Organic electroluminescent device and manufacturing method thereof

Abstract

Disclosed is an organic electroluminescent device, comprising a substrate and light emitting units formed in sequence on the substrate, characterized in that, each of the light emitting units comprises a first electrode layer (1), a light emitting layer (2) and a second electrode layer (3), the light emitting layer comprises a host material and a dye, the host material is made of materials having both electron transport capability and hole transport capability; at least one material in the host material has a CT excited triplet state energy level T.sub.1 greater than its n-π excited triplet state energy level S.sub.1, and T.sub.1-S.sub.1≤0.3 eV; or, at least one material in the host material has a CT excited triplet state energy level T.sub.1 greater than its n-π excited triplet state energy level S.sub.1, and T.sub.1-S.sub.1≥1 eV, with the difference between its n-π excited second triplet state energy level and its CT excited first singlet state energy level being in the range of −0.1 eV to 0.1 eV. The organic electroluminescent device configuration can sufficiently utilize the triplet state energy in the host material and the dye to increase the luminous efficiency and prolong the service life of the device.

Claims

1. An organic electroluminescent device, comprising a substrate and light emitting units formed in sequence on the substrate, wherein each of the light emitting units consists of a first electrode layer (1), a light emitting layer (2) and a second electrode layer (3), the light emitting layer comprises a host material and a dye, the host material is an exciplex made from at least two different kinds of thermal activating delayed fluorescence material, or an exciplex made from at least one kind of thermal activating delayed fluorescence material and a hole transport type material, or an exciplex made from at least one kind of thermal activating delayed fluorescence material and an electron transport type material; wherein the exciplex serving as the host material has a CT excited triplet state energy level T.sub.1 greater than its n-π excited triplet state energy level S.sub.1, and T.sub.1-S.sub.1≤0.3 eV; or wherein the exciplex serving as the host material has a CT excited triplet state energy level T.sub.1 greater than its n-π excited triplet state energy level S.sub.1, and T.sub.1-S.sub.1≥1 eV, with the difference between its n-π excited second triplet state energy level and its CT excited first singlet state energy level being in the range of −0.1 eV to 0.1 eV, and the thermal activating delayed fluorescence material has a structure selected from the following structural formulas (1-2), (1-6) to (1-10), (1-12) to (1-15), (1-19) to (1-21), (1-24), (1-25), (1-27) to (1-48), (1-55), (1-59), (1-61), (1-69) to (1-100): ##STR00038## ##STR00039## ##STR00040## ##STR00041## ##STR00042## ##STR00043## ##STR00044## ##STR00045## ##STR00046## ##STR00047## ##STR00048## ##STR00049##

2. The organic electroluminescent device in accordance with claim 1, wherein the host material is an exciplex made from a thermal activating delayed fluorescence material selected from the structural formulas (1-2), (1-6) to (1-10), (1-12) to (1-15), (1-19) to (1-21), (1-24), (1-25), (1-27) to (1-48), (1-55), (1-59), (1-61), (1-69) to (1-100) and a hole transport type material at a mass ratio of 1:9 to 9:1, the hole transport type material is N,N′-di-(1-naphthyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine, N,N′-diphenyl-N,N′-di-(m-methyl-phenyl)-1,1′-biphenyl-4,4′-diamine, 4,4′-cyclohexyl-di-[N,N-di-(4-methyl-phenyl)]-phenylamine, 4,4′-N,N′-di-carbazole-biphenyl, 4,4′,4″-tri-(carbazole-9-yl)-triphenylamine, or 1,3-di-(carbazole-9-yl)-benzene.

3. The organic electroluminescent device in accordance with claim 1, wherein the host material is an exciplex made from a thermal activating delayed fluorescence material selected from the structural formulas (1-2), (1-6) to (1-10), (1-12) to (1-15), (1-19) to (1-21), (1-24), (1-25), (1-27) to (1-48), (1-55), (1-59), (1-61), (1-69) to (1-100) and an electron transport type material at a mass ratio of 1:9 to 9:1, the electron transport type material is tri-(8-oxyquinoline)-aluminum, 2,9-dimethyl-4,7-diphenyl-1,10-o-phenanthroline, 4,7-diphenyl-1,10-o-phenanthroline, di-(2-methyl-8-quinolyl)-4-phenyl-phenoxide-aluminum(III), 1,3,5-tri-(1-phenyl-1H-benzimidazole-2-yl)-benzene, or 1,3,5-tri-[(3-pyridyl)-3-phenyl]-benzene.

