Photoelectric device, preparation method thereof and display device

Abstract

The invention discloses a photoelectric device and a preparation method thereof and a display device, the photoelectric device comprises an anode, a hole function layer, a light-emitting layer and a cathode, the hole function layer comprises a hole transport layer, and a first material is arranged in the hole transport layer and / or one side, facing the light-emitting layer, of the hole transport layer; wherein the absolute value of the difference between the LUMO energy level of the first material and the valence band energy level of the material of the light-emitting layer is greater than or equal to 1.0 eV. The problem that the brightness of a photoelectric device rises in different amplitudes in the service life testing process is solved.

Description

Technical Field

[0001] The present application relates to the field of optoelectronic devices, and in particular to an optoelectronic device, a preparation method thereof, and a display device. Background Art

[0002] Optoelectronic devices refer to devices made based on the photoelectric effect, which may be organic light-emitting diodes (OLEDs), quantum dot light-emitting diodes (QLEDs), detectors, etc.

[0003] The structure of existing optoelectronic devices generally includes a cathode, a light-emitting layer, a hole transport layer, and an anode. As device research continues to deepen, more and more devices have been found to have different degrees of brightness increase during life tests, and only begin to decay after reaching the highest point, which affects the quality repeatability of the device and is not conducive to its industrial development. Summary of the invention

[0004] In view of this, the present application provides an optoelectronic device, a method for preparing the same, and a display device, aiming to improve the problem of different increases in brightness of the optoelectronic device during a life test.

[0005] The embodiment of the present application is implemented as follows:

[0006] In a first aspect, the present application provides an optoelectronic device, comprising an anode, a hole functional layer, a light-emitting layer and a cathode, wherein the hole functional layer comprises a hole transport layer, and a first material is disposed inside the hole transport layer and / or on a side of the hole transport layer facing the light-emitting layer;

[0007] The absolute value of the difference between the LUMO energy level of the first material and the valence band energy level of the material of the light-emitting layer is greater than or equal to 1.0 eV.

[0008] Optionally, in some embodiments of the present application, the absolute value of the difference between the LUMO energy level of the first material and the valence band energy level of the material of the light-emitting layer is greater than or equal to 1.0 eV and less than or equal to 2.0 eV.

[0009] Optionally, in some embodiments of the present application, the hole mobility of the first material is greater than or equal to 1×10 - 6 cm 2 / (V·s).

[0010] Optionally, in some embodiments of the present application, the hole mobility of the first material is greater than or equal to 1×10 - 6 cm 2 / (V·s), and less than or equal to 1×10 -2 cm 2 / (V·s).

[0011] Optionally, in some embodiments of the present application, the first material includes one or more of Spiro-OMeTAD, Spiro-TPD, TAPC, TPDI, TCTA, and PVK.

[0012] Optionally, in some embodiments of the present application, in the hole functional layer, the mass ratio of the first material to the material of the hole transport layer is 0.1 to 1:1; and / or,

[0013] The hole transport layer includes materials such as 4,4'-N,N'-dicarbazolyl-biphenyl, N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, tris(3-methylphenylphenylamino)-triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))] and poly(4-butylphenyl-diphenylamine) , polyaniline, polypyrrole, poly(p-)phenylene vinylene, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], copper phthalocyanine, aromatic tertiary amines, polynuclear aromatic tertiary amines, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compounds, N,N,N',N'-tetraarylbenzidine, PEDOT:PSS and its derivatives, poly(N-vinylcarbazole) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-di(naphthalene-1-yl)-N,N'-diphenylbenzidine, spiro NPB and one or more thereof.

[0014] Optionally, in some embodiments of the present application, the first material disposed on the side of the hole transport layer facing the light-emitting layer is formed into a film layer, and the thickness of the film layer is 20 to 120 nm.

[0015] Optionally, in some embodiments of the present application, the photoelectric device further comprises a hole injection layer, wherein the hole injection layer is disposed between the hole functional layer and the anode; the material of the hole injection layer comprises poly(ethylenedioxythiophene): polystyrene sulfonate, poly(9,9-dioctyl-fluorene-co-N-(4-butylphenyl)-diphenylamine), polyarylamine, poly(N-vinylcarbazole), polyaniline, polypyrrole, N,N,N',N'-tetrakis(4-methoxyphenyl)-benzidine, 4-bis[N-(1-naphthyl)-N-phenyl-amino ] biphenyl, 4,4',4"-tri[phenyl(m-tolyl)amino]triphenylamine, 4,4',4"-tri(N-carbazolyl)-triphenylamine, 1,1-bis[(di-4-tolylamino)phenylcyclohexane, 4,4',4"-tri(diphenylamino)triphenylamine doped with tetrafluoro-tetracyano-quinodimethane, p-doped phthalocyanine, F4-TCNQ doped N,N'-diphenyl-N,N'-di(1-naphthyl)-1,1'-biphenyl-4,4"-diamine, hexaazatriphenylene-capronitrile or more thereof; and / or,

[0016] The photoelectric device further comprises an electron transport layer disposed between the light-emitting layer and the cathode, wherein the material of the electron transport layer comprises one or more of metal oxides and doped metal oxides; the metal oxide comprises one or more of ZnO, TiO2, SnO2, ZrO, Al2O3, WO3, HfO3, Ta2O3, ZrSiO4, BaTiO3, and BaZrO3; the metal oxide in the doped metal oxide comprises a plurality of ZnO, TiO2, SnO2, ZrO, Al2O3, WO3, HfO3, Ta2O3, ZrSiO4, BaTiO3, and BaZrO3, and the doping element comprises one or more of Al, Mg, Li, In, Ga, Cd, Cs, and Cu; and / or,

[0017] The anode and the cathode are independently selected from a doped metal oxide particle electrode, a composite electrode of metal and metal oxide, a graphene electrode, a carbon nanotube electrode, a metal electrode or an alloy electrode; the material of the doped metal oxide particle electrode is selected from one or more of indium-doped tin oxide, fluorine-doped tin oxide, antimony-doped tin oxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, indium-doped zinc oxide, magnesium-doped zinc oxide and aluminum-doped magnesium oxide; the composite electrode of metal and metal oxide is selected from AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, TiO2 / Ag / TiO2, TiO2 / Al / TiO2, ZnS / Ag / ZnS, ZnS / Al / ZnS; the material of the metal electrode is selected from one or more of Ag, Al, Cu, Mo, Au, Pt, Si, Ca, Mg and Ba; and / or,

[0018] The material of the light-emitting layer includes at least one of single structure quantum dots, core-shell structure quantum dots and perovskite semiconductor materials; the material of the single structure quantum dots, the core material of the core-shell structure quantum dots and the shell material of the core-shell structure quantum dots are respectively selected from at least one of II-VI group compounds, IV-VI group compounds, III-V group compounds and I-III-VI group compounds; the II-VI group compounds are selected from CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe , HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe; the IV-VI group compound is selected from SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, Pb At least one of SeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe; the III-V group compound is selected from GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlN At least one of As, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs and InAlPSb; the I-III-VI group compound is selected from at least one of CuInS2, CuInSe2 and AgInS2; the perovskite semiconductor material is selected from doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors; the inorganic perovskite semiconductor has a general structural formula of AMX3, wherein A is Cs + ion, M is a divalent metal cation selected from Pb 2+ Sn 2+ , Cu 2+ 、Ni2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ At least one of, X is a halogen anion selected from Cl - Br - ,I - At least one of the following; the general structural formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, wherein B is an organic amine cation selected from CH3(CH2) n-2 NH3 + or [NH3(CH2) n NH3] 2+ , where n≥2, M is a divalent metal cation selected from Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ At least one of, X is a halogen anion selected from Cl - Br - ,I - At least one of .

