Photoelectric device, preparation method thereof and display device

Abstract

The invention discloses a photoelectric device, a preparation method thereof and a display device.The photoelectric device comprises a first electrode, a charge function layer and a second electrode which are stacked in sequence, and further comprises a light-emitting layer located between the first electrode and the charge function layer or located between the second electrode and the charge function layer, the material of the charge function layer comprises black titanium dioxide particles. The charge function layer of the photoelectric device is made of the black titanium dioxide particles, titanium ions on the surfaces of the black titanium dioxide particles comprise trivalent titanium Ti < 3 + > and Ti < 4 + >, titanium ions inside the black titanium dioxide particles are tetravalent titanium Ti < 4 + >, the conduction band of the trivalent titanium is lower than that of the tetravalent titanium, electron transmission is better facilitated, and therefore the efficiency of the photoelectric device is effectively improved.

Description

Technical Field

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

[0002] Currently, the widely used optoelectronic devices are organic light-emitting devices (OLED) and quantum dot light-emitting devices (QLED). OLED has become the mainstream technology in the field of display technology due to its excellent display performance such as self-luminescence, simple structure, ultra-thinness, fast response speed, wide viewing angle, low power consumption, and flexible display. QLED has the advantages of saturated color of emitted light, adjustable wavelength, low start-up voltage, good solution processability, easy fine control of quantum dots, and high quantum yield of photoluminescence and electroluminescence. In recent years, it has become a strong competitor of OLED.

[0003] The structure of traditional OLED and QLED devices generally includes an anode, a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer and a cathode. Under the action of the electric field, the holes generated by the anode of the optoelectronic device and the electrons generated by the cathode move and are injected into the hole transport layer and the electron transport layer respectively, and finally migrate to the light-emitting layer. When the two meet in the light-emitting layer, energy excitons are generated, thereby exciting the light-emitting molecules and finally producing visible light.

[0004] The efficiency of existing optoelectronic devices is relatively low and needs to be further improved. Summary of the invention

[0005] In view of this, the present application provides a photoelectric device, aiming to improve the problem of low efficiency of existing photoelectric devices.

[0006] An embodiment of the present application is implemented as follows: a photoelectric device includes a first electrode, a charge functional layer, and a second electrode stacked in sequence, and also includes a light-emitting layer located between the first electrode and the charge functional layer or between the second electrode and the charge functional layer, wherein the material of the charge functional layer includes black titanium dioxide particles.

[0007] Optionally, in some embodiments of the present application, the titanium ions in the black titanium dioxide particles include Ti 4+ and Ti 3+ , where Ti 3+ The molar fraction in titanium ions is 0.1 to 50%.

[0008] Optionally, in some embodiments of the present application, Ti 3+ The molar fraction of titanium ions is 15 to 25%.

[0009] Optionally, in some embodiments of the present application, the material of the charge functional layer is composed of the black titanium dioxide particles.

[0010] Optionally, in some embodiments of the present application, the average particle size of the black titanium dioxide particles is in the range of 1 to 10 nm; and / or

[0011] The thickness of the charge functional layer is in the range of 20 to 150 nm.

[0012] Optionally, in some embodiments of the present application, the first electrode and the second electrode independently include a doped metal oxide particle electrode, a composite electrode, a graphene electrode, a carbon nanotube electrode, a metal element electrode or an alloy electrode, and the material of the doped metal oxide particle electrode includes 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, and the composite electrode includes AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, TiO 2 / Ag / TiO 2 、TiO 2 / Al / TiO 2 , ZnS / Ag / ZnS or ZnS / Al / ZnS, the material of the metal single substance electrode includes one or more of Ag, Al, Cu, Mo, Au, Pt, Ca, Mg and Ba; and / or

[0013] The material of the light-emitting layer includes an organic light-emitting material or a quantum dot light-emitting material, and the organic light-emitting material includes one or more of 4,4'-bis(N-carbazole)-1,1'-biphenyl:tri[2-(p-tolyl)pyridine iridium(III), 4,4',4"-tri(carbazole-9-yl)triphenylamine:tri[2-(p-tolyl)pyridine iridium, diaromatic anthracene derivatives, distilbene aromatic derivatives, pyrene derivatives, fluorene derivatives, TBPe fluorescent materials, TTPX fluorescent materials, TBRb fluorescent materials, DBP fluorescent materials, delayed fluorescent materials, TTA materials, thermally activated delayed materials, polymers containing covalent bonds of BN, hybrid localized charge transfer excited state materials, exciplex light-emitting materials, polyacetylene and its derivatives, polyparaphenylene and its derivatives, polythiophene and its derivatives, polyfluorene and its derivatives;The quantum dot luminescent material includes one or more 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 independently selected from one or more of group II-VI compounds, group IV-VI compounds, group III-V compounds and group I-III-VI compounds. The group II-VI compounds include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSe Te, 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 includes SnS, S The III-V group compounds include one or more of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaP One or more of Sb, AlNP, 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, and the Group I-III-VI compound includes CuInS; 2 、CuInSe 2 AgInS 2 One or more of; the perovskite semiconductor material includes a doped or undoped inorganic perovskite semiconductor or an organic-inorganic hybrid perovskite semiconductor, and the inorganic perovskite semiconductor has a general structural formula of AMX 3 , where A is Cs + ions, M is a divalent metal cation, including Pb2 + Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ One or more of, X is a halogen anion, including Cl - Br - ,I - One or more of the organic-inorganic hybrid perovskite semiconductor has the general structural formula of BMX 3 , where B is an organic amine cation, including CH 3 (CH 2 ) n-2 NH 3 + or [NH 3 (CH 2 ) n NH 3 ] 2+ , where n≥2, M is a divalent metal cation, including Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ One or more of, X is a halogen anion, including Cl - Br - ,I - One or more of; and / or

