CN117693213A - Photoelectric device, preparation method of photoelectric device and electronic equipment - Google Patents

Photoelectric device, preparation method of photoelectric device and electronic equipment Download PDF

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CN117693213A
CN117693213A CN202211028104.4A CN202211028104A CN117693213A CN 117693213 A CN117693213 A CN 117693213A CN 202211028104 A CN202211028104 A CN 202211028104A CN 117693213 A CN117693213 A CN 117693213A
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quantum dot
emitting layer
layer
dot light
bottom electrode
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王华民
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TCL Technology Group Co Ltd
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TCL Technology Group Co Ltd
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Abstract

The application discloses an optoelectronic device, a preparation method of the optoelectronic device and electronic equipment, wherein the optoelectronic device comprises: the anode and the cathode which are oppositely arranged, and the first quantum dot luminescent layer which is arranged between the anode and the cathode, wherein the material of the first quantum dot luminescent layer comprises first quantum dots and first materials, one side of the first quantum dot luminescent layer, which is close to the cathode, is provided with second materials, the first materials are ionic liquids, the conductivity of the second materials is lower than that of the first materials, and the electron-hole transmission balance is effectively promoted, so that the luminous efficiency and the service life of a photoelectric device are improved, the photoelectric device is applied to electronic equipment, and the photoelectric performance and the service life of the electronic equipment are improved.

Description

Photoelectric device, preparation method of photoelectric device and electronic equipment
Technical Field
The application relates to the technical field of photoelectricity, in particular to a photoelectric device, a preparation method of the photoelectric device and electronic equipment.
Background
Quantum Dots (QDs), also known as semiconductor nanocrystals, are nanocrystals with a radius that is less than or near the bohr radius of an exciton, typically between 1nm and 20nm in size. The quantum dot has unique fluorescent nanometer effect, the luminous wavelength of the quantum dot can be regulated and controlled by changing the size and the composition of components, and the quantum dot has the advantages of narrow half-peak width of a luminous spectrum, high color purity, good light stability, wide excitation spectrum and controllable emission spectrum, and has wide application prospect in the technical fields of photovoltaic power generation, photoelectric display, biological probes and the like.
In the technical field of photoelectric display, a quantum dot light emitting diode (Quantum Dot Light Emitting Diode, QLED) is a photoelectric device based on quantum dots as a luminescent material, and the quantum dots are typical inorganic matters and have good stability, so that the quantum dots can make up the defects of easy ageing and easy corrosion of an organic luminescent material, thereby being beneficial to prolonging the service life of the photoelectric device, and therefore, the luminescent display technology based on the QLED is the novel display technology with the current most potential. The QLED technology has been developed for over 20 years, and has a huge progress in terms of performance index, and also has a huge application development potential, but at present, there are still disadvantages, such as a problem of unbalanced carrier injection, that is, an electron injection level is greater than a hole injection level, so that the luminous efficiency and the service life of the QLED are poor. Therefore, there is a need to improve the problem of carrier injection imbalance to increase the luminous efficiency and lifetime of QLEDs.
Disclosure of Invention
The application provides an optoelectronic device, a preparation method of the optoelectronic device and electronic equipment, so as to solve the problem of unbalanced carrier injection of the optoelectronic device.
The technical scheme of the application is as follows:
In a first aspect, the present application provides an optoelectronic device comprising:
an anode;
a cathode disposed opposite the anode; and
the first quantum dot light-emitting layer is arranged between the anode and the cathode;
the material of the first quantum dot light-emitting layer comprises first quantum dots and first materials, and a second material is arranged on one side, close to the cathode, of the first quantum dot light-emitting layer;
the first material is an ionic liquid, and the second material has a conductivity lower than that of the first material.
Optionally, the material of the first quantum dot light emitting layer is composed of the first quantum dot and the first material.
Optionally, an interface modification layer is disposed between the first quantum dot light emitting layer and the cathode, and the second material forms the interface modification layer. Optionally, the thickness of the interface modification layer is 3nm to 6nm.
Optionally, in the first quantum dot light emitting layer, the first quantum dot: the mass ratio of the first material is 1: (20-40);
and/or the thickness of the first quantum dot light-emitting layer is 10nm to 15nm;
and/or the difference between the conductivity of the first material and the conductivity of the second material is 0.2mS/cm to 0.8mS/cm.
Optionally, the cation of the first material is selected from alkyl quaternary ammonium ions, alkyl quaternary phosphonium ions, alkyl substituted imidazole ions, or alkyl substituted pyridine ions;
and/or the anions of the first material are selected from at least one of halogen ions or acid ions.
Optionally, the alkyl quaternary ammonium ion is selected from one of N, N-diethyl-N-methyl-N- (N-propyl) ammonium cation or N, N-diethyl-N-methyl- (2-methoxyethyl) ammonium cation;
and/or the alkyl quaternary phosphonium ion is selected from one of tetradecyl tributyl phosphonium cation, tetrahydroxymethyl phosphonium cation, ethyl tributyl phosphonium cation or tetrabutyl phosphonium cation;
and/or the alkyl-substituted imidazole ion is selected from one of 1-butyl-3-methylimidazole cation, 1-ethyl-3-methylimidazole cation, 1-octyl-3-methylimidazole cation, 1-decyl-3-methylimidazole cation, 1-hexyl-3-methylimidazole cation or 1-methyl-3-n-octylimidazole cation;
and/or the alkyl-substituted pyridine ion is selected from at least one of 1-butyl-4-methylpyridine ion, 1-hexyl-4-methylpyridine ion, N-ethylpyridine ion, N-butylpyridine ion, N-hexylpyridine ion, N-octylpyridine ion, or N-methyl-N-propylpyridine ion;
And/or, the halogen ionSelected from F - 、Cl - 、Br - Or I - At least one of (a) and (b);
and/or the acid radical ion is selected from BF 4 - 、PF 6 - 、CF 3 SO 3- 、CF 3 COO - 、(CF 3 SO 2 ) 3 C - 、(C 2 F 5 SO 2 ) 3 C - 、(CF 3 SO 2 ) 2 N - 、C 3 F 7 COO - 、C 4 F 9 SO 3 - 、(C 2 F 5 SO 2 ) 2 N - 、SbF 6 - 、AsF 6 - 、CB 11 H 12 - 、NO 2 - 、NO 3 - 、ClO 4 - Or C 8 H 17 SO 4 - At least one of them.
Alternatively, the first material is selected from the group consisting of 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium bistrifluoromethanesulfonimide salt, 1-octyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium chloride, 1-decyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazole bis (pentafluoroethylsulfonyl) imide, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-methyl-3-N-octylimidazole tetrafluoroborate, 1-ethyl-3-methylimidazole dicyandiamide, N-diethyl-N-methyl-N- (N-propyl) trifluoromethyl trifluoroammonium borate, 1-butyl-3-methylimidazolium triflate, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium bistrifluoromethylsulfonyl) imide and N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium bistrifluoromethylsulfonyl imide, 1-methyl-4-bromopyridine, and quaternary ammonium salts thereof, at least one of 1-hexyl-4-methylpyridine bromide, 1-butyl-4-methylpyridine tetrafluoroborate or 1-butyl-4-methylpyridine hexafluorophosphate.
Optionally, the optoelectronic device further comprises an electronic functional layer, and the electronic functional layer is arranged between the cathode and the first quantum dot light-emitting layer; the electron functional layer comprises an electron transport layer and/or an electron injection layer, and for the electron functional layer comprising the electron transport layer and the electron injection layer, the electron transport layer is closer to the first quantum dot light emitting layer than the electron injection layer, and the electron injection layer is closer to the cathode than the electron transport layer;
wherein the material of the electron transport layer comprises metal oxide selected from ZnO and TiO 2 、SnO 2 、BaO、Ta 2 O 3 、ZrO 2 At least one of TiLiO, znGaO, znAlO, znMgO, znSnO, znLiO, inSnO, alZnO, znOCl, znOF or ZnMgLiO;
and/or the material of the electron injection layer includes at least one of an alkali metal halide, an alkali metal organic complex, or an organic phosphine compound selected from at least one of an organic phosphorus oxide, an organic thiophosphine compound, or an organic selenophosphine compound.
Optionally, the optoelectronic device further includes a hole functional layer disposed between the first quantum dot light emitting layer and the anode, the hole functional layer including a hole injection layer and/or a hole transport layer, the hole injection layer being closer to the anode than the hole transport layer, the hole transport layer being closer to the first quantum dot light emitting layer than the hole injection layer for the hole functional layer including the hole injection layer and the hole transport layer;
The hole injection layer is made of poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonic acid), copper phthalocyanine, titanyl phthalocyanine, 4 '-tris (N-3-methylphenyl-N-phenylamino) triphenylamine, 4' -tris [ 2-naphthylphenylamino ] amine]At least one of triphenylamine, 2,3,5, 6-tetrafluoro-7, 7', 8' -tetracyanodimethyl-p-benzoquinone, 2,3,6,7,10, 11-hexacyano-1, 4,5,8,9, 12-hexaazabenzophenanthrene, transition metal oxide or transition metal chalcogenide, the transition metal oxide being selected from Ni O x 、MoO x 、WO x 、CrO x Or CuO x At least one of the above-mentioned materials,the transition metal chalcogenide is selected from MoS x 、MoSe x 、WS x 、WSe x Or CuS x At least one of (a) and (b);
and/or the material of the hole transport layer is selected from poly (9, 9-dioctylfluorene-CO-N- (4-butylphenyl) diphenylamine), 3-hexyl substituted polythiophene, poly (9-vinylcarbazole), poly [ bis (4-phenyl) (4-butylphenyl) amine]Poly (N, N '-bis (4-butylphenyl) -N, N' -diphenyl-1, 4-phenylenediamine-CO-9, 9-dioctylfluorene), 4',4 "-tris (carbazol-9-yl) triphenylamine, 4' -bis (9-carbazol) biphenyl, N '-diphenyl-N, N' -bis (3-methylphenyl) -1,1 '-biphenyl-4, 4' -diamine, N '-diphenyl-N, N' - (1-naphthyl) -1,1 '-biphenyl-4, 4' -diamine, poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonic acid), doped or undoped graphene, C60, niO, moO3, WO 3 、V 2 O 5 、CrO 3 At least one of CuO or P-type gallium nitride.
Optionally, the optoelectronic device further comprises: the second quantum dot light-emitting layer is arranged on one side, close to the cathode, of the first quantum dot light-emitting layer;
the material of the second quantum dot light-emitting layer comprises second quantum dots, and the second material is arranged between the first quantum dot light-emitting layer and the second quantum dot light-emitting layer;
for the photoelectric device with the electron function layer arranged between the cathode and the first quantum dot light-emitting layer, the second quantum dot light-emitting layer is arranged between the first quantum dot light-emitting layer and the electron function layer.