4. The organic electroluminescent device in accordance with claim 1, wherein the dye is made of a fluorescence material and/or a phosphorescence material, the fluorescence material has a doping concentration of 0.5-10 wt %, the phosphorescence material has a doping concentration of 0.5-20 wt %.

5. The organic electroluminescent device in accordance with claim 1, wherein the light emitting layer (2) has a thickness of 50 nm-150 nm.

6. The organic electroluminescent device in accordance with claim 1, wherein, the host material is an exciplex made from at least two different kinds of thermal activating delayed fluorescence material selected from the structural formulas (1-2), (1-6) to (1-10), (1-12) to (1-15), (1-19) to (1-21), (1-24), (1-25), (1-27) to (1-48), (1-55), (1-59), (1-61), (1-69) to (1-100).

7. A preparation method of the organic electroluminescent device of claim 1, comprising the following steps: evaporation coating a first electrode layer (1), a light emitting layer (2) and a second electrode layer (3) in sequence on a substrate by using an open mask; wherein the light emitting layer (2) is prepared by co-evaporation coating of a host material and a dye.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In order to make the content of the present invention more easy to be understood clearly, hereinafter, the present invention is further described in detail according to specific embodiments of the present invention with reference to the accompanying drawings, wherein,

(2) The FIGURE is a structural schematic diagram of an organic electroluminescent device of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

(3) The present invention is further described hereinafter by illustrating specific embodiments.

(4) The present invention can be implemented in many different forms, and should not be interpreted to be limited to the embodiments described herein. On the contrary, by providing these embodiments, the present disclosure is made complete and thorough, and the inventive concept of the present invention is sufficiently conveyed to those skilled in the art, wherein the present invention is defined by the Claims. In the accompanying drawings, for the sake of clarity, dimensions and relative sizes of layers and areas might be exaggerated. It should be understood that, when one element such as a layer, an area or a substrate plate is described as “formed on” or “configured on” another element, this one element may be configured directly upon that another element, or there may exist intermediate element(s). On the contrary, when one element is described as “directly formed upon” or “directly configured upon” another element, there exist no intermediate element.

(5) As shown in the FIGURE, an organic electroluminescent device in the present invention comprises a substrate and light emitting units formed in sequence on the substrate, wherein, each of the light emitting units comprises a first electrode layer 1, a light emitting layer 2 and a second electrode layer 3; the light emitting layer comprises a host material and a dye; the host material is made of materials having both electron transport capability and hole transport capability; at least one material in the host material has a CT excited triplet state energy level T.sub.1 greater than its n-π excited triplet state energy level S.sub.1, and T.sub.1-S.sub.1≤ltoreq. 0.3 eV; or, at least one material in the host material has a CT excited triplet state energy level T.sub.1 greater than its n-π excited triplet state energy level S.sub.1, and T.sub.1-S.sub.1≥1 eV, with the difference between its n-τ excited second triplet state energy level and its CT excited first singlet state energy level being in the range of −0.1 eV to 0.1 eV.

(6) A thermal activating delayed fluorescence material is a material in which there exists charge transfer transition. Both donor group units and receptor group units exist simultaneously in a thermal activating delayed fluorescence material, which gives the thermal activating delayed fluorescence material both electron transport capability and hole transport capability, wherein, the donor group unit is one donor group or a group formed by two or more donor groups being connected together, the receptor group unit is one receptor group or a group formed by two or more receptor groups being connected together. In particular, the thermal activating delayed fluorescence material has a structure selected from the structural formulas (1-1) to (1-100).

(7) The host material in the present invention may be an exciplex made from a single thermal activating delayed fluorescence material, or an exciplex made from an electron transport type material and a hole transport type material, or a composition made from a thermal activating delayed fluorescence material (TADF) and a hole transport type material, or a composition made from a thermal activating delayed fluorescence material (TADF) and an electron transport type material.

