Hybrid light emitting device, display panel, and display apparatus

Abstract

This application provides a hybrid light-emitting device, a display panel, and a display apparatus. The hybrid light-emitting device includes a substrate, a first electrode layer, a first light-emitting unit, a charge-generating layer, a second light-emitting unit, and a second electrode layer stacked together. The first light-emitting unit includes at least one first light-emitting layer, and the second light-emitting unit includes a second light-emitting layer. Under the action of a driving voltage, the first light-emitting layer emits light of a first color. A portion of the first color light passes through the charge-generating layer and enters the second light-emitting layer, exciting the second light-emitting layer to generate light of a second color, thereby causing the hybrid light-emitting device to emit light of a target color. Therefore, the hybrid light-emitting device achieves hybrid excitation and emission by using the first light-emitting unit and the second light-emitting unit in series and in combination, utilizing the electroluminescence of the first light-emitting layer and the photoluminescence of the second light-emitting layer, thus improving the overall luminous efficiency, lifespan, and operational stability of the hybrid light-emitting device.

Description

Technical Field

[0001] This application relates to the field of display technology, and more particularly to a hybrid light-emitting device, a display panel having the hybrid light-emitting device, and a display device having the display panel. Background Technology

[0002] Organic light-emitting diodes (OLEDs) offer advantages such as self-illumination, wide color gamut, thinness, fast response time, wide viewing angle, and high brightness. Quantum dot light-emitting diodes (QLEDs) offer advantages such as high color purity, high quantum efficiency, and easily tunable color. Both are emerging light-emitting technologies in recent years. OLED technology has been widely applied in display technologies such as smartphones, televisions, automotive displays, and wearable devices, with small-size display panels showing a trend towards mass production.

[0003] While OLED technology has significantly improved in stability, some organic light-emitting materials used in OLEDs currently suffer from rapid degradation and relatively short lifespans, resulting in poor stability of OLED display panels, especially in medium and large-sized display panels, which increases manufacturing costs. Although QLED technology can solve the problem of short lifespan, quantum dot electroluminescence exhibits a positive correlation between current density and luminous efficiency at the required brightness, making it difficult to achieve the luminous efficiency of OLEDs at low current densities, leading to higher power consumption.

[0004] Therefore, how to solve the problems of short lifespan and high power consumption of OLED devices at low current densities is an urgent issue for those skilled in the art. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this application is to provide a hybrid light-emitting device, a display panel having the hybrid light-emitting device, and a display device having the display panel. It aims to solve the problems of short lifespan of OLED devices and high power consumption of OLED devices at low current density in the related art. By using photoluminescence combined with electroluminescence to achieve hybrid excitation light emission, the overall luminous efficiency and lifespan of the hybrid light-emitting device can be improved at the same time, thereby improving the display effect and user experience of the display panel and display device, and has broad application prospects.

[0006] To address the aforementioned technical problems, this application provides a hybrid light-emitting device, comprising a substrate, a first electrode layer, and a second electrode layer. The hybrid light-emitting device further includes a first light-emitting unit, a charge-generating layer, and a second light-emitting unit. The first electrode layer, the first light-emitting unit, the charge-generating layer, the second light-emitting unit, and the second electrode layer are stacked on the substrate along the light-emitting direction. The first light-emitting unit includes at least one first light-emitting layer, and the second light-emitting unit includes a second light-emitting layer. Under the action of a driving voltage, the first light-emitting layer emits light of a first color. A portion of the first color light passes through the charge-generating layer and enters the second light-emitting layer, exciting the second light-emitting layer to generate light of a second color, thereby causing the hybrid light-emitting device to emit light of a target color.

[0007] In summary, the hybrid light-emitting device provided in this application includes a substrate, a first electrode layer, a first light-emitting unit, a charge-generating layer, a second light-emitting unit, and a second electrode layer. The first electrode layer, the first light-emitting unit, the charge-generating layer, the second light-emitting unit, and the second electrode layer are stacked on the substrate along the light emission direction. The first light-emitting unit includes at least one first light-emitting layer, and the second light-emitting unit includes a second light-emitting layer. Under the action of a driving voltage, the first light-emitting layer emits a first color light. Part of the first color light passes through the charge-generating layer and enters the second light-emitting layer, exciting the second light-emitting layer to generate a second color light, thereby enabling the hybrid light-emitting device to emit a target color light. Therefore, the hybrid light-emitting device of this application achieves hybrid excitation and emission by using the first light-emitting unit and the second light-emitting unit in series, utilizing the electroluminescence of the first light-emitting layer and the photoluminescence of the second light-emitting layer. This improves the overall luminous efficiency, lifespan, and operational stability of the hybrid light-emitting device, fundamentally solving the problems of short lifespan of OLED devices and low luminous efficiency caused by high power consumption at low current densities.

[0008] In an exemplary embodiment, the first light-emitting unit further includes a hole injection layer, a first hole transport layer, and a first electron transport layer. The hole injection layer is disposed on the side of the first electrode layer facing the first light-emitting layer. The first hole transport layer is disposed between the hole injection layer and the first light-emitting layer. The first electron transport layer is located between the first light-emitting layer and the charge generation layer. The second light-emitting unit further includes an electron injection layer, a second electron transport layer, and a second hole transport layer. The electron injection layer is disposed on the side of the second electrode layer facing the second light-emitting layer. The second electron transport layer is located between the electron injection layer and the second light-emitting layer. The second hole transport layer is located between the second light-emitting layer and the charge generation layer.

[0009] In an exemplary embodiment, the charge generation layer is disposed between the first light-emitting unit and the second light-emitting unit. The charge generation layer includes a first sub-charge generation layer and a second sub-charge generation layer stacked together. The first sub-charge generation layer is disposed on the side of the first electron transport layer of the first light-emitting unit that faces away from the first electrode layer. The second sub-charge generation layer is disposed on the side of the second hole transport layer of the second light-emitting unit that faces away from the second electrode layer. The first sub-charge generation layer is used to generate electrons and inject electrons into the first light-emitting layer. The second sub-charge generation layer is used to generate holes and inject holes into the second light-emitting layer.

[0010] In an exemplary embodiment, the first sub-charge generation layer is an N-type charge generation layer, the second sub-charge generation layer is a P-type charge generation layer, and both the first and second sub-charge generation layers contain metal nanowires.

[0011] In an exemplary embodiment, the hybrid light-emitting device further includes an optical adjustment layer disposed on the side of the second electrode layer opposite to the second light-emitting unit, and the optical adjustment layer is used to optically modulate the hybrid light-emitting device.

[0012] In an exemplary embodiment, the first light-emitting layer comprises at least two blue dopants and has at least two discrete emission peaks; the second light-emitting layer comprises yellow quantum dots of one particle size and has one absorption peak; the first color light may be blue light, the second color light may be yellow light, and the target color light may be white light; or, the first light-emitting layer comprises at least two dopants of any color among red, green, and blue and has at least two discrete emission peaks; the second light-emitting layer comprises quantum dots of at least one particle size of the same color as the first light-emitting layer and has at least one absorption peak; or, the first light-emitting layer comprises at least two dopants of any color among red, green, and blue and has at least two discrete emission peaks; the second light-emitting layer comprises quantum dots of at least two particle sizes of the same color as the first light-emitting layer and has at least two discrete absorption peaks; wherein at least one emission peak of the first light-emitting layer is located between the absorption peaks of the second light-emitting layer.

[0013] In an exemplary embodiment, the first light-emitting unit further includes a first energy level adjustment layer and a first hole blocking layer. The first energy level adjustment layer is disposed between the first light-emitting layer and the first hole transport layer, and the first hole blocking layer is disposed between the first light-emitting layer and the first electron transport layer. The first energy level adjustment layer is used to adjust the energy level matching of the first light-emitting layer and adjust the ability of charge carriers to be injected into the first light-emitting layer from the first hole transport layer. The first hole blocking layer is used to prevent holes from passing through the first light-emitting layer and entering the first electron transport layer. The second light-emitting unit includes a second energy level adjustment layer and a second hole blocking layer. The second energy level adjustment layer is disposed between the second light-emitting layer and the second hole transport layer, and the second hole blocking layer is disposed between the second light-emitting layer and the second electron transport layer. The second energy level adjustment layer is used to adjust the energy level matching of the second light-emitting layer and adjust the ability of charge carriers to be injected into the second light-emitting layer from the second hole transport layer. The second hole blocking layer is used to prevent holes from passing through the second light-emitting layer and entering the second electron transport layer.