[0014] The photoelectric device also includes a hole transport layer located on a side of the light-emitting layer away from the charge functional layer, wherein the material of the hole transport layer includes 4,4'-N,N'-dicarbazolyl-biphenyl, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], 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, poly(N,N'-bis(4-butylphenyl)-N, N'-bis(phenyl)benzidine), N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, 4,4',4'-tri(N-carbazolyl)-triphenylamine, 4,4',4'-tri(N-3-methylphenyl-N-phenylamino)triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))], poly(N-vinylcarbazole) and its derivatives, N,N'-di(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4-4'-diamine, spiro NPB, poly(phenylene vinylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene, 4,4'-cyclohexylbis[N,N-di(4-methoxyphenyl)amino]- [(4-(4-phenyl)aniline], 1,3-di(carbazole-9-yl)benzene, polyaniline, polypyrrole, poly(p-phenylene vinylene), 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, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, doped graphene, undoped graphene, C60, doped or undoped NiO, doped or undoped MoO 3 , doped or undoped WO 3 , doped or undoped V 2 O 5 , doped or undoped P-type GaN, doped or undoped CrO 3 , one or more of doped or undoped CuO; and / or

[0015] The photoelectric device further comprises a hole injection layer located on a side of the light-emitting layer away from the charge functional layer, wherein the hole injection layer comprises 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, PEDOT, PEDOT:PSS, PEDOT:PSS doped with s-MoO 3 One or more of derivatives of, 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, tetracyanoquinodimethane, copper phthalocyanine, nickel oxide, molybdenum oxide, tungsten oxide, vanadium oxide, molybdenum sulfide, tungsten sulfide and copper oxide.

[0016] Accordingly, an embodiment of the present application further provides a method for preparing a photoelectric device, comprising:

[0017] Providing a photovoltaic device preform, wherein the photovoltaic device preform comprises a first electrode;

[0018] Providing black titanium dioxide, and disposing the black titanium dioxide on the photovoltaic device preform to obtain a charge functional layer;

[0019] A second electrode is formed on a surface of the charge functional layer away from the first electrode to obtain a photoelectric device.

[0020] Optionally, in some embodiments of the present application, the optoelectronic device preform further includes a light-emitting layer disposed on the first electrode; or

[0021] The forming of the second electrode on the charge functional layer comprises: sequentially forming a stacked light emitting layer and a second electrode on the charge functional layer.

[0022] Optionally, in some embodiments of the present application, the method of disposing the black titanium dioxide on the optoelectronic device preform includes: dissolving the black titanium dioxide in a first solvent to obtain a dispersion, disposing the dispersion on the optoelectronic device preform, and annealing.

[0023] Optionally, in some embodiments of the present application, in the dispersion, the concentration of the black titanium dioxide is 5 to 100 mg / mL; and / or

[0024] The first solvent includes an alcohol solvent, and the alcohol solvent includes one or more of methanol, ethanol, isopropanol, and ethylene glycol; and / or

[0025] The annealing temperature is 80-120° C.; and / or

[0026] The annealing time is 5 to 60 minutes.

[0027] Optionally, in some embodiments of the present application, the method for preparing black titanium dioxide comprises:

[0028] Provides white titanium dioxide particles;

[0029] The white titanium dioxide particles are placed in a reducing atmosphere and heat treated at 100 to 1000° C. for 1 to 72 hours to obtain black titanium dioxide particles.

[0030] Optionally, in some embodiments of the present application, the optoelectronic device preform further includes a hole transport layer and a light emitting layer sequentially stacked on the first electrode; or

[0031] The forming of the second electrode on the charge functional layer comprises: sequentially forming a stacked light emitting layer, a hole transport layer and a second electrode on the charge functional layer; or

[0032] The photoelectric device preform further comprises a hole injection layer, a hole transport layer and a light emitting layer sequentially stacked on the first electrode; or

[0033] The forming of the second electrode on the charge functional layer comprises: sequentially forming a light emitting layer, a hole transport layer, a hole injection layer and a second electrode stacked on the charge functional layer.

[0034] Correspondingly, an embodiment of the present application further provides a display device, which includes the above-mentioned optoelectronic device.

[0035] The material of the charge function layer of the photoelectric device described in the present application is black titanium dioxide particles, and the titanium ions on the surface of the black titanium dioxide particles include trivalent titanium Ti 3+ and Ti 4+ , the titanium ion inside is tetravalent titanium Ti 4+ The conduction band of trivalent titanium is lower than that of tetravalent titanium, which is more conducive to the transmission of electrons, thereby effectively improving the efficiency of optoelectronic devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] 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 paying any creative work.

[0037] Figure 1 is a schematic structural diagram of an optoelectronic device provided in an embodiment of the present application;

[0038] Figure 2 is a schematic structural diagram of another optoelectronic device provided in an embodiment of the present application;

[0039] Figure 3 is a schematic structural diagram of another optoelectronic device provided in an embodiment of the present application;

[0040] Figure 4 is a schematic structural diagram of another optoelectronic device provided in an embodiment of the present application;

[0041] Figure 5 is a schematic structural diagram of another optoelectronic device provided in an embodiment of the present application;

[0042] Figure 6 is a schematic structural diagram of another optoelectronic device provided in an embodiment of the present application;

[0043] Figure 7 It is a flow chart of a method for preparing a photoelectric device provided in an embodiment of the present application.

[0044] Reference numerals:

[0045] Optoelectronic device 100 ; first electrode 10 ; charge functional layer 20 ; second electrode 30 ; light emitting layer 40 ; hole transport layer 50 ; hole injection layer 60 . DETAILED DESCRIPTION

[0046] 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.

[0047] In this application, unless otherwise stated, directional words such as "upper" and "lower" generally refer to the upper and lower parts of the device in actual use or working state, specifically the drawing direction in the accompanying drawings; while "inner" and "outer" refer to the outline of the device. In addition, in the description of this application, the term "including" means "including but not limited to". The terms first, second, third, etc. are used only as labels and do not impose numerical requirements or establish an order.

[0048] 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.

[0049] 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.