[0019] In a second aspect, the present application also proposes a method for preparing a photoelectric device, comprising the following steps:

[0020] providing a first electrode;

[0021] Disposing a plurality of film layers on one side of the first electrode;

[0022] Disposing a second electrode on a side of the plurality of film layers away from the first electrode to obtain a photoelectric device;

[0023] Wherein, the first electrode includes one of an anode and a cathode, the second electrode includes the other of the anode and the cathode, the plurality of film layers include a light-emitting layer and a hole functional layer, and the light-emitting layer is disposed between the hole functional layer and the cathode;

[0024] The preparation of the hole functional layer includes: providing a hole transport material and a first material; depositing the hole transport material and the first material to form a hole functional layer;

[0025] The absolute value of the difference between the LUMO energy level of the first material and the valence band energy level of the material of the light-emitting layer is greater than or equal to 1.0 eV.

[0026] Optionally, in some embodiments of the present application, the first material includes one or more of Spiro-OMeTAD, Spiro-TPD, TAPC, TPDI, TCTA, and PVK; and / or,

[0027] The mass ratio of the first material to the hole transport material is 0.1 to 1:1.

[0028] Optionally, in some embodiments of the present application, a hole transport material and a first material are provided; and the step of depositing the hole transport material and the first material to form a hole functional layer includes:

[0029] Mixing a hole transport material, a first material and a first solvent to obtain a mixed solution; depositing the mixed solution and then performing a first annealing treatment to obtain a hole functional layer; or,

[0030] Dispersing a first material in a second solvent to obtain a first material solution, depositing the first material solution, and then performing a second annealing treatment to obtain a first film layer; dispersing a hole transport material in a second solvent to obtain a hole transport solution, depositing the hole transport solution, and then performing a third annealing treatment to obtain a second film layer, wherein the first film layer and the second film layer together constitute a hole functional layer; or

[0031] The first material includes a first sub-material and a second sub-material; the first sub-material is dispersed in a fourth solvent to obtain a sub-material solution, the first sub-material solution is deposited, and then a fourth annealing treatment is performed to obtain a third film layer; the hole transport material and the second sub-material are dispersed in a fifth solvent to obtain a hole mixed solution, the hole mixed solution is deposited, and then a fifth annealing treatment is performed to obtain a fourth film layer, and the third film layer and the fourth film layer together constitute a hole functional layer.

[0032] Optionally, in some embodiments of the present application, the first solvent includes one or more of chlorobenzene, toluene, and xylene; and / or,

[0033] The temperature of the first annealing treatment is 150-200° C.; and / or,

[0034] The first annealing treatment lasts for 10 to 120 minutes; and / or,

[0035] The second solvent includes one or more of chlorobenzene, toluene and xylene; and / or,

[0036] The temperature of the second annealing treatment is 150-250° C.; and / or,

[0037] The second annealing treatment lasts for 10 to 120 minutes; and / or,

[0038] The third solvent includes one or more of chlorobenzene, toluene and xylene; and / or,

[0039] The temperature of the third annealing treatment is 150-200° C.; and / or,

[0040] The third annealing treatment lasts for 10 to 120 minutes; and / or,

[0041] The fourth solvent includes one or more of chlorobenzene, toluene, and xylene; and / or,

[0042] The temperature of the fourth annealing treatment is 150-250° C.; and / or,

[0043] The fourth annealing treatment lasts for 10 to 120 minutes; and / or,

[0044] The fifth solvent includes one or more of chlorobenzene, toluene, and xylene; and / or,

[0045] The temperature of the fifth annealing treatment is 150-200° C.; and / or,

[0046] The fifth annealing treatment takes 10 to 120 minutes.

[0047] In a third aspect, the present application further proposes a display device, which includes the optoelectronic device as described above, or includes the optoelectronic device manufactured by the preparation method as described above.

[0048] In the technical solution provided in the present application, a first material is arranged inside the hole transport layer and / or on the side of the hole transport layer facing the light-emitting layer. The first material can block the leakage of electrons into the hole transport layer, inhibit the formation of excitons in the hole transport layer, and reduce the probability of their transfer from the hole transport layer to the light-emitting layer, thereby improving the problem of increased brightness of the device during the life test, helping to improve the repeatability of the device, and facilitating its industrialization. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0050] Figure 1 is a schematic structural diagram of an optoelectronic device proposed in one embodiment of the present application;

[0051] Figure 2 is a schematic structural diagram of a photoelectric device proposed in another embodiment of the present application;

[0052] Figure 3 It is a schematic diagram of a process for preparing a photoelectric device proposed in an embodiment of the present application;

[0053] Reference numerals:

[0054] 100 - photoelectric device; 10 - anode; 20 - light-emitting layer; 30 - electron transport layer; 40 - cathode; 50 - first film layer; 60 - hole injection layer; 70 - second film layer; 80 - hole functional layer. DETAILED DESCRIPTION

[0055] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work belong to the scope of protection of the present application. In addition, it should be understood that the specific implementation methods described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0056] In this application, unless otherwise specified, the directional words used, such as "upper" and "lower", refer specifically to the directions of the drawings in the accompanying drawings. In addition, in the description of the specification of this application, the term "including" means "including but not limited to".

[0057] Various embodiments of the present application may be presented in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be understood as a rigid limitation on the scope of the present application; therefore, the range description should be considered to have specifically disclosed all possible sub-ranges and single numerical values ​​within the range. For example, the range description from 1 to 6 should be considered to have specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the range, such as 1, 2, 3, 4, 5 and 6, which apply regardless of the range. In addition, whenever a numerical range is indicated herein, it is meant to include any cited number (fractional or integer) within the indicated range.

[0058] In this application, "and / or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural.

[0059] In the present application, "at least one" means one or more, and "plurality" means two or more. "At least one", "at least one of the following" or similar expressions refer to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can all mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, c can be single or multiple, respectively.

[0060] In a first aspect, the present application embodiment provides an optoelectronic device 100, see Figure 1 and 2 The photoelectric device 100 includes an anode 10, a hole functional layer 80, a light-emitting layer 20 and a cathode 40, wherein the hole functional layer 80 includes a hole transport layer, and a first material is arranged inside the hole transport layer and / or on the side of the hole transport layer facing the light-emitting layer 20; wherein the absolute value of the difference between the LUMO energy level of the first material and the valence band energy level (CB) of the material of the light-emitting layer 20 is greater than or equal to 1.0 eV.

[0061] In the technical solution provided in the present application, a first material is arranged inside the hole transport layer and / or on the side of the hole transport layer facing the light-emitting layer 20, and the difference between the LUMO energy level of the first material and the valence band energy level (CB) of the material of the light-emitting layer 20 |ΔE LUMO,HTL-CB,QD ∣ is greater than or equal to 1.0eV, for example, it can be 1.0eV, 1.1eV, 1.2eV, 1.3eV, 1.4eV, 1.5eV, 1.6eV, 1.7eV, 1.8eV, 1.9eV, 2.0eV, 2.1eV, 2.2eV, 2.3eV, 2.4eV, 2.4eV or above, or a value between any two of the above values, etc. Such a first material can block the leakage of electrons into the hole transport layer, inhibit the formation of excitons in the hole transport layer, and reduce the probability of their transfer from the hole transport layer to the light-emitting layer 20, thereby improving the problem of brightness increase during the life test of the device, helping to improve the repeatability of the device, and facilitating its industrialization.

