carbonate solution. The mixture was extracted with dichloromethane, the organic phases were combined, dried over anhydrous sodium sulfate, and the solvent was removed under reduced pressure. The residue was separated by silica gel column chromatography to obtain 2.1 g of a light yellow solid in a 48% yield. ESI-MS (m / z): 379.19 (M+1).

[0055] Synthesis of compound 13e:

[0056] Under nitrogen protection, 13c (1.8 g, 4.8 mmol), 13d (synthesized with reference to patent KR20200109533A) (1.6 g, 4.8 mmol), tetrakistriphenylphosphine palladium (0.28 g, 0.24 mmol), potassium carbonate solution (2 M, 5 mL) and toluene (20 mL) were added to a three-necked flask. Vacuum and nitrogen were passed through, and the reaction mixture was repeated three times. Subsequently, the reaction mixture was heated to reflux and stirred overnight. After cooling to room temperature, the mixture was extracted with ethyl acetate. The organic phase was washed three times with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. The residue was separated by silica gel column chromatography to obtain 1.6 g of a light yellow solid with a yield of 61%. ESI-MS (m / z): 552.33 (M + 1).

[0057] Synthesis of complex 13:

[0058] In a 250 mL single-necked flask, 13e (0.90 g, 1.63 mmol), potassium chloroplatinate (0.81 g, 1.95 mmol), and tetrabutylammonium bromide (50 mg) were dissolved in acetic acid (150 mL). Under nitrogen, the reaction mixture was stirred at 135°C for 24 hours. After cooling to room temperature, water was added to the reaction solution to precipitate a solid, which was filtered to obtain the crude product. Recrystallization from dichloromethane / n-hexane (1 / 1) afforded 0.65 g of an orange-red powder in a 54% yield. ESI-HRMS (m / z): 745.2872 (M+1).

[0059] Example 2:

[0060] Synthesis of complex 33

[0061]

[0062] Synthesis of compound 33b

[0063] Under nitrogen protection, 13c (1.2 g, 3.17 mmol), 33a (synthesized with reference to patent KR20200109533A) (0.98 g, 3.17 mmol), tetrakistriphenylphosphine palladium (0.18 g, 0.16 mmol), potassium carbonate solution (2 M, 4 mL) and toluene (20 mL) were added to a three-necked flask. Vacuum and nitrogen were passed through, and the reaction mixture was repeated three times. Subsequently, the reaction mixture was heated to reflux and stirred overnight. After cooling to room temperature, the mixture was extracted with ethyl acetate. The organic phase was washed three times with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. The residue was separated by silica gel column chromatography to obtain 1.2 g of a light yellow solid with a yield of 72%. ESI-MS (m / z): 526.28 (M + 1).

[0064] Synthesis of complex 33

[0065] In a 250 mL single-necked flask, 33b (0.90 g, 1.71 mmol), potassium chloroplatinate (0.85 g, 2.05 mmol), and tetrabutylammonium bromide (50 mg) were dissolved in acetic acid (150 mL). Under nitrogen, the reaction mixture was stirred at 135°C for 24 hours. After cooling to room temperature, water was added to the reaction solution to precipitate a solid, which was then filtered to obtain the crude product. Recrystallization from dichloromethane / n-hexane (1 / 1) afforded 0.55 g of an orange-red powder in 45% yield. ESI-HRMS (m / z): 719.2355 (M+1).

[0066] Example 3:

[0067] Synthesis of complex 49

[0068]

[0069] Synthesis of compound 49b

[0070] Under nitrogen protection, 13c (1.20 g, 3.17 mmol), 49a (synthesized with reference to patent KR20200109533A) (1.24 g, 3.81 mmol), tetrakistriphenylphosphine palladium (0.18 g, 0.16 mmol), potassium carbonate solution (2 M, 4 mL) and toluene (20 mL) were added to a three-necked flask. Vacuum and nitrogen were passed through, and the reaction mixture was repeated three times. Subsequently, the reaction mixture was heated to reflux and stirred overnight. After cooling to room temperature, the mixture was extracted with ethyl acetate. The organic phase was washed three times with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. The residue was separated by silica gel column chromatography to obtain 1.1 g of a light yellow solid with a yield of 64%. ESI-MS (m / z): 542.26 (M + 1).

[0071] Synthesis of complex 49

[0072] In a 250 mL single-necked flask, 49b (0.95 g, 1.75 mmol), potassium chloroplatinate (0.87 g, 2.10 mmol), and tetrabutylammonium bromide (50 mg) were dissolved in acetic acid (150 mL). Under nitrogen, the reaction mixture was stirred at 135°C for 24 hours. After cooling to room temperature, water was added to the reaction solution to precipitate a solid, which was then filtered to obtain the crude product. Recrystallization from dichloromethane / n-hexane (1 / 1) afforded 0.60 g of an orange-red powder in 47% yield. ESI-HRMS (m / z): 735.2125 (M+1).