[0050] In the present application, when a layer is formed "on" another layer, the so-called "on" is a broad concept, which may indicate that the formed another layer is adjacent to the certain layer, or may indicate that there are other spacing structural layers between the another layer and the certain layer. For example, when a second electrode is formed "on" the first carrier functional layer, the so-called "on" may indicate that the formed second electrode is adjacent to the first carrier functional layer, or may indicate that there are other spacing structural layers between the second electrode and the first carrier functional layer, such as a light-emitting layer.

[0051] 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.

[0052] Titanium dioxide has good stability and electron transport properties and is used in the charge functional layer of optoelectronic devices. Currently, white titanium dioxide is commonly used in optoelectronic devices. However, the efficiency of optoelectronic devices prepared from white titanium dioxide is low and needs to be further improved.

[0053] The technical solution of this application is as follows:

[0054] First, see Figures 1-2 An embodiment of the present application provides a photoelectric device 100, comprising a first electrode 10, a charge functional layer 20 and a second electrode 30 stacked in sequence, wherein the material of the charge functional layer 20 comprises black titanium dioxide particles.

[0055] In some embodiments, the optoelectronic device 100 further includes a light-emitting layer 40 , and the light-emitting layer 40 is located between the first electrode 10 and the charge functional layer 20 , or between the second electrode 30 and the charge functional layer 20 .

[0056] The material of the charge function layer of the optoelectronic device 100 described in the present application is black titanium dioxide particles. The titanium ions in the black titanium dioxide particles include Ti 4+ and Ti 3+ The titanium ions on the surface of the black titanium dioxide particles include trivalent titanium Ti 3+ and Ti 4+ , the titanium ion inside is tetravalent titanium Ti 4+ The conduction band of trivalent titanium is lower than that of tetravalent titanium, so that the charge functional layer 20 including black titanium dioxide and the light-emitting layer 40 have better energy level matching, which is more conducive to the transmission of electrons from the charge functional layer 20 to the light-emitting layer 40, thereby effectively improving the efficiency and life of the optoelectronic device 100.

[0057] The black titanium dioxide particles were subjected to XPS testing using MgKa as an X-ray radiation source, wherein the photon energy was 1253.6 eV, the voltage was 12.5 KV, and the current was 16 mA. The measured Ti content in the titanium ions of the black titanium dioxide particles was 3+ The molar proportion is 0.1-50%, for example, 0.1-25%, 5-30%, 10-35%, 15-40%, 20-45%, 26-50%, etc. Within the above proportion range, on the one hand, the black titanium dioxide can have a higher electron mobility; on the other hand, since trivalent titanium can increase the surface defects of black titanium dioxide, within the above proportion range, the surface defect states of black titanium dioxide can be reduced, effectively avoiding the exciton recombination caused by excessive defect states; on the other hand, the absorption of light by black titanium dioxide can be effectively reduced, and the light extraction efficiency of the optoelectronic device 100 can be improved.

[0058] In at least one preferred embodiment, the measured titanium ions in the black titanium dioxide particles are Ti 3+ The molar fraction of titanium ions is 15-25%. Within the molar fraction range, the black titanium dioxide has a higher electron mobility, so that the optoelectronic device 100 has a higher current efficiency and a longer lifespan.

[0059] In some embodiments, the material of the charge functional layer consists of the black titanium dioxide particles.

[0060] In some embodiments, the average particle size of the black titanium dioxide particles is in the range of 1 to 10 nm. Within the range, the black titanium dioxide particles have both high electron transport performance and good film-forming properties, and will not affect the light output of the optoelectronic device 100.

[0061] In some embodiments, the thickness of the charge functional layer 20 is in the range of 20 to 150 nm. Within the thickness range, the charge functional layer 20 can have good conductivity and electron transport capability without affecting the light output of the optoelectronic device 100 .

[0062] See also Figures 3-4 In some embodiments, the optoelectronic device 100 further includes a hole transport layer 50 , and the hole transport layer 50 is located on a side of the light emitting layer 40 away from the charge functional layer 20 .

[0063] See also Figures 5-6 In some embodiments, the optoelectronic device 100 further includes a hole injection layer 60 , and the hole injection layer 60 is located on a side of the hole transport layer 50 away from the light-emitting layer 40 .

[0064] The first electrode 10 and the second electrode 30 are electrodes for optoelectronic devices known in the art, for example, they can independently include but are not limited to doped metal oxide electrodes, composite electrodes, graphene electrodes, carbon nanotube electrodes, metal single substance electrodes or alloy electrodes. The material of the doped metal oxide electrode can include but is not limited to one or more of indium doped tin oxide (ITO), fluorine doped tin oxide (FTO), antimony doped tin oxide (ATO), aluminum doped zinc oxide (AZO), gallium doped zinc oxide (GZO), indium doped zinc oxide (IZO), magnesium doped zinc oxide (MZO), aluminum doped magnesium oxide (AMO), and cadmium doped zinc oxide. The composite electrode is an electrode formed by stacking two or more layers of conductive materials, such as AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, TiO 2 / Ag / TiO 2 、TiO 2 / Al / TiO 2 , ZnS / Ag / ZnS, ZnS / Al / ZnS, Ca / Al, LiF / Ca, LiF / Al, BaF 2 / Al、CsF / Al、CaCO 3 / Al、BaF 2 / Ca / Al, etc., where " / " represents a stacked structure, for example, AZO / Ag / AZO represents a composite electrode including an AZO layer, an Ag layer and an AZO layer stacked in sequence. The material of the metal single substance electrode may include but is not limited to one or more of Ag, Ni, Pt, Au, Ir, Cu, Mo, Al, Ca, Mg and Ba. The alloy electrode includes but is not limited to Au:Mg alloy electrode and Ag:Mg alloy electrode.

[0065] In some embodiments, the anode is an electrode with a relatively high work function, for example, it may include but is not limited to a doped metal oxide electrode with a relatively high work function, a metal single substance electrode with a relatively high work function, and a carbon nanotube electrode. The metal single substance electrode with a relatively high work function may be selected from but is not limited to Ni, Pt, Au, Ag, Ir, etc.