[0014] In an exemplary embodiment, the HOMO energy levels of the first hole transport layer, the first energy level adjustment layer, and the first light-emitting layer are arranged in a sequentially increasing gradient. The HOMO energy level difference between the first hole transport layer and the first energy level adjustment layer is less than 0.3 eV, and the HOMO energy level difference between the first energy level adjustment layer and the first light-emitting layer is less than 0.3 eV. Similarly, the HOMO energy levels of the second hole transport layer, the second energy level adjustment layer, and the second light-emitting layer are arranged in a sequentially increasing gradient. The HOMO energy level difference between the second hole transport layer and the second energy level adjustment layer is less than 0.3 eV, and the HOMO energy level difference between the second energy level adjustment layer and the second light-emitting layer is less than 0.3 eV. The LUMO energy level difference between the first hole blocking layer and the first light-emitting layer is less than 0.2 eV, and the T1 energy level between the first hole blocking layer and the first light-emitting layer is greater than or equal to 2.5 eV and less than or equal to 3.3 eV; the LUMO energy level difference between the second hole blocking layer and the second light-emitting layer is less than 0.2 eV, and the T1 energy level between the second hole blocking layer and the second light-emitting layer is greater than or equal to 2.5 eV and less than or equal to 3.3 eV.

[0015] Based on the same inventive concept, this application also provides a display panel, which includes the above-mentioned hybrid light-emitting device.

[0016] Based on the same inventive concept, this application also provides a display device, which includes a housing and the aforementioned display panel, wherein the display panel is disposed within the housing.

[0017] In summary, the display panel and display device provided in this application include a housing and a display panel, with the display panel disposed on the housing. The display panel includes a hybrid light-emitting device, which comprises a substrate, a first electrode layer, a first light-emitting unit, a charge-generating layer, a second light-emitting unit, and a second electrode layer. The first electrode layer, the first light-emitting unit, the charge-generating layer, the second light-emitting unit, and the second electrode layer are stacked on the substrate along the light-emitting direction. The first light-emitting unit includes at least one first light-emitting layer, and the second light-emitting unit includes a second light-emitting layer. Under the action of a driving voltage, the first light-emitting layer emits a first color light. A portion of the first color light passes through the charge-generating layer and enters the second light-emitting layer, exciting the second light-emitting layer to generate a second color light, thereby causing the hybrid light-emitting device to emit a target color light. Therefore, the hybrid light-emitting device of this application uses the first light-emitting unit and the second light-emitting unit in series, and achieves hybrid excitation and light emission by utilizing the electroluminescence of the first light-emitting layer and the photoluminescence of the second light-emitting layer. This improves the overall luminous efficiency, lifespan, and operational stability of the hybrid light-emitting device, fundamentally solving the problems of short lifespan of OLED devices and low luminous efficiency caused by high power consumption at low current densities. This, in turn, improves the display effect and user experience of the display panel and display device. Moreover, the hybrid light-emitting device has a simple overall structure, advantages in mass production and cost, and broad application prospects. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the first layer structure of the hybrid light-emitting device disclosed in the first embodiment of this application.

[0020] Figure 2 for Figure 1 The diagram shows the layer structure of the first light-emitting unit.

[0021] Figure 3 for Figure 1 The diagram shows the layer structure of the second light-emitting unit.

[0022] Figure 4 for Figure 1 The diagram shows the specific layer structure of the hybrid light-emitting device.

[0023] Figure 5This is a schematic diagram of the second layer structure of the hybrid light-emitting device disclosed in the first embodiment of this application.

[0024] Figure 6 This is a partial top view of the display panel disclosed in the second embodiment of this application.

[0025] Figure 7 This is a schematic diagram of the structure of the display device disclosed in the third embodiment of this application.

[0026] Explanation of reference numerals in the attached figures: 1-Display device; 10-Housing; 30-Display panel; 001-First direction; 002-Second direction; A1-Sub-pixel area; A2-Non-sub-pixel area; 100-Hybrid light-emitting device; 110-Substrate; 120-First electrode layer; 130-First light-emitting unit; 140-Charge generation layer; 150-Second light-emitting unit; 160-Second electrode layer; 131-First light-emitting layer; 132-Hole injection layer; 133-First hole transport layer; 134-First electron transport layer; 151-Second light-emitting layer; 152-Electron injection layer; 153-Second electron transport layer; 154-Second hole transport layer; 170-Optical adjustment layer; 141-First sub-charge generation layer; 143-Second sub-charge generation layer; 135-First energy level adjustment layer; 136-First hole blocking layer; 155-Second energy level adjustment layer; 156-Second hole blocking layer. Detailed Implementation

[0027] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the disclosure of this application.

[0028] The following descriptions of the embodiments are based on the accompanying illustrations and are used to illustrate specific embodiments in which this application can be implemented. The component designations used herein, such as "first," "second," etc., are merely for distinguishing the described objects and have no sequential or technical meaning. Unless otherwise specified, the terms "connection" and "linkage" used in this application include both direct and indirect connections (linkages). Directional terms used in this application, such as "up," "down," "front," "back," "left," "right," "inner," "outer," "side," etc., are merely for reference to the accompanying illustrations. Therefore, the use of directional terms is for better and clearer explanation and understanding of this application, and does not indicate or imply that the referred device or element must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on this application.

[0029] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joint" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two elements. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances. It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. Furthermore, the terms "comprising," "may include," "include," or "may include" used in this application indicate the presence of the corresponding disclosed function, operation, element, etc., and do not limit one or more other functions, operations, elements, etc. Moreover, the terms "comprising" or "include" indicate the presence of the corresponding features, number, steps, operations, elements, components, or combinations thereof disclosed in the specification, but do not exclude the presence or addition of one or more other features, number, steps, operations, elements, components, or combinations thereof, and are intended to cover non-exclusive inclusion. It is also important to understand that “at least one” as described in this article means one or more, such as one, two or three, while “multiple” means at least two, such as two or three, unless otherwise explicitly specified.

[0030] In the embodiments of this application, "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship. The terms "parallel," "perpendicular," etc., are specific to the current technological level, not absolutely strict mathematical definitions, and slight deviations are allowed; approximations of parallelism or perpendicularity are acceptable. For example, A and B being parallel means that A and B are parallel or approximately parallel, and the angle between A and B can be between 0 and 5 degrees. As another example, A and B being perpendicular means that A and B are perpendicular or approximately perpendicular, and the angle between A and B can be between 85 and 95 degrees.

[0031] In the exemplary embodiments disclosed herein, "the orthographic projection of B lies within the range of the orthographic projection of A" or "the orthographic projection of A includes the orthographic projection of B" means that the boundary of the orthographic projection of B falls within the boundary range of the orthographic projection of A, or the boundary of the orthographic projection of A overlaps with the boundary of the orthographic projection of B. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of this application.

[0032] Organic light-emitting diodes (OLEDs) and quantum dot light-emitting diodes (QLEDs) are emerging light-emitting technologies that offer advantages over traditional liquid crystal displays (LCDs), such as higher contrast, faster response times, and wider color gamut. OLED technology has been widely applied in display technologies such as smartphones, televisions, automotive displays, and wearable devices, with small-size display panels showing a trend towards mass production. While OLED technology has significantly improved stability, some organic light-emitting materials used in OLEDs currently suffer from rapid degradation and relatively short lifespans, resulting in poor stability of OLED display panels, particularly increasing manufacturing costs in medium and large-size display panels. Although QLED technology can address the short lifespan issue, the positive correlation between current density and luminous efficiency in quantum dot electroluminescence at desired brightness makes it difficult to achieve the luminous efficiency of OLEDs at low current densities, leading to higher power consumption. To address the aforementioned technical problems, this application provides a hybrid light-emitting device, a display panel having the hybrid light-emitting device, and a display device having the display panel. It aims to solve the problems of short lifespan and high power consumption of OLED devices at low current densities in related technologies. By combining photoluminescence with electroluminescence to achieve hybrid excitation and light emission, the overall luminous efficiency and lifespan of the hybrid light-emitting device can be improved simultaneously.