Optionally, the second material is a solvent that can disperse the first quantum dots and/or the second quantum dots;
and/or the thickness of the second quantum dot light-emitting layer is 10nm to 15nm;
and/or the luminous colors of the first quantum dots and the second quantum dots are the same.
Optionally, the second material is selected from at least one of n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, or n-undecane;
and/or the first quantum dot and the second quantum dot are the same.
Optionally, the first quantum dot or the second quantum dot is selected from at least one of single component quantum dots, core-shell structure quantum dots, inorganic perovskite quantum dots, or organic-inorganic hybrid perovskite quantum dots, independently of each other;
The material of the single component quantum dot, the material of the core-shell structure quantum dot and the material of the shell of the core-shell structure quantum dot are selected from at least one of II-VI compound, III-V compound, IV-VI compound or I-III-VI compound independently of each other, wherein the II-VI compound is selected from at least one 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 or HgZnSTe, the III-V 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, alNP, alNAs, alNSb, alPAs, alPSb, inNP, inNAs, inNSb, inPAs, inPSb, gaAlNP, gaAlNAs, gaAlNSb, gaAlPAs, gaAlPSb, gaInNP, gaInNAs, gaInNSb, gaInPAs, gaInPSb, inAlNP, inAlNAs, inAlNSb, inAlPAs or InAlPSb, the IV-VI 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 or SnPbSTe, the I-III-VI compound is selected from CuInS 2 、CuInSe 2 Or AgInS 2 At least one of (a) and (b);
and/or the materials of the anode and the cathode are selected from at least one of metal, carbon material or metal oxide independently of each other, the metal is selected from at least one of Al, ag, cu, mo, au, ba, ca or Mg, the carbon material is selected from at least one of graphite, carbon nanotube, graphene or carbon fiber, and the metal oxide is selected from at least one of indium tin oxide, fluorine doped tin oxide, tin antimony oxide, aluminum doped zinc oxide, gallium doped zinc oxide, indium doped zinc oxide or magnesium doped zinc oxide.
In a second aspect, the present application provides a method for preparing an optoelectronic device, including the steps of:
providing a prefabricated device comprising a bottom electrode;
applying a first quantum dot solution on one side of the bottom electrode, wherein the first quantum dot solution comprises first quantum dots and a first material, the first material is ionic liquid, and then drying to obtain a first quantum dot luminescent layer; and
forming a top electrode on one side of the first quantum dot light-emitting layer away from the bottom electrode;
the preparation method comprises the steps of forming a first quantum dot luminescent layer on one side of a substrate, forming a bottom electrode on the side of the substrate, forming a bottom electrode on the bottom electrode, forming a top electrode on the side of the first quantum dot luminescent layer, and forming a bottom electrode on the side of the substrate, wherein the photoelectric device is of a positive structure, the bottom electrode is an anode, the top electrode is a cathode, and the preparation method further comprises the steps of: forming a second material on one side of the first quantum dot light-emitting layer away from the bottom electrode, wherein the conductivity of the second material is lower than that of the first material; the second material is arranged between the first quantum dot light-emitting layer and the top electrode;
Or the photoelectric device is of an inverted structure, the bottom electrode is a cathode, the top electrode is an anode, and before the step of applying the first quantum dot solution on one side of the bottom electrode, the preparation method further comprises the steps of: forming a second material on one side of the bottom electrode, the second material having a conductivity lower than a conductivity of the first material; the second material is disposed between the first quantum dot light emitting layer and the bottom electrode.
Optionally, the optoelectronic device is a front-mounted structure, and the step of forming the second material on the side of the first quantum dot light-emitting layer away from the bottom electrode includes: applying a second material solution on one side of the first quantum dot light-emitting layer far away from the bottom electrode, and then drying to form a second material on one side of the first quantum dot light-emitting layer far away from the bottom electrode, wherein the second material at least covers part of one side of the first quantum dot light-emitting layer far away from the bottom electrode, and the temperature of the drying treatment is lower than the boiling point of the second material;
alternatively, the optoelectronic device is an inverted structure, and the step of forming the second material on one side of the bottom electrode includes: a second material solution is applied to one side of the bottom electrode, and then a drying process is performed to form the second material on one side of the bottom electrode, wherein the second material covers at least a portion of one side of the bottom electrode, and wherein the drying process is performed at a temperature lower than the boiling point of the second material.
Optionally, the photovoltaic device is in a front-mounted structure, after the step of forming the second material on the side of the first quantum dot light-emitting layer away from the bottom electrode, and before the step of forming the top electrode, the preparation method further includes the steps of: forming a second quantum dot light-emitting layer on one side of the first quantum dot light-emitting layer far away from the bottom electrode, wherein the material of the second quantum dot light-emitting layer comprises second quantum dots; the second material is positioned between the first quantum dot light-emitting layer and the second quantum dot light-emitting layer;
alternatively, the optoelectronic device is in an inverted structure, and before the step of forming the second material on one side of the bottom electrode, the preparation method further includes the steps of: and forming a second quantum dot light-emitting layer on one side of the bottom electrode, wherein the second material is formed on one side of the second quantum dot light-emitting layer away from the bottom electrode.
Optionally, the cation of the ionic liquid is selected from alkyl quaternary ammonium ions, alkyl quaternary phosphonium ions, alkyl substituted imidazole ions, or alkyl substituted pyridine ions;
and/or the anions of the ionic liquid are selected from at least one of halogen ions or acid radical ions;
And/or the ionic liquid has a boiling point of 60 ℃ to 80 ℃ at 760mm hg;
and/or the concentration of the first quantum dots in the first quantum dot solution is 20mg/mL to 40mg/mL;
and/or the difference between the conductivity of the first material and the conductivity of the second material is 0.2mS/cm to 0.8mS/cm;
and/or the second material is selected from at least one of n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane or n-undecane.
In a third aspect, the present application provides an electronic device comprising an optoelectronic device according to any one of the first aspects, or comprising an optoelectronic device manufactured according to any one of the manufacturing methods of the second aspects.
The application provides a photoelectric device, a preparation method of the photoelectric device and electronic equipment, and the photoelectric device has the following technical effects:
in the photoelectric device of the application, the material of the first quantum dot luminescent layer comprises ionic liquid, the ionic liquid has ideal conductivity, carrier transmission capacity of the photoelectric device can be effectively improved, a second material is arranged on one side, close to a cathode, of the first quantum dot luminescent layer, and the conductivity of the second material is lower than that of the first material, so that hole injection level is improved, electron injection is slowed down, matching degree of the hole injection level and the electron injection level is improved, electron-hole transmission balance is promoted, and luminous efficiency and service life of the photoelectric device are improved. In addition, the gap between the first quantum dots can be filled with ionic liquid, so that the density of the first quantum dot luminescent layer is improved, the two functional layers oppositely arranged on two sides of the first quantum dot luminescent layer are effectively prevented from being in direct contact, the problem of quenching carrier luminescence is solved, the surface flatness of the first quantum dot luminescent layer is improved, and the leakage current of the photoelectric device is effectively reduced.
In the preparation method of the photoelectric device, the ionic liquid is used as the solvent of the first quantum dot, the solution method is used for preparing the first quantum dot luminescent layer, and the second material is formed on one side of the first quantum dot luminescent layer, close to the cathode, so that electron-hole transmission balance of the photoelectric device can be promoted. In addition, in the film forming process of the first quantum dot luminescent layer, the ionic liquid can dynamically fill the pores between the adjacent quantum dots, so that the porosity and the surface roughness of the first quantum dot luminescent layer are effectively reduced, the surface flatness and the density of the first quantum dot luminescent layer are improved, the leakage current of the prepared photoelectric device is effectively reduced, the risk of direct contact between two functional layers relatively arranged on two sides of the first quantum dot luminescent layer in the prepared photoelectric device is reduced, the phenomenon of quenching carrier luminescence is improved, and in addition, the ionic liquid also has the function of passivating the surface defects of the first quantum dot, and has the advantages of simplicity and convenience in preparation and suitability for large-scale industrial production.
The photoelectric device or the photoelectric device manufactured by the manufacturing method is applied to electronic equipment, and is beneficial to improving the photoelectric performance and prolonging the service life of the electronic equipment.
Drawings
Technical solutions and other advantageous effects of the present application will be made apparent from the following detailed description of specific embodiments of the present application with reference to the accompanying drawings.
Fig. 1 is a schematic structural diagram of a first photoelectric device provided in an embodiment of the present application;
fig. 2 is a schematic structural diagram of a second photoelectric device provided in an embodiment of the present application;
fig. 3 is a schematic structural diagram of a third photovoltaic device provided in an embodiment of the present application;
fig. 4 is a schematic structural diagram of a fourth photovoltaic device provided in an embodiment of the present application;
fig. 5 is a schematic flow chart of a method for manufacturing an optoelectronic device according to an embodiment of the present application;
fig. 6 is a schematic structural diagram of a fourth photovoltaic device provided in an embodiment of the present application;
fig. 7 is an external quantum efficiency-current density characteristic diagram of the photovoltaic device in example 1, comparative example 1, and comparative example 2 in experimental examples of the present application.
Detailed Description
The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by those skilled in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In addition, any methods and materials similar or equivalent to those described herein can be used in the present invention. The preferred methods and materials described herein are illustrative only and should not be construed as limiting the scope of the present application.
The following description of the embodiments is not intended to limit the preferred embodiments. In addition, in the description of the present application, the term "comprising" means "including but not limited to". Various embodiments of the present application may exist in a range of forms; it should be understood that the description in a range format is merely for convenience and brevity and should not be construed as a rigid limitation on the scope of the invention; it is therefore to be understood that the range description has specifically disclosed all possible sub-ranges and individual values within that range. For example, it should be considered that a description of a range from 1 to 6 has 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 ranges, such as 1, 2, 3, 4, 5, and 6, wherever applicable. In addition, whenever a numerical range is referred to herein, it is meant to include any reference number (fractional or integer) within the indicated range.
The embodiment of the application provides a photoelectric device, as shown in fig. 1, the photoelectric device 1 includes an anode 11, a cathode 12 and a first quantum dot light-emitting layer 131, the anode 11 and the cathode 12 are oppositely arranged, the first quantum dot light-emitting layer 131 is arranged between the anode 11 and the cathode 12, wherein the material of the first quantum dot light-emitting layer 131 includes a first quantum dot and a first material, a second material 132 is arranged on one side of the first quantum dot light-emitting layer 131 close to the cathode, the first material is ionic liquid, and the conductivity of the second material is lower than that of the first material.