(8) The electron transport type material is tri-(8-oxyquinoline)-aluminum, 2,9-dimethyl-4,7-diphenyl-1,10-o-phenanthroline, 4,7-diphenyl-1,10-o-phenanthroline, di-(2-methyl-8-quinolyl)-4-phenyl-phenoxide-aluminum(III), 1,3,5-tri-(1-phenyl-1H-benzimidazole-2-yl)-benzene, or 1,3,5-tri-[(3-pyridyl)-3-phenyl]-benzene.

(9) TABLE-US-00001 Abbreviation Full name Structural formula A1q3 tri-(8-oxyquinoline)-aluminum 0 BCP 2,9-dimethyl-4,7-diphenyl-1,10- o-phenanthroline Bphen 4,7-diphenyl-1,10-o-phenanthroline BAlq di-(2-methyl-8-quinolyl)-4-phenyl- phenoxide-aluminum(III) TPBi 1,3,5-tri-(1-phenyl-1H-benzimidazole-2-yl)- benzene TmPyPB 1,3,5-tri-[(3-pyridyl)-3-phenyl]-benzene

(10) The hole transport type material is N,N′-di-(1-naphthyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine, N,N′-diphenyl-N,N′-di-(m-methyl-phenyl)-1,1′-biphenyl-4,4′-diamine, 4,4′-cyclohexyl-di-[N,N-di-(4-methyl-phenyl)]-phenylamine, 4,4′-N,N′-di-carbazole-biphenyl, 4,4′,4″-tri-(carbazole-9-yl)-triphenylamine, or 1,3-di-(carbazole-9-yl)-benzene.

(11) TABLE-US-00002 Abbreviation Full name Structural formula NPB N,N′-di-(1-naphthyl)-N,N′-diphenyl- 1,1′-biphenyl-4,4′-diamine TPD N,N′-diphenyl- N,N′-di-(m-methyl-phenyl)- 1,1′-biphenyl-4,4′-diamine TAPC 4,4′-cyclohexyl- di-[N,N-di-(4-methyl-phenyl)]- phenylamine CBP 4,4′-N,N′-di-carbazole-biphenyl TCTA 4,4′,4″-tri-(carbazole-9-yl)- triphenylamine 0 mCP 1,3-di-(carbazole-9-yl)-benzene

(12) The red dye used in the present invention is selected from the following structural formulas:

(13) ##STR00032## ##STR00033## ##STR00034##

(14) The green dye used in the present invention is selected from the following structural formulas:

(15) ##STR00035## ##STR00036##

(16) The blue dye used in the present invention is selected from the following structural formulas:

(17) ##STR00037##

Embodiment 1

(18) A device 1 of this embodiment has the following structure:

(19) glass/ITO/(1-24):CBP:Ir(piq).sub.2(acac)(5%)/cathode

(20) The device 1 consists of a substrate, an anode layer, a light emitting layer and a cathode layer, without any hole injection layer, hole transport layer, electron injection layer or electron transport layer. The host material of the light emitting layer is made from the thermal activating delayed fluorescence material of the formula (1-24) and the hole transport type material of CBP, at a mass ratio of 1:1.

(21) The preparation method of the device 1 is as follows: evaporation coating an anode layer (ITO), a light emitting layer and a cathode layer (cathode) in sequence on a substrate by using an open mask, wherein the light emitting layer is prepared by co-evaporation coating of a host material (1-24):CBP and a dye Ir(piq).sub.2(acac), the doping concentration of the dye Ir(piq).sub.2(acac) is 5 wt %.

Embodiment 2

(22) A device 2 of this embodiment has the following structure:

(23) glass/ITO/(1-88):BAlq:Ir(piq).sub.2(acac)(5%)/cathode

(24) In the device 2, the host material of the light emitting layer is made from an electron transport type material and the thermal activating delayed fluorescence material of the formula (1-88), at a mass ratio of 1:1. Herein, the thermal activating delayed fluorescence material serves as a hole transport type material.

(25) The preparation method of the device 2 comprises the steps of evaporation coating an anode layer (ITO), a light emitting layer and a cathode layer (cathode) in sequence on a substrate by using an open mask, wherein the light emitting layer is prepared by co-evaporation coating of a host material (1-88):BAlq and a dye Ir(piq).sub.2(acac), the doping concentration of the dye Ir(piq).sub.2(acac) is 5 wt %.