[0073] Example 4:

[0074] Synthesis of complex 61

[0075]

[0076] Synthesis of compound 61b

[0077] Under nitrogen protection, 13c (1.10 g, 2.90 mmol), 61a (synthesized with reference to patent KR20200109533A) (1.34 g, 3.49 mmol), tetrakistriphenylphosphine palladium (0.17 g, 0.15 mmol), potassium carbonate solution (2 M, 4 mL) and toluene (20 mL) were added to a three-necked flask. Vacuum and nitrogen were passed through, and the reaction mixture was repeated three times. Subsequently, the reaction mixture was heated to reflux and stirred overnight. After cooling to room temperature, the mixture was extracted with ethyl acetate. The organic phase was washed three times with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. The residue was separated by silica gel column chromatography to obtain 0.92 g of a light yellow solid with a yield of 53%. ESI-MS (m / z): 601.33 (M + 1).

[0078] Synthesis of complex 61

[0079] In a 250 mL single-necked flask, 61b (0.85 g, 1.41 mmol), potassium chloroplatinate (0.70 g, 1.69 mmol), and tetrabutylammonium bromide (50 mg) were dissolved in acetic acid (150 mL). Under nitrogen, the reaction mixture was stirred at 135°C for 24 hours. After cooling to room temperature, water was added to the reaction solution to precipitate a solid, which was then filtered to obtain the crude product. Recrystallization from dichloromethane / n-hexane (1 / 1) afforded 0.56 g of an orange-red powder in 50% yield. ESI-HRMS (m / z): 794.2826 (M+1).

[0080] Example 5:

[0081] Synthesis of complex 72

[0082]

[0083] Synthesis of compound 72b

[0084] Under nitrogen protection, 13c (1.10 g, 2.90 mmol), 72a (synthesized with reference to patent KR20200109533A) (1.60 g, 3.48 mmol), tetrakistriphenylphosphine palladium (0.17 g, 0.15 mmol), potassium carbonate solution (2 M, 4 mL) and toluene (20 mL) were added to a three-necked flask. Vacuum and nitrogen were passed through, and the reaction mixture was repeated three times. Subsequently, the reaction mixture was heated to reflux and stirred overnight. After cooling to room temperature, the mixture was extracted with ethyl acetate. The organic phase was washed three times with saturated brine, dried over anhydrous sodium sulfate, and the solvent was evaporated under reduced pressure. The residue was separated by silica gel column chromatography to obtain 0.82 g of a light yellow solid with a yield of 42%. ESI-MS (m / z): 676.37 (M + 1).

[0085] Synthesis of complex 72

[0086] In a 250 mL single-necked flask, 72b (0.70 g, 1.04 mmol), potassium chloroplatinate (0.52 g, 1.25 mmol), and tetrabutylammonium bromide (50 mg) were dissolved in acetic acid (100 mL). Under nitrogen, the reaction mixture was stirred at 135°C for 24 hours. After cooling to room temperature, water was added to the reaction solution to precipitate a solid, which was then filtered to obtain the crude product. Recrystallization from dichloromethane / n-hexane (1 / 1) afforded 0.39 g of an orange-red powder in 43% yield. ESI-HRMS (m / z): 869.3186 (M+1).

[0087] Those skilled in the art should be aware that the above preparation methods are only several illustrative examples, and those skilled in the art can obtain other compound structures of the present invention by improving them.

[0088] Example 6:

[0089] The organic light emitting diode is prepared by using the complex luminescent material of the present invention. The device structure is shown in FIG. Figure 1 .

[0090] First, the transparent conductive ITO glass substrate 10 (with the anode 20 thereon) is cleaned in sequence with a detergent solution and deionized water, ethanol, acetone, and deionized water, and then treated with oxygen plasma for 30 seconds.

[0091] Then, HATCN was vapor-deposited to a thickness of 10 nm on the ITO as the hole injection layer 30 .

[0092] Then, compound HT was evaporated to form a hole transport layer 40 with a thickness of 40 nm.

[0093] Then, a 20 nm thick light emitting layer 50 is evaporated on the hole transport layer. The light emitting layer is composed of a mixed doping of platinum complex 13 (20%) and CBP (80%).

[0094] Then, AlQ3 was evaporated to a thickness of 40 nm on the light-emitting layer as the electron transport layer 60 .

[0095] Finally, 1 nm LiF was evaporated to form the electron injection layer 70 and 100 nm Al was evaporated to form the device cathode 80 .

[0096] Example 7: Using complex 33 instead of complex 13, an organic light-emitting diode was prepared using the method described in Example 6. Example 8: Using complex 49 instead of complex 13, an organic light-emitting diode was prepared using the method described in Example 6. Example 9: Using complex 61 instead of complex 13, an organic light-emitting diode was prepared using the method described in Example 6. Example 10: Using complex 72 instead of complex 13, an organic light-emitting diode was prepared using the method described in Example 6.

[0097] Comparative Example 1:

[0098] Complex Ref-1 (US10566566B2) was used instead of complex 13, and an organic light-emitting diode was prepared using the method described in Example 6.