For the QLED, besides the problem of unbalanced carrier transmission, the formed quantum dot luminescent layer is of a loose porous structure based on the special morphology of the quantum dot, and the defect is that: first, the porous structure is unfavorable for the conduction of carriers; secondly, two functional layers oppositely arranged at two sides of the quantum dot luminous layer can be in direct contact at the gap, so that the problem of quenching carrier luminescence is caused; thirdly, the loose porous structure causes higher surface roughness of the quantum dot luminescent layer, so that the surface smoothness of the quantum dot luminescent layer is poor, thereby causing the increase of leakage current of the photoelectric device and causing adverse effects on the photoelectric performance and service life of the photoelectric device.
In the photoelectric device 1 of the embodiment of the present application, the material of the first quantum dot light-emitting layer 131 includes an ionic liquid, and the ionic liquid can fill the gap between the first quantum dots, so as to promote the density of the first quantum dot light-emitting layer 131, effectively avoid the direct contact of two functional layers oppositely disposed on two sides of the first quantum dot light-emitting layer 131, improve the problem of quenching carrier light emission, and improve the surface flatness of the first quantum dot light-emitting layer 131, and effectively reduce the leakage current of the photoelectric device 1. In addition, the ionic liquid has the characteristic of high conductivity, carrier transmission capability of the photoelectric device 1 can be effectively improved, and the second material 132 is arranged on one side, close to the cathode 12, of the first quantum dot light-emitting layer 131, and the conductivity of the second material 132 is lower than that of the first material, so that electron injection is slowed down while hole injection level is improved, matching degree of the hole injection level and the electron injection level is improved, electron-hole transmission balance is promoted, and light-emitting efficiency and service life of the photoelectric device 1 are further improved.
In some embodiments of the present application, the material of the first quantum dot light emitting layer 131 is composed of the first quantum dot and the first material.
In the optoelectronic device 1 of the embodiment of the present application, the second material 132 may cover a portion of the side of the first quantum dot light-emitting layer 131 near the cathode 12, for example, the second material 132 is distributed in an island shape on the side of the first quantum dot light-emitting layer 131 near the cathode 12. The second material 132 may also completely cover the side of the first quantum dot light emitting layer 131 near the cathode 12, for example, the second material 132 may completely cover the side of the first quantum dot light emitting layer 131 near the cathode 12 in the form of a film layer.
In order to further increase the matching degree between the hole injection level and the electron injection level, in some embodiments of the present application, with continued reference to fig. 1, an interface modification layer is disposed between the first quantum dot light emitting layer 131 and the cathode 12, and the second material 132 forms the interface modification layer. The thickness of the interface modification layer may be, for example, 3nm to 6nm, with 3nm, 4nm, 5nm, or 6nm being exemplified.
In order to both improve the surface flatness and compactness of the first quantum dot light emitting layer 131 and ensure that the first quantum dot light emitting layer has an ideal energy level structure, in some embodiments of the present application, the first quantum dots in the first quantum dot light emitting layer 131: the mass ratio of the first material is 1: (20 to 40), for example, may be 1: (20-25), 1: (25-30), 1: (30-35), or 1: (35-40), exemplified by 1: 20. 1: 30. or 1:40.
In some embodiments of the present application, the thickness of the first quantum dot light emitting layer 131 is 10nm to 15nm, which may be, for example, 10nm, 11nm, 12nm, 13nm, 14nm, or 15nm.
In some embodiments of the present application, the difference between the conductivity of the first material and the conductivity of the second material is 0.2mS/cm to 0.8mS/cm, which may be, for example, 0.2mS/cm, 0.3mS/cm, 0.4mS/cm, 0.5mS/cm, 0.6mS/cm, 0.7mS/cm, or 0.8mS/cm.
In some embodiments of the present application, the cation of the first material is selected from alkyl quaternary ammonium ions, alkyl quaternary phosphonium ions, alkyl substituted imidazole ions, or alkyl substituted pyridine ions. Wherein the alkyl quaternary ammonium ion includes, but is not limited to, one of N, N-diethyl-N-methyl-N- (N-propyl) ammonium cation or N, N-diethyl-N-methyl- (2-methoxyethyl) ammonium cation. Alkyl quaternary phosphonium ions include, but are not limited to, one of tetradecyl tributyl phosphonium cation, tetrahydroxymethyl phosphonium cation, ethyl tributyl phosphonium cation, or tetrabutyl phosphonium cation. The alkyl substituted imidazole ion includes, but is not limited to, one of 1-butyl-3-methylimidazole cation, 1-ethyl-3-methylimidazole cation, 1-octyl-3-methylimidazole cation, 1-decyl-3-methylimidazole cation, 1-hexyl-3-methylimidazole cation, or 1-methyl-3-n-octylimidazole cation. Alkyl substituted pyridine ions include, but are not limited to, at least one of 1-butyl-4-methylpyridine ion, 1-hexyl-4-methylpyridine ion, N-ethylpyridine ion, N-butylpyridine ion, N-hexylpyridine ion, N-octylpyridine ion, or N-methyl-N-propylpyridine ion.
In order to lower the hole injection barrier to further increase the hole injection level of the photovoltaic device, the cation of the first material is selected, for example, from alkyl substituted pyridine ions.
In some embodiments of the present application, the anion of the first material is selected from at least one of a halide ion or an acid ion. Wherein the halogen ion includes but is not limited to F - 、Cl - 、Br - Or I - At least one of the acid ions including but not limited to BF 4 - 、PF 6 - 、CF 3 SO 3- 、CF 3 COO - 、(CF 3 SO 2 ) 3 C - 、(C 2 F 5 SO 2 ) 3 C - 、(CF 3 SO 2 ) 2 N - 、C 3 F 7 COO - 、C 4 F 9 SO 3 - 、(C 2 F 5 SO 2 ) 2 N - 、SbF 6 - 、AsF 6 - 、CB 11 H 12 - 、NO 2 - 、NO 3 - 、ClO 4 - Or C 8 H 17 SO 4 - At least one of them.
In some embodiments of the present application, the first material is selected from the group consisting of 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium bistrifluoro methanesulfonimide salt, 1-octyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium chloride, 1-decyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazole bis (pentafluoroethylsulfonyl) imide, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-methyl-3-N-octylimidazole tetrafluoroborate, 1-ethyl-3-methylimidazole dicyandiamide, N-diethyl-N-methyl-N- (N-propyl) trifluoromethyl trifluoroammonium borate, 1-butyl-3-methylimidazolium triflate, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium bistrifluoromethylsulfonyl) imide and N, N-diethyl-N- (2-methoxyethyl) ammonium bistrifluoro methylsulfonyl) imide, 1-hexyl-3-methylimidazole tetrafluoroborate, 1-methyl-4-methyl-pyridinium bromide, and quaternary ammonium salts thereof, at least one of 1-hexyl-4-methylpyridine bromide, 1-butyl-4-methylpyridine tetrafluoroborate or 1-butyl-4-methylpyridine hexafluorophosphate.
In the photovoltaic device 1 of the embodiment of this application, the materials of the anode 11 and the cathode 12 are selected from at least one of metal, carbon material, or metal oxide independently of each other, and the metal is selected from at least one of Al, ag, cu, mo, au, ba, ca or Mg; the carbon material is at least one of graphite, carbon nano tube, graphene or carbon fiber; the metal oxide may be a doped or undoped metal oxide, for example, at least one selected from Indium Tin Oxide (ITO), fluorine doped tin oxide (FTO), tin antimony oxide (ATO), aluminum doped zinc oxide (AZO), gallium doped zinc oxide (GZO), indium doped zinc oxide (IZO) or magnesium doped zinc oxide (MZO). Anode 11 or cathode 12 may also be selected from a composite electrode of doped or undoped transparent metal oxide sandwiching a metal, the composite electrode including but not limited to 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、TiO 2 /Ag/TiO 2 Or TiO 2 /Al/TiO 2 At least one of them. The thickness of the anode 11 may be, for example, 20nm to 200nm, and the thickness of the cathode 12 may be, for example, 20nm to 200nm.
The first quantum dot is selected from at least one of single component quantum dot, core-shell structure quantum dot, inorganic perovskite quantum dot or organic-inorganic hybrid perovskite quantum dot, and the average particle diameter of the first quantum dot may be, for example, 5nm to 10nm, and exemplified by 5nm, 6nm, 7nm, 8nm, 9nm or 10nm.
For a single groupComponent quantum dots and core-shell structure quantum dots, material of single component quantum dots, material of core-shell structure quantum dots, or material of shell of core-shell structure quantum dots including but not limited to at least one of II-VI compound 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 or HgZnSTe, III-VI compound 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, gaAlNAs, gaAlNSb, gaAlPAs, gaAlPSb, gaInNP, gaInNAs, gaInNSb, gaInPAs, gaInPSb, inAlNP, inAlNAs, inAlNSb, inAlPAs or InAlPSb, IV-VI compound selected from SnS, snSe, snTe, pbS, pbSe, pbTe, snSeS, snSeTe, snSTe, pbSeS, pbSeTe, pbSTe, snPbS, snPbSe, snPbTe, snPbSSe, snPbSeTe or SnPbSTe, I-III-VI compound selected from CuInS 2 、CuInSe 2 Or AgInS 2 At least one of them.
For the inorganic perovskite quantum dots, the structural general formula of the inorganic perovskite quantum dots is AMX 3 Wherein A is Cs + Ion, M is a divalent metal cation, M includes but is not limited to Pb 2+ 、Sn 2+ 、Cu 2+ 、Ni 2+ 、Cd 2+ 、Cr 2+ 、Mn 2+ 、Co 2+ 、Fe 2+ 、Ge 2+ 、Yb 2+ Or Eu 2+ X is a halogen anion including but not limited to Cl - 、Br - Or I -
For the organic-inorganic hybrid perovskite quantum dots, the structural general formula of the organic-inorganic hybrid perovskite quantum dots is BMX 3 Wherein B is an organic amine cation, including but not limited toThus CH 3 (CH 2 ) n -2NH 3+ (n.gtoreq.2) or NH 3 (CH 2 ) n NH 3 2+ (n.gtoreq.2), M is a divalent metal cation, M includes but is not limited to Pb 2+ 、Sn 2+ 、Cu 2+ 、Ni 2+ 、Cd 2+ 、Cr 2+ 、Mn 2+ 、Co 2+ 、Fe 2+ 、Ge 2+ 、Yb 2+ Or Eu 2+ X is a halogen anion including but not limited to Cl - 、Br - Or I -
It is understood that the surface of the first quantum dot may further have a ligand attached thereto, the ligand including, but not limited to, at least one of amine ligands, carboxylic acid ligands, thiol ligands, at least one of (oxy) phosphine ligands, phospholipids, soft phospholipids or polyvinylpyridines, the amine ligands being selected from at least one of oleylamine, n-butylamine, n-octylamine, octaamine, 1, 2-ethylenediamine or octadecylamine, the carboxylic acid ligands being selected from at least one of oleic acid, acetic acid, butyric acid, valeric acid, caproic acid, arachidic acid, decanoic acid, undecylenic acid, tetradecanoic acid or stearic acid, the thiol ligands being selected from at least one of ethanethiol, propanethiol, mercaptoethanol, benzenethiol, octanethiol, dodecyl mercaptan or octadecyl thiol, the (oxy) phosphine ligand being selected from at least one of trioctylphosphine or trioctylphosphine.