[0066] In some embodiments, the cathode is an electrode with a relatively low work function, such as but not limited to a metal single substance electrode with a relatively low work function, a composite electrode with a relatively low work function, and an alloy electrode with a relatively low work function. The metal single substance electrode with a relatively low work function may be Ca, Ba, Al, Mg, etc. The composite electrode with a relatively low work function may be Ca / Al, LiF / Ca, LiF / Al, BaF 2 / Al、CsF / Al、CaCO 3 / Al、BaF 2 / Ca / Al, etc. The alloy electrodes with relatively low work functions are Au:Mg and Ag:Mg, etc.

[0067] The material of the light-emitting layer 40 may include an organic light-emitting material or a quantum dot light-emitting material.

[0068] The organic light-emitting material may include but is not limited to CBP:Ir(mppy) 3 (4,4'-bis(N-carbazole)-1,1'-biphenyl:tris[2-(p-tolyl)pyridine iridium(III)), TCTX:Ir(mmpy)(4,4',4"-tris(carbazole-9-yl)triphenylamine:tris[2-(p-tolyl)pyridine iridium), diaromatic anthracene derivatives, distilbene aromatic derivatives, pyrene derivatives, fluorene derivatives, TBPe fluorescent materials, TTPX fluorescent materials, TBRb fluorescent materials, DBP fluorescent materials, delayed fluorescent materials, TTA materials, TADF (thermally activated delay) materials, polymers containing BN covalent bonds, HLCT (hybridized localized charge transfer excited state) materials, Exciplex (exciplex) luminescent materials, polyacetylene and its derivatives, polyparaphenylene and its derivatives, polythiophene and its derivatives, polyfluorene and its derivatives. One or more thereof.

[0069] The quantum dot light-emitting material may include, but is not limited to, one or more of single structure quantum dots, core-shell structure quantum dots and perovskite semiconductor materials.

[0070] 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 may respectively include but are not limited to one or more of II-VI group compounds, IV-VI group compounds, III-V group compounds and I-III-VI group compounds. The II-VI group compounds may include, but are not limited to, one or more of 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 compounds may include, but are not limited to, one or more 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 may include but is not limited to one or more of 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, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs and InAlPSb. The I-III-VI group compound may include but is not limited to CuInS 2 、CuInSe 2 AgInS 2 One or more of .

[0071] As an example, the core-shell structured quantum dots may include, but are not limited to, one or more of 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.

[0072] The perovskite semiconductor material may include but is not limited to doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors. The inorganic perovskite semiconductor has the general structural formula AMX 3 , where A is Cs + ions, M is a divalent metal cation, including Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ One or more of, X is a halogen anion, including Cl - Br - ,I - The general structural formula of the organic-inorganic hybrid perovskite semiconductor is BMX 3 , where B is an organic amine cation, including CH 3 (CH 2 ) n-2 NH 3 + or [NH 3 (CH 2 ) n NH 3 ] 2+ , where n≥2, M is a divalent metal cation, including Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+One or more of, X is a halogen anion, including Cl - Br - ,I - One or more of .

[0073] The material of the hole transport layer 50 may also be a material known in the art for a hole transport layer, for example, may be selected from but not limited to 4,4'-N,N'-dicarbazolyl-biphenyl (CBP), poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), 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), poly(N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine) (Poly-TPD), N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro(spiro-TPD), N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine (DNTPD), 4,4',4'-tri(N-carbazolyl)-triphenylamine (TCTA), 4,4',4'-tri(N-3-methylphenyl-N-phenylamino)triphenylamine (m-MTDATA), poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))] (TFB), poly(N-vinylcarbazolyl) azole) (PVK) and its derivatives, N,N'-di(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4-4'-diamine (NPB), spiro NPB, poly(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), 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (spiro-omeTAD), 4,4'-cyclohexylbis[N,N-bis(4-methylphenyl)aniline](TAPC), 1,3-bis(carbazole-9-yl)benzene(MCP), polyaniline, polypyrrole, poly(p-phenylene vinylene), 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, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, doped graphene, undoped graphene, C60, doped or undoped NiO, doped or undoped MoO 3 , doped or undoped WO3 , doped or undoped V 2 O 5 , doped or undoped P-type GaN, doped or undoped CrO 3 , doped or undoped CuO or more.

[0074] The material of the hole injection layer 60 may also be a material known in the art for a hole injection layer, for example, may be selected from but not limited to 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (HAT-CN), PEDOT, PEDOT:PSS, PEDOT:PSS doped with s-MoO 3 Derivatives (PEDOT:PSS:s-MoO 3 ), one or more of 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine (m-MTDATA), tetracyanoquinodimethane (F4-TCQN), copper phthalocyanine, nickel oxide, molybdenum oxide, tungsten oxide, vanadium oxide, molybdenum sulfide, tungsten sulfide and copper oxide.

[0075] It is understandable that the optoelectronic device 100 may also be provided with some functional layers conventionally used in optoelectronic devices to help improve the performance of the optoelectronic device, such as an electron blocking layer, a hole blocking layer, an electron injection layer, an interface modification layer, etc.

[0076] It can be understood that the materials of each layer of the optoelectronic device 100 can be adjusted according to the light emitting requirements of the optoelectronic device 100 .

[0077] In some embodiments, the optoelectronic device 100 further includes a substrate, and the substrate is disposed on a side of the first electrode 10 away from the light-emitting layer 40 , or the substrate is disposed on a side of the second electrode 30 away from the light-emitting layer 40 .

[0078] The substrate may be a rigid substrate or a flexible substrate. In some embodiments, the material of the substrate may include but is not limited to one or more of glass, silicon wafer, polycarbonate, polymethyl methacrylate, polyethylene terephthalate, polyethylene naphthalate, polyamide and polyether sulfone.

