[0018] In order to make the objectives, technical solutions, and advantages of the present invention clearer, the following further describes the present invention in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present invention, but not to limit the present invention.
[0019] Combine Figure 1-Figure 3 , The embodiment of the present invention provides a QLED, such as figure 1 As shown, it includes a substrate 1, a bottom electrode 2, a quantum dot light-emitting layer 3, and a top electrode 4 arranged in sequence. The quantum dot light-emitting layer 3 consists of a mesoporous material 31 and an electrolyte 32 and a light-emitting quantum dot filled in the pores of the mesoporous material 31. 33 composition (see figure 2 or image 3 ), where the conductivity of the electrolyte 32 is ≥0.01scm -1.
[0020] In the embodiments of the present invention, QLED devices are not limited to top emission or bottom emission; nor are they limited to positive type devices or inverted type devices.
[0021] In the embodiment of the present invention, the mesoporous material 31 refers to a porous material with semiconductor-level conductivity, and is responsible for providing a carrier (electron or hole) to the light-emitting quantum dot 33. On the one hand, the mesoporous material 31 has extremely high specific surface area, regular and orderly pore structure, narrow pore size distribution, continuously adjustable pore size, etc., which help to enhance the quantum size effect of the quantum dot light-emitting layer 3; Selecting an appropriate conductivity can make it more effective to provide carriers for the light-emitting quantum dot 33 and enhance the luminous efficiency of the quantum dot light-emitting layer 3. Preferably, the conductivity of the mesoporous material 31 is selected to be 1*10 -6 ~1*10 -2 scm -1.
[0022] In the embodiment of the present invention, the mesoporous material 31 may specifically be a material with mesoporous properties such as oxide or carbon material, preferably, it may be Al 2 O 3 , Nb 2 O 5 , Ta 2 O 5 , TiO 2 , ZnO, ZrO 2 , At least one of carbon element.
[0023] In the embodiment of the present invention, since the pores of the mesoporous material 31 are used to fill the electrolyte 32 and the light-emitting quantum dots 33, the volume content of the pores in the mesoporous material 31 and the pore line degree are important for the filled electrolyte 32 and light-emitting quantum dots. The content of 33 has a greater influence. Preferably, based on the total volume of the mesoporous material 31 as 100%, the volume percentage of the pores is between 20%-100%, but less than 100%; preferably, the linearity of the pores It is 2-50nm.
[0024] In the embodiment of the present invention, the electrolyte 32 is mixed with the light-emitting quantum dots 33 and filled into the pores of the mesoporous material 31 as a filler. The electrolyte 32 is responsible for providing another type of carrier (the type of carrier) to the light-emitting quantum dots 33. Corresponding to the type of carriers provided by the mesoporous material 31, specifically, when the type of carriers provided by the mesoporous material 31 is electrons, the type of carriers provided by the electrolyte 32 is holes; when the mesoporous material 31 When the type of carriers provided is holes, the type of carriers provided by the electrolyte 32 is electrons, so as to reduce the external electric field that the light-emitting quantum dots 33 bear in the working state.
[0025] In the embodiment of the present invention, since the electrolyte 32 is used to provide carriers, the conductivity of the electrolyte 32 has a greater influence on the concentration of carriers provided to the light-emitting quantum dots 33. Therefore, the electrolyte 32 needs to have a high conductivity. At the same time, due to the addition of the electrolyte 32 with high conductivity, the conductivity of the quantum dot light-emitting layer 3 is improved, and the thickness of the light-emitting layer is no longer limited by its own low conductivity. Preferably, the conductivity of the electrolyte 32 is ≥0.01 scm -1 When the electrolyte 32 and the light-emitting quantum dot 33 under this conductivity condition are mixed and the pores of the mesoporous material 31 are fully filled, the applied voltage of the entire quantum dot light-emitting layer 3 in the working state can be ignored; at the same time, The thickness of the quantum dot light-emitting layer 3 is not limited to one hundred nanometers or even several hundred nanometers, thereby increasing the effective microcavity length of the device and improving the luminous efficiency of the device (when the effective microcavity length of the device and the half wavelength of the emitted light When the integer multiple of is equal, the microcavity effect can be used to improve the light extraction efficiency, where the emission wavelength is 500-700nm).
