CN106946941A - Organometallic complex and organic light emitting diode including the same - Google Patents

Abstract

The present disclosure provides an organometallic complex. The organometallic complex has the following chemical formula (I): Among them, one of R ₁ and R ₂ is trimethylsilyl, the other is hydrogen, at least one of R ₃ and R ₄ is fluorine or an alkyl group with 1 to 6 carbon atoms, or one of them is fluorine, and the other One is an alkyl group with 1 to 6 carbon atoms, for n=2 or 3, and m=0 or 1, where n+m=3. The present disclosure further provides an organic light-emitting diode including the above-mentioned organic metal complex.

Description

Organometallic complexes and organic light-emitting diodes containing them

【Technical field】

The present disclosure relates to an organometallic complex, in particular to an organometallic complex with excellent thermal stability and an organic light-emitting diode comprising the same.

【Background technique】

Organic Light Emitting Diode (OLED) has excellent characteristics such as thinness, self-luminescence, low power consumption, no need for backlight, no viewing angle limitation, and high response rate. Tomorrow's star. Nowadays, OLED elements are gradually using phosphorescent materials with higher luminous efficiency as dopant. Therefore, in addition to the need to match suitable host materials with comparable energy levels, the design of phosphorescent materials has also gradually received attention. Among them, blue phosphorescent luminescent materials need to have a large energy gap (E _g ), and qualified molecules must have a special ligand system. In addition, the thermal stability of phosphorescent luminescent materials must also be considered. .

FIrpic materials are often used in commercially available or academically published blue phosphorescent light-emitting materials for OLED elements. However, FIrpic materials are one of the reasons for the poor life of blue phosphorescent OLED elements. Therefore, it is necessary to develop phosphorescent materials that can replace FIrpic materials. Luminescent materials are a very important subject.

【Content of invention】

According to an embodiment of the present disclosure, it is an organic metal complex. This organometallic complex has a chemical structure shown in the following chemical formula (I):

In chemical _formula (I), _one of R1 and R2 is trimethylsilyl (trimethylsilyl), the other is hydrogen, and at least one of _R3 and R4 is fluorine or an alkyl group with ₁ to 6 carbons, or One of them is fluorine, and the other is an alkyl group with 1 to 6 carbons, for R can be CH ₃ , CH ₂ CH ₃ , CH(CH ₃ ) ₂ , C(CH ₃ ) ₃ , CF ₃ , CHF ₂ , C ₃ F ₈ or ph, n=2 or 3, and m=0 or 1 , where n+m=3.

According to another embodiment of the present disclosure, an organic light emitting diode (organic light emitting diode). The organic light-emitting diode comprises: a substrate; an anode, disposed on the substrate; a light-emitting layer, disposed on the anode, wherein the light-emitting layer comprises the above-mentioned organometallic complex with chemical formula (I); and a cathode, disposed on the anode on the luminescent layer.

In order to make the above-mentioned purpose, features and advantages of the present invention more comprehensible, a preferred embodiment will be described in detail below together with the accompanying drawings.

【Description of drawings】

1 is a schematic cross-sectional view of an organic light emitting diode according to an embodiment of the present disclosure; and

FIG. 2 is a schematic cross-sectional view of an organic light emitting diode according to an embodiment of the present disclosure.

【Symbol Description】

10, 100～organic light-emitting diodes;

12, 120 ~ substrate;

14, 140 ~ anode;

15, 150～hole transport layer;

16 ~ luminous layer;

17, 170～electron transport layer;

18, 180 ~ cathode;

160～the first light-emitting layer;

160'～the second light-emitting layer.

【detailed description】

According to an embodiment of the present disclosure, an organometallic complex has the following chemical formula (I):

In the chemical formula (I), R ₁ and R ₂ are each independent, and one of them is trimethylsilyl (trimethylsilyl, TMS), and the other is hydrogen, R ₃ and R ₄ are each independent, and at least one of them is fluorine or An alkyl group with 1 to 6 carbons, or one of them is fluorine and the other is an alkyl group with 1 to 6 carbons, Can be R can be _CH3 , _CH2CH3 , CH( _CH3 ) ₂ , C( _CH3 ) ₃ , _CF3 , _CHF2 , _C3F8 or ph, and n= ₂ or ₃ , and m=0 Or 1, and n+m=3.

In some embodiments, the organometallic complex of the present disclosure may have the following chemical formula (II):

Wherein R is fluorine or an alkyl group with ₁ to 6 carbons, for _R is _CH3 , _CH2CH3 , CH( _CH3 ) ₂ , C( _CH3 ) ₃ , _CF3 , _CHF2 , _C3F8 or _ph .

In some embodiments, the organometallic complexes of the present disclosure may include In the above chemical formula, Can be _R can be _CH3 , _CH2CH3 , CH( _CH3 ) ₂ , C( _CH3 ) ₃ , _CF3 , _CHF2 , _C3F8 , or _ph .

Table 1 below lists organometallic complexes of formula (I) obtained in a series of embodiments of the present disclosure, and their respective chemical structures are listed in the table below.

Table 1

According to an embodiment of the present disclosure, an organic light emitting diode (OLED) is provided. Please refer to FIG. 1 . FIG. 1 is a schematic cross-sectional view of an organic light emitting diode according to the present disclosure. The organic light emitting diode 10 includes a substrate 12, an anode 14, a hole transport layer (hole transport layer, HTL) 15, a light emitting layer 16, an electron transport layer (electron transport layer, ETL) 17 and a cathode 18, wherein the anode 14 is disposed on On the substrate 12 , the hole transport layer 15 is disposed on the anode 14 , the light emitting layer 16 is disposed on the hole transport layer 15 , the electron transport layer 17 is disposed on the light emitting layer 16 , and the cathode 18 is disposed on the electron transport layer 17 .

In some embodiments, the material of the substrate 12 may include glass, plastic or semiconductor.