Embodiment 3

(26) A device 3 of this embodiment has the following structure:

(27) glass/ITO/(1-88):(1-24):Ir(piq).sub.2(acac)(5%)/cathode

(28) In the device 3, the host material of the light emitting layer is an exciplex made from an electron transport type thermal activating delayed fluorescence material and a hole transport type thermal activating delayed fluorescence material), at a mass ratio of 1:1.

(29) The preparation method of the device 3 is as follows: evaporation coating an anode layer (ITO), a light emitting layer and a cathode layer (cathode) in sequence on a substrate by using an open mask, wherein the light emitting layer is prepared by co-evaporation coating of a host material (1-88):(1-24) and a dye Ir(piq).sub.2(acac), the doping concentration of the dye Ir(piq).sub.2(acac) is 5 wt %.

Comparison Example 1

(30) A comparison device 1 of this example has the following structure:

(31) glass/ITO/HIL/HTL/CBP:Ir(piq).sub.2(acac)(5%)/HBL/ETL/cathode

Comparison Example 2

(32) A comparison device 2 of this example has the following structure:

(33) glass/ITO/HIL/HTL/BAlq:Ir(piq).sub.2(acac)(20%)/HBL/ETL/cathode

Comparison Example 3

(34) A comparison device 3 of this example has the following structure:

(35) glass/ITO/HIL/HTL/CBP:BAlq:Ir(piq).sub.2(acac)(5%)/HBL/ETL/cathode

(36) TABLE-US-00003 TABLE 1 Luminous External Brightness efficiency quantum Service life T.sub.90 Device (cd/m.sup.2) (cd/A) efficiency (%) (hrs) Device 1 5000 22 24 500 Device 2 5000 25 23 625 Device 3 5000 29 26 648 Comparison 5000 13 15 430 device 1 Comparison 5000 16 16 472 device 2 Comparison 5000 19 16 498 device 3

Embodiments 4-12

(37) Devices 4-12 of these embodiments have the following structure:

(38) glass/ITO/TADF:hole transport type material:fluorescence material/cathode

(39) Wherein, the respective materials and mass ratios of the TADF, the hole transport type material and the fluorescence material are listed in Table 2.

(40) Wherein the doping concentration of the fluorescence material refers to the ratio that the fluorescence material accounts for in the total mass of the light emitting layer, that is, the fluorescence material doping concentration=the fluorescence material mass/(the fluorescence material mass+the TADF mass+the hole transport type material mass)*100%.

(41) The preparation method of the devices 4-12 comprises the step of evaporation coating an anode layer (ITO), a light emitting layer and a cathode layer (cathode) in sequence on a substrate by using an open mask, wherein the light emitting layer is prepared by co-evaporation coating of a host material (TADF:hole transport type material) and a fluorescence material.

(42) TABLE-US-00004 TABLE 2 doping Hole concen- trans- tration port of the type Mass fluorescence fluorescence TADF material ratio material material Device 4 Formula (1-1) NPB 1:9 DCJT 15 wt %  Device 5 Formula (1-2) TCTA 2:8 BCzVBi 15 wt %  Device 6 Formula (1-3) CBP 3:7 DPAVBi 5 wt % Device 7 Formula (1-4) mCP 4:5 BCzVBi 5 wt % Device 8 Formula (1-5) TPD 5:4 DCJT 5 wt % Device 9 Formula (1-6) TAPC 6:3 DCJT 5 wt % Device 10 Formula (1-11) CBP 7:2 BCzVBi 5 wt % Device 11 Formula (1-15) mCP 8:1 DPAVBi 5 wt % Device 12 Formula (1-20) mCP 9:1 BCzVBi 5 wt %

Embodiments 13-30

(43) Devices 13-30 of these embodiments have the following structure:

(44) glass/ITO/TADF:electron transport type material:fluorescence material/cathode

(45) Wherein, the respective materials and mass ratios of the TADF, the electron transport type material and the fluorescence material are listed in Table 3.

(46) Wherein the doping concentration of the fluorescence material refers to the ratio that the fluorescence material accounts for in the total mass of the light emitting layer, that is, the fluorescence material doping concentration=the fluorescence material mass/(the fluorescence material mass+the TADF mass+the electron transport type material mass)*100%.