[0033] Please see Figure 1 , Figure 1This is a schematic diagram of the first layer structure of the hybrid light-emitting device disclosed in the first embodiment of this application. In this embodiment, the hybrid light-emitting device 100 may include a substrate 110, a first electrode layer 120, a first light-emitting unit 130, a charge generation layer (CGL) 140, a second light-emitting unit 150, and a second electrode layer 160, wherein the substrate 110, the first electrode layer 120, the first light-emitting unit 130, the charge generation layer 140, the second light-emitting unit 150, and the second electrode layer 160 are sequentially stacked along the light emission direction. That is, the first electrode layer 120 is disposed on one side of the substrate 110, the first light-emitting unit 130 is disposed on the side of the first electrode layer 120 opposite to the substrate 110, the charge-generating layer 140 is disposed on the side of the first light-emitting unit 130 opposite to the first electrode layer 120, the second light-emitting unit 150 is disposed on the side of the charge-generating layer 140 opposite to the first light-emitting unit 130, and the second electrode layer 160 is disposed on the side of the second light-emitting unit 150 opposite to the charge-generating layer 140. In other words, the charge-generating layer 140 is located between the first light-emitting unit 130 and the second light-emitting unit 150. The light-emitting direction can be from the first electrode layer 120 to the second electrode layer 160.

[0034] Please refer to the following: Figure 1 , Figure 2 and Figure 3 , Figure 2 for Figure 1 The schematic diagram of the layer structure of the first light-emitting unit 130 shown is as follows. Figure 3 for Figure 1 The diagram shows the layer structure of the second light-emitting unit 150. In this embodiment, the first light-emitting unit 130 may include at least one first light-emitting layer 131, and the second light-emitting unit 150 may include a second light-emitting layer 151. The first light-emitting layer 131 emits a first color light under the action of a driving voltage. Part of the first color light passes through the charge generation layer 140 and is incident on the second light-emitting layer 151, exciting the second light-emitting layer 151 to generate a second color light, so that the hybrid light-emitting device 100 emits a target color light.

[0035] In this embodiment, the first light-emitting unit 130 can be an organic light-emitting unit, and the first light-emitting layer 131 can be an organic light-emitting layer. The second light-emitting unit 150 can be a quantum dot light-emitting unit, and the second light-emitting layer 151 can be a quantum dot light-emitting layer. Therefore, under the action of an applied driving voltage, the first light-emitting layer 131 directly emits the first color light through electroluminescence. Part of the first color light passes through the charge generation layer 140 along the emission direction and is incident on the second light-emitting layer 151, exciting the second light-emitting layer 151 to generate the second color light, that is, photoluminescence causes the second light-emitting layer 151 to generate the second color light. The first color light and the second color light complementarily mix to generate the target color light, and then the hybrid light-emitting device 100 emits the target color light along the emission direction.

[0036] It is understood that the second light-emitting layer 151 can also emit part of the second color light under the action of the driving voltage to increase the intensity of the second color light, thereby further enhancing the brightness of the target color light and supplementing the spectrum.

[0037] In this embodiment, the first color light can be blue light, the second color light can be yellow light, and the target color light can be white light. That is, the first color light and the second color light are complementary and mixed to form white light. Understandably, the blue light has high energy, which can efficiently excite the second light-emitting layer 151 to produce yellow light, improving the light conversion efficiency and reducing energy loss. Photoluminescence is used to assist in improving luminous efficiency and spectral saturation (i.e., improving color gamut coverage).

[0038] In this embodiment, the substrate 110 may be conductive glass with indium tin oxide (ITO) spin-coated on it, serving as a physical support platform for the construction of the hybrid light-emitting device 100, and supporting the functional film layer disposed thereon.

[0039] In this embodiment, the first electrode layer 120 can be an anode, and it can be made of transparent conductive materials such as indium tin oxide, indium zinc oxide (IZO), silver nanowires, metal mesh, or conductive polymers. The first electrode layer 120 can be used as a hole injection electrode and also performs conductive functions.

[0040] Please see Figure 2In this embodiment, the first light-emitting unit 130 may further include a hole injection layer (HIL) 132, which is disposed on the side of the first electrode layer 120 facing the first light-emitting layer 131. In this embodiment, the material of the hole injection layer 132 may include, but is not limited to, hole injection materials for organic light-emitting diodes such as copper phthalocyanine (CuPc), poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS), nickel oxide, molybdenum trioxide, and tungsten oxide. For example, molybdenum trioxide is used as the target material for the hole injection layer 132, which has significant functional advantages. Its high work function can effectively improve the energy level matching between the anode and the organic layer, thereby reducing the hole injection barrier and simultaneously acting as an electron blocker, which is beneficial for improving hole injection efficiency and carrier recombination probability. Moreover, the interfacial contact characteristics of molybdenum trioxide can form an ohmic-like contact interface with the charge generation layer 140, which can effectively distribute the charge flow direction of different periods in the AC field and suppress interface trap recombination.

[0041] In this embodiment, the first light-emitting unit 130 may further include a first hole transport layer (HTL) 133, which is disposed on the side of the hole injection layer 132 opposite to the first electrode layer 120, i.e., the first hole transport layer 133 is located between the hole injection layer 132 and the first light-emitting layer 131. The first hole transport layer 133 is used to transport holes to the first light-emitting layer 131, while blocking electrons from transporting from the first light-emitting layer 131 to the first electrode layer 120, so as to ensure electron recombination in the first light-emitting layer 131. The hole injection layer 132 is used to reduce the energy level difference and hole injection barrier between the first electrode layer 120 and the first hole transport layer 133, improve hole injection efficiency, improve interface contact, and alleviate interface charge accumulation. The material of the first hole transport layer 133 may include, but is not limited to: BPD Hole transport materials such as TAD and its derivatives can be used to deposit (e.g., by evaporation, coating, or inkjet printing) the hole transport layer material onto the hole injection layer 132, thus forming the first hole transport layer 133 on the hole injection layer 132. Understandably, the material of the first hole transport layer 133 can also be poly(N-vinylcarbazole) (PVK), One or more of these, but this application does not specifically limit them.

[0042] In this embodiment, the first light-emitting layer 131 may be an organic light-emitting layer, which provides light-emitting materials to achieve the light emission of the hybrid light-emitting device 100. In this embodiment, the material of the first light-emitting layer 131 may be one or more of PFO (poly(9,9-dioctylfluorene), F8BT (9,9-di-n-octylfluorene-benzothiadiazole copolymer), MEH-PPV (poly(2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene), or P-PPV (poly(p-phenylenevinylene)). It can be understood that in this embodiment, the first light-emitting layer 131 may be a red organic light-emitting layer, a green organic light-emitting layer, or a blue organic light-emitting layer, respectively used to emit red, green, or blue light. In other embodiments, the first light-emitting layer 131 may include a red organic light-emitting layer, a green organic light-emitting layer, and a blue organic light-emitting layer.

[0043] Please refer to the following: Figure 2 and Figure 4 , Figure 4 for Figure 1 The diagram shows a detailed layer structure of the hybrid light-emitting device 100. In this embodiment, the first light-emitting unit 130 may further include a first electron transport layer (ETL) 134. The first electron transport layer 134 is disposed on the side of the first light-emitting layer 131 opposite to the first hole transport layer 133. That is, the first light-emitting layer 131 is located between the first hole transport layer 133 and the first electron transport layer 134, and the first electron transport layer 134 is located between the first light-emitting layer 131 and the charge generation layer 140. The first electron transport layer 134 is used to transport electrons from the charge generation layer 140 to the first light-emitting layer 131, while blocking holes from being transported from the first light-emitting layer 131 to the charge generation layer 140, so as to ensure that holes recombine in the first light-emitting layer 131. In this embodiment, the material of the first electron transport layer 134 may include, but is not limited to: oxazole derivatives such as PBD (2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole) and BND (2,5-di(1-naphthyl)-1,3,4-diazole), metal chelates such as aluminum tris(8-hydroxyquinoline) (Alq3), and metal oxides such as zinc oxide (ZnO) and barium oxide (BaO). Specifically, the first electron transport layer 134 can be prepared on the first light-emitting layer 131 by depositing the material of the first electron transport layer (e.g., by evaporation, coating, or inkjet printing) onto the first light-emitting layer 131.

[0044] like Figure 1As shown in the embodiments of this application, the second electrode layer 160 can be a cathode, which can be made of a low work function metal or its alloy, such as a thin layer of silver (Ag), silver-magnesium alloy (MgAg), aluminum, etc. The second electrode layer 160 can be used as an electron injection electrode and also has a conductive function.

[0045] Please see Figure 3 and Figure 4 In this embodiment, the second light-emitting unit 150 may further include an electron injection layer (EIL) 152, which is disposed on the side of the second electrode layer 160 facing the second light-emitting layer 151. In this embodiment, the material of the electron injection layer 152 may include, but is not limited to, electron injection materials such as alkali metals, alkali metal fluorides, and alkali metal compounds, for example, NaF.