[0062] In some embodiments, the anode 10 may be an anode 10 known in the art for use in a photoelectric device 100, for example, may be selected from but not limited to a doped metal oxide particle electrode, a composite electrode of a metal and a metal oxide, a graphene electrode, a carbon nanotube electrode, a metal electrode or an alloy electrode, the material of the doped metal oxide particle electrode is selected from one or more of indium-doped tin oxide, fluorine-doped tin oxide, antimony-doped tin oxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, indium-doped zinc oxide, magnesium-doped zinc oxide and aluminum-doped magnesium oxide, the composite electrode of a metal and a metal oxide is selected from AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, TiO2 / Ag / TiO2, TiO2 / Al / TiO2, ZnS / Ag / ZnS, ZnS / Al / ZnS, the material of the metal electrode is selected from one or more of Ag, Al, Cu, Mo, Au, Pt, Si, Ca, Mg and Ba. The thickness of the anode 10 may be 20-200 nm.

[0063] The cathode 40 can be a cathode 40 for the optoelectronic device 100 known in the art, for example, can be selected from but not limited to a doped metal oxide particle electrode, a composite electrode of metal and metal oxide, a graphene electrode, a carbon nanotube electrode, a metal electrode or an alloy electrode, the material of the doped metal oxide particle electrode is selected from one or more of indium-doped tin oxide, fluorine-doped tin oxide, antimony-doped tin oxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, indium-doped zinc oxide, magnesium-doped zinc oxide and aluminum-doped magnesium oxide, the composite electrode of metal and metal oxide is selected from AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, TiO2 / Ag / TiO2, TiO2 / Al / TiO2, ZnS / Ag / ZnS, ZnS / Al / ZnS, and the material of the metal electrode is selected from one or more of Ag, Al, Cu, Mo, Au, Pt, Si, Ca, Mg and Ba. The thickness of the cathode 40 may be 20-200 nm.

[0064] In some embodiments, the material of the light-emitting layer 20 is a quantum dot material known in the art for the light-emitting layer 20 of the optoelectronic device 100, for example, it can be selected from but not limited to at least one of a single structure quantum dot, a core-shell structure quantum dot and a perovskite semiconductor material; the material of the single structure quantum dot, the core material of the core-shell structure quantum dot and the shell material of the core-shell structure quantum dot are respectively selected from at least one of a II-VI group compound, a IV-VI group compound, a III-V group compound and a I-III-VI group compound; the II-VI group compound is selected from CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, Z nO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHg At least one of Te, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe; the IV-VI The III-V group compound is selected from at least one of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe; the III-V group compound is selected from at least one of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlN P, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs and InAlPSb; the I-III-VI group compound is selected from at least one of CuInS2, CuInSe2 and AgInS2.

[0065] As an example, the core-shell structured quantum dots may be selected from but not limited to at least one of CdZnSe / CdZnSe / ZnSe / CdZnS / ZnS, CdZnSe / CdZnSe / CdZnS / ZnS CdSe / CdSeS / CdS, InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnSeS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdSe / CdZnSeS / ZnS and InP / ZnSe / ZnS.

[0066] It should be noted that, for the material of the aforementioned single structure quantum dot, or the material of the core of the core-shell structure quantum dot, or the material of the shell of the core-shell structure quantum dot, the chemical formula provided only indicates the elemental composition, but does not indicate the content of each element. For example, CdZnSe only indicates that it is composed of three elements, Cd, Zn and Se. If the content of each element is indicated, it corresponds to Cd x Zn 1-x Se,0 <x<1。

[0067] The perovskite semiconductor material may be selected from but not limited to doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors; the inorganic perovskite semiconductor has a general structural formula of AMX3, wherein A is Cs + ion, M is a divalent metal cation selected from Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ At least one of, X is a halogen anion selected from Cl - Br - ,I - At least one of the following; the general structural formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, wherein B is an organic amine cation selected from CH3(CH2) n-2 NH3 + or [NH3(CH2) n NH3] 2+ , where n≥2, M is a divalent metal cation selected from Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ At least one of, X is a halogen anion selected from Cl - Br - ,I - At least one of .

[0068] In some embodiments, the thickness of the light emitting layer 20 may be 10 to 180 nm, for example, 10 nm, 20 nm, 30 nm, 40 nm, 50 nm, 60 nm, 70 nm, 80 nm, 90 nm, 100 nm, 120 nm, 150 nm, 180 nm, and values ​​between any two of the above values. In other embodiments, the thickness of the light emitting layer 20 may be 20 to 50 nm.

[0069] Since the energy level difference between the LUMO energy level of the hole transport material and the valence band (CB) of the quantum dot light-emitting layer is relatively small, excessive electrons will be injected into the hole transport material during the operation of the device, so that some electrons and holes form excitons in the TFB. As an inorganic nanomaterial, there is a special inorganic-organic contact interface between the quantum dot and the organic hole transport material, which changes the electrical properties of the device during operation, so that some excitons formed in the hole transport material during the operation of the QLED device may be transferred to the quantum dot light-emitting layer, resulting in the problem of brightness increase. Since the brightness increase is uncontrollable, the repeatability of the device is affected, which significantly restricts the path of industrialization. In order to eliminate the brightness increase problem of the QLED device during the operation process / life test process, the embodiment of the present application is doped with a first material inside the hole transport layer of the QLED, and / or a film layer containing the first material is provided between the hole transport layer and the light-emitting layer 20, and the first material is used to effectively inhibit the formation of excitons on the hole side and the migration from the hole side to the light-emitting layer 20, thereby improving the brightness increase problem during the operation process / life test process.

[0070] In some embodiments, the absolute value of the difference between the LUMO energy level of the first material and the valence band energy level of the material of the light-emitting layer 20 is greater than or equal to 1.0 eV and less than or equal to 2.0 eV.

[0071] In some embodiments, the hole mobility of the first material is greater than or equal to 1×10 -6 cm 2 / (V·s). For example, 1×10 -6 cm 2 / (V·s),2×10 -6 cm 2 / (V·s),5×10 -6 cm 2 / (V·s),10 -5 cm 2 / (V·s),10 -4 cm 2 / (V·s),10 -3 cm 2 / (V·s),10 -2 cm 2 / (V·s),10 -2 cm 2 / (V·s) or above, or a value between any two of the above values, etc., which helps to promote hole injection. In some other embodiments, the hole mobility of the first material is greater than or equal to 1×10 -6 cm 2 / (V·s), and less than or equal to 1×10 -2 cm 2 / (V·s). In some other embodiments, the hole mobility of the first material is greater than or equal to 1×10 -4 cm 2 / (V·s), and less than or equal to 1×10 -2 cm 2 / (V·s).

[0072] In some specific embodiments, the first material includes one or more of Spiro-OMeTAD, Spiro-TPD, TAPC, TPDI, TCTA, and PVK. The specific information of these materials is as follows:

[0073] The LUMO level of Spiro-OMeTAD is -2.15 eV and the mobility is 4.2×10 -3 cm 2 / (V·s), see J.Mater.Chem.A, 2018, 6, 10057-10063 for details;

[0074] The LUMO level of Spiro-TPD is -2.1 eV and the mobility is 1.0×10 -3 cm 2 / (V·s), see Organic Electronics 13(2012)541-544 and Nano Lett.2009,9,2532-2536.