(47) The preparation method of the devices 13-30 comprises the step of evaporation coating an anode layer (ITO), a light emitting layer and a cathode layer (cathode) in sequence on a substrate by using an open mask, wherein the light emitting layer is prepared by co-evaporation coating of a host material (TADF:electron transport type material) and a fluorescence material.

(48) TABLE-US-00005 TABLE 3 doping concen- Electron tration transport fluores- of the fluo- type Mass cence rescence TADF material ratio material material Device 13 Formula (1-21) TmPyPB 1:9 DCJT 5 wt % Device 14 Formula (1-22) TPBi 2:8 BCzVBi 5 wt % Device 15 Formula (1-23) BCP 3:7 DPAVBi 5 wt % Device 16 Formula (1-24) Bphen 4:5 BCzVBi 5 wt % Device 17 Formula (1-25) BCP 5:4 DCJT 5 wt % Device 18 Formula (1-26) Alq3 6:3 BCzVBi 5 wt % Device 19 Formula (1-31) Bphen 7:2 DPAVBi 5 wt % Device 20 Formula (1-35) BCP 8:1 BCzVBi 5 wt % Device 21 Formula (1-40) BAlq 9:1 DCJT 5 wt % Device 22 Formula (1-45) Alq3 1:9 DCM 5 wt % Device 23 Formula (1-48) BAlq 2:8 DMQA 15 wt %  Device 24 Formula (1-50) TPBi 3:7 TMDBQA 15 wt %  Device 25 Formula (1-51) Bphen 4:5 DPAVB 5 wt % Device 26 Formula (1-55) Bphen 5:4 Rubrene 5 wt % Device 27 Formula (1-60) TPBi 6:3 DCJTB 5 wt % Device 28 Formula (1-65) BAlq 7:2 DBQA 15 wt %  Device 29 Formula (1-78) TmPyPB 8:1 DCM2 5 wt % Device 30 Formula (1-86) Bphen 9:1 Rubrene 5 wt %

Embodiments 31-45

(49) Devices 31-45 of these embodiments have the following structure:

(50) glass/ITO/TADF:hole transport type material:phosphorescence material/cathode

(51) Wherein, the respective materials and mass ratios of the TADF, the hole transport type material and the phosphorescence material are listed in Table 4.

(52) Wherein the doping concentration of the phosphorescence material refers to the ratio that the phosphorescence material accounts for in the total mass of the light emitting layer, that is, the phosphorescence material doping concentration=the phosphorescence material mass/(the phosphorescence material mass+the TADF mass+the hole transport type material mass)*100%.

(53) The preparation method of the devices 31-45 comprises the step of evaporation coating an anode layer (ITO), a light emitting layer and a cathode layer (cathode) in sequence on a substrate by using an open mask, wherein the light emitting layer is prepared by co-evaporation coating of a host material (TADF:hole transport type material) and a phosphorescence material.

(54) TABLE-US-00006 TABLE 4 doping concentration of Hole the transport phosphorescence phosphorescence TADF type material Mass ratio material material Device 31 Formula (1-32) NPB 1:9 Ir(ppy).sub.3 30 wt % Device 32 Formula (1-33) TCTA 2:8 Ir(ppy).sub.2(acac) 15 wt % Device 33 Formula (1-34) CBP 3:7 FIrPic  5 wt % Device 34 Formula (1-56) mCP 4:5 Ir(2-phq).sub.2(acac) 15 wt % Device 35 Formula (1-36) TPD 5:4 Ir(ppy).sub.2(acac) 30 wt % Device 36 Formula (1-37) TAPC 6:3 Ir(btpy).sub.3 20 wt % Device 37 Formula (1-38) CBP 7:2 Be(pp).sub.2  5 wt % Device 38 Formula (1-39) mCP 8:1 Ir(piq).sub.2(acac) 15 wt % Device 39 Formula (1-41) mCP 9:1 Ir(ppy).sub.3 30 wt % Device 40 Formula (1-42) NPB 1:9 FIrPic  5 wt % Device 41 Formula (1-43) CBP 2:8 Ir(piq).sub.2(acac) 15 wt % Device 42 Formula (1-44) TAPC 3:7 Ir(ppy).sub.2(acac) 15 wt % Device 43 Formula (1-46) NPB 4:5 FIr6 10 wt % Device 44 Formula (1-47) TCTA 5:4 Ir(piq).sub.2(acac) 30 wt % Device 45 Formula (1-49) CBP 6:3 Be(pp).sub.2  5 wt %

Embodiments 46-60

(55) Devices 46-60 of these embodiments have the following structure:

(56) glass/ITO/TADF:electron transport type material:phosphorescence material/cathode

(57) Wherein, the respective materials and mass ratios of the TADF, the electron transport type material and the phosphorescence material are listed in Table 5.