[0079] It can be understood that the optoelectronic device 100 can be an upright optoelectronic device or an inverted optoelectronic device. The optoelectronic device 100 can be a quantum dot optoelectronic device (QLED) or an organic optoelectronic device (OLED).

[0080] The charge functional layer 20 of the optoelectronic device 100 includes black titanium dioxide, thereby having higher luminous efficiency and longer lifespan.

[0081] Second, please refer to Figures 1-2 and Figure 7 The present application also provides a method for preparing a photoelectric device, comprising the following steps:

[0082] Step S11, providing a photoelectric device preform, wherein the photoelectric device preform includes a first electrode 10;

[0083] Step S12, providing black titanium dioxide, and disposing the black titanium dioxide on the photoelectric device preform to obtain a charge functional layer 20;

[0084] Step S13 , forming a second electrode 30 on a surface of the charge functional layer 20 away from the first electrode to obtain a photoelectric device 100 .

[0085] See also Figure 1 In some embodiments, the optoelectronic device preform further includes a light-emitting layer 40 disposed on the first electrode 10 , and the black titanium dioxide is disposed on the light-emitting layer 40 .

[0086] See also Figure 2 In some other embodiments, forming the second electrode 30 on the charge functional layer 20 includes: sequentially forming a stacked light-emitting layer 40 and the second electrode 30 on the charge functional layer 20 .

[0087] See also Figure 3 In some embodiments, the optoelectronic device preform further includes a hole transport layer 50 and a light-emitting layer 40 which are sequentially stacked on the first electrode 10 , and the black titanium dioxide is disposed on the light-emitting layer 40 .

[0088] See also Figure 4 In some other embodiments, forming the second electrode 30 on the charge functional layer 20 includes: sequentially forming a stacked light-emitting layer 40, a hole transport layer 50 and a second electrode 30 on the charge functional layer 20.

[0089] See also Figure 5 In some embodiments, the optoelectronic device preform further includes a hole injection layer 60 , a hole transport layer 50 and a light-emitting layer 40 which are sequentially stacked on the first electrode 10 , and the black titanium dioxide is disposed on the light-emitting layer 40 .

[0090] See also Figure 6 In other embodiments, forming the second electrode 30 on the charge functional layer 20 includes: sequentially forming a light-emitting layer 40, a hole transport layer 50, a hole injection layer 60 and a second electrode 30 stacked on the charge functional layer 20.

[0091] The method of forming the second electrode 30, the light-emitting layer 40, the hole transport layer 50, and the hole injection layer 60, as well as the method of setting the black titanium dioxide on the optoelectronic device preform can be implemented 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 plating and solution method, among which the physical plating method includes: thermal evaporation coating, electron beam evaporation coating, magnetron sputtering, multi-arc ion plating, 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, and strip coating.

[0092] In at least some embodiments, the method of disposing the black titanium dioxide on the optoelectronic device preform includes: dissolving the black titanium dioxide in a first solvent to obtain a dispersion, and spin-coating the dispersion on the optoelectronic device preform.

[0093] The first solvent includes but is not limited to alcohol solvents, and the alcohol solvent includes but is not limited to one or more of methanol, ethanol, isopropanol, and ethylene glycol.

[0094] In some embodiments, in the dispersion, the concentration of the black titanium dioxide is 5 to 100 mg / mL, for example, 5 to 55 mg / mL, 10 to 60 mg / mL, 15 to 65 mg / mL, 20 to 70 mg / mL, 25 to 75 mg / mL, 30 to 80 mg / mL, 35 to 85 mg / mL, 40 to 90 mg / mL, 45 to 95 mg / mL, 50 to 100 mg / mL, etc. Within the concentration range, the black titanium dioxide is uniformly dispersed in the solvent, which is conducive to preparing a charge functional layer 20 with good film-forming effect and suitable thickness.

[0095] In some embodiments, the step of spin coating the dispersion on the optoelectronic device preform further includes annealing, which is conducive to preparing a charge functional layer 20 with good crystallinity and excellent performance.

[0096] The annealing temperature is 80-120° C., for example, 80-100° C., 85-105° C., 90-110° C., 95-115° C., 98-120° C., etc., and the annealing time is 5-60 min., for example, 5-35 min., 10-40 min., 15-45 min., 20-50 min., 25-55 min., 30-60 min., etc. Within the temperature and time range, it is beneficial to prepare a charge functional layer 20 with a good film-forming effect.

[0097] The preparation method of the black titanium dioxide comprises:

[0098] Step S21: providing white titanium dioxide particles;

[0099] Step S22: placing the white titanium dioxide particles in a reducing atmosphere and subjecting them to heat treatment to obtain black titanium dioxide particles.

[0100] In some embodiments, the average particle size of the white titanium dioxide particles is in the range of 1 to 10 nm. The particle size range is conducive to preparing black titanium dioxide particles with a suitable particle size.

[0101] The gas in the reducing atmosphere includes hydrogen.

[0102] In some embodiments, the reducing atmosphere may further include an inert gas, including but not limited to one or more of helium, argon, and nitrogen. When the reducing atmosphere also includes an inert gas, the volume proportion of hydrogen in the reducing atmosphere is greater than or equal to 5% and less than 100%. In this way, hydrogen is conducive to reducing the surface of the white titanium dioxide particles to obtain black titanium dioxide particles with trivalent titanium on the surface.

[0103] In some embodiments, the temperature of the heat treatment is 100-1000° C., for example, 100-550° C., 150-600° C., 200-650° C., 250-700° C., 300-750° C., 350-800° C., 400-850° C., 450-900° C., 500-950° C., 520-1000° C., etc., and the time is 1-72 hours, for example, 1-45 hours, 5-50 hours, 10-55 hours, 15-60 hours, 20-65 hours, 25-70 hours, 30-40 hours, etc. Within the temperature and time range of the heat treatment, the degree of reduction of the white titanium dioxide by hydrogen can be effectively controlled, so that the surface of the prepared black titanium dioxide has an appropriate amount of trivalent titanium, so that the charge functional layer 20 including the black titanium dioxide and the light-emitting layer 40 have better energy level matching. In addition, the more trivalent titanium there is on the surface of black titanium dioxide, the higher its electron mobility. However, the conversion of tetravalent titanium into trivalent titanium will lead to more surface defects in black titanium dioxide. The more trivalent titanium there is, the more surface defects there are. The increase in defects will cause exciton recombination, thereby affecting the luminous efficiency and lifespan of optoelectronic devices, resulting in reduced luminous efficiency and shortened lifespan of optoelectronic devices.