In some embodiments, the material of the anode 14 may include indium tin oxide (ITO), indium zinc oxide (IZO), zinc aluminum oxide (AZO), zinc oxide (ZnO) or combinations thereof.

In some embodiments, the material of the hole transport layer (HTL) 15 and the electron transport layer (ETL) 17 may include

In some embodiments, the light emitting layer 16 may include a host material (host) and a dopant (dopant).

In some embodiments, the primary emitter material may include

In some embodiments, the dopant may include an organometallic complex having the following formula (I):

In the chemical formula (I), one of R ₁ and R ₂ is trimethylsilyl (trimethylsilyl, TMS), the other is hydrogen, and at least one of R ₃ and R ₄ is fluorine or an alkyl group with 1 to 6 carbons , or one of them is fluorine, and the other is an alkyl group with 1 to 6 carbons, Can be R can be _CH3 , _CH2CH3 , CH( _CH3 ) ₂ , C( _CH3 ) ₃ , _CF3 , _CHF2 , _C3F8 or ph, and n= ₂ or ₃ , and m=0 Or 1, and n+m=3.

In some embodiments, the material of the cathode 18 may include lithium, magnesium, calcium, aluminum, silver, indium, gold, tungsten, nickel, platinum or copper.

In some embodiments, each layer of the organic light emitting diode 10 can be formed by methods such as thermal evaporation, sputtering, or plasma enhanced chemical vapor deposition.

In some embodiments, the organic light emitting diode 10 can emit blue light, and it can be an organic light emitting diode with top emission, bottom emission or dual emission.

According to an embodiment of the present disclosure, it is an organic light emitting diode (OLED). Please refer to FIG. 2 . FIG. 2 is a schematic cross-sectional view of an organic light emitting diode according to the present disclosure. The organic light emitting diode 100 includes a substrate 120, an anode 140, a hole transport layer (hole transport layer, HTL) 150, a first light emitting layer 160, a second light emitting layer 160', an electron transport layer (electron transport layer, ETL) 170 And the cathode 180, wherein the anode 140 is disposed on the substrate 120, the hole transport layer 150 is disposed on the anode 140, the first light emitting layer 160 is disposed on the hole transport layer 150, and the second light emitting layer 160' is disposed on the first light emitting layer 160 , the electron transport layer 170 is disposed on the second light emitting layer 160 ′, and the cathode 180 is disposed on the electron transport layer 170 .

In some embodiments, the material of the substrate 120 may include glass, plastic or semiconductor.

In some embodiments, the material of the anode 140 may include indium tin oxide (ITO), indium zinc oxide (IZO), zinc aluminum oxide (AZO), zinc oxide (ZnO) or combinations thereof.

In some embodiments, the material of the hole transport layer (HTL) 150 and the electron transport layer (ETL) 170 may include

In some embodiments, the first light-emitting layer 160 and the second light-emitting layer 160' may include a host material (host) and a dopant (dopant).

In some embodiments, the primary emitter material may include

In some embodiments, the dopant may include an organometallic complex having the following chemical formula (I).

In the chemical formula (I), one of R ₁ and R ₂ is trimethylsilyl (trimethylsilyl, TMS), the other is hydrogen, and at least one of R ₃ and R ₄ is fluorine or an alkyl group with 1 to 6 carbons , or one of them is fluorine, and the other is an alkyl group with 1 to 6 carbons, Can be R can be _CH3 , _CH2CH3 , CH( _CH3 ) ₂ , C( _CH3 ) ₃ , _CF3 , _CHF2 , _C3F8 or ph, and n= ₂ or ₃ , and m=0 Or 1, and n+m=3.

In some embodiments, the material of the cathode 180 may include lithium, magnesium, calcium, aluminum, silver, indium, gold, tungsten, nickel, platinum or copper.

In some embodiments, each layer of the organic light emitting diode 100 can be formed by, for example, thermal evaporation, sputtering, or plasma enhanced chemical vapor deposition.

In some embodiments, the organic light emitting diode 100 can emit blue light, which can be an organic light emitting diode with top emission, bottom emission or dual emission.

The present disclosure develops a phosphorescent material for OLED elements. The chemical structure of the novel phosphorescent material for OLED elements is the use of trimethylsilyl (trimethylsilyl, TMS)-containing ligands and auxiliary ligands. The base and Ir metal form a hexacoordinated complex. This phosphorescent complex light-emitting material has appropriate HOMO and LUMO energy levels (between 6.0eV and 3.0eV), and excellent thermal stability, which can effectively combine holes and The electrons transform to form excitons (excitons) and then release phosphorescence, which effectively improves the luminous efficiency of the OLED element.

The structure of the phosphorescent material disclosed in the present disclosure utilizes the stable bond between the metal center and the ligand to improve thermal stability, and at the same time adjusts the energy level position of the metal complex. It is expected that the combination of different ligands can achieve a bluer light color. Light-emitting materials and improve the efficiency of PHOLED components.

Example 1

Synthesis of the Disclosed Organometallic Complex (DFTIr(taz))

step 1:

Prepare a 100mL double-necked bottle, after repeated dehydration and deoxygenation, fill with nitrogen, add 2,5-dibromopyridine (2,5-dibromopyridine, 1g, 4.22mmol) and 40mL of anhydrous Solvent diethyl ether (ether), then, cool the reaction flask to -78°C, wait for the temperature of the reaction flask to balance, add a strong base n-BuLi (3mL, 4.64mmol) dropwise with a syringe, after the addition, let the reaction proceed at - Continue the reaction at 78°C for one hour, then add trimethylchlorosilane TMSCl (trimethyl chlorosilane) (0.65mL, 5mmol) at low temperature, remove the low temperature tank and allow the reaction to gradually return to room temperature, and extract three times with EA and water, And the organic layer collected three times was dried and filtered, and after being sucked dry by a cyclone concentrator, it was purified by column chromatography (silica, ethyl acetate/hexane=1/40) to obtain 2- Bromo-5-trimethylsilylpyridine (2-bromo-5-trimethylsilylpyridine).