(58) Wherein the doping concentration of the phosphorescence material refers to the ratio that the phosphorescence material accounts for in the total mass of the light emitting layer, that is, the phosphorescence material doping concentration=the phosphorescence material mass/(the phosphorescence material mass+the TADF mass+the electron transport type material mass)*100%.

(59) The preparation method of the devices 46-60 comprises the step of evaporation coating an anode layer (ITO), a light emitting layer and a cathode layer (cathode) in sequence on a substrate by using an open mask, wherein the light emitting layer is prepared by co-evaporation coating of a host material (TADF:electron transport type material) and a phosphorescence material.

(60) TABLE-US-00007 TABLE 5 doping concentration of Electron the transport phosphorescence phosphorescence TADF type material Mass ratio material material Device 46 Formula (1-52) BAlq 1:9 Ir(ppy).sub.3 30 wt % Device 47 Formula (1-53) TPBi 2:8 Ir(ppy).sub.2(acac) 15 wt % Device 48 Formula (1-54) Bphen 3:7 FIrPic  5 wt % Device 49 Formula (1-57) Bphen 4:5 Ir(2-phq).sub.2(acac) 15 wt % Device 50 Formula (1-58) Alq3 5:4 Ir(ppy).sub.2(acac) 30 wt % Device 51 Formula (1-59) Alq.sub.3 6:3 Ir(btpy).sub.3 20 wt % Device 52 Formula (1-72) Bphen 7:2 Be(pp).sub.2  5 wt % Device 53 Formula (1-76) BCP 8:1 Ir(piq).sub.2(acac) 15 wt % Device 54 Formula (1-80) TmPyPB 9:1 Ir(ppy).sub.3 30 wt % Device 55 Formula (1-82) TPBi 1:9 FIrPic  5 wt % Device 56 Formula (1-83) BAlq 2:8 Ir(piq).sub.2(acac) 15 wt % Device 57 Formula (1-85) TPBi 3:7 Ir(ppy).sub.2(acac) 15 wt % Device 58 Formula (1-63) BCP 4:5 FIr6 10 wt % Device 59 Formula (1-68) Bphen 5:4 Ir(piq).sub.2(acac) 30 wt % Device 60 Formula (1-66) BCP 6:3 Be(pp).sub.2  5 wt %

Embodiments 61-74

(61) Devices 61-74 of these embodiments have the following structure:

(62) glass/ITO/TADF:dye/cathode

(63) Wherein, the materials and mass ratios of the dye as in the (TADF:dye) are listed in Table 6.

(64) Wherein the dye is a fluorescence material and/or a phosphorescence material, the doping concentration of the dye refers to the ratio that the dye accounts for in the total mass of the light emitting layer, that is, the dye doping concentration=the dye mass/(the dye mass+the TADF mass)*100%.

(65) The preparation method of the devices 61-74 comprises the step of evaporation coating an anode layer (ITO), a light emitting layer and a cathode layer (cathode) in sequence on a substrate by using an open mask, wherein the light emitting layer is prepared by co-evaporation coating of a host material TADF and a dye.

(66) TABLE-US-00008 TABLE 6 dye doping concen- TADF Dye Dye name tration Device 61 Formula (1-87) fluorescence TMDBQA 10 wt %  Device 62 Formula (1-88) fluorescence DMQA 5 wt % Device 63 Formula (1-89) fluorescence DPAVBi 5 wt % Device 64 Formula (1-90) fluorescence BCzVBi 5 wt % Device 65 Formula (1-91) fluorescence DCJT 5 wt % Device 66 Formula (1-92) fluorescence DCJTB 5 wt % Device 67 Formula (1-93) fluorescence Rubrene 5 wt % Device 68 Formula (1-94) phospho- Ir(ppy).sub.3 30 wt %  rescence Device 69 Formula (1-95) phospho- Ir(ppy).sub.2(acac) 15 wt %  rescence Device 70 Formula (1-96) phospho- FIrPic 5 wt % rescence Device 71 Formula (1-97) phospho- Ir(2-phq).sub.2(acac) 15 wt %  rescence Device 72 Formula (1-98) phospho- Ir(ppy).sub.2 (acac) 30 wt %  rescence Device 73 Formula (1-99) phospho- Ir(btpy).sub.3 20 wt %  rescence Device 74 Formula phospho- Be(pp).sub.2 5 wt % (1-100) rescence