In order to further improve the light emitting efficiency and the service life of the optoelectronic device 1, in some embodiments of the present application, as shown in fig. 2, the optoelectronic device 1 further includes a second quantum dot light emitting layer 133, the second quantum dot light emitting layer 133 is disposed on a side of the first quantum dot light emitting layer 131 near the cathode 12, wherein a material of the second quantum dot light emitting layer 133 includes a second quantum dot, and the second material 132 is disposed between the first quantum dot light emitting layer 131 and the second quantum dot light emitting layer 133. The selection type range of the second quantum dots is the same as the selection type range of the first quantum dots.
In some embodiments of the present application, the material of the second quantum dot light emitting layer 133 is a second quantum dot.
In some embodiments of the present application, the second material 132 is a solvent that can disperse the first quantum dots and/or the second quantum dots. The second material 132 includes, but is not limited to, at least one of n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, or n-undecane.
In some embodiments of the present application, the thickness of the second quantum dot light emitting layer 133 is 10nm to 15nm, and the thickness of the second quantum dot light emitting layer 133 is 10nm to 15nm, which may be, for example, 10nm, 11nm, 12nm, 13nm, 14nm, or 15nm.
In some embodiments of the present application, the luminescent colors of the first quantum dots and the second quantum dots are the same. The first quantum dot and the second quantum dot may be the same or different.
To further facilitate electron-hole transport balance, in some embodiments of the present application, the carrier transport rate of the first quantum dot light emitting layer 131 is higher than the carrier transport rate of the second quantum dot light emitting layer 133.
In some embodiments of the present application, the first quantum dot light emitting layer 131 has a lower porosity than the second quantum dot light emitting layer 133.
In order to further enhance the optoelectronic performance and the service life of the optoelectronic device, in some embodiments of the present application, as shown in fig. 3, the optoelectronic device 1 further includes an electronic functional layer 14, where the electronic functional layer 14 is disposed between the cathode 12 and the first quantum dot light emitting layer 131. The electron functional layer 14 includes an electron transport layer and/or an electron injection layer, and for an electron functional layer including an electron transport layer and an electron injection layer, the electron transport layer is closer to the first quantum dot light emitting layer 131 than the electron injection layer, and the electron injection layer is closer to the cathode 12 than the electron transport layer. The thickness of the electron functional layer 14 is, for example, 10nm to 200nm.
With continued reference to fig. 3, for the optoelectronic device 1 including the second quantum dot light emitting layer 133, the electron functional layer 14 is disposed between the second quantum dot light emitting layer 133 and the cathode 12, and the second material 132 is disposed between the first quantum dot light emitting layer 131 and the second quantum dot light emitting layer 133.
In some embodiments of the present application, the material of the electron transport layer comprises a metal oxide, which may be undopedOr doped metal oxides, for example selected from ZnO, tiO 2 、SnO 2 、BaO、Ta 2 O 3 、ZrO 2 At least one of TiLiO, znGaO, znAlO, znMgO, znSnO, znLiO, inSnO, alZnO, znOCl or ZnOF, it is noted that, for doped metal oxides, the formulae provided only show the elemental composition and not the content of the individual elements, for example: znMgO is composed of three elements, zn, mg and O. The average particle diameter of the metal oxide may be, for example, 2nm to 15nm, and examples thereof are 2nm, 3nm, 4nm, 5nm, 6nm, 7nm, 8nm, 9nm, 10nm, 11nm, 12nm, 13nm, 14nm or 15nm. The thickness of the electron transport layer is, for example, 10nm to 100nm.
In some embodiments of the present application, the material of the electron injection layer is selected from at least one of an alkali metal halide including, but not limited to, liF, an alkali metal organic complex including, but not limited to, lithium 8-hydroxyquinoline, or an organic phosphine compound including, but not limited to, at least one of an organic phosphorus oxide, an organic thiophosphine compound, or an organic selenophosphine compound. The thickness of the electron injection layer is, for example, 10nm to 100nm.
In order to further enhance the photoelectric performance and the service life of the optoelectronic device, in some embodiments of the present application, as shown in fig. 4, the optoelectronic device 1 further includes a hole functional layer 15, where the hole functional layer 15 is disposed between the first quantum dot light emitting layer 131 and the anode 11, and the hole functional layer 15 includes a hole injection layer and/or a hole transport layer. For the hole functional layer 15 including a hole injection layer and a hole transport layer, the hole injection layer is closer to the anode 11 than the hole transport layer, and the hole transport layer is closer to the first quantum dot light emitting layer 131 than the hole injection layer. The thickness of the hole function layer 15 may be, for example, 10nm to 200nm.
The thickness of the hole injection layer is, for example, 10nm to 100nm, and the material of the hole injection layer is, for example, selected from the group consisting of poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonic acid), copper phthalocyanine, titanyl phthalocyanine, 4 '-tris (N-3-methylphenyl-N-phenylamino) triphenylamine, 4' -tris [ 2-naphthylphenylamino ] amine]Triphenylamine, 2,3At least one of 5, 6-tetrafluoro-7, 7', 8' -tetracyanodimethyl-p-benzoquinone, 2,3,6,7,10, 11-hexacyano-1, 4,5,8,9, 12-hexaazabenzophenanthrene, transition metal oxide or transition metal chalcogenide, wherein the transition metal oxide is selected from NiO x 、MoO x 、WO x 、CrO x Or CuO x At least one of the transition metal chalcogenide compounds is selected from MoS x 、MoSe x 、WS x 、WSe x Or CuS x At least one of them.
The thickness of the hole transport layer is, for example, 10nm to 100nm, and the material of the hole transport layer is, for example, selected from poly (9, 9-dioctylfluorene-CO-N- (4-butylphenyl) diphenylamine) (abbreviated as TFB, CAS number 220797-16-0), 3-hexyl-substituted polythiophene (CAS number 104934-50-1), poly (9-vinylcarbazole) (PVK, CAS number 25067-59-8), poly [ bis (4-phenyl) (4-butylphenyl) amine](Poly-TPD, CAS number 472960-35-3), poly (N, N ' -bis (4-butylphenyl) -N, N ' -diphenyl-1, 4-phenylenediamine-CO-9, 9-dioctylfluorene) (PFB, CAS number 223569-28-6), 4',4 "-tris (carbazol-9-yl) triphenylamine (TCTA, CAS number 139092-78-7), 4' -bis (9-carbazole) biphenyl (CBP, CAS number 58328-31-7), N ' -diphenyl-N, N ' -bis (3-methylphenyl) -1,1' -biphenyl-4, 4' -diamine (TPD, CAS number 65181-78-4), N ' - (1-naphthyl) -1,1' -biphenyl-4, 4' -diamine (NPB, CAS number 123847-85-8), poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonic acid), doped or undoped graphene, C60, niO, moO 3 、WO 3 、V 2 O 5 、CrO 3 At least one of CuO or P-type gallium nitride. The cation of the first material is selected from alkyl substituted pyridine ions, which can form an energy level gradient between the first quantum dot light emitting layer 131 and the hole transport layer, thereby reducing a hole injection barrier between the first quantum dot light emitting layer 131 and the hole transport layer, and can shorten a distance between the insulating quantum dot ligand and the hole transport material, thereby further improving a hole injection level of the photoelectric device.
The embodiment of the application also provides a preparation method of the photoelectric device, which can be used for preparing any one of the photoelectric devices in the embodiment of the application, as shown in fig. 5, and comprises the following steps:
s1, providing a prefabricated device comprising a bottom electrode;
s2, applying a first quantum dot solution to one side of the bottom electrode, wherein the first quantum dot solution comprises first quantum dots and a first material, the first material is ionic liquid, and then drying to obtain a first quantum dot luminescent layer;
and S3, forming a top electrode on one side of the first quantum dot light-emitting layer far away from the bottom electrode.
In the preparation method, the first quantum dot solution comprises the first quantum dots and the first material, and the first material is ionic liquid and is used for preparing the first quantum dot luminescent layer through a solution method. Based on the unique flowing property of the ionic liquid, in the film forming process of the first quantum dot luminous layer, the ionic liquid can dynamically fill the pores between the adjacent quantum dots, so that the porosity and the surface roughness of the first quantum dot luminous layer are effectively reduced, the surface flatness and the density of the first quantum dot luminous layer are improved, the leakage current of the prepared photoelectric device is effectively reduced, the risk of direct contact between two functional layers oppositely arranged on two sides of the first quantum dot luminous layer in the prepared photoelectric device is reduced, the phenomenon of quenching carrier luminescence is improved, and in addition, the ionic liquid also has the effect of passivating the surface defects of the first quantum dots, so that the photoelectric performance and the service life of the prepared photoelectric device are improved. It should be noted that the structural compositions of the bottom electrode and the top electrode are described with reference to the foregoing description regarding the anode and the cathode, and the constituent compositions of the first quantum dots and the first material are also described with reference to the foregoing description.
In some embodiments of the present application, the ionic liquid is used as a solvent of a first quantum dot solution, the solute of the quantum dot solution comprises first quantum dots, and the solvent of the quantum dot solution is a first material.
Wherein, the photoelectric device is of a positive structure, the bottom electrode is an anode, the top electrode is a cathode, and the preparation method of the photoelectric device further comprises the following steps between the step S2 and the step S3: s is S a Forming a second material on one side of the first quantum dot light-emitting layer away from the bottom electrode,the conductivity of the second material is lower than the conductivity of the first material; the second material is arranged between the first quantum dot light-emitting layer and the top electrode. The compositional composition of the second material is described with reference to the foregoing.
In some embodiments of the present application, step S a The method comprises the following steps: and applying a second material solution on one side of the first quantum dot light-emitting layer far away from the bottom electrode, and then drying to form a second material on one side of the first quantum dot light-emitting layer far away from the bottom electrode, wherein the second material at least covers part of one side of the first quantum dot light-emitting layer far away from the bottom electrode, and the temperature of the drying treatment is lower than the boiling point of the second material.