[0046] In this embodiment, the second light-emitting unit 150 may further include a second electron transport layer (ETL) 153, which is disposed on the side of the electron injection layer 152 opposite to the second electrode layer 160, i.e., the second electron transport layer 153 is located between the electron injection layer 152 and the second light-emitting layer 151. The second electron transport layer 153 is used to transport electrons to the second light-emitting layer 151, while blocking holes from being transported from the second light-emitting layer 151 to the second electrode layer 160. The electron injection layer 152 is used to reduce the energy level difference and electron injection barrier between the second electrode layer 160 and the second electron transport layer 153, thereby improving the electron injection capability. In this embodiment, the material of the second electron transport layer 153 may include, but is not limited to: oxazole derivatives such as PBD and BND, metal chelates such as aluminum tris(8-hydroxyquinoline) (Alq3), and metal oxides such as ZnO and BaO. Specifically, the second electron transport layer 153 can be prepared on the second light-emitting layer 151 by depositing the material of the second electron transport layer (e.g., by evaporation, coating, or inkjet printing) onto the second light-emitting layer 151.

[0047] In this embodiment, the second light-emitting layer 151 may be a quantum dot light-emitting layer, which is used to provide light-emitting materials to realize the light emission of the hybrid light-emitting device 100. In this embodiment, the material of the second light-emitting layer 151 may be one or more of group II-VI compounds, group III-V compounds, group II-V compounds, group III-VI compounds, group IV-VI compounds, group I-III-VI compounds, group II-IV-VI compounds, or group IV elements.

[0048] Specifically, the semiconductor materials used in the second light-emitting layer 151 include, but are not limited to, nanocrystals of II-VI semiconductors, such as CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, HgS, HgSe, HgTe, PbS, PbSe, PbTe, and other binary, ternary, and quaternary II-VI compounds; nanocrystals of III-V semiconductors, such as GaP, GaAs, InP, InAs, and other binary, ternary, and quaternary III-V compounds; and the semiconductor materials used for electroluminescence are not limited to II-V compounds, III-VI compounds, IV-VI compounds, I-III-VI compounds, II-IV-VI compounds, and group IV elements.

[0049] Understandably, in the embodiments of this application, the second light-emitting layer 151 can be a red quantum dot light-emitting layer, a green quantum dot light-emitting layer, or a blue quantum dot light-emitting layer, which generates a second color light of the corresponding color under the excitation of the first color light. In other embodiments, the second light-emitting layer 151 may include a red quantum dot light-emitting layer, a green quantum dot light-emitting layer, and a blue quantum dot light-emitting layer.

[0050] Please refer to the following: Figure 3 and Figure 4 In this embodiment, the second light-emitting unit 150 may further include a second hole transport layer (HTL) 154. The second hole transport layer 154 is disposed on the side of the second light-emitting layer 151 opposite to the second electron transport layer 153, that is, the second light-emitting layer 151 is located between the second electron transport layer 153 and the second hole transport layer 154, and the second hole transport layer 154 is located between the second light-emitting layer 151 and the charge generation layer 140. The second hole transport layer 154 is used to transport holes from the charge generation layer 140 to the second light-emitting layer 151, while blocking electrons from being transported from the second light-emitting layer 151 to the charge generation layer 140. In this embodiment, the material of the second hole transport layer 154 may include, but is not limited to, hole transport materials such as TPD, BPD, NPB, TAD and their derivatives. The hole transport layer material can be deposited (e.g., by evaporation, coating, inkjet printing) onto the second light-emitting layer 151 to prepare the second hole transport layer 154. Understandably, the material of the second hole transport layer 154 may also be one or more of PVK, CBP, and TCTA, and this application does not specifically limit it.

[0051] In this embodiment, the boundary of the orthographic projection of the first light-emitting unit 130 onto the substrate 110 overlaps with the boundary of the orthographic projection of the second light-emitting unit 150 onto the substrate 110. Specifically, in the direction perpendicular to the charge generation layer 140, the red quantum dot light-emitting layer is correspondingly disposed with the red organic light-emitting layer, the blue quantum dot light-emitting layer is correspondingly disposed with the blue organic light-emitting layer, and the green quantum dot light-emitting layer is correspondingly disposed with the green organic light-emitting layer. Here, "correspondingly disposed" means that, in the direction perpendicular to the charge generation layer 140, the boundary of the orthographic projection of the red quantum dot light-emitting layer onto the substrate 110 overlaps with the boundary of the orthographic projection of the red organic light-emitting layer onto the substrate 110; similarly, in the direction perpendicular to the charge generation layer 140, the boundary of the orthographic projection of the blue quantum dot light-emitting layer onto the substrate 110 overlaps with the boundary of the orthographic projection of the blue organic light-emitting layer onto the substrate 110, and the boundary of the orthographic projection of the green quantum dot light-emitting layer onto the substrate 110 overlaps with the boundary of the orthographic projection of the green organic light-emitting layer onto the substrate 110. Therefore, by superimposing organic light-emitting units of the same color on the quantum dot light-emitting layer, the advantages of both quantum dot light-emitting diodes and organic light-emitting diodes can be combined, thereby improving the luminous efficiency, lifespan, and stability of the hybrid light-emitting device 100.

[0052] like Figure 1 As shown in the embodiment of this application, the hybrid light-emitting device 100 may further include an optical adjustment layer 170. The optical adjustment layer 170 is disposed on the side of the second electrode layer 160 opposite to the electron injection layer 152 of the second light-emitting unit 150, that is, the optical adjustment layer 170 is located in the light-emitting direction of the hybrid light-emitting device 100. The optical adjustment layer 170 is used to optically modulate the hybrid light-emitting device 100 to optimize the light extraction efficiency and color purity of the hybrid light-emitting device 100 and suppress visual angle drift. The optical adjustment layer 170 can also be used to isolate water vapor and oxygen from contacting the second electrode layer 160 to prevent oxidation of the second electrode layer 160, thereby improving the service life of the hybrid light-emitting device 100.

[0053] like Figure 1 and Figure 4As shown in this embodiment, the charge generation layer 140 is disposed between the first light-emitting unit 130 and the second light-emitting unit 150. It can serve as an intermediate connecting layer to connect the first light-emitting unit 130 and the second light-emitting unit 150, thereby enabling the first light-emitting unit 130 and the second light-emitting unit 150 to work together. The charge generation layer 140 can be used to separate and generate electrons and holes under the action of an electric field, and inject electrons and holes into the first light-emitting layer 131 and the second light-emitting layer 151 respectively. That is, the charge generation layer 140 provides the charge carriers required for the first light-emitting layer 131 and the second light-emitting layer 151 to emit light, which determines the operating voltage, luminous efficiency and lifespan of the hybrid light-emitting device 100.

[0054] In this embodiment, the charge generation layer 140 may include a first sub-charge generation layer 141 and a second sub-charge generation layer 143 stacked together. The first sub-charge generation layer 141 is disposed on the side of the first electron transport layer 134 of the first light-emitting unit 130 opposite to the first electrode layer 120, i.e., the first sub-charge generation layer 141 is connected to the first electron transport layer 134 of the first light-emitting unit 130. The second sub-charge generation layer 143 is disposed on the side of the first sub-charge generation layer 141 opposite to the first electron transport layer 134, and the second sub-charge generation layer 143 is disposed on the side of the second hole transport layer 154 of the second light-emitting unit 150 opposite to the second electrode layer 160, i.e., the second sub-charge generation layer 143 is connected to the second hole transport layer 154 of the second light-emitting unit 150. The first sub-charge generation layer 141 may be an electron-rich doped layer, which is used to separate and generate electrons under the action of an electric field and inject electrons into the first light-emitting layer 131. The second sub-charge generation layer 143 may be a hole-rich doped layer, which is used to separate and generate holes under the action of an electric field and inject the holes into the second light-emitting layer 151.

[0055] In this embodiment, the first sub-charge generation layer 141 can be an N-type charge generation layer, and the second sub-charge generation layer 143 can be a P-type charge generation layer. That is, the charge generation layer 140 is formed by superimposing a P-type charge generation layer and an N-type charge generation layer. The P-type charge generation layer is a P-type hole transport material or a P-type doped hole transport material, and the material of the P-type charge generation layer is one of neutral PEDOT, MoOx, WOx, C60, or HATCN. The N-type charge generation layer is an N-type electron transport material or an N-type doped electron transport material, and the material of the N-type charge generation layer is one of ZnO, TiO, or BPhen:Cs2CO3.