[0075] TAPC, also known as [4-[1-[4-[di(4-methylphenyl)amino]phenyl]cyclohexyl]-N-(3-methylphenyl)-N-(4-methylphenyl)aniline, CAS No. 1174006-36-0, LUMO energy level is -1.8 eV, mobility is 1.0×10 -2 cm 2 / (V·s);

[0076] The LUMO energy level of TPDI is -1.9 eV and the mobility is 6.14×10 -3 cm 2 / (V·s)For details, see Synthetic Metals 180(2013)79–84;

[0077] TCTA, also known as 4,4',4'-tri(N-carbazolyl)-triphenylamine, 4,4',4"-tri(carbazolyl-9-yl)triphenylamine; CAS number is 139092-78-7, LUMO energy level is -2.4eV, mobility is 1×10 -5 cm 2 / (V·s);

[0078] PVK, also known as poly(N-vinyl carbazole), has a CAS number of 25067-59-8, a LUMO energy level of -1.9 eV, and a mobility of 2.5×10 -6 cm 2 / (V·s).

[0079] In some other embodiments, the first material includes one or more of TAPC, TPDI, and PVK. When the first material is selected from these materials, it can match most quantum dot materials and has a wider range of applications.

[0080] In some embodiments, in the hole functional layer 80, the mass ratio of the first material to the material of the hole transport layer is 0.1 to 1:1; for example, it can be 0.1:1, 0.2:1, 0.3:1, 0.4:1, 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, 1:1 and values ​​between any two of the above values. Within this range, it helps to fully exert the inhibitory effect on electron migration and ensure the luminescence performance and life of the device.

[0081] In some embodiments, the first material is disposed on the side of the hole transport layer facing the light emitting layer 20, thereby forming a film layer between the hole transport layer and the light emitting layer 20, which is named as the first material layer. Figure 2, the thickness of the first material layer is 20 to 120 nm; for example, it can be 20 nm, 30 nm, 50 nm, 60 nm, 80 nm, 100 nm, 120 nm, or a value between any two of the above values.

[0082] In some embodiments, the material of the hole transport layer includes 4,4'-N,N'-dicarbazolyl-biphenyl (CBP), N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine (α-NPD), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine (TPD), N,N'-bis(3-methylphenyl)-N,N'-bis( phenyl)-spiro (spiro-TPD), N,N'-di(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine (DNTPD), tris(3-methylphenylphenylamino)-triphenylamine (m-MTDATA), poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))] (TFB), and poly(4-butylphenyl-diphenylamine) (poly-TPD). D), polyaniline, polypyrrole, poly(p-phenylene vinylene) (PPV), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene] (MEH-PPV), poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene] (MOMO-PPV), copper phthalocyanine, aromatic tertiary amines, polynuclear aromatic tertiary amines, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compounds , N,N,N',N'-tetraaryl benzidine, PEDOT:PSS and its derivatives, poly(N-vinyl carbazole) (PVK) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-di(naphthalene-1-yl)-N,N'-diphenylbenzidine (NPB), spiro NPB. The thickness of the hole transport layer can be 30 to 180 nm.

[0083] In some embodiments, the optoelectronic device 100 further includes a hole injection layer 60, and the hole injection layer 60 is disposed between the hole functional layer 80 and the anode 10. The material of the hole injection layer 60 may include, but is not limited to, poly(ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), poly(9,9-dioctyl-fluorene-co-N-(4-butylphenyl)-diphenylamine) (TFB), polyarylamine, poly(N-vinylcarbazole), polyaniline, polypyrrole, N,N,N',N'-tetrakis(4-methoxyphenyl)-benzidine (TPD), 4-bis[N-(1-naphthyl)-N-phenyl-amino]biphenyl (α-NPD), 4,4',4"-tris[phenyl(m-tolyl)amino]triphenylamine (m-MTDATA), 4,4',4 ”-tri(N-carbazolyl)-triphenylamine (TCTA), 1,1-bis[(di-4-tolylamino)phenylcyclohexane (TAPC), 4,4',4"-tri(diphenylamino)triphenylamine (TDATA) doped with tetrafluoro-tetracyano-quinodimethane (F4-TCNQ), p-doped phthalocyanine (e.g., F4-TCNQ-doped zinc phthalocyanine (ZnPc)), F4-TCNQ-doped N,N'-diphenyl-N,N'-di(1-naphthyl)-1,1'-biphenyl-4,4"-diamine (α-NPD), hexaazatriphenylene-capronitrile (HAT-CN) or more. The thickness of the hole injection layer 60 may be 20 to 200 nm.

[0084] In some embodiments, the optoelectronic device 100 further includes an electron transport layer 30 disposed between the light emitting layer 20 and the cathode 40, and the thickness of the electron transport layer 30 may be 20 to 180 nm. The material of the electron transport layer 30 may be a material known in the art for use in optoelectronic devices 100 and having electron transport properties, for example, may include but is not limited to one or more of metal oxides and doped metal oxides; the metal oxides include one or more of ZnO, TiO2, SnO2, ZrO, Al2O3, WO3, HfO3, Ta2O3, ZrSiO4, BaTiO3, and BaZrO3; the metal oxides in the doped metal oxides include multiple of ZnO, TiO2, SnO2, ZrO, Al2O3, WO3, HfO3, Ta2O3, ZrSiO4, BaTiO3, and BaZrO3, and the doping elements include one or more of Al, Mg, Li, In, Ga, Cd, Cs, and Cu.

[0085] It can be understood that the optoelectronic device 100 can be an upright device or an inverted device.

[0086] It is understandable that the optoelectronic device 100 may also be provided with some functional layers conventionally used in optoelectronic devices 100 that help improve the performance of the optoelectronic device 100, such as an electron injection layer, an electron blocking layer, an interface modification layer, etc.

[0087] It can be understood that the material and thickness of each layer of the optoelectronic device 100 can be adjusted according to the actual requirements of the optoelectronic device 100 .

[0088] In a second aspect, the present application also provides a method for preparing an optoelectronic device 100. Figure 3 , the preparation method comprises the following steps:

[0089] S10, providing a first electrode.

[0090] S20, a plurality of film layers are arranged on one side of the first electrode, the plurality of film layers include a light-emitting layer 20 and a hole functional layer 80, the light-emitting layer 20 is arranged between the hole functional layer 80 and the cathode 40; the preparation of the hole functional layer 80 includes: providing a hole transport material and a first material; depositing the hole transport material and the first material to form the hole functional layer 80. The absolute value of the difference between the LUMO energy level of the first material and the valence band energy level of the material of the light-emitting layer 20 is greater than or equal to 1.0 eV.

[0091] S30 , disposing a second electrode on a side of the plurality of film layers away from the first electrode to obtain a photoelectric device 100 .

[0092] The optoelectronic device 100 prepared by the preparation method of this embodiment has a first material arranged inside the hole transport layer and / or on the side of the hole transport layer facing the light-emitting layer 20. The first material can block the leakage of electrons into the hole transport layer, inhibit the formation of excitons in the hole transport layer, and reduce the probability of their transfer from the hole transport layer to the light-emitting layer 20, thereby improving the problem of brightness increase of the device during the life test, helping to improve the repeatability of the device, and facilitating its industrialization.