Further, in order to further promote carrier transport balance of the optoelectronic device, in some embodiments of the present application, at step S a In step S3, the method for manufacturing an optoelectronic device further includes the steps of: s is S b Forming a second quantum dot light emitting layer on a side of the first quantum dot light emitting layer away from the bottom electrode, the material of the second quantum dot light emitting layer including second quantum dots, the second quantum dots being described with reference to the foregoing; the second material is located between the first quantum dot light emitting layer and the second quantum dot light emitting layer. The method for forming the second quantum dot light emitting layer may be, for example, a solution method including the steps of: and applying a second quantum dot solution on one side of the first quantum dot light-emitting layer far away from the bottom electrode, and then drying to form the second quantum dot light-emitting layer. The solvent of the second quantum dot solution may be, for example, a second material including, but not limited to, at least one of n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, or n-undecane.
Or the photoelectric device is of an inverted structure, the bottom electrode is a cathode, the top electrode is an anode, and before the step S2, the preparation method of the photoelectric device further comprises the steps of: s is S a Forming a second material on one side of the bottom electrode, the second material having a conductivity lower than the first material; the second material is arranged between the first quantum dot light-emitting layer and the bottom electrode. The compositional composition of the second material is described with reference to the foregoing.
In some embodiments of the present application, step S a ' comprising the steps of: applying a first electrode on one side of the bottom electrodeAnd a second material solution, and then drying treatment is performed to form a second material on one side of the bottom electrode, wherein the second material covers at least part of one side of the bottom electrode, and the temperature of the drying treatment is lower than the boiling point of the second material.
Further, in order to further promote carrier transport balance of the optoelectronic device, in some embodiments of the present application, at step S a The method of fabricating the optoelectronic device further comprises the steps of: s is S b And forming a second quantum dot light-emitting layer on one side of the bottom electrode, wherein the second material is formed on one side of the second quantum dot light-emitting layer away from the bottom electrode. The method for forming the second quantum dot light emitting layer may be, for example, a solution method including the steps of: and applying a second quantum dot solution on one side of the bottom electrode, and then drying to form a second quantum dot luminescent layer. The solvent of the second quantum dot solution may be, for example, a second material including, but not limited to, at least one of n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, or n-undecane.
It can be appreciated that, since the conductivity of the second material is lower than the conductivity of the first material, for example, the difference between the conductivity of the first material and the conductivity of the second material is 0.2mS/cm to 0.8mS/cm, the electron injection rate of the optoelectronic device is slowed down while the hole injection level of the optoelectronic device is increased, so as to increase the matching degree of the hole injection level and the electron injection level, promote the electron-hole transport balance, and further increase the luminous efficiency and the service life of the optoelectronic device.
Specifically, the prefabricated device may further include other functional layers besides the bottom electrode, for example, for an optoelectronic device with a front-mounted structure, the prefabricated device may further include a substrate and a hole functional layer, the bottom electrode is disposed between the substrate and the hole functional layer, and correspondingly, the first quantum dot light emitting layer is formed on a side of the hole functional layer away from the bottom electrode; for example, for an inverted photoelectric device, the prefabricated device may further include a substrate and an electronic functional layer, the bottom electrode is disposed between the substrate and the electronic functional layer, and the first quantum dot light emitting layer is formed on a side of the electronic functional layer away from the bottom electrode. It should be noted that, in the present application, the description of "the a layer is formed on the side of the B layer" or "the a layer is formed on the side of the B layer away from the C layer" may mean that the a layer is directly formed on the side of the B layer or the side of the B layer away from the C layer, that is, the a layer is in direct contact with the B layer; it may also mean that the grounding between layers a is formed on one side of layer B or on one side of layer B away from layer C, i.e. other functional layers may also be formed between layers a and B.
In step S2, the first quantum dot solution is applied by at least one of spin coating, inkjet printing, knife coating, dip-coating, dipping, spray coating, roll coating, or casting.
In step S2, the "drying process" includes all processes capable of obtaining higher energy of the first quantum dot solution located at one side of the bottom electrode to be converted into a solid film, including but not limited to a heat treatment and/or a fire vacuum drying process, wherein the heat treatment includes but is not limited to a constant temperature heat treatment process or a non-constant temperature heat treatment (e.g., temperature gradient) process.
In order to avoid volatilization of the first material at room temperature, in some embodiments of the present application, the first material has a boiling point of 60 ℃ to 80 ℃ at 760mm hg.
In order to both enhance the surface smoothness and compactness of the first quantum dot light emitting layer 131 and ensure that the first quantum dot light emitting layer has a desirable energy level structure, in some embodiments of the present application, the concentration of the first quantum dot in the first quantum dot solution is 20mg/mL to 40mg/mL, for example, may be 20mg/mL to 25mg/mL, 25mg/mL to 30mg/mL, 30mg/mL to 35mg/mL, or 35mg/mL to 40mg/mL, and exemplified by 20mg/mL, 25mg/mL, 30mg/mL, 35mg/mL, or 40mg/mL.
As an example, the photoelectric device is of a positive structure, and the preparation method of the photoelectric device comprises the following steps:
s10, providing a prefabricated device, wherein the prefabricated device consists of a substrate and an anode which are arranged in a stacked manner, and a hole injection layer is formed on one side of the anode away from the substrate;
S20, forming a hole transport layer on one side of the hole injection layer away from the anode;
s30, applying a first quantum dot solution on one side of the hole transport layer far away from the hole injection layer, wherein a solvent of the first quantum dot solution is ionic liquid, a solute of the first quantum dot solution is first quantum dots, and drying to form a first quantum dot luminescent layer;
s40, applying a second material solution on one side of the first quantum dot light-emitting layer far away from the hole transport layer, and then drying to form a second material on one side of the first quantum dot light-emitting layer far away from the hole transport layer, wherein the second material at least covers part of one side of the first quantum dot light-emitting layer far away from the hole transport layer;
s50, applying a second quantum dot solution to one side of the first quantum dot light-emitting layer far away from the hole transport layer, wherein a solvent of the second quantum dot solution is a second material, a solute of the second quantum dot solution is a second quantum dot, and drying treatment is carried out to form a second quantum dot light-emitting layer, and the second material is positioned between the first quantum dot light-emitting layer and the second quantum dot light-emitting layer;
s60, forming an electron transmission layer on one side of the second quantum dot light-emitting layer far away from the first quantum dot light-emitting layer;
and S70, forming a cathode on one side of the electron transport layer far away from the second quantum dot light-emitting layer.
In the above preparation method, step S50 may be omitted.
As an example, the photoelectric device is of an inverted structure, and the preparation method of the photoelectric device includes the following steps:
s10', providing a prefabricated device, wherein the prefabricated device consists of a substrate and a cathode which are arranged in a stacked manner, and an electron transport layer is formed on one side of the cathode away from the substrate;
s20', applying a second quantum dot solution on one side of the electron transport layer far away from the cathode, wherein the solute of the second quantum dot solution is a second quantum dot, the solvent of the second quantum dot solution is a second material, and drying to form a second quantum dot luminescent layer;
s30', applying a second material solution on the side, far away from the electron transport layer, of the second quantum dot light-emitting layer, and then drying the second material solution to form a second material on the side, far away from the electron transport layer, of the second quantum dot light-emitting layer, wherein the second material at least covers part of the side, far away from the electron transport layer, of the second quantum dot light-emitting layer;
s40', applying a first quantum dot solution to the second quantum dot light-emitting layer far away from the electron transport layer, wherein a solvent of the first quantum dot solution is ionic liquid, a solute of the first quantum dot solution is the first quantum dot, and drying to obtain the first quantum dot light-emitting layer, and the second material is positioned between the second quantum dot light-emitting layer and the first quantum dot light-emitting layer;
S50', forming a hole transport layer on one side of the first quantum dot light-emitting layer far away from the second quantum dot light-emitting layer;
s60', forming a hole injection layer on one side of the hole transport layer far away from the first quantum dot light-emitting layer;
s70', an anode is formed on a side of the hole injection layer remote from the hole transport layer.
In the above preparation method, step S20 'or step S30' may be omitted.
It should be noted that, the preparation method of each film layer in the optoelectronic device includes, but is not limited to, a solution method and a deposition method, the solution method includes, but is not limited to, spin coating, ink-jet printing, knife coating, dip-coating, dipping, spray coating, roll coating or casting; the deposition method includes a chemical method including, but not limited to, a chemical vapor deposition method, a continuous ion layer adsorption and reaction method, an anodic oxidation method, an electrolytic deposition method, or a coprecipitation method, and a physical method including, but not limited to, a thermal evaporation plating method, an electron beam evaporation plating method, a magnetron sputtering method, a multi-arc ion plating method, a physical vapor deposition method, an atomic layer deposition method, or a pulsed laser deposition method. When the film layer is prepared by a solution method, a drying treatment process is added to convert the wet film into a dry film.
It will be appreciated that the method of manufacturing an optoelectronic device may also include other steps, such as: after each film layer of the photoelectric device is prepared, the photoelectric device needs to be packaged.
The embodiment of the application also provides electronic equipment, which comprises any one of the photoelectric devices in the embodiment of the application or any one of the photoelectric devices manufactured by the manufacturing method. The electronic device may be, for example, any electronic product with display function, including but not limited to, a smart phone, a tablet computer, a notebook computer, a digital camera, a digital video camera, a smart wearable device, a smart weighing electronic scale, a vehicle display, a television set, or an electronic book reader, where the smart wearable device may be, for example, a smart bracelet, a smart watch, a Virtual Reality (VR) helmet, or the like.
The technical solutions and technical effects of the present application are described in detail below by means of specific examples, comparative examples and experimental examples, and the following examples are only some examples of the present application and are not intended to limit the present application in any way.
Example 1
The embodiment provides a photoelectric device and a preparation method thereof, the photoelectric device is a quantum dot light emitting diode with a forward structure, as shown in fig. 6, in a bottom-up direction, the photoelectric device 1 includes a substrate 10, an anode 11, a hole function layer 15, a first quantum dot light emitting layer 131, an interface modification layer formed by a second material 132, a second quantum dot light emitting layer 133, an electron function layer 14 and a cathode 12, which are sequentially stacked, wherein the hole function layer 15 is composed of a hole injection layer 151 and a hole transport layer 152 which are stacked, the hole injection layer 151 is closer to the anode 11 than the hole transport layer 152, and the hole transport layer 152 is closer to the first quantum dot light emitting layer 131 than the hole injection layer 151; the electron functional layer 14 is an electron transport layer.
The materials and thicknesses of the respective layers in the optoelectronic device 1 are as follows:
the material of the substrate 10 is glass with the thickness of 0.5mm;
the anode 11 is made of ITO and has a thickness of 80nm;
the cathode 12 is made of Ag and has a thickness of 100nm;
the hole injection layer 151 is made of PEDOT PSS with the thickness of 20nm;
the hole transport layer 152 is made of TFB and has a thickness of 25nm;
the material of the first quantum dot luminescent layer 131 consists of first quantum dots and ionic liquid, wherein the first quantum dots are CdZnSe quantum dots, the luminescent color is blue, 0.05mmol of oleic acid ligand is connected to the surface of each 1mmol of CdZnSe quantum dots, the luminescent wavelength is 468nm and the peak width is 15nm, the ionic liquid is 1-butyl-4-methylpyridine chloride, and the thickness is 15nm;
the second material 132 is n-octane, and the thickness of an interface modification layer formed by the second material 132 is 5nm;
the material of the second quantum dot light emitting layer 133 includes second quantum dots, which are the same as the first quantum dots, and have a thickness of 15nm;
the material of the electronic function layer 14 is nano ZnO with the particle size distribution of 8nm to 15nm and the thickness of 30nm.