[0104] It can be understood that when the optoelectronic device 100 also includes functional layers conventionally used in optoelectronic devices that help improve the performance of the optoelectronic device, such as an electron blocking layer, a hole blocking layer, an electron injection layer, an interface modification layer, etc., the preparation method of the optoelectronic device 100 may also include the step of preparing the above-mentioned functional layers using conventional techniques in the field.

[0105] The method for preparing the optoelectronic device described in the present application can prepare an optoelectronic device 100 having good luminous efficiency and long life.

[0106] In a third aspect, the present application further relates to a display device, wherein the display device comprises the optoelectronic device 100 .

[0107] The display device can be any electronic product with a display function, including but not limited to smart phones, tablet computers, laptops, digital cameras, digital video cameras, smart wearable devices, smart weighing electronic scales, car displays, televisions or e-book readers, among which smart wearable devices can be, for example, smart bracelets, smart watches, virtual reality (VR) helmets, etc.

[0108] The present application is described in detail below through specific embodiments. The following embodiments are only partial embodiments of the present application and are not limitations of the present application.

[0109] Example 1

[0110] A glass substrate having an ITO first electrode 10 with a thickness of 50 nm is provided, and the substrate is sequentially placed in detergent, deionized water, acetone, ethanol, and deionized water, and each is ultrasonicated for 15 minutes, and then dried at 100° C.;

[0111] In a glove box, spin-coat PEDOT:PSS material on the first electrode 10 and anneal at 150° C. for 15 min to obtain a hole injection layer 60 with a thickness of 30 nm;

[0112] Spin coating TFB material on the hole injection layer 60, annealing at 150°C for 30 minutes to obtain a hole transport layer 50 with a thickness of 25 nm;

[0113] Spin-coat CdZnSe / ZnSe / ZnS quantum dot material on the hole transport layer 50, and anneal at 100°C for 5 minutes to obtain a light-emitting layer 40 with a thickness of 15 nm;

[0114] Commercial P25 white titanium dioxide (model: 637254; manufacturer: Sigma) was provided, and annealed at 300° C. for 5 h in a hydrogen atmosphere to obtain black titanium dioxide, and the black titanium dioxide was dissolved in ethanol to obtain a dispersion, and the dispersion was spin-coated on the light-emitting layer 40, and annealed at 80° C. for 10 min to obtain a charge functional layer 20 with a thickness of 30 nm;

[0115] Ag is evaporated on the charge functional layer 20 to obtain a cathode with a thickness of 100 nm;

[0116] After packaging, the optoelectronic device 100 is obtained.

[0117] Example 2

[0118] This embodiment is substantially the same as Embodiment 1, except that, in this embodiment, the annealing temperature during the preparation of black titanium dioxide is 100°C.

[0119] Example 3

[0120] This embodiment is substantially the same as Embodiment 1, except that, in this embodiment, the annealing temperature during the preparation of black titanium dioxide is 500°C.

[0121] Example 4

[0122] This embodiment is substantially the same as Embodiment 1, except that, in this embodiment, the annealing temperature during the preparation of black titanium dioxide is 1000°C.

[0123] Example 5

[0124] This embodiment is substantially the same as Embodiment 1, except that, in this embodiment, the annealing temperature during the preparation of black titanium dioxide is 80°C.

[0125] Example 6

[0126] This embodiment is substantially the same as Embodiment 1, except that, in this embodiment, the annealing temperature during the preparation of black titanium dioxide is 1200°C.

[0127] Example 7

[0128] This embodiment is basically the same as Embodiment 1, except that, in this embodiment, the annealing temperature during the preparation of black titanium dioxide is 1 h.

[0129] Example 8

[0130] This embodiment is basically the same as Embodiment 1, except that, in this embodiment, the annealing temperature during the preparation of black titanium dioxide is 36 h.

[0131] Example 9

[0132] This embodiment is basically the same as Embodiment 1, except that, in this embodiment, the annealing temperature during the preparation of black titanium dioxide is 72 h.

[0133] Example 10

[0134] This embodiment is basically the same as Embodiment 1, except that, in this embodiment, the annealing time for preparing black titanium dioxide is 0.5 h.

[0135] Embodiment 11

[0136] This embodiment is basically the same as Embodiment 1, except that, in this embodiment, the annealing time for preparing black titanium dioxide is 96 hours.

[0137] Comparative Example 1

[0138] This comparative example is substantially the same as Example 1, except that the titanium dioxide in this comparative example is the white titanium dioxide in Example 1.

[0139] The current efficiency CE and lifespan T95@1000nit tests were performed on the photoelectric devices of Examples 1 to 11 and Comparative Example 1. The test results are shown in Table 1.

[0140] The CE test method is: calculated by testing with Keithley 2400 high-precision digital source meter, Ocean Optic USB2000+ spectrometer and LS-160 brightness meter;

[0141] The test method for life span T95@1000nit is: in CDA gas, under constant current or voltage drive, measure the time taken for the device brightness to decay to a certain proportion of the maximum brightness, and the time taken for the brightness to decay to 95% of the maximum brightness is defined as T95, and this life span is the measured life span. In order to shorten the life span test cycle, the device life span test is usually carried out at high brightness by accelerating device aging, and the life span at low brightness is obtained by fitting the decay fitting formula. For example, the life span at 1000nits is recorded as T95@1000nits, and the calculation formula is:

[0142]

[0143] Among them, T95 L The 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. The constant current is 2mA.