[0026] In the embodiment of the present invention, the electrolyte 32 may specifically be at least one of an ion and organic solvent-based electrolyte 32, a solid-like sol-gel electrolyte 32, and a solid electrolyte 32, but is not limited to the foregoing materials. Specifically, the electrolyte 32 based on ions and organic solvents may be 1 - /I 3 - Electrolyte 32; solid-like sol-gel electrolyte 32 can be PVDF-HFP (polyvinylidenefluoride-co-hexafluoropropylene) cured based on MPN (3-methoxypropionitrile, 3- Methoxypropionitrile) liquid electrolyte 32; solid electrolyte 32 can be Y-doped ZrO 2 Ionic conductor (TSZ), b-Al 2 O 3 Ionic conductor, LaF 3 Fluoride-containing ion conductors, AgI and other iodine ion conductors.
[0027] In the embodiment of the present invention, the light-emitting quantum dots 33 are mixed with the electrolyte 32 and filled into the pores of the mesoporous material 31 as a filler, and the light-emitting quantum dots 33 are used as the light-emitting material to electroluminescence. The light-emitting quantum dots 33 can be nanocrystals of II-VI semiconductors, nanocrystals of III-V semiconductors, II-V compounds, III-VI compounds, IV-VI compounds, I-III-VI compounds, II-VI At least one of IV-VI compounds and IV elemental substances, but not limited to the aforementioned materials. Among them, the II-VI semiconductor nanocrystals may specifically be at least one of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, CdZnS, CdZnSe, CdZnSeS and other binary, ternary, and quaternary II-VI compounds; The nanocrystal of III-V semiconductor may be at least one of GaP, GaAs, InP, InAs, and other binary, ternary, and quaternary III-V compounds.
[0028] In the embodiment of the present invention, the surface of the light-emitting quantum dot 33 is covered with a passivation layer to passivate defects on the surface of the quantum dot and enhance its luminous efficiency. Specifically, the passivation layer may be formed by covering the surface of the quantum dot with an organic ligand or an inorganic ligand.
[0029] In the embodiment of the present invention, the selection of the substrate 1 is not limited, and a flexible substrate or a rigid substrate can be used. The hard substrate may specifically be a glass substrate.
[0030] In the embodiment of the present invention, the bottom electrode 2 can be made of a conventional anode material. Preferably, the bottom electrode 2 may be at least one of conductive metal oxide, graphene, carbon nanotube, high work function metal, and conductive polymer.
[0031] In the embodiment of the present invention, the top electrode 4 can be a conventional cathode material, preferably, it can be at least one of Al, Ag, Ca, Ba, and Mg.
[0032] The QLED provided by the embodiment of the present invention includes three functional layers: a bottom electrode 2, a quantum dot light-emitting layer 3, and a top electrode 4, wherein the quantum dot light-emitting layer 3 uses conductivity ≥ 0.01 scm -1 The electrolyte 32 fully fills the pores of the mesoporous material 31 so that the local electric field that the quantum dot 33 should bear under electroluminescence conditions is shielded, thereby improving the luminous efficiency and service life of the device; on the other hand, due to the electrolyte 32 The addition of the light-emitting layer makes the thickness of the light-emitting layer no longer limited by its own low conductivity, and the thickness can reach one hundred nanometers or even several hundred nanometers, which reduces the thickness control cost, and makes the effective microcavity length of the device close to the half wavelength of the emitted light An integer multiple of, and the device can effectively use the microcavity effect to improve the luminous efficiency again.
[0033] An embodiment of the present invention also provides a display device, which includes the above QLED device.
[0034] The QLED of the embodiment of the present invention can be prepared by the following method.
[0035] Accordingly, combine Figure 4 , The embodiment of the present invention provides a manufacturing method based on the above QLED, including the following steps:
[0036] Step S01: Provide a substrate and deposit a bottom electrode.
[0037] Step S02: Prepare mesoporous material on the bottom electrode, combine the light-emitting quantum dots and the conductivity ≥0.01scm -1 The electrolyte is mixed and filled into the pores of the mesoporous material to form a quantum dot light-emitting layer.
[0038] Step S03: deposit a top electrode on the quantum dot light-emitting layer.
[0039] The selection and preferred types of the materials of each layer in the embodiment of the present invention are as described above. In order to save space, the details are not repeated here.
[0040] The method for preparing the QLED device provided by the embodiment of the present invention is to prepare a mesoporous material on the bottom electrode, mix the light-emitting quantum dots and electrolyte and fill the pores of the mesoporous material, and deposit the top electrode. The method is simple and easy to control. Better application prospects.
[0041] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modification, equivalent replacement and improvement made within the spirit and principle of the present invention shall be included in the protection scope of the present invention. Inside.