The preparation method of the photoelectric device in the embodiment comprises the following steps:
s1.1, providing a substrate, sputtering ITO on one side of the substrate to obtain an ITO layer, dipping a small amount of soapy water on the surface of the ITO layer by using a cotton swab to wipe the surface of the ITO layer so as to remove impurities visible to the naked eyes on the surface, sequentially ultrasonically cleaning the substrate comprising the ITO by using deionized water, acetone for 15min, ethanol for 15min and isopropanol for 15min, and performing ultraviolet-ozone surface treatment for 5min after drying to obtain the substrate comprising an anode;
S1.2, spin-coating PEDOT on one side of the anode far away from the substrate in the step S1.1 under the air environment of normal temperature and normal pressure: performing constant temperature heat treatment on the PSS aqueous solution at 150 ℃ for 30min to obtain a hole injection layer;
s1.3, spin-coating TFB-chlorobenzene solution on one side of the hole injection layer far away from the anode in the step S1.2 under the nitrogen environment of normal temperature and normal pressure, and then placing the film at a constant temperature of 150 ℃ for heat treatment for 30min to obtain a hole transport layer;
s1.4, spin-coating a first quantum dot solution on one side of the hole transport layer far away from the hole injection layer in the step S1.3 under a nitrogen environment at normal temperature and normal pressure, wherein the solvent of the first quantum dot solution is 1-butyl-4-methylpyridine chloride, the concentration of CdZnSe quantum dots in the first quantum dot solution is 30mg/mL, and then placing the first quantum dot solution at a constant temperature of 60 ℃ for heat treatment for 5min to obtain a first quantum dot luminescent layer;
s1.5, spin-coating n-octane on one side of the first quantum dot luminescent layer far away from the hole transport layer in the step S1.4 under the nitrogen environment of normal temperature and normal pressure, and then placing the substrate at the constant temperature of 80 ℃ for heat treatment for 5min to obtain an interface modification layer;
s1.6, spin-coating a second quantum dot solution on one side of an interface modification layer formed by the second material 132 in the step S1.5, which is far away from the first quantum dot luminescent layer, in a nitrogen environment at normal temperature and normal pressure, wherein the solvent of the second quantum dot solution is n-octane, and then performing constant temperature heat treatment at 80 ℃ for 5min to obtain a second quantum dot luminescent layer;
S1.7, spin-coating a nano ZnO-ethanol solution on one side of the second quantum dot luminescent layer far away from the interface modification layer formed by the second material 132 in the step S1.6 under a nitrogen environment at normal temperature and normal pressure, and then performing constant-temperature heat treatment for 30min at 80 ℃ to obtain an electronic functional layer;
s1.8 placing the prefabricated device comprising the electronic functional layer under an air pressure of 4×10 -6 And in an evaporation bin of mbar, ag is thermally evaporated on one side, far away from the light-emitting layer, of the electron transport layer in the step S1.7 through a mask plate to obtain a cathode, and then the cathode is packaged by ultraviolet curing glue to obtain the photoelectric device.
Example 2
The present embodiment provides an optoelectronic device and a method for manufacturing the same, and compared with the optoelectronic device in embodiment 1, the optoelectronic device in this embodiment is only different in that: the first quantum dots in the first quantum dot light-emitting layer are different in content.
Compared with the preparation method of the photoelectric device in example 1, the preparation method of this example only differs in that: the concentration "30mg/mL" of CdZnSe quantum dots in the first quantum dot solution in step S1.4 was replaced with "20mg/mL", and the volume of the first quantum dot solution spin-coated on the side of the hole transport layer remote from the hole injection layer in this example was the same as in example 1.
Example 3
The present embodiment provides an optoelectronic device and a method for manufacturing the same, and compared with the optoelectronic device in embodiment 1, the optoelectronic device in this embodiment is only different in that: the first quantum dots in the first quantum dot light-emitting layer are different in content.
Compared with the preparation method of the photoelectric device in example 1, the preparation method of this example only differs in that: the concentration "30mg/mL" of CdZnSe quantum dots in the first quantum dot solution in step S1.4 was replaced with "40mg/mL", and the volume of the first quantum dot solution spin-coated on the side of the hole transport layer remote from the hole injection layer in this example was the same as in example 1.
Example 4
The present embodiment provides an optoelectronic device and a method for manufacturing the same, and compared with the optoelectronic device in embodiment 1, the optoelectronic device in this embodiment is only different in that: the first quantum dots in the first quantum dot light-emitting layer are different in content.
Compared with the preparation method of the photoelectric device in example 1, the preparation method of this example only differs in that: the concentration "30mg/mL" of CdZnSe quantum dots in the first quantum dot solution in step S1.4 was replaced with "10mg/mL", and the volume of the first quantum dot solution spin-coated on the side of the hole transport layer remote from the hole injection layer in this example was the same as in example 1.
Example 5
The present embodiment provides an optoelectronic device and a method for manufacturing the same, and compared with the optoelectronic device in embodiment 1, the optoelectronic device in this embodiment is only different in that: the first quantum dots in the first quantum dot light-emitting layer are different in content.
Compared with the preparation method of the photoelectric device in example 1, the preparation method of this example only differs in that: the concentration "30mg/mL" of CdZnSe quantum dots in the first quantum dot solution in step S1.4 was replaced with "50mg/mL", and the volume of the first quantum dot solution spin-coated on the side of the hole transport layer remote from the hole injection layer in this example was the same as in example 1.
Example 6
The present embodiment provides an optoelectronic device and a method for manufacturing the same, and compared with the optoelectronic device of embodiment 1, the optoelectronic device of the present embodiment is only different in that: the ionic liquid in the first quantum dot luminescent layer is replaced by 1-butyl-4-methylpyridine tetrafluoroborate from 1-butyl-4-methylpyridine chloride.
Compared with the preparation method of the photoelectric device in example 1, the preparation method of this example only differs in that: the "solvent of the first quantum dot solution is 1-butyl-4-methylpyridine chloride salt" in step S1.4 is replaced by "solvent of the first quantum dot solution is 1-butyl-4-methylpyridine tetrafluoroborate salt".
Example 7
The present embodiment provides an optoelectronic device and a method for manufacturing the same, and compared with the optoelectronic device of embodiment 1, the optoelectronic device of the present embodiment is only different in that: the ionic liquid in the first quantum dot luminescent layer is replaced by 1-hexyl-4-methylpyridine chloride salt from 1-butyl-4-methylpyridine chloride salt.
Compared with the preparation method of the photoelectric device in example 1, the preparation method of this example only differs in that: the "solvent of the first quantum dot solution is 1-butyl-4-methylpyridine chloride salt" in step S1.4 is replaced by "solvent of the first quantum dot solution is 1-hexyl-4-methylpyridine chloride salt".
Example 8
The present embodiment provides an optoelectronic device and a method for manufacturing the same, and compared with the optoelectronic device of embodiment 1, the optoelectronic device of the present embodiment is only different in that: and replacing the ionic liquid in the first quantum dot luminescent layer by 1-ethyl-3-methylimidazole chloride from 1-butyl-4-methylpyridine chloride.
Compared with the preparation method of the photoelectric device in example 1, the preparation method of this example only differs in that: the "solvent of the first quantum dot solution is 1-butyl-4-methylpyridine chloride salt" in step S1.4 is replaced by "solvent of the first quantum dot solution is 1-ethyl-3-methylimidazole chloride salt".
Example 9
The present embodiment provides an optoelectronic device and a method for manufacturing the same, and compared with the optoelectronic device of embodiment 1, the optoelectronic device of the present embodiment is only different in that: the second quantum dot light emitting layer is omitted.
Compared with the preparation method of the photoelectric device in example 1, the preparation method of this example only differs in that: omitting the step S1.6, replacing the step S1.7 with 'spin-coating a nano ZnO-ethanol solution on one side of the second material 132 film layer far away from the first quantum dot luminescent layer under the nitrogen environment of normal temperature and normal pressure', and then placing the film layer at the constant temperature of 80 ℃ for heat treatment for 30min to obtain an electronic functional layer.
Example 10
The present embodiment provides an optoelectronic device and a method for manufacturing the same, and compared with the optoelectronic device of embodiment 1, the optoelectronic device of the present embodiment is only different in that: the ionic liquid in the first quantum dot luminescent layer is replaced by 1-ethyl-3-methyl quaternary ammonium chloride salt from 1-butyl-4-methyl pyridine chloride salt.
Compared with the preparation method of the photoelectric device in example 1, the preparation method of this example only differs in that: the "solvent of the first quantum dot solution is 1-butyl-4-methylpyridine chloride salt" in step S1.4 is replaced by "solvent of the first quantum dot solution is 1-ethyl-3-methyl quaternary ammonium chloride salt".
Example 11
The present embodiment provides an optoelectronic device and a method for manufacturing the same, and compared with the optoelectronic device of embodiment 1, the optoelectronic device of the present embodiment is only different in that: and replacing the ionic liquid in the first quantum dot luminescent layer by 1-ethyl-3-methyl quaternary phosphonium chloride from 1-butyl-4-methyl pyridine chloride.
Compared with the preparation method of the photoelectric device in example 1, the preparation method of this example only differs in that: the "solvent of the first quantum dot solution is 1-butyl-4-methylpyridine chloride salt" in step S1.4 is replaced by "solvent of the first quantum dot solution is 1-ethyl-3-methyl quaternary phosphorus chloride salt".
Example 12
The present embodiment provides an optoelectronic device and a method for manufacturing the same, and compared with the optoelectronic device in embodiment 1, the optoelectronic device in this embodiment is only different in that: the second material is distributed on one side of the first quantum dot light-emitting layer far away from the hole transport layer in an island shape.
Compared with the preparation method of the photoelectric device in example 1, the preparation method of this example only differs in that: and replacing the step S1.5 with taking an equal volume of mixed solution of n-pentane and n-octane, spin-coating the mixed solution on the first quantum dot luminescent layer, heating for ten minutes at forty degrees, and forming a porous island structure only containing n-octane after the n-pentane volatilizes.
Comparative example 1
The present comparative example provides an optoelectronic device and a method of manufacturing the same, which differs from the optoelectronic device of example 1 only in that: the second quantum dot light-emitting layer and the second material film layer are omitted, the material of the first quantum dot light-emitting layer is first quantum dots, and the thickness of the first quantum dot light-emitting layer is 25nm.