Step 2:

Prepare a 100mL double-necked flask, add 2-bromo-5-trimethylsilylpyridine (0.7g, 3mmol), 2,4-difluoropyridine bromic acid (2,4-difluoropyridine bromic acid) (0.52g , 3.3mmol) and K ₂ CO ₃ (0.4g, 1mmol), then, add 20mL of dimethoxyethane (dimethoxyethane) and 10mL of water as a solvent, then add a catalytic amount of Pd(PPh ₃ ) ₄ (0.17 g, 0.15mmol), after repeated dehydration and deoxygenation drying, filled with nitrogen, then, the reaction was heated to reflux, reacted overnight, the reaction was returned to room temperature, added NaHCO ₃ aqueous solution to neutralize the reaction to a weak base (pH 8 ~10), extract three times with EA and water, dry and filter the organic layer collected three times, and use a cyclone concentrator to dry it, then perform column chromatography for purification to obtain compound A, TLC tablet The properties are EA/Hexane (n-hexane) = 1/40, R _f = 0.2.

Step 3:

Prepare a 100mL two-necked flask, add compound A (1.7g, 6.6mmol) and IrCl ₃ (0.89g, 3mmol), then add 24mL of 2-methoxyethanol (2-methoxyethanol) and 8mL of water as solvent , after repeated dehydration, deoxygenation and drying, filled with nitrogen, heated the reaction to 120°C, reacted overnight, returned the reaction to room temperature, added water to precipitate, filtered the solution and washed the solid with water and n-hexane, collected the solid and Dimer-A can be obtained by vacuum drying.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-A (0.5g, 0.33mmol), ligand (ligand) (285mg, 1.33mmol), weak base trimethylamine (trimethylamine, 0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and oxygen removal, fill with nitrogen, and Heat the reaction to 120°C, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n _- hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water , and the organic layer collected three times was dried and filtered, and after being sucked dry by a cyclone concentrator, it was purified by column chromatography to obtain the organometallic complex (DFTIr(taz)) of this embodiment.

The compound DFTIr(taz) was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.37(d,1H), 8.25(d,1H), 8.21(d,1H), 8.02(t,1H),7.90(d,2H),7.83(d,1H),7.58(s,1H),7.38～7.32(m,2H),5.74(t,1H),5.64(t,1H) ,0.15(s,9H),0.06(s,9H).

Example 2

Synthesis of the Disclosed Organometallic Complex (DFTIr(iaz))

Steps 1-3 are the same as in Example 1.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-A (0.5g, 0.33mmol), ligand (193mg, 1.33mmol), weak base trimethylamine (0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen, and heat the reaction to 120°C, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n _- hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water, and The organic layer collected three times was dried and filtered, and after being sucked dry by a cyclone concentrator, column chromatography was performed for purification to obtain the organometallic complex (DFTIr(iaz)) of this example.

The compound DFTIr(iaz) was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.29～8.17(m,3H), 7.88～7.77(m,3H), 7.67(d ,1H),7.62(s,1H),7.52(s,1H),7.32(s,1H),7.06(t,1H),6.61(s,1H),5.80(t,1H),5.68(t, 1H), 0.13(s,9H), 0.09(s,9H).

Example 3

Synthesis of the Disclosed Organometallic Complex (DFTIr(pic))

Steps 1-3 are the same as in Example 1.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-A (0.5g, 0.33mmol), ligand (164mg, 1.33mmol), weak base trimethylamine (0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen, and heat the reaction to 120°C, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n _- hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water, and The organic layer collected three times was dried and filtered, and then dried by a cyclone concentrator, followed by column chromatography for purification to obtain the organometallic complex (DFTIr(pic)) of this example.

The compound DFTIr(pic) was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.78(s,1H), 8.38(d,1H), 8.27～8.20(m,2H ),8.05(dt,1H),7.80～7.91(m,2H),7.83(d,1H),7.53(t,1H),7.31(s,1H),5.80(s,1H),5.57(s, 1H), 0.31(s,9H), 0.08(s,9H).

Example 4

Synthesis of the Disclosed Organometallic Complex (DFTIr(taz2))

Steps 1-3 are the same as in Example 1.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-A (0.5g, 0.33mmol), ligand (269mg, 1.33mmol), weak base trimethylamine (0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen, and heat the reaction to 120°C, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n _- hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water, and The organic layer collected three times was dried and filtered, and then dried by a cyclone concentrator, followed by column chromatography for purification to obtain the organometallic complex (DFTIr(taz2)) of this example.

The compound DFTIr(taz2) was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.28～8.16(m,3H), 7.91～7.83(m,3H),7.72(s ,1H),7.70(d,1H),7.45(s,1H),7.15(t,1H),5.69～5.66(m,2H),1.37(s,9H),0.17(s,9H),0.08( s, 9H).

Example 5

Synthesis of the Disclosed Organometallic Complex (DFTIr(Miaz))

Steps 1-3 are the same as in Example 1.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-A (0.5g, 0.33mmol), ligand (229mg, 1.33mmol), weak base trimethylamine (0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen, and heat the reaction to 120°C, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n _- hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water, and The organic layer collected three times was dried and filtered, and then dried by a cyclone concentrator, followed by column chromatography for purification to obtain the organometallic complex (DFTIr(Miaz)) of this example.

The compound DFTIr(Miaz) was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.35～8.22(m,3H),7.95～7.80(m,3H),7.70(d ,1H),7.65(s,1H),7.50(s,1H),7.35(s,1H),7.10(t,1H),6.61(s,1H),3.51(s,3H),3.12(s, 3H), 0.15(s,9H), 0.08(s,9H).

Example 6

Synthesis of the Disclosed Organometallic Complex (DFTIr(acac))

Steps 1-3 are the same as in Example 1.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-A (0.5g, 0.33mmol), ligand (133mg, 1.33mmol), weak base trimethylamine (0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen, and heat the reaction to 120°C, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n _- hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water, and The organic layer collected three times was dried and filtered, and after being sucked dry by a cyclone concentrator, column chromatography was performed for purification to obtain the organometallic complex (DFTIr(acac)) of this example.