[0093] It can be understood that, depending on the type of device, the first electrode can be the anode 10 or the cathode 40; for example, when the photoelectric device 100 is an upright device, the first electrode is the anode 10 and the second electrode is the cathode 40; when the photoelectric device 100 is an inverted device, the first electrode is the cathode 40 and the second electrode is the anode 10.

[0094] In some embodiments, the absolute value of the difference between the LUMO energy level of the first material and the valence band energy level of the material of the light-emitting layer 20 is greater than or equal to 1.0 eV and less than or equal to 2.0 eV; the hole mobility of the first material is greater than or equal to 1×10 -6 cm 2 / (V·s), and less than or equal to 1×10 -2 cm 2 / (V·s).

[0095] In some specific embodiments, the first material includes one or more of Spiro-OMeTAD, Spiro-TPD, TAPC, TPDI, TCTA, and PVK.

[0096] In step S20, the hole functional layer 80 can be realized by conventional techniques in the art, such as chemical methods or physical methods. Among them, the chemical method includes chemical vapor deposition, continuous ion layer adsorption and reaction, anodization, electrolytic deposition, and coprecipitation. The physical method includes physical coating and solution method, among which the physical coating method includes: thermal evaporation coating, electron beam evaporation coating, magnetron sputtering, multi-arc ion coating, physical vapor deposition, atomic layer deposition, pulsed laser deposition, etc.; the solution method can be spin coating, printing, inkjet printing, scraping, printing, dip pulling, immersion, spraying, rolling, casting, slit coating, strip coating, etc.

[0097] Taking the solution method as an example, the steps of providing a hole transport material and a first material; depositing the hole transport material and the first material to form the hole functional layer 80 are described in detail.

[0098] In the first embodiment, if Figure 1 As shown, the hole functional layer 80 is obtained by doping the first material into the hole transport layer, and its specific preparation method is: mixing the hole transport material, the first material and the first solvent to obtain a mixed solution; depositing the mixed solution, and then performing a first annealing treatment to obtain the hole functional layer 80.

[0099] Wherein, the first solvent includes one or more of chlorobenzene, toluene and xylene.

[0100] In some embodiments, in the mixed solution, the mass ratio of the first material to the hole transport material is 0.1 to 1:1; the concentration of the hole transport material is 5 to 40 mg / ml, for example, 5 mg / ml, 10 mg / ml, 15 mg / ml, 20 mg / ml, 25 mg / ml, 30 mg / ml, 35 mg / ml, 40 mg / ml and values ​​between any two of the above values.

[0101] In some embodiments, the temperature of the first annealing treatment is 150-200° C.; for example, it can be 150° C., 160° C., 170° C., 180° C., 190° C., 200° C., or a value between any two of the above values.

[0102] In some embodiments, the first annealing treatment time is 10 to 120 minutes; for example, it can be 10 minutes, 20 minutes, 30 minutes, 50 minutes, 60 minutes, 75 minutes, 90 minutes, 120 minutes, and a value between any two of the above values.

[0103] In the second embodiment, if Figure 2 As shown, the first material is disposed on the side of the hole transport layer facing the light-emitting layer 20 to form a first material film layer (named as the first film layer 50), that is, the hole functional layer 80 includes the hole transport layer (named as the second film layer 70) and the first film layer 50. The specific preparation method is: the first material is dispersed in the second solvent to obtain a first material solution, the first material solution is deposited, and then a second annealing treatment is performed to obtain the first film layer 50; the hole transport material is dispersed in the second solvent to obtain a hole transport solution, the hole transport solution is deposited, and then a third annealing treatment is performed to obtain the second film layer 70, and the first film layer 50 and the second film layer 70 together constitute the hole functional layer 80.

[0104] Wherein, the second solvent includes one or more of chlorobenzene, toluene, and xylene; the third solvent includes one or more of chlorobenzene, toluene, and xylene.

[0105] In some embodiments, in the hole transport solution, the concentration of the hole transport material is 5 to 40 mg / ml. The concentration of the first material solution can be adjusted according to the hole transport layer, as long as the mass ratio of the first material to the hole transport material in the prepared hole functional layer 80 is 0.1 to 1:1.

[0106] In some embodiments, the temperature of the second annealing treatment is 150-250°C; for example, it can be 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C and values ​​between any two of the above values.

[0107] In some embodiments, the temperature of the third annealing treatment is 150-200° C.; for example, it can be 150° C., 160° C., 170° C., 180° C., 190° C., 200° C., or a value between any two of the above values.

[0108] In some embodiments, the second annealing treatment time is 10 to 120 minutes; for example, it can be 10 minutes, 20 minutes, 30 minutes, 50 minutes, 60 minutes, 75 minutes, 90 minutes, 120 minutes, and a value between any two of the above values.

[0109] In some embodiments, the third annealing treatment time is 10 to 120 minutes; for example, it can be 10 minutes, 20 minutes, 30 minutes, 50 minutes, 60 minutes, 75 minutes, 90 minutes, 120 minutes, and a value between any two of the above values.

[0110] In the third embodiment, the hole functional layer includes a hole transport layer doped with the first material (named as the fourth film layer) and a film layer made of the first material (the third film layer). The specific preparation method is: the first material is divided into two parts, respectively named as the first sub-material and the second sub-material. The first sub-material is dispersed in the fourth solvent to obtain a sub-material solution, the first sub-material solution is deposited, and then the fourth annealing treatment is performed to obtain the third film layer; the hole transport material and the second sub-material are dispersed in the fifth solvent to obtain a hole mixed solution, the hole mixed solution is deposited, and then the fifth annealing treatment is performed to obtain the fourth film layer, and the third film layer and the fourth film layer together constitute the hole functional layer 80.

[0111] Wherein, the fourth solvent includes one or more of chlorobenzene, toluene, and xylene; the fifth solvent includes one or more of chlorobenzene, toluene, and xylene.

[0112] In some embodiments, the ratio of the first sub-material to the second sub-material is not limited, and it is only necessary to ensure that the total mass of the first sub-material and the second sub-material (i.e., the mass of the first material) in the prepared hole functional layer 80 is 0.1 to 1: 1 with respect to the mass ratio of the hole transport material. In some embodiments, the concentration of the hole transport material in the hole mixed solution is 5 to 40 mg / ml.

[0113] In some embodiments, the temperature of the fourth annealing treatment is 150-250°C; for example, it can be 150°C, 160°C, 170°C, 180°C, 190°C, 200°C, 210°C, 220°C, 230°C, 240°C, 250°C and values ​​between any two of the above values.

[0114] In some embodiments, the temperature of the fifth annealing treatment is 150-200° C.; for example, it can be 150° C., 160° C., 170° C., 180° C., 190° C., 200° C., or a value between any two of the above values.

[0115] In some embodiments, the fourth annealing treatment time is 10 to 120 minutes; for example, it can be 10 minutes, 20 minutes, 30 minutes, 50 minutes, 60 minutes, 75 minutes, 90 minutes, 120 minutes, or a value between any two of the above values.

[0116] In some embodiments, the fifth annealing treatment lasts for 10 to 120 minutes; for example, it can be 10 minutes, 20 minutes, 30 minutes, 50 minutes, 60 minutes, 75 minutes, 90 minutes, 120 minutes, or a value between any two of the above values.