(67) Test results of performance of some devices of the above-mentioned Devices 4-74 are listed as follows:

(68) TABLE-US-00009 Luminous External Brightness efficiency quantum Service life T.sub.90 Device (cd/m.sup.2) (cd/A) efficiency (%) (hrs) Device 4 5000 20 17 520 Device 8 5000 17 16 498 Device 10 1000 10 4 163 Device 12 1000 9 3 150 Device 15 1000 6 5 155 Device 18 1000 8 5 164 Device 20 1000 8 5 160 Device 24 5000 20 19 392 Device 26 5000 16 17 511 Device 30 5000 17 17 509 Device 35 5000 60 16 398 Device 40 1000 4 6 89 Device 48 1000 4 5 79 Device 55 1000 6 5 80 Device 62 5000 19 17 355 Device 68 5000 57 15 472 Device 70 1000 5 6 74 Device 72 5000 52 14 394 Device 74 1000 7 13 88

(69) Embodiments of synthesis of the compound of formula (1-85) to (1-98):

Embodiment 75

(70) The synthesis method of the compound of formula (1-85) is as follows: in a nitrogen atmosphere, 1 mol potassium tert-butoxide is dissolved in 20 mL DML with stirring for 1 hour, then a DML solution containing 1 mol carbazole is added dropwise therein, after that the resultant solution is stirred for 1 hour; then, a DMF solution containing 0.2 mol 2,3,4,5,6-pentafluorobenzonitrile is added dropwise therein, after that the resultant solution is stirred for 5 hours; then, the reacted liquid is poured into water, and solid is obtained after filtration and separated by using a chromatographic column. Thereby the compound of formula (1-85) is produced, with a yield rate of 90%.

(71) Mass spectrum: 929.

(72) Element analysis: C: 86.60, H: 4.35, N: 9.05.

Embodiment 76

(73) In the synthesis method of the compound of formula (1-86), the reactant carbazole is replaced by tert-butyl carbazole, and a synthesis process similar to that of Embodiment 75 is carried out to produce the compound of formula (1-86), with a yield rate of 91%.

(74) Mass spectrum: 1490.

(75) Element analysis: C: 86.20, H: 8.16, N: 5.64.

Embodiment 77

(76) In the synthesis method of the compound of formula (1-87), the reactant carbazole is replaced by phenyl carbazole, and a synthesis process similar to that of Embodiment 75 is carried out to produce the compound of formula (1-87), with a yield rate of 91%.

(77) Mass spectrum: 1689.

(78) Element analysis: C: 90.20, H: 4.83, N: 4.97.

Embodiment 78

(79) The synthesis method of the compound of formula (1-88) is as follows: in a nitrogen atmosphere, 1 mol potassium tert-butoxide is dissolved in 20 mL DML with stirring for 1 hour, then a DML solution containing 1 mol carbazole is added dropwise therein, after that the resultant solution is stirred for 1 hour; then, a DMF solution containing 0.25 mol 2,3,5,6-tetrafluorobenzonitrile is added dropwise therein, after that the resultant solution is stirred for 5 hours; then, the reacted liquid is poured into water, and solid is obtained after filtration and separated by using a chromatographic column. Thereby the compound of formula (1-88) is produced, with a yield rate of 90%.

(80) Mass spectrum: 763.

(81) Element analysis: C: 86.47, H: 4.36, N: 9.17.

Embodiment 79

(82) In the synthesis method of the compound of formula (1-89), the reactant carbazole is replaced by tert-butyl carbazole, and a synthesis process similar to that of Embodiment 78 is carried out to produce the compound of formula (1-89), with a yield rate of 91%.

(83) Mass spectrum: 1212.