The compound DFTIr(acac) was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.45(s, 2H), 8.22(d, 2H), 7.97(d, 2H), 5.65(t, 2H), 5.33(s, 1H), 1.85(s, 6H), 0.35(s, 18H).

Example 7

Synthesis of the Disclosed Organometallic Complex (DFTIr(tmd))

Steps 1-3 are the same as in Example 1.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-A (0.5g, 0.33mmol), ligand (245mg, 1.33mmol), weak base trimethylamine (0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen, and heat the reaction to 120°C, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n _- hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water, and The organic layer collected three times was dried and filtered, and then dried by a cyclone concentrator, followed by column chromatography for purification to obtain the organometallic complex (DFTIr(tmd)) of this example.

The compound DFTIr(tmd) was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.31(s, 2H), 8.17(d, 2H), 7.90(d, 2H), 5.81(t,2H),5.613(s,1H),0.84(s,18H),0.29(s,18H).

Example 8

Synthesis of the Disclosed Organometallic Complex (DFTIr(hf))

Steps 1-3 are the same as in Example 1.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-A (0.5g, 0.33mmol), ligand (277mg, 1.33mmol), weak base trimethylamine (0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen, and heat the reaction to 120°C, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n _- hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water, and The organic layer collected three times was dried and filtered, and after being sucked dry by a cyclone concentrator, column chromatography was performed for purification to obtain the organometallic complex (DFTIr(hf)) of this example.

The compound DFTIr(hf) was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.27(d,2H), 8.25(s,2H), 8.06(d,2H), 6.09 (s, 1H), 5.60 (t, 2H), 0.34 (s, 18H).

Example 9

Synthesis of the Disclosed Organometallic Complex (DFTIr(dbm))

Steps 1-3 are the same as in Example 1.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-A (0.5g, 0.33mmol), ligand (311mg, 1.33mmol), weak base trimethylamine (0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen, and heat the reaction to 120°C, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n _- hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water, and The organic layer collected three times was dried and filtered, and after being sucked dry by a cyclone concentrator, column chromatography was performed for purification to obtain the organometallic complex (DFTIr(dbm)) of this example.

The compound DFTIr(dbm) was analyzed by nuclear magnetic resonance spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.56(s, 2H), 8.22(d, 2H), 7.92(d, 2H), 7.80 (d, 4H), 7.47～7.31 (m, 6H), 6.67 (s, 1H), 5.76 (t, 2H), 0.15 (s, 18H).

The PL emission spectrum of the DFTIr series organometallic complexes of the present disclosure:

When the commonly used third ligand (acac) is selected to synthesize DFTIr(acac), its PL spectrum is 465nm, which is a phosphorescent material belonging to sky blue. In order to achieve a range of darker blue phosphorescent materials, this disclosure chooses to pull electrons The third ligand with stronger ability (for example: pic, taz or taz2, etc.), as the ability to pull electrons increases, the light color does move in the direction of blue shift. For example, the PL spectrum of DFTIr (pic) has reached 452nm Compared with the currently commercially available blue phosphorescent material FIr(pic) (PL spectrum is 475nm), its blue shift is nearly 23nm, which shows that this type of material has a very good performance in light and color matching. The spectral information is shown in Table 2 below .

Table 2

DFTIr(acac) DFTIr (pic) DFTIr(taz) DFTIr(taz2) 465nm 452nm 447nm 452nm

Example 10

Synthesis of the Disclosed Organometallic Complexes (DFTIr)

Steps 1-3 are the same as in Example 1.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-A (0.37g, 0.25mmol), ligand (200mg, 0.75mmol), AgOCOCF3 (160mg, 0.75mmol), then, add 5mL of diphenyl ether as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen gas, heat the reaction to 165°C, react for two hours, Return the reaction to room temperature, and directly carry out column chromatography for purification, first purify with Hexane, and then use EA/hexane=1/8 column chromatography to obtain the organometallic complex (DFTIr) of this example.

The compound DFTIr was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.33(d, 1H), 8.21(t, 2H), 8.05～7.77(m, 5H), 7.31 (s,1H),6.43(t,1H),5.92(t,1H),5.70(s,1H),0.14(s,9H),0.12(s,9H),0.05(s,9H).

The PL emission spectrum of the DFTIr organometallic complex of the present disclosure:

The DFTIr organometallic complex material with a tris structure is obtained by using special synthesis steps. The PL spectrum is not only greatly reduced to 448nm, but the half-height slope length is only 57nm, and the light color purity is high. In addition to being applicable to the color temperature adjustment of lighting, it needs The display technology application of pure blue light-emitting materials will have the opportunity to use DFTIr blue phosphorescent materials.

Sublimation purification of the DFTIr series organometallic complexes of the present disclosure:

The DFTIr series organometallic complex materials of the present disclosure all have quite excellent thermal stability properties, and the yield of each material after vacuum sublimation purification is close to 100%, which is comparable to that of general commercially available FIr(pic) phosphorescent materials (about 50%) Compared with that, the improvement is quite large. Taking DFTIr(acac) as a representative example, it can be found that after vacuum sublimation and purification, the mother tube has almost no residue or ash after cracking of the luminescent material. The DFTIr(acac) luminescent material is almost 100 % yield was sublimated into a collection tube.

Example 11

Synthesis of the Disclosed Organometallic Complex (DMTIr(taz))

Step 1 is the same as in Example 1.