[0117] In other embodiments, the plurality of film layers further include a hole injection layer 60, an electron injection layer, etc. When preparing the optoelectronic device 100, step S20 may specifically prepare the plurality of film layers in sequence according to the film layer stacking sequence of the device design.

[0118] In the method for preparing the optoelectronic device 100, the method for preparing the anode 10, the light-emitting layer 20, the electron transport layer 30, the hole injection layer 60 and the cathode 40 can be implemented by conventional techniques in the art, such as chemical methods or physical methods. In actual application, an appropriate preparation method can be adopted according to the type of the optoelectronic device 100 and the application conditions and requirements.

[0119] In a third aspect, the present application further proposes a display device, which includes the optoelectronic device 100 as described above, or includes the optoelectronic device 100 manufactured by the manufacturing method as described above.

[0120] The display device can be any electronic product with a display function, including but not limited to smart phones, portable phones, tablet computers, personal digital assistants (PDA), portable multimedia players (Portable Multimedia Player), televisions, game consoles, watch-type electronic devices, head-mounted displays, personal computer displays, laptop computers, car navigation systems, car dashboards, digital cameras, portable cameras, external advertising boards, electro-optical panels, medical devices, detection devices, refrigerators, washing machines, etc.

[0121] The technical scheme and technical effects of the present application are described in detail below through specific embodiments and comparative examples. The following embodiments are only some embodiments of the present application and do not specifically limit the present application.

[0122] Example 1

[0123] The preparation method of the QLED device in this embodiment is as follows:

[0124] (1) The patterned ITO glass substrate was cleaned and dried, and then treated with UV-ozone to obtain an anode with a thickness of 100 nm.

[0125] (2) In air, a layer of PEDOT:PSS was spin-coated on the surface of the anode to obtain a hole injection layer with a thickness of 120 nm.

[0126] (3) The substrate was transferred to a glove box filled with nitrogen atmosphere, and a chlorobenzene solution of TFB with a concentration of 30 mg / ml was spin-coated on the surface of the hole injection layer, followed by annealing at 200° C. for 20 min to obtain a hole transport layer with a thickness of 30 nm.

[0127] (4) On the surface of the hole transport layer, a toluene solution of the first material is spin-coated and annealed at 150° C. for 15 min to obtain a first material film layer with a thickness of 90 nm, wherein the first material is TAPC, and the mass ratio of the first material in the first material film layer to the mass ratio of TFB in the hole transport layer is 0.5:1.

[0128] (5) Spin-coat a hexane solution of quantum dot material CdZnSe / ZnSe / CdZnS / ZnS (luminescence wavelength is 472 nm, peak width is 21 nm) on the surface of the first material film layer to obtain a luminescent layer with a thickness of 40 nm.

[0129] (6) Spin-coat a ZnMgO ethanol solution on the light-emitting layer to obtain an electron transport layer with a thickness of 60 nm.

[0130] (7) Place the semi-finished product obtained in step (6) into a vacuum chamber, evaporate a layer of Ag with a thickness of 90 nm on the surface of the electron transport layer as a cathode, and encapsulate to obtain a QLED device. Bake the device at 120° C. for 30 min, and then perform subsequent performance tests on the device that has completed the heat treatment.

[0131] Example 2

[0132] The scheme of this embodiment is basically the same as that of Embodiment 1, with the only difference being that, in this embodiment, in step (4), the mass ratio of the first material in the first material film layer to the mass ratio of TFB in the hole transport layer is 0.1:1; accordingly, the thickness of the first material film layer is changed to 90 nm, and the thickness of the hole transport layer is changed to 6 nm.

[0133] Example 3

[0134] The scheme of this embodiment is basically the same as that of Embodiment 1, with the only difference being that, in this embodiment, in step (4), the mass ratio of the first material in the first material film layer to the mass ratio of TFB in the hole transport layer is 1:1; accordingly, the thickness of the first material film layer is changed to 90 nm, and the thickness of the hole transport layer is changed to 60 nm.

[0135] Example 4

[0136] The scheme of this embodiment is basically the same as that of Embodiment 1, with the only difference being that, in this embodiment, in step (4), the mass ratio of the first material in the first material film layer to the mass ratio of TFB in the hole transport layer is 1.1:1; accordingly, the thickness of the first material film layer is changed to 90 nm, and the thickness of the hole transport layer is changed to 66 nm.

[0137] Example 5

[0138] The scheme of this embodiment is basically the same as that of embodiment 1, except that, in this embodiment, the first material is directly doped into the hole transport layer, and accordingly:

[0139] Omit step (4);

[0140] Step (3) is changed to: dispersing TFB and TAPC in toluene at a mass ratio of TAPC to TFB of 0.5:1 and a final TFB concentration of 30 mg / ml to prepare a mixed solution;

[0141] The substrate was transferred to a glove box filled with nitrogen atmosphere, the mixed solution was spin-coated on the surface of the hole injection layer, and annealed at 200° C. for 30 min to obtain a hole functional layer with a thickness of 120 nm. The hole functional layer was used to prepare the light-emitting layer in step (5).

[0142] Example 6

[0143] The scheme of this embodiment is basically the same as that of Embodiment 1, except that in this embodiment, in step (5), the quantum dot material is changed to CdZnSe / CdZnSe / CdZnS / ZnS (luminescence wavelength is 472nm, peak width is 22nm).

[0144] Example 7

[0145] The scheme of this embodiment is basically the same as that of Embodiment 1, with the only difference being that in this embodiment, in step (5), the quantum dot material is changed to CdZnSe / CdZnSe / ZnS / CdZnS / ZnS (luminescence wavelength is 471 nm, peak width is 21 nm).

[0146] Example 8

[0147] The scheme of this embodiment is basically the same as that of Embodiment 1, except that, in this embodiment, in step (4), the first material is changed to PVK.

[0148] Example 9

[0149] The scheme of this embodiment is basically the same as that of Embodiment 1, except that, in this embodiment, in step (5), the first material is changed to TPDI.

[0150] Example 10

[0151] The scheme of this embodiment is basically the same as that of embodiment 1, except that, in this embodiment, in step (5), the first material is changed to Spiro-TPD.

[0152] Embodiment 11

[0153] The scheme of this embodiment is basically the same as that of embodiment 5, except that in this embodiment, in step (4), the mass ratio of TAPC to TFB is 0.1:1.

[0154] Example 12

[0155] The scheme of this embodiment is basically the same as that of embodiment 5, except that in this embodiment, in step (4), the mass ratio of TAPC to TFB is 1:1.

[0156] Embodiment 13

[0157] The scheme of this embodiment is basically the same as that of embodiment 5, except that in this embodiment, in step (4), the mass ratio of TAPC to TFB is 1.1:1.

[0158] Embodiment 14

[0159] The scheme of this embodiment is basically the same as that of Embodiment 5, with the only difference being that in this embodiment, in step (5), the first material is changed to PVK.

[0160] Comparative Example 1

[0161] The scheme of comparative example 1 is basically the same as that of embodiment 1, except that in comparative example 1, the first material film layer is removed from the device, and accordingly, in the preparation steps, step (4) is omitted, and the preparation of the light-emitting layer in step (5) is directly performed on the hole functional layer prepared in step (3).