[0056] In this embodiment, both the first sub-charge generation layer 141 and the second sub-charge generation layer 143 may contain metal nanowires. The special nanostructure of the metal nanowires can be stacked together to form a conductive network structure, thereby increasing the conductivity of the first sub-charge generation layer 141 and the second sub-charge generation layer 143, reducing the energy level barrier between the first light-emitting unit 130 and the charge generation layer 140, and between the charge generation layer 140 and the second light-emitting unit 150, and also reducing the driving voltage and power consumption, making the injection of electrons and holes more balanced, and further improving the light-emitting performance of the hybrid light-emitting device 100.

[0057] In the embodiments of this application, the metal nanowires may be at least one of Au nanowires, Ag nanowires, and Cu nanowires.

[0058] Therefore, the hybrid light-emitting device 100 of this application can be a series-connected stacked light-emitting device, in which the first light-emitting unit 130 and the second light-emitting unit 150 are connected in series through the charge generating layer 140, which can achieve higher brightness while reducing the current density of each light-emitting unit, thereby extending the service life of the hybrid light-emitting device 100. Moreover, the hybrid light-emitting device 100 combines the flexibility of OLED with the high color purity and high stability of OLED, thus achieving a wider color gamut, higher luminous efficiency, and longer service life.

[0059] In this embodiment, the first luminescent layer 131 may include at least two blue dopants (BD) and has at least two discrete emission peaks. The second luminescent layer 151 may include yellow quantum dots of a single particle size and have one absorption peak.

[0060] Specifically, the first emitting layer 131 incorporates two or more blue light dopants into its matrix. Different blue light dopants have different energy level structures, and after electro-excitation by an applied electric field, two or more discrete blue light emission peaks can be formed. For example, co-doping two different blue light dopants, DSA-Ph and v-DABNA, into a wide bandgap matrix can form two stable blue light emission peaks at approximately 450 nm and 480 nm, respectively. The relative intensity of the two emission peaks can be adjusted by controlling the doping ratio. The second emitting layer 151 contains yellow quantum dots of a certain particle size, thus forming a corresponding absorption peak. It can be understood that the same first emitting layer 131 can simultaneously output two or more short-wavelength blue light photons of different energies, with the photon energy covering a continuous blue light range, providing a multi-band excitation source for subsequent excitation of the second emitting layer 151. The absorption peak position of the quantum dots is determined by the quantum confinement effect; the smaller the particle size and the wider the bandgap, the more blue-shifted the absorption peak; the larger the particle size, the more red-shifted the absorption peak.

[0061] In one specific embodiment of this application, the first light-emitting layer 131 is doped with two blue light dopants, which, upon electroexcitation by an applied electric field, form two discrete blue light emission peaks (emission peaks) at 390 nanometers (nm) and 460 nanometers, respectively. The second light-emitting layer 151 contains yellow quantum dots of a single particle size, corresponding to an absorption peak at 390 nm and an emission peak at 545 nm. Therefore, under the action of an applied driving voltage, the first light emitted by the first light-emitting layer 131 through direct electroluminescence is blue light. Part of the blue light passes through the charge generation layer 140 along the emission direction and is incident on the second light-emitting layer 151, exciting the second light-emitting layer 151 to generate a second color light, which is yellow light. The blue light and the yellow light complementarily mix to form white light. Thus, the target color light emitted by the hybrid light-emitting device 100 along the emission direction is white light. Therefore, the current efficiency (cd / A) of the hybrid light-emitting device 100 of this application is about 12.5, which is about 25% higher than the current efficiency (about 10) of existing light-emitting devices, and the operating lifetime (1000 nit T95) of the hybrid light-emitting device 100 is about 118, which is about 18% higher than the operating lifetime (about 100) of existing light-emitting devices.

[0062] In this embodiment, the first light-emitting layer 131 may include at least two dopants of any one of red, green, and blue, and has at least two discrete emission peaks. The second light-emitting layer 151 may include quantum dots of at least one particle size of the same color as the first light-emitting layer 131, and has at least one absorption peak. The blue shift distance between the emission peak of the first light-emitting layer 131 and the absorption peak of the second light-emitting layer 151 may be 1-100 nanometers, and the first color light, the second color light, and the target color light may be light of the same color.

[0063] Understandably, the blue shift distance of the emission peak of the first luminescent layer 131 relative to the absorption peak of the second luminescent layer 151 is preferably 10-60 nanometers.

[0064] In one specific embodiment of this application, the first light-emitting layer 131 is doped with two green dopants, which, upon electroexcitation by an applied electric field, form two discrete green emission peaks at 470 nm and 530 nm, respectively. The second light-emitting layer 151 contains green quantum dots of a single particle size, corresponding to an absorption peak at 470 nm and an emission peak at 525 nm. Therefore, under the action of an applied driving voltage, the first light-emitting layer 131 directly emits green light through electroluminescence. Part of the green light passes through the charge generation layer 140 along the emission direction and enters the second light-emitting layer 151, exciting the second light-emitting layer 151 to generate green light. Thus, the target color light emitted by the hybrid light-emitting device 100 along the emission direction is green light. Therefore, the current efficiency (cd / A) of the hybrid light-emitting device 100 of this application is approximately 145, which is about 27% higher than the current efficiency of existing light-emitting devices (approximately 114). The operating lifetime (1000 nits T95) of the hybrid light-emitting device 100 is approximately 4700 cycles, which is about 42% higher than the operating lifetime of existing light-emitting devices (approximately 3300 cycles). The first light-emitting layer 131 and the second light-emitting layer 151 emit light of the same color without relying on complementary color mixing.

[0065] In this embodiment, the blue shift distance between the emission peak of the first emitting layer 131 and the absorption peak of the second emitting layer 151 can be 1-100 nanometers, for example, 1 nanometer, 5 nanometers, 10 nanometers, 15 nanometers, 20 nanometers, 25 nanometers, 30 nanometers, 32 nanometers, 35 nanometers, 40 nanometers, 45 nanometers, 48 ​​nanometers, 50 nanometers, 55 nanometers, 60 nanometers, 66 nanometers, 70 nanometers, 75 nanometers, 80 nanometers, 88 nanometers, 90 nanometers, 95 nanometers, 100 nanometers, or other values. This application does not impose specific limitations on this. Therefore, the green light emitted by the first emitting layer 131 can effectively excite green quantum dots of the same color system, realizing the hybrid excitation function of electroluminescence combined with photoluminescence, improving the brightness and current efficiency of monochromatic pixels, and meeting the high brightness requirement of monochromatic light of the hybrid light-emitting device 100. Moreover, the light emitted by the first light-emitting layer 131 illuminates the high absorption efficiency range of the quantum dots in the second light-emitting layer 151, which can avoid self-absorption loss caused by peak overlap, ensure energy transfer efficiency, and prevent color shift of the light from the first light-emitting layer 131, so that the R / G / B light of the hybrid light-emitting device 100 is emitted in monochromatic form, thus meeting the requirements of color purity and luminous efficiency of the hybrid light-emitting device 100.

[0066] In this embodiment, the first luminescent layer 131 may include at least two dopants of any color selected from red, green, and blue, and has at least two discrete emission peaks. The second luminescent layer 151 may include quantum dots of at least two particle sizes of the same color as the first luminescent layer 131, and has at least two discrete absorption peaks. At least one emission peak of the first luminescent layer 131 is located between the absorption peaks of the second luminescent layer 151, and the blue shift distance of the emission peak of the first luminescent layer 131 relative to the absorption peak of the second luminescent layer 151 may be 1-100 nanometers.

[0067] Understandably, the blue shift distance of the emission peak of the first luminescent layer 131 relative to the absorption peak of the second luminescent layer 151 is preferably 10-60 nanometers.

[0068] In one specific embodiment of this application, the first light-emitting layer 131 is doped with two green dopants, which, upon electroexcitation by an applied electric field, form two discrete green emission peaks (emission peaks) at 470 nm and 530 nm, respectively. The second light-emitting layer 151 contains green quantum dots of two different particle sizes. One particle size corresponds to an absorption peak at 470 nm and an emission peak at 525 nm, while the other particle size corresponds to an absorption peak at 490 nm and an emission peak at 545 nm. Therefore, under the action of an applied driving voltage, the first light-emitting layer 131 directly emits green light through electroluminescence. Part of the green light passes through the charge generation layer 140 along the emission direction and enters the second light-emitting layer 151, exciting the second light-emitting layer 151 to generate green light. Thus, the target color light emitted by the hybrid light-emitting device 100 along the emission direction is green light. Therefore, the current efficiency (cd / A) of the hybrid light-emitting device 100 of this application is about 161, which is about 41% higher than the current efficiency of existing light-emitting devices (about 114), and the operating lifetime (1000 nit T95) of the hybrid light-emitting device 100 is about 5600, which is about 70% higher than the operating lifetime of existing light-emitting devices (about 3300).