[0099] The structural formulas of HATCN, HT, AlQ3, Ref-1 and RH in the device are as follows:

[0100]

[0101]

[0102] The organic electroluminescent devices in Examples 6-10 and Comparative Example 1 were 2 The device performance at the current density is listed in Table 1:

[0103] Table 1

[0104]

[0105] As shown in Table 1, under the same conditions, the platinum complex material of the present invention can be used to prepare deep-red organic light-emitting diodes (OLEDs) with lower driving voltage and higher luminous efficiency. Furthermore, the device lifespan of OLEDs based on the complex of the present invention is significantly improved compared to the complex material in the comparative example, meeting the display industry's requirements for luminescent materials and demonstrating promising industrial prospects.

[0106] The above-described various embodiments are intended to be illustrative only and are not intended to limit the scope of the present invention. Without departing from the spirit of the present invention, the various materials and structures described herein may be replaced with other materials and structures. It should be understood that those skilled in the art can make numerous modifications and variations based on the principles of the present invention without requiring creative effort. Therefore, any technical solutions that can be derived from existing technologies through analysis, reasoning, or partial research should fall within the scope of protection defined by the claims.

Claims

1. A platinum complex containing a NNCN tetradentate ligand, which is a compound having the structure of formula (I): in: X1 to X 17 Each independently selected from CR; A is selected from CR 1 R 2 ,NR 3 , O, S or Se; R is independently selected from the group consisting of hydrogen, deuterium, halogen, cyano, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 6 ring carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 12 carbon atoms, or substituted or unsubstituted heteroaryl having 3 to 6 carbon atoms; R 1 , R 2 are each independently selected from the group consisting of hydrogen, deuterium, halogen, cyano, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 6 ring carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, or substituted or unsubstituted heteroaryl having 3 to 6 carbon atoms; R 3 independently selected from the group consisting of hydrogen, deuterium, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 6 ring carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, or substituted or unsubstituted heteroaryl having 3 to 6 carbon atoms; The heteroatoms in the heteroaryl group are one or more of N, S, and O; The substitution is substitution by halogen, cyano or C1-C4 alkyl.

2. The platinum complex according to claim 1, wherein R is independently selected from the group consisting of hydrogen, deuterium, halogen, cyano, substituted or unsubstituted alkyl having 1 to 6 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 6 ring carbon atoms, substituted or unsubstituted alkoxy having 1 to 6 carbon atoms, substituted or unsubstituted aryl having 6 to 12 carbon atoms, or substituted or unsubstituted heteroaryl having 3 to 6 carbon atoms; R 1 , R 2 each independently selected from hydrogen, deuterium, halogen, cyano, substituted or unsubstituted alkyl having 1 to 6 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 6 ring carbon atoms, substituted or unsubstituted alkoxy having 1 to 6 carbon atoms, substituted or unsubstituted aryl having 6 to 12 carbon atoms, or substituted or unsubstituted heteroaryl having 3 to 6 carbon atoms; R 3 independently selected from hydrogen, deuterium, substituted or unsubstituted alkyl having 1 to 6 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 6 ring carbon atoms, substituted or unsubstituted alkoxy having 1 to 6 carbon atoms, substituted or unsubstituted aryl having 6 to 12 carbon atoms, or substituted or unsubstituted heteroaryl having 3 to 6 carbon atoms; A is selected from CR 1 R 2 ,NR 3 , O or S.

3. The platinum complex according to claim 2, wherein the general formula (I) is the following structure: R, R 1 , R 2 Each is independently selected from hydrogen, deuterium, methyl, tert-butyl, substituted or unsubstituted cyclopentyl, substituted or unsubstituted cyclohexyl, substituted or unsubstituted phenyl or substituted or unsubstituted pyridyl.

4. The platinum complex according to any one of claims 1 to 3, wherein X1-X3, X 14 To X 17 For CH.

5. The platinum complex according to claim 4, wherein at least one CR among X4-X6 is not CH; at least one CR among X7-X9 is not CH, X 10 -X 13 At least one CR is not CH.

6. The platinum complex according to claim 5, wherein X5 in X4-X6 is not CH, and X8 in X7-X9 is not CH, X 10 -X 13 Medium X 11 Not CH, the rest are CH.

7. The platinum complex according to claim 4, wherein at least one CR among X4-X6 is not CH; X7-X9 is CH, X 10 -X 13 At least one CR is not CH.

8. The platinum complex according to claim 7, wherein X5 is not CH, X 10 -X 13 Medium X 11 Not CH, the rest are CH.

9. A platinum complex, which is one of the following compounds:

10. A precursor of a platinum complex, i.e., a ligand, having the following structural formula: Where X1 to X 17 , A is defined as described in any one of claims 1-9.

11. Use of the platinum complex according to any one of claims 1 to 9 in an organic light emitting diode, an organic thin film transistor, an organic photovoltaic device, a light emitting electrochemical cell or a chemical sensor.

12. An organic light-emitting diode comprising a cathode, an anode, and an organic layer, wherein the organic layer is one or more of a hole injection layer, a hole transport layer, a light-emitting layer, a hole blocking layer, an electron injection layer, and an electron transport layer, and the organic layer contains the platinum complex according to any one of claims 1 to 9. 13 . The organic light emitting diode according to claim 12 , wherein the layer where the platinum complex according to claim 1 is located is a light emitting layer.

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