[0162] Comparative Example 2

[0163] The scheme of Comparative Example 2 is basically the same as that of Example 1, except that, in Comparative Example 2, the first material film layer is disposed between the hole injection layer and the hole transport layer, and accordingly, steps (3) and (4) are changed to:

[0164] (3) The substrate was transferred to a glove box filled with nitrogen atmosphere, and a toluene solution of the first material was spin-coated on the surface of the hole injection layer. The solution was annealed at 150° C. for 15 min to obtain a first material film layer with a thickness of 30 nm, wherein the first material was TAPC.

[0165] (4) Spin-coat a chlorobenzene solution of TFB with a concentration of 30 mg / ml on the surface of the hole injection layer, and then anneal at 200° C. for 20 min to obtain a hole transport layer with a thickness of 90 nm. The mass ratio of the first material in the first material film layer to the mass ratio of TFB in the hole transport layer is 0.5:1. Subsequently, the preparation of the light-emitting layer in step (5) is performed on the hole functional layer obtained in this step.

[0166] The performance parameters of the quantum dot material and the first material involved in the above embodiments are shown in Table 1.

[0167] Table 1

[0168]

[0169] The devices prepared in the above embodiments and comparative examples were tested. The results are recorded in Table 2. The test method is as follows:

[0170] (1) External quantum efficiency EQE test

[0171] External quantum efficiency EQE represents the ratio of the number of electron-hole pairs injected into quantum dots to the number of emitted photons. The unit is %, which is an important parameter to measure the quality of electrophotoelectric devices. It can be obtained by measuring with EQE optical testing instruments. The specific calculation formula is as follows:

[0172]

[0173] Among them, η e is the light output coupling efficiency, η γ is the ratio of the number of recombined carriers to the number of injected carriers, x is the ratio of the number of excitons that generate photons to the total number of excitons, K R is the radiation process rate, K NR is the rate of the non-radiative process.

[0174] Test conditions: carried out at room temperature, air humidity is 30-60%.

[0175] (2) Life test refers to the time taken for the device brightness to decay to a certain percentage of the maximum brightness under 2mA constant current drive. The time taken for the brightness to decay to 95% of the maximum brightness is defined as T95, and this life is the measured life. In order to shorten the life test cycle, the device life test is usually carried out at high brightness by accelerating device aging, and the life at low brightness is obtained by fitting the decay fitting formula. For example, the life at 1000nits is recorded as T95 1000nits, and the calculation formula is:

[0176]

[0177] Among them, T95 LThe lifespan under low brightness, generally 1000nits, T95 H is the lifespan under high brightness, that is, the measured lifespan, L H is the maximum brightness that the device is accelerated to, L L Generally it is 1000nits, A is the acceleration factor, which is 1.7.

[0178] (3) Rise duration: The time required for the brightness of a device to rise to the highest point when driven by a constant current or voltage is defined as the rise duration.

[0179] Table 2

[0180]

[0181]

[0182] Refer to Table 2, we can see that:

[0183] Each embodiment has a shorter rising period than comparative examples 1 and 2. At the same time, each embodiment has a higher T95@1000nits and EQE, indicating that by providing the first material inside the hole transport layer or on the side facing the light-emitting layer, the formation of excitons in the hole transport layer can be suppressed without affecting the luminous efficiency and life of the device, thereby improving the problem of a significant increase in brightness of the device during the life test.

[0184] The optoelectronic devices, preparation methods and display devices provided in the embodiments of the present application are introduced in detail above. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the methods and core ideas of the present application. At the same time, for technicians in this field, according to the ideas of the present application, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on the present application.

Claims

1. A photoelectric device, comprising an anode, a hole functional layer, a light-emitting layer and a cathode stacked in sequence, characterized in that: The hole functional layer comprises a hole transport layer, and a first material is disposed inside the hole transport layer and / or on a side of the hole transport layer facing the light-emitting layer; The absolute value of the difference between the LUMO energy level of the first material and the valence band energy level of the material of the light-emitting layer is greater than or equal to 1.0 eV.

2. The optoelectronic device according to claim 1, characterized in that: The absolute value of the difference between the LUMO energy level of the first material and the valence band energy level of the material of the light-emitting layer is greater than or equal to 1.0 eV and less than or equal to 2.0 eV; And / or, the hole mobility of the first material is greater than or equal to 1×10 -6 cm 2 / (V·s).

3. The optoelectronic device according to claim 1 or 2, characterized in that: The hole mobility of the first material is greater than or equal to 1×10 -6 cm 2 / (V·s), and less than or equal to 1×10 -2 cm 2 / (V·s); And / or, the first material includes one or more of Spiro-OMeTAD, Spiro-TPD, TAPC, TPDI, TCTA, and PVK.

4. The optoelectronic device according to claim 1, characterized in that: In the hole functional layer, the mass ratio of the first material to the material of the hole transport layer is 0.1 to 1:1; and / or, The first material disposed on the side of the hole transport layer facing the light-emitting layer is formed into a film layer, and the thickness of the film layer is 20 to 120 nm.

5. The optoelectronic device according to claim 1, characterized in that: The hole transport layer includes materials such as 4,4'-N,N'-dicarbazolyl-biphenyl, N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, tris(3-methylphenylphenylamino)-triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))] and poly(4-butylphenyl-diphenylamine) , polyaniline, polypyrrole, poly(p-)phenylene vinylene, poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], copper phthalocyanine, aromatic tertiary amines, polynuclear aromatic tertiary amines, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compounds, N,N,N',N'-tetraarylbenzidine, PEDOT:PSS and its derivatives, poly(N-vinylcarbazole) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-di(naphthalene-1-yl)-N,N'-diphenylbenzidine, spiro NPB; And / or, the photoelectric device further comprises a hole injection layer, the hole injection layer being arranged between the hole functional layer and the anode; the material of the hole injection layer comprises poly(ethylenedioxythiophene): polystyrene sulfonate, poly(9,9-dioctyl-fluorene-co-N-(4-butylphenyl)-diphenylamine), polyarylamine, poly(N-vinylcarbazole), polyaniline, polypyrrole, N,N,N',N'-tetrakis(4-methoxyphenyl)-benzidine, 4-bis[N-(1-naphthyl)-N-phenyl-amino]biphenyl, One or more of 4,4',4"-tri[phenyl(m-tolyl)amino]triphenylamine, 4,4',4"-tri(N-carbazolyl)-triphenylamine, 1,1-bis[(di-4-tolylamino)phenylcyclohexane, 4,4',4"-tri(diphenylamino)triphenylamine doped with tetrafluoro-tetracyano-quinodimethane, p-doped phthalocyanine, F4-TCNQ doped N,N'-diphenyl-N,N'-di(1-naphthyl)-1,1'-biphenyl-4,4"-diamine, hexaazatriphenylene-capronitrile; And / or, the photoelectric device further comprises an electron transport layer disposed between the light-emitting layer and the cathode, the material of the electron transport layer comprising one or more of metal oxides and doped metal oxides; the metal oxides comprising one or more of ZnO, TiO2, SnO2, ZrO, Al2O3, WO3, HfO3, Ta2O3, ZrSiO4, BaTiO3, BaZrO3; the metal oxides in the doped metal oxides comprising a plurality of ZnO, TiO2, SnO2, ZrO, Al2O3, WO3, HfO3, Ta2O3, ZrSiO4, BaTiO3, BaZrO3, the doping elements comprising one or more of Al, Mg, Li, In, Ga, Cd, Cs, Cu; And / or, the anode and the cathode are independently selected from a doped metal oxide particle electrode, a composite electrode of a metal and a metal oxide, a graphene electrode, a carbon nanotube electrode, a metal electrode or an alloy electrode, the material of the doped metal oxide particle electrode is selected from one or more of indium-doped tin oxide, fluorine-doped tin oxide, antimony-doped tin oxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, indium-doped zinc oxide, magnesium-doped zinc oxide and aluminum-doped magnesium oxide, the composite electrode of the metal and the metal oxide is selected from AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, TiO2 / Ag / TiO2, TiO2 / Al / TiO2, ZnS / Ag / ZnS, ZnS / Al / ZnS, and the material of the metal electrode is selected from one or more of Ag, Al, Cu, Mo, Au, Pt, Si, Ca, Mg and Ba; And / or, the material of the light-emitting layer includes at least one of single-structure quantum dots, core-shell quantum dots and perovskite semiconductor materials; the material of the single-structure quantum dots, the core material of the core-shell quantum dots and the shell material of the core-shell quantum dots are respectively selected from at least one of II-VI compounds, IV-VI compounds, III-V compounds and I-III-VI compounds; the II-VI compounds are selected from CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, Zn At least one of CdS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe; the IV-VI group compound is selected from SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, At least one of PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe; the III-V group compound is selected from GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAl At least one of GaNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs and InAlPSb; the I-III-VI group compound is selected from at least one of CuInS2, CuInSe2 and AgInS2; the perovskite semiconductor material is selected from doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors; the inorganic perovskite semiconductor has a general structural formula of AMX3, wherein A is Cs + ion, M is a divalent metal cation selected from Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ At least one of, X is a halogen anion selected from Cl - Br - ,I - At least one of the following; the general structural formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, wherein B is an organic amine cation selected from CH3(CH2) n-2 NH3 + or [NH3(CH2) n NH3] 2+ , where n≥2, M is a divalent metal cation selected from Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ At least one of, X is a halogen anion selected from Cl - Br - ,I - At least one of .