[0069] Understandably, the absorption peak position of quantum dots is determined by the quantum confinement effect. Smaller particle sizes result in a wider bandgap, leading to a blue shift in the absorption peak; larger particle sizes result in a red shift. Since the second emitting layer 151 contains two or more green quantum dots of different sizes, different sizes of green quantum dots correspond to different bandgap sizes, resulting in two or more discrete absorption peaks. Different sizes of green quantum dots correspond to specific characteristic absorption bands. Furthermore, since the first emitting layer 131 has multiple green emission peaks, and at least one of these peaks is located between the absorption peaks of the second emitting layer 151, hierarchical photoexcitation can be achieved. Therefore, when at least one emission peak of the first emitting layer 131 falls within the absorption peak range of the second emitting layer 151, efficient spectral coupling can be achieved. Photons of a specific wavelength emitted by the first emitting layer 131 can be directly and efficiently absorbed by quantum dots of the corresponding size, significantly improving energy transfer efficiency and reducing non-radiative losses. This allows the hybrid light-emitting device 100 to combine the advantages of long lifespan and high luminous efficiency.

[0070] Please see Figure 5 , Figure 5 This is a schematic diagram of the second layer structure of the hybrid light-emitting device disclosed in the first embodiment of this application. Figure 5 The hybrid light-emitting device shown is Figures 1 to 4 The difference between the hybrid light-emitting devices shown is: Figure 5 The first light-emitting unit 130 shown further includes a first energy level adjustment layer 135 and a first hole blocking layer (HBL) 136, and the second light-emitting unit 150 further includes a second energy level adjustment layer 155 and a second hole blocking layer 156. Regarding... Figure 5 The hybrid light-emitting device shown is Figures 1 to 4 For a description of the similarities between the hybrid light-emitting devices shown, please refer to [link / reference needed]. Figures 1 to 4 The relevant descriptions of hybrid light-emitting devices will not be repeated here.

[0071] In the embodiments of this application, such as Figure 5As shown, the first light-emitting unit 130 further includes a first energy level adjustment layer 135 and a first hole blocking layer 136. The first energy level adjustment layer 135 is disposed between the first light-emitting layer 131 and the first hole transport layer 133, and the first hole blocking layer 136 is disposed between the first light-emitting layer 131 and the first electron transport layer 134. The first energy level adjustment layer 135 is used to adjust the energy level matching of the first light-emitting layer 131 and to adjust the ability of charge carriers to be injected into the first light-emitting layer 131 from the first hole transport layer 133. For example, if there is an energy level difference between the first hole transport layer 133 and the first light-emitting layer 131, the first energy level adjustment layer 135 can serve as an intermediate energy level buffer layer to reduce the resistance of holes being injected into the first light-emitting layer 131 from the first hole transport layer 133, thereby improving the hole injection efficiency and reducing the device driving voltage. The first hole blocking layer 136 is used to block holes from passing through the first light-emitting layer 131 and entering the first electron transport layer 134, thus preventing hole loss. At the same time, electrons can pass through the first hole blocking layer 136 and enter the first light-emitting layer 131, achieving a balance between electron and hole injection in the first light-emitting layer 131. This allows electrons and holes to recombine and emit light in the first light-emitting layer 131, improving luminous efficiency and lifespan.

[0072] In this embodiment, the second light-emitting unit 150 further includes a second energy level adjustment layer 155 and a second hole blocking layer 156. The second energy level adjustment layer 155 is disposed between the second light-emitting layer 151 and the second hole transport layer 154, and the second hole blocking layer 156 is disposed between the second light-emitting layer 151 and the second electron transport layer 153. The second energy level adjustment layer 155 is used to adjust the energy level matching of the second light-emitting layer 151 and to adjust the ability of charge carriers to be injected into the second light-emitting layer 151 from the second hole transport layer 154. For example, if there is an energy level difference between the second hole transport layer 154 and the second light-emitting layer 151, the second energy level adjustment layer 155 can serve as an intermediate energy level buffer layer to reduce the resistance of holes being injected into the second light-emitting layer 151 from the second hole transport layer 154, thereby improving the hole injection efficiency and reducing the device driving voltage. The second hole blocking layer 156 is used to block holes from passing through the second light-emitting layer 151 and entering the second electron transport layer 153, thus preventing hole loss. At the same time, electrons can pass through the second hole blocking layer 156 and enter the second light-emitting layer 151, achieving a balance between electron and hole injection in the second light-emitting layer 151. This allows electrons and holes to recombine and emit light in the second light-emitting layer 151, thereby improving luminous efficiency and lifespan.

[0073] In this embodiment, the HOMO (Highest Occupied Molecular Orbital) energy levels of the first hole transport layer 133, the first energy level adjustment layer 135, and the first light-emitting layer 131 are arranged in a sequentially increasing gradient along the hole transport direction, and the HOMO energy level difference between two adjacent layers of the first hole transport layer 133, the first energy level adjustment layer 135, and the first light-emitting layer 131 is less than 0.3 eV.

[0074] Specifically, the HOMO energy levels of the first hole transport layer 133, the first energy level adjustment layer 135, and the first light-emitting layer 131 are arranged in the following order: the HOMO energy level of the first hole transport layer 133 is lower than that of the first energy level adjustment layer 135, and the HOMO energy level of the first energy level adjustment layer 135 is lower than that of the first light-emitting layer 131. Therefore, as holes transport from the first hole transport layer 133 to the first light-emitting layer 131, the energy level gradually rises, forming a gently ascending energy level step, and there is no reverse barrier hindering hole migration. Furthermore, the HOMO energy level difference between the first hole transport layer 133 and the first energy level adjustment layer 135 is less than 0.3 eV, and the HOMO energy level difference between the first energy level adjustment layer 135 and the first light-emitting layer 131 is also less than 0.3 eV. Therefore, by setting the HOMO energy level difference between adjacent layers, the hole injection resistance can be reduced, the device driving voltage can be lowered, and holes can be injected smoothly into the first light-emitting layer 131, which is beneficial for improving the device's lifespan.

[0075] In this embodiment of the application, the HOMO energy levels of the second hole transport layer 154, the second energy level adjustment layer 155 and the second light-emitting layer 151 are arranged in a sequentially increasing gradient along the hole transport direction, and the HOMO energy level difference between two adjacent layers of the second hole transport layer 154, the second energy level adjustment layer 155 and the second light-emitting layer 151 is less than 0.3 eV.

[0076] Specifically, the energy levels of the second hole transport layer 154, the second energy level adjustment layer 155, and the second emitting layer 151 are arranged in the following order: the HOMO energy level of the second hole transport layer 154 is lower than that of the second energy level adjustment layer 155, and the HOMO energy level of the second energy level adjustment layer 155 is lower than that of the second emitting layer 151. Furthermore, the HOMO energy level difference between the second hole transport layer 154 and the second energy level adjustment layer 155 is less than 0.3 eV, and the HOMO energy level difference between the second energy level adjustment layer 155 and the second emitting layer 151 is less than 0.3 eV. Therefore, by setting the HOMO energy levels in an increasing gradient along the hole transport direction and the HOMO energy level difference between adjacent layers, hole injection resistance can be reduced, the energy level difference between adjacent layers can be reduced, non-radiative energy loss can be reduced, and the gentle energy level gradient can evenly inject holes into quantum dots of various particle sizes.

[0077] In this embodiment, the LUMO (Lowest Unoccupied Molecular Orbital) energy level difference between the first hole-blocking layer 136 and the first light-emitting layer 131 is less than 0.2 eV, and the T1 energy level between the first hole-blocking layer 136 and the first light-emitting layer 131 can be greater than or equal to 2.5 eV and less than or equal to 3.3 eV. Similarly, the LUMO energy level difference between the second hole-blocking layer 156 and the second light-emitting layer 151 is less than 0.2 eV, and the T1 energy level between the second hole-blocking layer 156 and the second light-emitting layer 151 can be greater than or equal to 2.5 eV and less than or equal to 3.3 eV. Here, the T1 energy level is the lowest triplet excitation energy level of an organic molecule, referring to the lowest energy level formed by two excited-state electrons with parallel electron spins. Therefore, electrons are transported from the first electron transport layer 134 through the first hole blocking layer 136 to the first light-emitting layer 131, and electrons are transported from the second electron transport layer 153 through the second hole blocking layer 156 to the second light-emitting layer 151. Electrons do not accumulate at the interface between the hole blocking layer and the light-emitting layer. At the same time, electrons and holes are confined within the first light-emitting layer 131 and the second light-emitting layer 151, reducing non-radiative recombination loss and thus improving the luminous efficiency and working life of the hybrid light-emitting device 100.