The production method of this comparative example differs from that of example 1 only in that: the step S1.4 is replaced by 'spin-coating a first quantum dot-n-octane solution on one side of the hole transport layer far away from the hole injection layer in the step S1.3 under the nitrogen environment of normal temperature and normal pressure, wherein the concentration of the first quantum dot in the first quantum dot-n-octane solution is 30mg/mL, then placing the solution in the constant temperature heat treatment at 80 ℃ for 5min to obtain a light-emitting layer', and omitting the step S1.5 and the step S1.6.
Comparative example 2
The present comparative example provides an optoelectronic device and a method for manufacturing the same, which differs from the optoelectronic device of example 1 only in that: the second quantum dot light emitting layer and the second material film layer are omitted.
Compared with the preparation method of the photoelectric device in example 1, the preparation method of this example only differs in that: step S1.5 and step S1.6 are omitted.
Experimental example
The performance of the optoelectronic devices of examples 1 to 12 and comparative examples 1 and 2 was tested by using a frieda FPD optical characteristic measuring device (including a marine optical USB2000, a LabView controlled QE-PRO spectrometer, a Keithley2400, a high-precision digital source table Keithley 6485, an optical fiber with an inner diameter of 50 μm, a device test probe and fixture, and an efficiency test system built by various connecting wires and data cards, an efficiency test cassette, a data acquisition system, and other elements), to obtain parameters such as a turn-on voltage, a current, a brightness, a luminescence spectrum, and the like of each optoelectronic device, and then calculating to obtain key parameters such as an external quantum efficiency, a power efficiency, and the like, and testing the service lives of the above-mentioned individual optoelectronic devices by using a life test device.
The service life testing method comprises the following steps: under the drive of constant current (2 mA), carrying out electroluminescence service life analysis on each photoelectric device by adopting a 128-path QLED service life testing system, recording the time (T95, h) required by each photoelectric device for reducing the maximum brightness to 95 percent, and calculating the time (T95@1000nit, h) required by each photoelectric device for reducing the brightness from 100 percent to 95 percent under the brightness of 1000nit by a reduction fitting formula.
In the preparation process of each photoelectric device, after the first quantum dot light-emitting layer is prepared, a bruck atomic force microscope is adopted to detect the surface average roughness (Ra, nm) of the first quantum dot light-emitting layer according to the GB/T31227-2014 standard.
The performance test data for each optoelectronic device is detailed in table 1 below:
table 1 list of performance test data for optoelectronic devices of examples 1-12 and comparative examples
As can be seen from table 1, the overall performance of the optoelectronic devices in examples 1 to 12 has significant advantages compared with the optoelectronic devices in the comparative examples, and is specifically shown as follows: the first quantum dot light-emitting layer of the optoelectronic devices of examples 1-12 had higher surface flatness, EQE, than the optoelectronic device of comparative example max Higher and longer service life. Taking the photovoltaic device of example 7 as an example, the Ra of the photovoltaic device of example 7 is only 58% of the Ra of the photovoltaic device of the comparative example, and the EQE of the photovoltaic device of example 7 max Is EQE in comparative example max And the T95 of the photovoltaic device in example 7 is 1.5 times the T95 of the photovoltaic device in the comparative example, and the T95@1000nit of the photovoltaic device in example 7 is 1.4 times the T95@1000nit of the photovoltaic device in the comparative example. The following is explained: the ionic liquid is added into the first quantum dot luminous layer, so that the surface of the first quantum dot luminous layer can be improved The surface flatness and the compactness, and the side of the first quantum dot luminescent layer, which is close to the cathode, is provided with a second material, so that electron injection is slowed down while hole injection level is improved, electron-hole transmission balance is promoted, and the luminous efficiency and the service life of the photoelectric device are improved.
As can be seen from the performance test data of the photovoltaic devices in example 1 and example 9, the overall performance of the photovoltaic device in example 1 is better than that of the photovoltaic device in example 9, thereby demonstrating that: compared with the method that only the interface modification layer formed by the second material is additionally arranged in the photoelectric device, the method that the interface modification layer formed by the second material and the second quantum dot luminescent layer are additionally arranged in the photoelectric device can further promote electron-hole transmission balance of the photoelectric device, so that the comprehensive performance of the photoelectric device is further improved, and the reason is probably that: the interface modification layer formed by the second material can reduce the contact area between the electronic functional layer and the first material, so that electron injection is slowed down, and the direct contact between the electronic functional layer and the first material can be further avoided by adding the second quantum dot luminescent layer.
As can be seen from the performance test data of example 1, comparative example 1 and comparative example 2 and fig. 7, the overall performance of the photovoltaic device of comparative example 2 is better than that of comparative example 1, because: the ionic liquid is doped in the first quantum dot luminescent layer, so that the surface evenness and density of the first quantum dot luminescent layer can be improved, and the carrier transmission capacity is improved, so that the comprehensive performance of the photoelectric device is improved. The overall performance of the photovoltaic device of example 1 is superior to that of comparative example 2 because: the interface modification layer and the second quantum dot luminescent layer formed by the second material are additionally arranged in the photoelectric device, so that electron injection can be slowed down while hole injection level is improved, electron-hole transmission balance of the photoelectric device is promoted, and comprehensive performance of the photoelectric device is further improved.
From the performance test data of examples 1 to 5, the overall performance of the photovoltaic devices in examples 4 and 5 was inferior to that of examples 1 to 3, and it was found that: in the formation process of the first quantum dot light-emitting layer, the concentration of the first quantum dot in the first quantum dot solution is 20mg/mL to 40mg/mL, so that the comprehensive performance of the photoelectric device can be further improved, and the reason may be that: the first quantum dot and the ionic liquid are compounded in a proper proportion, so that the surface evenness and compactness of the first quantum dot luminescent layer can be improved, and the first quantum dot luminescent layer is ensured to have an ideal energy level structure.
As is clear from the performance test data of examples 1, 6 to 8, 10 and 11, the overall performance of the photovoltaic devices in examples 8, 10 and 11 is inferior to that in examples 1, 6 and 7, and this is explained by: the cation of the ionic liquid in the first quantum dot light-emitting layer is selected from alkyl substituted pyridine ions, so that the comprehensive performance of the photoelectric device can be further improved, and the reason is probably that: the cation of the ionic liquid is selected from alkyl substituted pyridine ions, so that an energy level gradient can be formed between the first quantum dot light-emitting layer and the hole transport layer, a hole injection potential barrier between the first quantum dot light-emitting layer and the hole transport layer is reduced, and the distance between the insulated quantum dot ligand and the hole transport material can be shortened, so that the hole injection level of the photoelectric device is further improved.
The above describes in detail an optoelectronic device, a method for manufacturing the optoelectronic device, and an electronic device provided in the embodiments of the present application. The principles and embodiments of the present application are described herein with reference to specific examples, the description of which is only for aiding in understanding the technical solution of the present application and its core ideas; those of ordinary skill in the art will appreciate that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the scope of the corresponding technical solutions of the embodiments of the present application.

Claims (19)

1. An optoelectronic device, comprising:
an anode;
a cathode disposed opposite the anode; and
the first quantum dot light-emitting layer is arranged between the anode and the cathode;
the material of the first quantum dot light-emitting layer comprises first quantum dots and first materials, and a second material is arranged on one side, close to the cathode, of the first quantum dot light-emitting layer;
the first material is an ionic liquid, and the second material has a conductivity lower than that of the first material.
2. The optoelectronic device of claim 1, wherein the material of the first quantum dot light emitting layer consists of the first quantum dot and the first material.
3. The optoelectronic device of claim 1, wherein an interface modification layer is disposed between the first quantum dot light emitting layer and the cathode, the second material forming the interface modification layer.
4. A photovoltaic device according to claim 3, wherein the interface modification layer has a thickness of 3nm to 6nm.
5. The optoelectronic device of claim 1, wherein in the first quantum dot light emitting layer, the first quantum dot: the mass ratio of the first material is 1: (20-40);
and/or the thickness of the first quantum dot light-emitting layer is 10nm to 15nm;
and/or the difference between the conductivity of the first material and the conductivity of the second material is 0.2mS/cm to 0.8mS/cm.
6. The optoelectronic device of claim 1, wherein the cation of the first material is selected from the group consisting of alkyl quaternary ammonium ions, alkyl quaternary phosphonium ions, alkyl substituted imidazole ions, and alkyl substituted pyridine ions;
and/or the anions of the first material are selected from at least one of halogen ions or acid ions.
7. The optoelectronic device of claim 6, wherein the alkyl quaternary ammonium ion is selected from one of an N, N-diethyl-N-methyl-N- (N-propyl) ammonium cation or an N, N-diethyl-N-methyl- (2-methoxyethyl) ammonium cation;
and/or the alkyl quaternary phosphonium ion is selected from one of tetradecyl tributyl phosphonium cation, tetrahydroxymethyl phosphonium cation, ethyl tributyl phosphonium cation or tetrabutyl phosphonium cation;
and/or the alkyl-substituted imidazole ion is selected from one of 1-butyl-3-methylimidazole cation, 1-ethyl-3-methylimidazole cation, 1-octyl-3-methylimidazole cation, 1-decyl-3-methylimidazole cation, 1-hexyl-3-methylimidazole cation or 1-methyl-3-n-octylimidazole cation;
and/or the alkyl-substituted pyridine ion is selected from at least one of 1-butyl-4-methylpyridine ion, 1-hexyl-4-methylpyridine ion, N-ethylpyridine ion, N-butylpyridine ion, N-hexylpyridine ion, N-octylpyridine ion, or N-methyl-N-propylpyridine ion;
and/or the halogen ion is selected from F - 、Cl - 、Br - Or I - At least one of (a) and (b);
and/or the acid radical ion is selected from BF 4 - 、PF 6 - 、CF 3 SO 3- 、CF 3 COO - 、(CF 3 SO 2 ) 3 C - 、(C 2 F 5 SO 2 ) 3 C - 、(CF 3 SO 2 ) 2 N - 、C 3 F 7 COO - 、C 4 F 9 SO 3 - 、(C 2 F 5 SO 2 ) 2 N - 、SbF 6 - 、AsF 6 - 、CB 11 H 12 - 、NO 2 - 、NO 3 - 、ClO 4 - Or C 8 H 17 SO 4 - At least one of them.