Step 2:

Prepare a 100mL double-necked flask, add 2-bromo-5-trimethylsilylpyridine (0.7g, 3mmol), 2,4-dimethylpyridine bromic acid (2,4-dimethylpyridine bromic acid) (0.52 g, 3.3mmol) and K ₂ CO ₃ (0.4g, 1mmol), then, add 20mL of dimethoxyethane (dimethoxyethane) and 10mL of water as a solvent, then add a catalytic amount of Pd(PPh ₃ ) ₄ ( 0.17g, 0.15mmol), after repeated dehydration and deoxygenation drying, filled with nitrogen, then, the reaction was heated to reflux, reacted overnight, the reaction was returned to room temperature, added NaHCO ₃ aqueous solution to neutralize the reaction to a weak base (pH 8～10), carry out extraction three times with EA and water, and the organic layer collected three times is dried and filtered, after utilizing cyclone concentrator to drain, carry out column chromatography (silica, ethyl acetate/hexane =1/40) to obtain compound B.

Step 3:

Prepare a 100mL double-necked flask, add compound B (1.7g, 6.6mmol) and IrCl ₃ (0.89g, 3mmol), then add 24mL of 2-methoxyethanol and 8mL of water as solvent, after repeated removal After the water is deoxygenated and dried, fill with nitrogen, heat the reaction to 120°C, react overnight, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n-hexane, collect the solid and dry it in vacuum, that is Dimer-B is available.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-B (0.5g, 0.33mmol), ligand (285mg, 1.33mmol), weak base (0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen, and heat the reaction to 120 ℃, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n-hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water, and _three times The collected organic layer was dried and filtered, sucked dry with a cyclone concentrator, and then purified by column chromatography to obtain the organometallic complex (DMTIr(taz)) of this example.

The compound DMTIr(taz) was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.31(d,1H), 8.11(d,1H), 8.04(d,1H), 7.91(t,1H),7.84～7.78(m,3H),7.69(d,1H),7.50(s,1H),7.22(t,1H),5.92(s,1H),5.83(s,1H) ,2.86(s,6H),2.29(s,3H),2.23(s,3H),0.15(s,9H),0.04(s,9H).

Example 12

Synthesis of the Disclosed Organometallic Complex (DMTIr(iaz))

Steps 1-3 are the same as in Example 11.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-B (0.5g, 0.33mmol), ligand (193mg, 1.33mmol), weak base (0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen, and heat the reaction to 120 ℃, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n-hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water, and _three times The collected organic layer was dried and filtered, sucked dry by a cyclone concentrator, and then purified by column chromatography to obtain the organometallic complex (DMTIr(iaz)) of this example.

The compound DMTIr(iaz) was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.12(d,1H), 8.04(d,1H), 8.01(d,1H), 7.77～7.66(m,5H),7.55(d,1H),7.23(s,1H),6.92(t,1H),6.51(s,1H),6.00(s,1H),5.89(s,1H) ,2.86(s,6H),2.27(s,3H),2.24(s,3H),0.12(s,9H),0.06(s,9H).

Example 13

Synthesis of the Disclosed Organometallic Complex (DMTIr(pic))

Steps 1-3 are the same as in Example 11.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-B (0.5g, 0.33mmol), ligand (164mg, 1.33mmol), weak base (0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen, and heat the reaction to 120 ℃, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n-hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water, and _three times The collected organic layer was dried and filtered, sucked dry with a cyclone concentrator, and then purified by column chromatography to obtain the organometallic complex (DMTIr(pic)) of this example.

The compound DMTIr(pic) was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.87(s,1H), 8.33(d,1H), 8.10(dd,2H), 7.99～7.85(m,3H),7.71(d,1H),7.45～7.39(m,2H),6.02(s,1H),5.78(s,1H),2.92(s,3H),2.86(s, 3H), 2.26(s,3H), 2.23(s,3H), 0.31(s,9H), 0.07(s,9H).

Example 14

Synthesis of the Disclosed Organometallic Complex (DMTIr(acac))

Steps 1-3 are the same as in Example 11.

Step 4:

Prepare a 10mL round bottom bottle, add Dimer-B (0.5g, 0.33mmol), ligand (133mg, 1.33mmol), weak base (0.1mL, 1.33mmol), then, add 5mL of 2-methoxyethanol as a solvent, after repeated dehydration and deoxygenation, fill with nitrogen, and heat the reaction to 120 ℃, react for three hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n-hexane, collect the solid and dissolve it with _CH2Cl2 , extract _three times with _CH2Cl2 and water, and _three times The collected organic layer was dried and filtered, sucked dry with a cyclone concentrator, and purified by column chromatography to obtain the organometallic complex (DMTIr(acac)) of this example.

The compound DMTIr(acac) was analyzed by NMR spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl ₃ , 294K): 8.57(s, 2H), 8.07(d, 2H), 7.89(d, 2H), 5.90(s,2H), 5.24(s,1H), 2.84(s,6H), 2.19(s,6H), 1.79(s,6H), 0.33(s,18H).

Comparative Example 1

Synthesis of Organometallic Complex (DFTIr(acac)-O)

step 1:

Prepare a 100mL two-necked flask, add 12.5g (110.0mmol) of 2,5-difluoropyridine (2,5-difluoropyrdine), 100mL of acetic acid and 15.0g (440mmol) of 30% hydrogen peroxide, and put it under a nitrogen device Heat the reaction to 70°C and react for 10 hours. After the reaction is completed, add NaHCO ₃ aqueous solution to neutralize the reaction to a weak base, extract three times with EA and water, and dry and filter the organic layer collected three times. After the concentrator was drained, the obtained crude product was directly carried out to the next step.

Step 2:

Prepare a 250mL double-neck flask, add 6g (45mmol) of the starting material and 150mL of anhydrous THF solvent, after repeated deoxygenation and drying, fill with nitrogen, then immerse the reaction device in the environment of -78°C, wait until the temperature After equilibration, slowly drop 22g of LDA (55mmol) into the reaction bottle with a syringe, react at low temperature for about 1 hour, add water to stop the reaction, and use 1N HCl to adjust the pH value of the water to weak acidity, and add EA and water Extraction was performed three times, and the organic layer collected three times was dried and filtered, and after being sucked dry by a cyclone concentrator, the obtained crude product was directly subjected to the next step.