[0144] The charge functional layer of Examples 1 to 11 and Comparative Example 1 was tested for electron mobility, and the test results are shown in Table 1. The test method is: 12 ITO electrodes are provided, and the light-emitting layers and charge functional layers of Examples 1 to 11 and Comparative Examples 1 to 2 are prepared on the 12 ITO electrodes, respectively, and then Ag electrodes are evaporated on the charge functional layers to obtain a semi-device (single electron transport thin film device EOD), and the current density-voltage curve of the semi-device is tested to obtain the space charge limited current (SCLC) region in the current density-voltage curve, and then according to the formula J = (9 / 8)ε r ε 0 μe V 2 / d 3 Calculate the electron mobility, where J represents the current density in mAcm -2 ; ε r represents the relative dielectric constant, ε 0 represents the dielectric constant of vacuum; μ e represents the hole mobility in cm 2 V -1 s -1 ; V represents the driving voltage, the unit is V; d represents the film thickness, the unit is m.

[0145] XPS test was performed on the black titanium dioxide of Examples 1 to 11 and the white titanium dioxide of Comparative Example 1 to detect Ti on the surface of the black titanium dioxide particles and the white titanium dioxide particles. 3+ The molar percentage of the test results is shown in Table 1.

[0146] The XPS test method is: using MgKa as the X-ray radiation source to perform XPS test on the black titanium dioxide particles, wherein the photon energy is 1253.6 eV, the voltage is 12.5 KV, the current is 16 mA, and the charging effect on the surface of the black titanium dioxide particles is calibrated with C1s.

[0147] Table 1:

[0148]

[0149]

[0150] From Table 1 we can see that:

[0151] No Ti was detected in the white titanium dioxide of Comparative Example 1. 3+ Ti was detected in the black titanium dioxide of Examples 1 to 4 and 6 to 11. 3+ Ti was not detected in Example 5 3+ The reason is that the annealing temperature of the black titanium dioxide in Example 5 is low, and the Ti 3+ Little or no Ti is generated 3+ The annealing temperature of Example 2 is relatively low, and the annealing time of Examples 7 and 10 is relatively short, resulting in the generation of Ti 3+ less.

[0152] Compared with the charge functional layer of comparative example 1, the charge functional layers of embodiments 1 to 4 and 7 to 9 have higher electron mobility; compared with the optoelectronic device of comparative example 1, the optoelectronic devices of embodiments 1 to 4 and 7 to 9 have higher luminous efficiency and longer life. It can be seen that compared with white titanium dioxide, black titanium dioxide particles as charge functional layers have higher electron mobility, which may be because the surface of black titanium dioxide particles has trivalent titanium, which has better energy level matching with the light-emitting layer, so that the optoelectronic device has higher luminous efficiency and longer life.

[0153] Compared with the charge functional layers of Examples 1 to 4, the charge functional layers of Examples 5 and 10 have lower electron mobility; compared with the optoelectronic devices of Examples 1 to 4, the optoelectronic devices of Examples 5 and 10 have higher luminous efficiency and longer life. The reason may be that the annealing temperature during the preparation of the black titanium dioxide particles of Example 5 is lower, while the annealing time during the preparation of the black titanium dioxide particles of Example 10 is shorter, resulting in less trivalent titanium on the surface of the black titanium dioxide particles.

[0154] Compared with the charge functional layers of Examples 1 and 7 to 9, the charge functional layers of Examples 6 and 11 have higher electron mobility. The reason may be that the annealing temperature during the preparation of the black titanium dioxide in Example 6 is higher, and the annealing time during the preparation of the black titanium dioxide in Example 11 is longer, resulting in more trivalent titanium on the surface of the prepared black dioxide particles. Although the increase in trivalent titanium can improve electron mobility, the conversion of tetravalent titanium into trivalent titanium will lead to more surface defects of the black titanium dioxide, and the more trivalent titanium, the more surface defects. The increase in defects will cause exciton recombination, thereby affecting the luminescence efficiency and lifespan of the optoelectronic device, resulting in the optoelectronic devices of Examples 6 and 10 having significantly lower luminescence efficiency and significantly shorter lifespan.

[0155] The optoelectronic devices and their 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 technical personnel 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 a first electrode, a charge functional layer, and a second electrode stacked in sequence, and further comprising a light-emitting layer located between the first electrode and the charge functional layer or between the second electrode and the charge functional layer, characterized in that: The material of the charge functional layer includes black titanium dioxide particles.

2. The optoelectronic device according to claim 1, characterized in that The titanium ions in the black titanium dioxide particles include Ti 4+ and Ti 3+ , where Ti 3+ The molar fraction in titanium ions is 0.1 to 50%.

3. The optoelectronic device according to claim 2, characterized in that Ti 3+ The molar fraction of titanium ions is 15 to 25%.

4. The optoelectronic device according to claim 1, characterized in that The material of the charge functional layer is composed of the black titanium dioxide particles.

5. The optoelectronic device according to claim 1, wherein: The average particle size of the black titanium dioxide particles is in the range of 1 to 10 nm; and / or The thickness of the charge functional layer is in the range of 20 to 150 nm.