(84) Element analysis: C: 86.15, H: 8.07, N: 5.77.

Embodiment 80

(85) In the synthesis method of the compound of formula (1-90), the reactant carbazole is replaced by methyl carbazole, and a synthesis process similar to that of Embodiment 78 is carried out to produce the compound of formula (1-90), with a yield rate of 91%.

(86) Mass spectrum: 876.

(87) Element analysis: C: 86.36, H: 5.65, N: 7.99.

Embodiment 81

(88) In the synthesis method of the compound of formula (1-91), the reactant carbazole is replaced by phenyl carbazole, and a synthesis process similar to that of Embodiment 78 is carried out to produce the compound of formula (1-91), with a yield rate of 91%.

(89) Mass spectrum: 1372.

(90) Element analysis: C: 90.10, H: 4.79, N: 5.10.

Embodiment 82

(91) In the synthesis method of the compound of formula (1-92), the reactant carbazole is replaced by methoxyl carbazole, and a synthesis process similar to that of Embodiment 78 is carried out to produce the compound of formula (1-92), with a yield rate of 91%.

(92) Mass spectrum: 1004.

(93) Element analysis: C: 75.35, H: 4.93, N: 6.97.

Embodiment 83

(94) The synthesis method of the compound of formula (1-93) is as follows: in a nitrogen atmosphere, 1 mol potassium tert-butoxide is dissolved in 20 mL DML with stirring for 1 hour, then a DML solution containing 1 mol methoxyl carbazole is added dropwise therein, after that the resultant solution is stirred for 1 hour; then, a DMF solution containing 0.33 mol 2,4,6-trifluorobenzonitrile is added dropwise therein, after that the resultant solution is stirred for 5 hours; then, the reacted liquid is poured into water, and solid is obtained after filtration and separated by using a chromatographic column. Thereby the compound of formula (1-93) is produced, with a yield rate of 90%.

(95) Mass spectrum: 778.

(96) Element analysis: C: 75.55, H: 4.93, N: 7.19.

Embodiment 84

(97) In the synthesis method of the compound of formula (1-94), the reactant carbazole is replaced by tert-butyl carbazole, and a synthesis process similar to that of Embodiment 83 is carried out to produce the compound of formula (1-94), with a yield rate of 91%.

(98) Mass spectrum: 935.

(99) Element analysis: C: 86.00, H: 7.81, N: 5.99.

Embodiment 85

(100) In the synthesis method of the compound of formula (1-95), the reactant carbazole is replaced by phenoxazine, and a synthesis process similar to that of Embodiment 83 is carried out to produce the compound of formula (1-95), with a yield rate of 91%.

(101) Mass spectrum: 829.

(102) Element analysis: C: 79.79, H: 4.00, N: 8.48.

Embodiment 86

(103) In the synthesis method of the compound of formula (1-96), the reactant carbazole is replaced by phenothiazine, and a synthesis process similar to that of Embodiment 83 is carried out to produce the compound of formula (1-96), with a yield rate of 91%.

(104) Mass spectrum: 892.

(105) Element analysis: C: 74.05, H: 3.70, N: 7.88.

Embodiment 87

(106) In the synthesis method of the compound of formula (1-97), the reactant carbazole is replaced by acridine, and a synthesis process similar to that of Embodiment 83 is carried out to produce the compound of formula (1-97), with a yield rate of 91%.

(107) Mass spectrum: 932.

(108) Element analysis: C: 86.32, H: 6.15, N: 7.52.

Embodiment 88

(109) In the synthesis method of the compound of formula (1-98), the reactant carbazole is replaced by phenazine, and a synthesis process similar to that of Embodiment 83 is carried out to produce the compound of formula (1-98), with a yield rate of 91%.

(110) Mass spectrum: 880.

(111) Element analysis: C: 80.50, H: 5.17, N: 14.32.

(112) Apparently, the aforementioned embodiments are merely examples illustrated for clearly describing the present invention, rather than limiting the implementation ways thereof. For those skilled in the art, various changes and modifications in other different forms can be made on the basis of the aforementioned description. It is unnecessary and impossible to exhaustively list all the implementation ways herein. However, any obvious changes or modifications derived from the aforementioned description are intended to be embraced within the protection scope of the present invention.