[0078] In the embodiments of this application, the T1 energy levels of the first hole blocking layer 136 and the first light-emitting layer 131, as well as the T1 energy levels of the second hole blocking layer 156 and the second light-emitting layer 151, are all greater than or equal to 2.5 eV and less than or equal to 3.3 eV. For example, 2.5 eV, 2.6 eV, 2.8 eV, 2.85 eV, 2.9 eV, 2.95 eV, 3.0 eV, 3.2 eV, 3.25 eV, 3.3 eV, or other values ​​are not specifically limited in this application.

[0079] Understandably, the T1 energy levels of the first hole blocking layer 136 and the first light-emitting layer 131, and the T1 energy levels of the second hole blocking layer 156 and the second light-emitting layer 151, are preferably greater than or equal to 2.8 eV and less than or equal to 3.2 eV, for example, 2.8 eV, 2.82 eV, 2.85 eV, 2.9 eV, 2.95 eV, 3.0 eV, 3.1 eV, 3.15 eV, 3.2 eV, or other values. This application does not impose specific limitations on these values.

[0080] In this embodiment, the materials of the first energy level adjustment layer 135 and the second energy level adjustment layer 155 may be the same or different. The materials of the first hole blocking layer 136 and the second hole blocking layer 156 may be the same or different, and this application does not impose specific limitations on this.

[0081] Please see Figure 5 In one specific embodiment of this application, the first light-emitting layer 131 is doped with two green dopants, which, upon electroexcitation by an applied electric field, form two discrete green emission peaks (emission peaks) at 470 nm and 530 nm, respectively. The second light-emitting layer 151 contains green quantum dots of two different particle sizes. One particle size corresponds to an absorption peak at 470 nm and an emission peak at 525 nm, while the other particle size corresponds to an absorption peak at 490 nm and an emission peak at 545 nm. Therefore, under the action of an applied driving voltage, the first light-emitting layer 131 directly emits green light through electroluminescence. Part of this green light passes through the charge generation layer 140 along the emission direction and enters the second light-emitting layer 151, exciting the second light-emitting layer 151 to produce green light. Thus, the target color light emitted by the hybrid light-emitting device 100 along the emission direction is green light. Therefore, Figure 5 The hybrid light-emitting device 100 shown, after adding the first energy level adjustment layer 135 and the second energy level adjustment layer 155, has a current efficiency (cd / A) of approximately 173 and an operating lifetime (1000 nit T95) of approximately 5700, compared to... Figures 1 to 4The hybrid light-emitting device 100 shown has an improved current efficiency (approximately 161) of about 7% and an improved operating lifetime (approximately 5600) of about 1.7%. Figure 5 The hybrid light-emitting device 100 shown, after adding the first hole-blocking layer 136 and the second hole-blocking layer 156, has a current efficiency (cd / A) of approximately 172 and a lifetime (1000 nit T95) of approximately 6100, compared to... Figures 1 to 4 The hybrid light-emitting device 100 shown has an improved current efficiency (approximately 161) of about 6.8% and an improved operating lifetime (approximately 5600) of about 8.9%. Figure 5 The hybrid light-emitting device 100 shown, after simultaneously adding the first energy level adjustment layer 135 and the second energy level adjustment layer 155, as well as the first hole blocking layer 136 and the second hole blocking layer 156, has a current efficiency (cd / A) of approximately 182 and a service life (1000 nit T95) of approximately 6200, compared to... Figures 1 to 4 The hybrid light-emitting device 100 shown has an improved current efficiency (approximately 161) of approximately 13% and an improved operating lifetime (approximately 5600) of approximately 10.7%.

[0082] In summary, the hybrid light-emitting device 100 provided in this application includes a substrate 110, a first electrode layer 120, a first light-emitting unit 130, a charge-generating layer 140, a second light-emitting unit 150, and a second electrode layer 160. The first electrode layer 120, the first light-emitting unit 130, the charge-generating layer 140, the second light-emitting unit 150, and the second electrode layer 160 are stacked on the substrate 110 along the light-emitting direction. The first light-emitting unit 130 includes at least one first light-emitting layer 131, and the second light-emitting unit 150 includes a second light-emitting layer 151. Under the action of a driving voltage, the first light-emitting layer 131 emits a first color light. Part of the first color light passes through the charge-generating layer 140 and is incident on the second light-emitting layer 151, exciting the second light-emitting layer 151 to generate a second color light, so that the hybrid light-emitting device 100 emits a target color light. Therefore, the hybrid light-emitting device 100 of this application uses the first light-emitting unit 130 and the second light-emitting unit 150 in series, and achieves hybrid excitation and light emission by utilizing the electroluminescence of the first light-emitting layer 131 and the photoluminescence of the second light-emitting layer 151. This improves the overall luminous efficiency, lifespan, and operational stability of the hybrid light-emitting device 100, thereby enhancing the display effect and user experience. It fundamentally solves the problems of short lifespan of OLED devices and low luminous efficiency caused by high power consumption at low current densities. Moreover, the hybrid light-emitting device 100 has a simple overall structure, advantages in mass production and cost, and broad application prospects.

[0083] Based on the same inventive concept, a second embodiment of this application also provides a display panel. Please refer to... Figure 6 , Figure 6 This is a partial top view of the display panel disclosed in the second embodiment of this application. The display panel 30 provided in this embodiment includes the aforementioned hybrid light-emitting device 100. The display panel 30 may include an array of multiple hybrid light-emitting devices 100 as described above.

[0084] Please see Figure 6In this embodiment, the display panel 30 includes a plurality of sub-pixel regions A1 and non-sub-pixel regions A2. The plurality of sub-pixel regions A1 are arranged in an array, that is, the plurality of sub-pixel regions A1 are arranged in multiple rows along a first direction 001 and in multiple columns along a second direction 002 perpendicular to the first direction 001. The plurality of sub-pixel regions A1 are spaced apart from each other, and the sub-pixel regions A1 are used to emit display light. The non-sub-pixel regions A2 are disposed around the periphery of the plurality of sub-pixel regions A1, that is, the areas between the plurality of sub-pixel regions A1 belong to the non-sub-pixel regions A2. The number of sub-pixel regions A1 is determined by the resolution of the display panel 30, and this application does not impose a specific limitation on this.

[0085] Based on the same inventive concept, the third embodiment of this application also provides a display device. Please refer to... Figure 7 , Figure 7 This is a schematic diagram of the structure of the display device disclosed in the third embodiment of this application. The display device 1 provided in this embodiment may include a housing 10 and the aforementioned display panel 30. The display panel 30 is disposed within the housing 10 and is detachably connected to the housing 10, with the light-emitting side of the display panel 30 exposed outside the housing 10. The housing 10 serves as a structural frame and may be made of metal or plastic. The display panel 30 is used to display images.

[0086] Understandably, the display device 1 can be used in electronic devices including, but not limited to, televisions, tablets, laptops, smart home appliances, desktop computers, mobile phones, in-vehicle displays, smartwatches, smart bracelets, smart glasses, road signs, medical imaging devices, and other electronic devices. According to the embodiments of this application, the specific type of the display device 1 is not particularly limited, and those skilled in the art can design it accordingly based on the specific usage requirements of the display device 1; further details will not be elaborated here.

[0087] In other embodiments of this application, the display device 1 may further include a processor and a memory. The processor is electrically connected to the display panel 30 and is used to control the display panel 30 to display content. The memory is electrically connected to the processor and is used to store program code required for the processor to run, control the display content of the display panel 30, etc.

[0088] In an exemplary embodiment, the memory may include volatile memory, such as random access memory (RAM); the memory may also include non-volatile memory (NVM), such as read-only memory (ROM), flash memory (FM), hard disk drive (HDD), or solid-state drive (SSD). The memory may also include combinations of the above types of memory.

[0089] In an exemplary embodiment, the processor includes one or more general-purpose processors, wherein the general-purpose processor can be any type of device capable of processing electronic instructions, including a central processing unit (CPU), microprocessor, microcontroller, main processor, and controller, etc. The processor is used to execute various types of digital storage instructions, such as software or firmware programs stored in the memory, which enable the computing device to provide a wide range of services.