8. An optoelectronic device according to claim 7, wherein the first material is selected from the group consisting of 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazolium hexafluoro-borate, 1-ethyl-3-methylimidazolium bistrifluoro-methylsulfonyliminate, 1-octyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazole chloride, 1-decyl-3-methylimidazolium hexafluorophosphate, 1-ethyl-3-methylimidazole bis (pentafluoroethylsulfonyl) imide, 1-hexyl-3-methylimidazolium tetrafluoroborate, 1-methyl-3-N-octylimidazole tetrafluoroborate, 1-ethyl-3-methylimidazole dicyandiamide, N-diethyl-N-methyl-N- (N-propyl) trifluoromethyl trifluoroammonium borate, 1-butyl-3-methylimidazolium triflate, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium bistrifluoro-imide and N-ethyl-2-methoxyethyl-N- (2-methoxyethyl) ammonium bistrifluoro-imide, and quaternary ammonium salts of 1-ethyl-3-methylimidazole, at least one of 1-hexyl-4-methylpyridine chloride, 1-hexyl-4-methylpyridine bromide, 1-butyl-4-methylpyridine tetrafluoroborate or 1-butyl-4-methylpyridine hexafluorophosphate.
9. The optoelectronic device of claim 1, further comprising an electronic functional layer disposed between the cathode and the first quantum dot light emitting layer; the electron functional layer comprises an electron transport layer and/or an electron injection layer, and for the electron functional layer comprising the electron transport layer and the electron injection layer, the electron transport layer is closer to the first quantum dot light emitting layer than the electron injection layer, and the electron injection layer is closer to the cathode than the electron transport layer;
wherein the material of the electron transport layer comprises metal oxide selected from ZnO and TiO 2 、SnO 2 、BaO、Ta 2 O 3 、ZrO 2 、TiLiO、ZnGaO、ZnAlO、ZnMgO、ZnSnO、ZnLiO、InSnO、AlZnO, znOCl, znOF or ZnMgLiO;
and/or the material of the electron injection layer includes at least one of an alkali metal halide, an alkali metal organic complex, or an organic phosphine compound selected from at least one of an organic phosphorus oxide, an organic thiophosphine compound, or an organic selenophosphine compound.
10. The optoelectronic device of claim 1, further comprising a hole-functional layer disposed between the first quantum dot light-emitting layer and the anode, the hole-functional layer comprising a hole-injection layer and/or a hole-transport layer, the hole-injection layer being closer to the anode than the hole-transport layer and the hole-transport layer being closer to the first quantum dot light-emitting layer than the hole-injection layer for the hole-functional layer comprising the hole-injection layer and the hole-transport layer;
The hole injection layer is made of poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonic acid), copper phthalocyanine, titanyl phthalocyanine, 4 '-tris (N-3-methylphenyl-N-phenylamino) triphenylamine, 4' -tris [ 2-naphthylphenylamino ] amine]At least one of triphenylamine, 2,3,5, 6-tetrafluoro-7, 7', 8' -tetracyanodimethyl-p-benzoquinone, 2,3,6,7,10, 11-hexacyano-1, 4,5,8,9, 12-hexaazabenzophenanthrene, transition metal oxide or transition metal chalcogenide, the transition metal oxide being selected from Ni O x 、MoO x 、WO x 、CrO x Or CuO x At least one of the transition metal chalcogenide compounds is selected from MoS x 、MoSe x 、WS x 、WSe x Or CuS x At least one of (a) and (b);
and/or the material of the hole transport layer is selected from poly (9, 9-dioctylfluorene-CO-N- (4-butylphenyl) diphenylamine), 3-hexyl substituted polythiophene, poly (9-vinylcarbazole), poly [ bis (4-phenyl) (4-butylphenyl) amine]Poly (N, N '-bis (4-butylphenyl) -N, N' -diphenyl-1, 4-phenylenediamine-CO-9, 9-dioctylfluorene), 4 '-tris (carbazol-9-yl) triphenylamine, 4' -bis (9-carbazol) biphenyl, N '-diphenyl-N, N' -bis (3-methyl)Phenyl) -1,1 '-biphenyl-4, 4' -diamine, N '-diphenyl-N, N' - (1-naphthyl) -1,1 '-biphenyl-4, 4' -diamine, poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonic acid), doped or undoped graphene, C60, niO, moO3, WO 3 、V 2 O 5 、CrO 3 At least one of CuO or P-type gallium nitride.
11. The optoelectronic device according to any one of claims 1 to 10, further comprising: the second quantum dot light-emitting layer is arranged on one side, close to the cathode, of the first quantum dot light-emitting layer;
the material of the second quantum dot light-emitting layer comprises second quantum dots, and the second material is arranged between the first quantum dot light-emitting layer and the second quantum dot light-emitting layer;
for the photoelectric device with the electron function layer arranged between the cathode and the first quantum dot light-emitting layer, the second quantum dot light-emitting layer is arranged between the first quantum dot light-emitting layer and the electron function layer.
12. The optoelectronic device of claim 11, wherein the second material is a solvent that disperses the first quantum dots and/or the second quantum dots;
and/or the thickness of the second quantum dot light-emitting layer is 10nm to 15nm;
and/or the luminous colors of the first quantum dots and the second quantum dots are the same.
13. The optoelectronic device of claim 12, wherein the second material is selected from at least one of n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, or n-undecane;
And/or the first quantum dot and the second quantum dot are the same.
14. The optoelectronic device of claim 11, wherein the first quantum dot or the second quantum dot are independently selected from at least one of a single component quantum dot, a core-shell structure quantum dot, an inorganic perovskite quantum dot, or an organic-inorganic hybrid perovskite quantum dot;
the material of the single component quantum dot, the material of the core-shell structure quantum dot and the material of the shell of the core-shell structure quantum dot are selected from at least one of II-VI compound, III-V compound, IV-VI compound or I-III-VI compound independently of each other, wherein the II-VI compound is selected from at least one 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 or HgZnSTe, the III-V 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, alNP, alNAs, alNSb, alPAs, alPSb, inNP, inNAs, inNSb, inPAs, inPSb, gaAlNP, gaAlNAs, gaAlNSb, gaAlPAs, gaAlPSb, gaInNP, gaInNAs, gaInNSb, gaInPAs, gaInPSb, inAlNP, inAlNAs, inAlNSb, inAlPAs or InAlPSb, the IV-VI 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 or SnPbSTe, the I-III-VI compound is selected from CuInS 2 、CuInSe 2 Or AgInS 2 At least one of (a) and (b);
and/or the materials of the anode and the cathode are selected from at least one of metal, carbon material or metal oxide independently of each other, the metal is selected from at least one of Al, ag, cu, mo, au, ba, ca or Mg, the carbon material is selected from at least one of graphite, carbon nanotube, graphene or carbon fiber, and the metal oxide is selected from at least one of indium tin oxide, fluorine doped tin oxide, tin antimony oxide, aluminum doped zinc oxide, gallium doped zinc oxide, indium doped zinc oxide or magnesium doped zinc oxide.
15. A method of fabricating an optoelectronic device comprising the steps of:
providing a prefabricated device comprising a bottom electrode;
applying a first quantum dot solution on one side of the bottom electrode, wherein the first quantum dot solution comprises first quantum dots and a first material, the first material is ionic liquid, and then drying to obtain a first quantum dot luminescent layer; and
forming a top electrode on one side of the first quantum dot light-emitting layer away from the bottom electrode;
the preparation method comprises the steps of forming a first quantum dot luminescent layer on one side of a substrate, forming a bottom electrode on the side of the substrate, forming a bottom electrode on the bottom electrode, forming a top electrode on the side of the first quantum dot luminescent layer, and forming a bottom electrode on the side of the substrate, wherein the photoelectric device is of a positive structure, the bottom electrode is an anode, the top electrode is a cathode, and the preparation method further comprises the steps of: forming a second material on one side of the first quantum dot light-emitting layer away from the bottom electrode, wherein the conductivity of the second material is lower than that of the first material; the second material is arranged between the first quantum dot light-emitting layer and the top electrode;
Or the photoelectric device is of an inverted structure, the bottom electrode is a cathode, the top electrode is an anode, and before the step of applying the first quantum dot solution on one side of the bottom electrode, the preparation method further comprises the steps of: forming a second material on one side of the bottom electrode, the second material having a conductivity lower than a conductivity of the first material; the second material is disposed between the first quantum dot light emitting layer and the bottom electrode.
16. The method of claim 15, wherein the optoelectronic device is a front-mounted structure, and the forming the second material on the side of the first quantum dot light-emitting layer away from the bottom electrode comprises: applying a second material solution on one side of the first quantum dot light-emitting layer far away from the bottom electrode, and then drying to form a second material on one side of the first quantum dot light-emitting layer far away from the bottom electrode, wherein the second material at least covers part of one side of the first quantum dot light-emitting layer far away from the bottom electrode, and the temperature of the drying treatment is lower than the boiling point of the second material;
alternatively, the optoelectronic device is an inverted structure, and the step of forming the second material on one side of the bottom electrode includes: a second material solution is applied to one side of the bottom electrode, and then a drying process is performed to form the second material on one side of the bottom electrode, wherein the second material covers at least a portion of one side of the bottom electrode, and wherein the drying process is performed at a temperature lower than the boiling point of the second material.
17. The method of manufacturing according to claim 15, wherein the optoelectronic device is a front-mounted structure, the method further comprising the step of, after the step of forming the second material on a side of the first quantum dot light emitting layer remote from the bottom electrode, and before the step of forming the top electrode: forming a second quantum dot light-emitting layer on one side of the first quantum dot light-emitting layer far away from the bottom electrode, wherein the material of the second quantum dot light-emitting layer comprises second quantum dots; the second material is positioned between the first quantum dot light-emitting layer and the second quantum dot light-emitting layer;
alternatively, the optoelectronic device is in an inverted structure, and before the step of forming the second material on one side of the bottom electrode, the preparation method further includes the steps of: and forming a second quantum dot light-emitting layer on one side of the bottom electrode, wherein the second material is formed on one side of the second quantum dot light-emitting layer away from the bottom electrode.
18. The method of any one of claims 15 to 17, wherein the cation of the ionic liquid is selected from alkyl quaternary ammonium ions, alkyl quaternary phosphonium ions, alkyl substituted imidazole ions, or alkyl substituted pyridine ions;
And/or the anions of the ionic liquid are selected from at least one of halogen ions or acid radical ions;
and/or the ionic liquid has a boiling point of 60 ℃ to 80 ℃ at 760mm hg;
and/or the concentration of the first quantum dots in the first quantum dot solution is 20mg/mL to 40mg/mL;
and/or the difference between the conductivity of the first material and the conductivity of the second material is 0.2mS/cm to 0.8mS/cm;
and/or the second material is selected from at least one of n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane or n-undecane.
19. An electronic device comprising an electro-optical device as claimed in any one of claims 1 to 14 or comprising an electro-optical device manufactured by a manufacturing method as claimed in any one of claims 15 to 18.
CN202211028104.4A 2022-08-25 2022-08-25 Photoelectric device, preparation method of photoelectric device and electronic equipment Pending CN117693213A (en)

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