6. The optoelectronic device according to claim 1, wherein: The first electrode and the second electrode independently include a doped metal oxide particle electrode, a composite electrode, a graphene electrode, a carbon nanotube electrode, a metal single substance electrode or an alloy electrode, the material of the doped metal oxide particle electrode includes 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 includes one or more of 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 or ZnS / Al / ZnS, and the material of the metal single substance electrode includes one or more of Ag, Al, Cu, Mo, Au, Pt, Ca, Mg and Ba; and / or The material of the light-emitting layer is an organic light-emitting material or a quantum dot light-emitting material, and the organic light-emitting material includes one or more of 4,4'-bis(N-carbazole)-1,1'-biphenyl:tri[2-(p-tolyl)pyridine iridium(III), 4,4',4"-tri(carbazole-9-yl)triphenylamine:tri[2-(p-tolyl)pyridine iridium, diaromatic anthracene derivatives, distilbene aromatic derivatives, pyrene derivatives, fluorene derivatives, TBPe fluorescent materials, TTPX fluorescent materials, TBRb fluorescent materials, DBP fluorescent materials, delayed fluorescent materials, TTA materials, thermally activated delayed materials, polymers containing BN covalent bonds, hybrid localized charge transfer excited state materials, exciplex light-emitting materials, polyacetylene and its derivatives, polyparaphenylene and its derivatives, polythiophene and its derivatives, polyfluorene and its derivatives;The quantum dot luminescent material includes one or more 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 independently selected from one or more of II-VI group compounds, IV-VI group compounds, III-V group compounds and I-III-VI group compounds. The II-VI group compounds include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, Zn STe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe, and the IV-VI group compound includes SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, One or more of PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe, the III-V group compound includes 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 As, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs and InAlPSb, the I-III-VI group compound includes one or more of CuInS2, CuInSe2 and AgInS2; the perovskite semiconductor material includes a doped or undoped inorganic perovskite semiconductor or an organic-inorganic hybrid perovskite semiconductor, and the general structural formula of the inorganic perovskite semiconductor is AMX3, wherein A is Cs; + ions, M is a divalent metal cation, including Pb 2 + Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ One or more of, X is a halogen anion, including Cl - Br - ,I - One or more of; the general structural formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, wherein B is an organic amine cation, including CH3(CH2) n-2 NH3 + or [NH3(CH2) n NH3] 2+ , where n≥2, M is a divalent metal cation, including Pb 2+ Sn 2+ , Cu 2+ 、Ni 2+ 、Cd 2+ Cr 2+ , Mn 2+ 、Co 2+ , Fe 2+ ,Ge 2+ , Yb 2+ 、Eu 2+ One or more of, X is a halogen anion, including Cl - Br - ,I - One or more of; and / or The photoelectric device also includes a hole transport layer located on a side of the light-emitting layer away from the charge functional layer, and the material of the hole transport layer includes 4,4'-N,N'-dicarbazolyl-biphenyl, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine], 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, poly(N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine), N,N'- Bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, 4,4',4'-tri(N-carbazolyl)-triphenylamine, 4,4',4'-tri(N-3-methylphenyl-N-phenylamino)triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))], poly(N-vinylcarbazole) and its derivatives, N,N'-di(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl- 4-4'-diamine, spiro NPB, poly(phenylene vinylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene, 4,4'-cyclohexylbis[N,N-di(4-methylphenyl)aniline], 1,3-bis(carbazol-9-yl)benzene, polyaniline, polypyrrole, poly(p-)phenylene vinylene, aromatic tertiary amines, polynuclear aromatic tertiary One or more of amines, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compounds, N,N,N',N'-tetraarylbenzidine, PEDOT:PSS and its derivatives, polymethacrylates and their derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, doped graphene, undoped graphene, C60, doped or undoped NiO, doped or undoped MoO3, doped or undoped WO3, doped or undoped V2O5, doped or undoped P-type gallium nitride, doped or undoped CrO3, doped or undoped CuO; and / or The photoelectric device also includes a hole injection layer located on a side of the light-emitting layer away from the charge functional layer, and the material of the hole injection layer includes one or more of 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, PEDOT, PEDOT:PSS, a derivative of PEDOT:PSS doped with s-MoO3, 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, tetracyanoquinodimethane, copper phthalocyanine, nickel oxide, molybdenum oxide, tungsten oxide, vanadium oxide, molybdenum sulfide, tungsten sulfide and copper oxide.

7. A method for preparing a photoelectric device, characterized in that: include: Providing a photovoltaic device preform, wherein the photovoltaic device preform comprises a first electrode; Providing black titanium dioxide, and disposing the black titanium dioxide on the photovoltaic device preform to obtain a charge functional layer; A second electrode is formed on a surface of the charge functional layer away from the first electrode to obtain a photoelectric device.

8. The preparation method according to claim 7, characterized in that: The optoelectronic device preform further includes a light-emitting layer disposed on the first electrode; or The forming of the second electrode on the charge functional layer comprises: sequentially forming a stacked light emitting layer and a second electrode on the charge functional layer.

9. The preparation method according to claim 7, characterized in that: The method for arranging the black titanium dioxide on the photoelectric device preform comprises: dissolving the black titanium dioxide in a first solvent to obtain a dispersion, arranging the dispersion on the photoelectric device preform, and annealing.

10. The preparation method according to claim 9, characterized in that: In the dispersion, the concentration of the black titanium dioxide is 5 to 100 mg / mL; and / or The first solvent includes an alcohol solvent, and the alcohol solvent includes one or more of methanol, ethanol, isopropanol, and ethylene glycol; and / or The annealing temperature is 80-120° C.; and / or The annealing time is 5 to 60 minutes.

11. The preparation method according to claim 7, characterized in that: The preparation method of the black titanium dioxide comprises: Provides white titanium dioxide particles; The white titanium dioxide particles are placed in a reducing atmosphere and heat treated at 100 to 1000° C. for 1 to 72 hours to obtain black titanium dioxide particles.

12. The preparation method according to claim 7, characterized in that: The photoelectric device preform further comprises a hole transport layer and a light emitting layer sequentially stacked on the first electrode; or The forming of the second electrode on the charge functional layer comprises: sequentially forming a stacked light emitting layer, a hole transport layer and a second electrode on the charge functional layer; or The photoelectric device preform further comprises a hole injection layer, a hole transport layer and a light emitting layer sequentially stacked on the first electrode; or The forming of the second electrode on the charge functional layer comprises: sequentially forming a light emitting layer, a hole transport layer, a hole injection layer and a second electrode stacked on the charge functional layer.

13. A display device, characterized in that: The display device comprises the optoelectronic device according to any one of claims 1 to 6, or the display device comprises the optoelectronic device prepared by the preparation method according to any one of claims 7 to 12.

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