Step 3:

Prepare a 100mL two-necked flask, add 2-bromo-5-trimethylsilylpyridine (0.7g, 3mmol), 2,4-difluoropyridine bromide (0.58g, 3.3mmol) with N-oxide, K ₂ CO ₃ (0.4g, 1mmol), followed by adding 20mL of dimethoxyethane and 10mL of water as a solvent, and then adding a catalytic amount of Pd(PPh ₃ ) ₄ , after repeated dehydration and oxygen drying, filled with Nitrogen, then heated the reaction to reflux, reacted overnight, returned the reaction to room temperature, added NaHCO ₃ aqueous solution to neutralize the reaction to a weak base, extracted three times with EA and water, and dried and filtered the organic layer collected three times, using After being drained by a cyclone concentrator, it was purified by column chromatography. The polarity of the TLC chip was ethyl acetate/hexane=1/10, and R _f =0.34.

Step 4:

Prepare a 100mL two-necked flask, add compound AO (1.8g, 6.6mmol) and IrCl ₃ (0.89g, 3mmol), then add 24mL 2-methoxyethanol and 8mL of water as solvent, after repeated dehydration and oxygen drying After filling with nitrogen, the reaction was heated to 120° C., reacted overnight, the reaction was returned to room temperature, and water was added to precipitate, the solution was filtered and the solid was washed with water and n-hexane, and the solid was collected and dried under vacuum.

Step 5:

Prepare a 10mL round bottom bottle, add Dimer-AO (0.57g, 0.33mmol), ligand (133mg, 1.33mmol), weak base (0.1mL, 1.33mmol), then add 5mL of 2-methoxyethanol When the solvent, after repeated dehydration and deoxygenation, fill with nitrogen, heat the reaction to 120°C, react for 3-5 hours, return the reaction to room temperature, add water to precipitate, filter the solution and wash the solid with water and n-hexane , the solid was collected and dissolved with CH ₂ Cl ₂ , extracted three times with CH ₂ Cl ₂ and water, and the organic layer collected three times was dried and filtered. The organometallic complex (DFTIr(acac)-O) of this example can be obtained.

The compound (DFTIr(acac)-O) was analyzed by nuclear magnetic resonance spectroscopy, and the obtained spectral information is as follows: ¹ H NMR (200MHz, CDCl3, 294K): 8.41(d, 2H), 8.16(d, 2H), 7.81(d, 2H), 5.62(t, 2H), 5.25(s, 1H), 1.80(s, 6H), 0.34(s, 18H).

Example 15

Fabrication of the organic light-emitting diode (1) of the present disclosure (evaporation process)

Clean the patterned ITO (thickness 150 nm) glass substrate with ultrasonic vibration using neutral detergent, acetone and ethanol. Next, dry the substrate with nitrogen, and then perform UV-OZONE for 30 minutes. Afterwards, a TAPC layer (40 nm in thickness), a 26DCzPPy-doped complex DFTIr(acac) layer (the ratio of 26DCzPPy to the complex DFTIr(acac) is 10:1) was deposited sequentially under a pressure of 10 ^-6 torr (thickness is 10nm), TmPyPB layer (thickness is 50nm), LiF layer (thickness is 0.8nm) and Al layer (thickness is 120nm), obtain organic light-emitting diode (1) after packaging. The structure of the organic light emitting diode (1) of this embodiment can be expressed as:

ITO(150nm)/TAPC(40nm)/26DCzPPy:complex DFTIr(acac)(10%)(10nm)/TmPyPB(50nm)/LiF(0.8nm)/Al(120nm).

Next, measure the optical properties of the organic light emitting diode (1) (including current efficiency (cd/A), power efficiency (lm/W), emission wavelength (nm), color coordinates (x, y)), and the measurement results It is described in Table 3 below.

Example 16

Fabrication of the disclosed organic light-emitting diode (2)

The manufacturing method of the organic light-emitting diode (2) in this embodiment is similar to that of Embodiment 15, except that the main light-emitting material doped complex layer is made by doping TCTA with the complex DFTIr(acac). The structure of the organic light emitting diode (2) of this embodiment can be expressed as:

ITO(150nm)/TAPC(40nm)/TCTA:complex DFTIr(acac)(10%)(10nm)/TmPyPB(50nm)/LiF(0.8nm)/Al(120nm).

Next, measure the optical properties of the organic light emitting diode (2) (including current efficiency (cd/A), power efficiency (lm/W), emission wavelength (nm), color coordinates (x, y)), and the measurement results are presented in Table 3 below.

Comparative Example 2

Fabrication of Traditional Organic Light Emitting Diodes

The manufacturing method of the traditional organic light-emitting diode in this comparative example is similar to that of Example 15, the difference is that the doped complex layer of the main light-emitting material is made of complex FK306 Made by doping mCP.

Next, measure the optical characteristics of traditional organic light-emitting diodes (including current efficiency (cd/A), power efficiency (lm/W), emission wavelength (nm), color coordinates (x, y)), and the measurement results are recorded in Table 3 below.

table 3

Here, different main illuminant materials are used to test the blue phosphorescent OLED components, and the blue phosphorescent dopant material DFTIr (acac) is doped into the two main illuminant materials of 26DCzPPy and TCTA respectively to form an organic light emitting diode ( 1) and organic light-emitting diodes (2). Compared with FK306, which has a similar structure to DFTIr(acac), DFTIr(acac) blue phosphorescent materials have better device performance, especially under the condition of using 26DCzPPy as the main emitter material (organic light-emitting diode (1 )) The increased range is relatively large, and can be increased by about 16% when the brightness is 1000cd/m ² , and the CIE performance of the two is quite similar.