[0090] In an exemplary embodiment, the display device 1 may also include other necessary components and parts such as a driver board, a power board, a high-voltage board, and a button control board. Those skilled in the art can make corresponding additions according to the specific type and actual function of the display device 1, which will not be elaborated here.

[0091] In summary, in the display panel 30 and display device 1 provided in this application embodiment, the display device 1 includes a housing 10 and a display panel 30, with the display panel 30 disposed on the housing 10. The display panel 30 includes a hybrid light-emitting device 100, which includes a substrate 110, a first electrode layer 120, a first light-emitting unit 130, a charge-generating layer 140, a second light-emitting unit 150, and a second electrode layer 160. The first electrode layer 120, the first light-emitting unit 130, the charge-generating layer 140, the second light-emitting unit 150, and the second electrode layer 160 are stacked on the substrate 110 along the light-emitting direction. The first light-emitting unit 130 includes at least one first light-emitting layer 131, and the second light-emitting unit 150 includes a second light-emitting layer 151. Under the action of a driving voltage, the first light-emitting layer 131 emits light of a first color. Part of the first color light passes through the charge-generating layer 140 and is incident on the second light-emitting layer 151, exciting the second light-emitting layer 151 to generate light of a second color, thereby causing the hybrid light-emitting device 100 to emit light of the target color. Therefore, the hybrid light-emitting device 100 of this application uses the first light-emitting unit 130 and the second light-emitting unit 150 in series, utilizing the electroluminescence of the first light-emitting layer 131 and the photoluminescence of the second light-emitting layer 151 to achieve hybrid excitation and emission, improving the overall luminous efficiency, lifespan, and operational stability of the hybrid light-emitting device 100. This fundamentally solves the problems of short lifespan of OLED devices and low luminous efficiency caused by high power consumption at low current densities, thereby improving the display effect and user experience of the display panel 30 and the display device 1. Furthermore, the hybrid light-emitting device 100 has a simple overall structure, advantages in mass production and cost, and broad application prospects.

[0092] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0093] It should be understood that the application of this application is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims. Those skilled in the art will understand that implementing all or part of the processes of the above embodiments, and making equivalent changes according to the claims of this application, still falls within the scope of this application.

Claims

1. A hybrid light-emitting device, comprising a substrate, a first electrode layer, and a second electrode layer, characterized in that, The hybrid light-emitting device further includes a first light-emitting unit, a charge-generating layer, and a second light-emitting unit. The first electrode layer, the first light-emitting unit, the charge-generating layer, the second light-emitting unit, and the second electrode layer are stacked on the substrate along the light-emitting direction. The first light-emitting unit includes at least one first light-emitting layer, and the second light-emitting unit includes a second light-emitting layer. The first light-emitting layer emits a first color light under the action of a driving voltage. Part of the first color light passes through the charge-generating layer and is incident on the second light-emitting layer, exciting the second light-emitting layer to generate a second color light, so that the hybrid light-emitting device emits a target color light.

2. The hybrid light-emitting device as described in claim 1, characterized in that, The first light-emitting unit further includes a hole injection layer, a first hole transport layer, and a first electron transport layer. The hole injection layer is disposed on the side of the first electrode layer facing the first light-emitting layer. The first hole transport layer is disposed between the hole injection layer and the first light-emitting layer. The first electron transport layer is located between the first light-emitting layer and the charge generation layer. The second light-emitting unit further includes an electron injection layer, a second electron transport layer, and a second hole transport layer. The electron injection layer is disposed on the side of the second electrode layer facing the second light-emitting layer. The second electron transport layer is located between the electron injection layer and the second light-emitting layer. The second hole transport layer is located between the second light-emitting layer and the charge generation layer.

3. The hybrid light-emitting device as described in claim 2, characterized in that, The charge generation layer is disposed between the first light-emitting unit and the second light-emitting unit. The charge generation layer includes a first sub-charge generation layer and a second sub-charge generation layer stacked together. The first sub-charge generation layer is disposed on the side of the first electron transport layer of the first light-emitting unit that faces away from the first electrode layer. The second sub-charge generation layer is disposed on the side of the second hole transport layer of the second light-emitting unit that faces away from the second electrode layer. The first sub-charge generation layer is used to generate electrons and inject electrons into the first light-emitting layer. The second sub-charge generation layer is used to generate holes and inject holes into the second light-emitting layer.

4. The hybrid light-emitting device as described in claim 3, characterized in that, The first sub-charge generation layer is an N-type charge generation layer, and the second sub-charge generation layer is a P-type charge generation layer. Both the first and second sub-charge generation layers contain metal nanowires.

5. The hybrid light-emitting device as described in claim 1, characterized in that, The hybrid light-emitting device further includes an optical adjustment layer, which is disposed on the side of the second electrode layer opposite to the second light-emitting unit. The optical adjustment layer is used to perform optical modulation on the hybrid light-emitting device.

6. The hybrid light-emitting device as described in claim 1, characterized in that, The first emitting layer comprises at least two blue dopants and has at least two discrete emission peaks; the second emitting layer comprises yellow quantum dots of a single particle size and has one absorption peak; the first color light may be blue light, the second color light may be yellow light, and the target color light may be white light; or... The first luminescent layer comprises at least two dopants of any color chosen from red, green, and blue, and has at least two discrete emission peaks; the second luminescent layer comprises quantum dots of at least one particle size of the same color as the first luminescent layer, and has at least one absorption peak; or, The first light-emitting layer comprises at least two dopants of any color selected from red, green, and blue, and has at least two discrete emission peaks; the second light-emitting layer comprises quantum dots of at least two particle sizes of the same color as the first light-emitting layer, and has at least two discrete absorption peaks; wherein at least one emission peak of the first light-emitting layer is located between the absorption peaks of the second light-emitting layer.

7. The hybrid light-emitting device according to any one of claims 1-6, characterized in that, The first light-emitting unit further includes a first energy level adjustment layer and a first hole blocking layer. The first energy level adjustment layer is disposed between the first light-emitting layer and the first hole transport layer, and the first hole blocking layer is disposed between the first light-emitting layer and the first electron transport layer. The first energy level adjustment layer is used to adjust the energy level matching of the first light-emitting layer and adjust the ability of charge carriers to be transported from the first hole into the first light-emitting layer. The first hole blocking layer is used to block holes from passing through the first light-emitting layer and entering the first electron transport layer. The second light-emitting unit includes a second energy level adjustment layer and a second hole blocking layer. The second energy level adjustment layer is disposed between the second light-emitting layer and the second hole transport layer, and the second hole blocking layer is disposed between the second light-emitting layer and the second electron transport layer. The second energy level adjustment layer is used to adjust the energy level matching of the second light-emitting layer and adjust the ability of charge carriers to be transported from the second hole into the second light-emitting layer. The second hole blocking layer is used to block holes from passing through the second light-emitting layer and entering the second electron transport layer.

8. The hybrid light-emitting device as described in claim 7, characterized in that, The HOMO energy levels of the first hole transport layer, the first energy level adjustment layer, and the first light-emitting layer are arranged in a gradient increasing order. The HOMO energy level difference between the first hole transport layer and the first energy level adjustment layer is less than 0.3 eV, and the HOMO energy level difference between the first energy level adjustment layer and the first light-emitting layer is less than 0.3 eV. The HOMO energy levels of the second hole transport layer, the second energy level adjustment layer, and the second light-emitting layer are arranged in a sequentially increasing gradient. The HOMO energy level difference between the second hole transport layer and the second energy level adjustment layer is less than 0.3 eV, and the HOMO energy level difference between the second energy level adjustment layer and the second light-emitting layer is less than 0.3 eV. The LUMO energy level difference between the first hole blocking layer and the first light-emitting layer is less than 0.2 eV, and the T1 energy level between the first hole blocking layer and the first light-emitting layer is greater than or equal to 2.5 eV and less than or equal to 3.3 eV; the LUMO energy level difference between the second hole blocking layer and the second light-emitting layer is less than 0.2 eV, and the T1 energy level between the second hole blocking layer and the second light-emitting layer is greater than or equal to 2.5 eV and less than or equal to 3.3 eV.

9. A display panel, characterized in that, Including the hybrid light-emitting device as described in any one of claims 1-8.

10. A display device, characterized in that, It includes a housing and a display panel as described in claim 9, wherein the display panel is disposed within the housing.

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