6. A method for preparing a photoelectric device, characterized in that: The following steps are involved: providing a first electrode; Disposing a plurality of film layers on one side of the first electrode; Disposing a second electrode on a side of the plurality of film layers away from the first electrode to obtain a photoelectric device; Wherein, one of the first electrode and the second electrode is an anode and the other is a cathode, the multiple film layers include a light-emitting layer and a hole functional layer, and the light-emitting layer is arranged between the hole functional layer and the cathode; The preparation of the hole functional layer includes: providing a hole transport material and a first material; depositing the hole transport material and the first material to form a hole functional layer, wherein the hole functional layer includes a hole transport layer, and the first material is arranged inside the hole transport layer and / or on the side of the hole transport layer facing the light-emitting layer, wherein the absolute value of the difference between the LUMO energy level of the first material and the valence band energy level of the material of the light-emitting layer is greater than or equal to 1.0 eV.

7. The preparation method according to claim 6, characterized in that: The mass ratio of the first material to the hole transport material is 0.1 to 1:1; And / or, the first material includes one or more of Spiro-OMeTAD, Spiro-TPD, TAPC, TPDI, TCTA, and PVK, and the hole transport material includes 4,4'-N,N'-dicarbazolyl-biphenyl, N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4"-diamine, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, tris(3-methylphenylphenylamino)-triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-( One or more of poly(4-sec-butylphenyl)diphenylamine))] and poly(4-butylphenyl-diphenylamine), polyaniline, polypyrrole, poly(p-phenylene vinylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], copper phthalocyanine, aromatic tertiary amine, polynuclear aromatic tertiary amine, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compound, N,N,N',N'-tetraarylbenzidine, PEDOT:PSS and its derivatives, poly(N-vinylcarbazole) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-di(naphthalene-1-yl)-N,N'-diphenylbenzidine, and spiro NPB; And / or, the material of the light-emitting layer includes at least one of single-structure quantum dots, core-shell quantum dots and perovskite semiconductor materials; the material of the single-structure quantum dots, the core material of the core-shell quantum dots and the shell material of the core-shell quantum dots are respectively selected from at least one of II-VI compounds, IV-VI compounds, III-V compounds and I-III-VI compounds; the II-VI compounds are selected from CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, Zn At least one of CdS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe; the IV-VI group compound is selected from SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, At least one of PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe; the III-V group compound is selected from GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAl At least one of GaNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs and InAlPSb; the I-III-VI group compound is selected from at least one of CuInS2, CuInSe2 and AgInS2; the perovskite semiconductor material is selected from doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors; the inorganic perovskite semiconductor has a general structural formula of AMX3, wherein A is Cs + ion, M is a divalent metal cation selected from Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ At least one of, X is a halogen anion selected from Cl - Br - ,I - At least one of the following; the general structural formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, wherein B is an organic amine cation selected from CH3(CH2) n-2 NH3 + or [NH3(CH2) n NH3] 2+ , where n≥2, M is a divalent metal cation selected from Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ At least one of, X is a halogen anion selected from Cl - Br - ,I - At least one of .

8. The preparation method according to claim 7, characterized in that: The providing of a hole transport material and a first material; The step of depositing the hole transport material and the first material to form a hole functional layer comprises: Mixing a hole transport material, a first material and a first solvent to obtain a mixed solution; depositing the mixed solution and then performing a first annealing treatment to obtain the hole functional layer; or, Dispersing a first material in a second solvent to obtain a first material solution, depositing the first material solution, and then performing a second annealing treatment to obtain a first film layer; dispersing a hole transport material in a second solvent to obtain a hole transport solution, depositing the hole transport solution, and then performing a third annealing treatment to obtain a second film layer, wherein the first film layer and the second film layer together constitute a hole functional layer; or The first material includes a first sub-material and a second sub-material; the first sub-material is dispersed in a fourth solvent to obtain a sub-material solution, the first sub-material solution is deposited, and then a fourth annealing treatment is performed to obtain a third film layer; the hole transport material and the second sub-material are dispersed in a fifth solvent to obtain a hole mixed solution, the hole mixed solution is deposited, and then a fifth annealing treatment is performed to obtain a fourth film layer, and the third film layer and the fourth film layer together constitute a hole functional layer.

9. The preparation method according to claim 8, characterized in that: The first solvent includes one or more of chlorobenzene, toluene, and xylene; and / or, The temperature of the first annealing treatment is 150-200° C.; and / or, The first annealing treatment lasts for 10 to 120 minutes; and / or, The second solvent includes one or more of chlorobenzene, toluene and xylene; and / or, The temperature of the second annealing treatment is 150-250° C.; and / or, The second annealing treatment lasts for 10 to 120 minutes; and / or, The third solvent includes one or more of chlorobenzene, toluene and xylene; and / or, The temperature of the third annealing treatment is 150-200° C.; and / or, The third annealing treatment lasts for 10 to 120 minutes; and / or, The fourth solvent includes one or more of chlorobenzene, toluene, and xylene; and / or, The temperature of the fourth annealing treatment is 150-250° C.; and / or, The fourth annealing treatment lasts for 10 to 120 minutes; and / or, The fifth solvent includes one or more of chlorobenzene, toluene, and xylene; and / or, The temperature of the fifth annealing treatment is 150-200° C.; and / or, The fifth annealing treatment takes 10 to 120 minutes.

10. A display device, characterized in that: The invention comprises the optoelectronic device according to any one of claims 1 to 5, or comprises the optoelectronic device prepared by the preparation method according to any one of claims 6 to 9.

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