Example 17

Optical characteristic analysis of organic light-emitting diodes doped with various light-emitting dopant materials of the present disclosure

It can be seen from the results in Table 3 that when the main illuminant material is 26DCzPPy, the element has better efficiency performance. Therefore, in this embodiment, the element test of the main illuminant material 26DCzPPy with various luminescent dopant materials is carried out. The characteristic data are shown in Table 4 below. The DFTIr(tmd) formed by the third ligand with a large steric barrier (tmd) has a device efficiency and light color that are quite close to DFTIr(acac), while the DFTIr(tmd) with a stronger electron-withdrawing group The third ligands such as (pic), (taz) and (taz2), etc., although the blue light color is shifted by 12-16nm, the efficiency still exceeds 10lm/W, which shows that this type of light-emitting material has a very good device efficiency performance. . In addition, although DMTIr (acac) is a blue-green light-emitting material, it has a device efficiency performance as high as 57.2lm/W, and has the opportunity to be used in various high-efficiency light-emitting devices in the future.

Table 4

Example 18

Fabrication of the organic light-emitting diode (3) of the present disclosure (solution process)

Clean the patterned ITO (thickness 150 nm) glass substrate with ultrasonic vibration using neutral detergent, acetone and ethanol. Next, dry the substrate with nitrogen, and then perform UV-OZONE for 30 minutes. Afterwards, PEDOT:PSS was selected as the hole injection layer, and a film layer (thickness 40 nm) was formed by spin coating (rotating speed 2,000 rpm). Then, heating was carried out at 130° C. for 10 minutes. Next, a light-emitting layer (with a thickness of about 30 nm) was formed on the PEDOT:PSS layer by spin coating. The light-emitting layer includes the main light-emitting material mCP and the complex DFTIr(acac). Take the weight ratio mCP:complex DFTIr(acac)=4:1 and dissolve in chlorobenzene (chlorobenzene) solvent to make the light-emitting layer. Next, a hole-blocking and electron-transporting layer—TmPyPB layer (with a thickness of about 45 nm) was deposited on the light-emitting layer. Next, deposit a LiF layer (with a thickness of 1 nm) and an Al layer (with a thickness of 100 nm), and obtain an organic light-emitting diode (3) after packaging. The structure of the organic light emitting diode (3) can be expressed as:

ITO(150nm)/PEDOT:PSS(40nm)/mCP:complex DFTIr(acac)(30nm)/TmPyPB(45nm)/LiF(1nm)/Al(100nm).

Next, measure the optical properties of the organic light emitting diode (3) (including current efficiency (cd/A), power efficiency (lm/W), emission wavelength (nm), color coordinates (x, y)), and the measurement results It is described in Table 5 below.

Example 19

Fabrication of the disclosed organic light-emitting diode (4)

The fabrication method of the organic light-emitting diode (4) of this embodiment is similar to that of embodiment 18, except that the light-emitting layer includes the main light-emitting material TCTA and the complex DFTIr(acac). The structure of the organic light emitting diode (4) can be expressed as:

ITO(150nm)/PEDOT:PSS(40nm)/TCTA:complex DFTIr(acac)(30nm)/TmPyPB(45nm)/LiF(1nm)/Al(100nm).

Next, measure the optical properties of the organic light emitting diode (4) (including current efficiency (cd/A), power efficiency (lm/W), emission wavelength (nm), color coordinates (x, y)), and the measurement results It is described in Table 5 below.

Example 20

Fabrication of the disclosed organic light-emitting diode (5)

The manufacturing method of the organic light-emitting diode (5) in this embodiment is similar to that in Embodiment 19, except that the light-emitting layer includes the main light-emitting material TCTA and the complex DFTIr(tmd). The structure of the organic light emitting diode (5) can be expressed as:

ITO(150nm)/PEDOT:PSS(40nm)/TCTA:complex DFTIr(tmd)(30nm)/TmPyPB(45nm)/LiF(1nm)/Al(100nm).

Next, measure the optical characteristics (comprising current efficiency (cd/A), power efficiency (lm/W), luminous wavelength (nm), color coordinates (x, y)) of organic light-emitting diode (5), measure the result It is described in Table 5 below.

Example 21

Fabrication of the disclosed organic light-emitting diode (6)

The fabrication method of the organic light-emitting diode (6) of this embodiment is similar to that of embodiment 19, except that the light-emitting layer includes the main light-emitting material TCTA and the complex DMTIr(acac). The structure of the organic light emitting diode (6) can be expressed as:

ITO(150nm)/PEDOT:PSS(40nm)/TCTA:complex DMTIr(acac)(30nm)/TmPyPB(45nm)/LiF(1nm)/Al(100nm).

Next, measure the optical properties (including current efficiency (cd/A), power efficiency (lm/W), luminous wavelength (nm), color coordinates (x, y)) of the organic light-emitting diode (6), and the measurement results It is described in Table 5 below.

Example 22

Fabrication of the disclosed organic light-emitting diode (7)

The fabrication method of the organic light-emitting diode (7) of this embodiment is similar to that of embodiment 19, except that the light-emitting layer includes the main light-emitting material TCTA and the complex DMTIr(pic). The structure of the organic light emitting diode (7) can be expressed as:

ITO(150nm)/PEDOT:PSS(40nm)/TCTA:complex DMTIr(pic)(30nm)/TmPyPB(45nm)/LiF(1nm)/Al(100nm).

Next, measure the optical characteristics (comprising current efficiency (cd/A), power efficiency (lm/W), luminous wavelength (nm), color coordinates (x, y)) of organic light-emitting diode (7), measurement result It is described in Table 5 below.

Comparative Example 3

Fabrication of Traditional Organic Light Emitting Diodes

The manufacturing method of the traditional organic light-emitting diode in this comparative example is similar to that of Example 19, except that the light-emitting layer includes the main light-emitting material TCTA and the complex FTIr(pic).

Next, measure the optical characteristics of traditional organic light-emitting diodes (including current efficiency (cd/A), power efficiency (lm/W), emission wavelength (nm), color coordinates (x, y)), and the measurement results are recorded in Table 5 below.

table 5

The solubility of the DFTIr series organometallic complexes of the present disclosure is quite good (>4wt%), therefore, they can be mixed very uniformly with the main illuminant material TCTA or mCP. The organic light-emitting diodes (4) and (5) doped with DFTIr(acac) and DFTIr(tmd) both exhibit good device efficiencies, and the energy efficiency reaches 10.7 and 10.9lm/W at 1,000cd/m ² , respectively. Quite excellent data in the solution process of pure blue light. In addition, in the DMTIr series of luminescent materials, the light color of DMTIr(pic) is close to that of the commercially available luminescent material FTIr(pic), and under the conditions of the solution process, the components made of DMTIr(pic) (organic light-emitting diodes (7 )) At 1,000cd/m ² , the device efficiency reaches 17.1lm/W, which is about 14% higher than that of FTIr(pic), which means that the DMTIr series also has a good performance in solution process.

Example 23

Fabrication of the organic light-emitting diode (8) of the present disclosure (evaporation process)

Clean the patterned ITO (thickness 150 nm) glass substrate with ultrasonic vibration using neutral detergent, acetone and ethanol. Next, dry the substrate with nitrogen, and then perform UV-OZONE for 30 minutes. Afterwards, a TAPC layer (35 nm in thickness), a TCTA-doped complex DFTIr(tmd) layer (the ratio of TCTA to the complex DFTIr(tmd) is 1:0.05) was deposited sequentially under a pressure of 10 ^-6 torr (thickness is 35 nm). 6nm), 26DCzPPy doped complex DFTIr(tmd) layer (the ratio of 26DCzPPy to complex DFTIr(tmd) is 1:0.06) (thickness is 6nm), TmPyPB layer (thickness is 110nm), LiF layer (thickness is 1nm) and an Al layer (thickness is 100nm), and an organic light emitting diode (8) is obtained after packaging. The structure of the organic light emitting diode (8) in this embodiment can be expressed as:

ITO(150nm)/TAPC(35nm)/TCTA:complex DFTIr(tmd)(5%)(6nm)/26DCzPPy:complex DFTIr(tmd)(6%)(6nm)/TmPyPB(110nm)/LiF(1nm )/Al(100nm).

Next, measure the optical characteristics (comprising current efficiency (cd/A), power efficiency (lm/W), luminous wavelength (nm), color coordinates (x, y)) of organic light-emitting diode (8), measurement result It is described in Table 6 below.

Example 24

Fabrication of the disclosed organic light-emitting diode (9)

The fabrication method of the organic light-emitting diode (9) of this embodiment is similar to that of Embodiment 23, except that the doped complex layer of the main light-emitting material is made by doping TCTA and 26DCzPPy respectively with the complex DFTIr(acac). The structure of the organic light emitting diode (9) of this embodiment can be expressed as:

ITO(150nm)/TAPC(35nm)/TCTA:complex DFTIr(acac)(6%)(6nm)/26DCzPPy:complex DFTIr(acac)(8%)(6nm)/TmPyPB(110nm)/LiF(1nm )/Al(100nm).

Next, measure the optical characteristics (comprising current efficiency (cd/A), power efficiency (lm/W), luminous wavelength (nm), color coordinates (x, y)) of organic light-emitting diode (9), measure the result It is reported in Table 6 below.

Table 6

In the double-emitting layer system of the present disclosure, the efficiency of the organic light-emitting diode (9) doped with DFTIr(acac) light-emitting material can be increased to 27.2lm/W, while the efficiency of the organic light-emitting diode doped with DFTIr(tmd) light-emitting material The efficiency of the body (8) can even reach the level of 30.2lm/W, which is about 88% higher than that of the element efficiency (16.1lm/W) doped with FK306 in Comparative Example 2. In addition, the device efficiency of the double-emitting layer system of the present disclosure is also better than that of the commercially available material FTIr(pic) doped with a single emitting layer in Comparative Example 3, and the light color is more pure.

Although the present invention has been disclosed above with several preferred embodiments, it is not intended to limit the present invention, and any person skilled in the art should be able to make any changes and modifications without departing from the spirit and scope of the present invention. Therefore The scope of protection of the present invention should be defined by the appended claims.

Claims (8)

1. An organometallic complex having the following formula (I):

wherein,

R₁and R₂Independently of each other, and one of which is trimethylsilyl (trimethylsilyl) and the other is hydrogen;

R₃and R₄Each independently of the others, and at least one is fluorine or C1-6One of the alkyl groups is fluorine, and the other is an alkyl group having 1 to 6 carbon atoms;

is composed ofR is CH₃、CH₂CH₃、CH(CH₃)₂、C(CH₃)₃、CF₃、CHF₂、C₃F₈Or ph; and n + m is 3, n is 2 or 3, and m is 0 or 1.

2. The organometallic complex according to claim 1, wherein the organometallic complex has the following chemical formula (II):

wherein R is₅Is fluorine or C1-C6 alkyl,is composed of R is CH₃、CH₂CH₃、CH(CH₃)₂、C(CH₃)₃、CF₃、CHF₂、C₃F₈Or ph.

3. The organometallic complex according to claim 1, wherein the organometallic complex isWhereinIs composed of R is CH₃、CH₂CH₃、CH(CH₃)₂、C(CH₃)₃、CF₃、CHF₂、C₃F₈Or ph.

4. The organometallic complex according to claim 1, wherein the organometallic complex is

5. An organic light emitting diode comprising:

a substrate;

an anode disposed on the substrate;

a light-emitting layer provided on the anode, wherein the light-emitting layer comprises the organometallic complex according to claim 1, 2, or 3; and

and a cathode disposed on the light-emitting layer.

6. The organic light emitting diode of claim 5, further comprising a second light emitting layer disposed between the light emitting layer and the anode or between the light emitting layer and the cathode.

7. The organic light emitting diode of claim 6, wherein the second light emitting layer comprises the organometallic complex according to claim 1, 2 or 3.

8. The organic light emitting diode as claimed in claim 5, wherein the organic light emitting diode emits blue light.