Erbium-ytterbium co-doped perovskite near-infrared light-emitting quantum dot film and preparation method and application thereof

Abstract

The invention discloses an erbium-ytterbium co-doped perovskite near-infrared light-emitting quantum dot film, a preparation method of the erbium-ytterbium co-doped perovskite near-infrared light-emitting quantum dot film and an application of the erbium-ytterbium co-doped perovskite near-infrared light-emitting quantum dot film, and belongs to the technical field of preparation of novel electronic components. According to the erbium / ytterbium co-doped perovskite quantum dot and the preparation method thereof, the defect that traditional organic ligands (oleyl ammonia, oleic acid and octadecene) are weak in polarity and have adverse effects on carrier transport performance in the process of growing nanocrystals through a current thermal injection method is overcome, the environmental stability and size uniformity of perovskite quantum dots are improved, and the near-infrared luminous efficiency of the erbium / ytterbium co-doped perovskite quantum dot at the positions of 990nm and 1540nm is remarkably improved. Meanwhile, under the action of diallyl thiosulfinate, the quantum dots are orderly and compactly arranged in the process of spin-coating to form a light-emitting layer film, so that the flatness and film forming quality of the film are improved, and the external quantum efficiency of the prepared near-infrared light-emitting diode is 8.7% at 986nm and 1.2% at 1540nm; the highest efficiency of an erbium / ytterbium co-doped perovskite light-emitting diode is achieved at present. The near-infrared light-emitting diode can emit light in a near-infrared band, so that the near-infrared light-emitting diode can be applied to the fields of medical imaging, optical communication and the like.

Description

Technical Field

[0001] The present invention belongs to the technical field of novel electronic component preparation, and in particular relates to an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film and a preparation method and application thereof. Background Art

[0002] All-inorganic perovskite quantum dots are used in the optoelectronic field because of their advantages such as high photoluminescence quantum yield, large absorption cross section, narrow emission peak, and adjustable band gap. They are widely used in many fields such as lighting, display, photovoltaics, and imaging. However, due to the problem that perovskite quantum dots emit light only in the visible light region, their development in practical applications is limited. Rare earth ions have rich 4f-5d energy levels, which makes their emission positions cover the spectral range from ultraviolet to infrared. Doping rare earth ions in perovskite quantum dots can not only improve and expand the optoelectronic properties of perovskites, but also broaden the emission position to the near-infrared or even mid-infrared range, thereby solving some key problems of perovskite nanomaterials facing reality. Among them, doping ytterbium ions and erbium ions into all-inorganic lead halide perovskite quantum dots can utilize the "quantum tailoring" characteristics of ytterbium ions and energy transfer to erbium ions to achieve near-infrared dual emission at 990nm and 1540nm. However, the low efficiency of energy transfer from excitons to rare earth ions and the limited application scenarios of near-infrared luminescence stimulated by light have hindered the further practical application of near-infrared luminescence from rare earth ions. Near-infrared light in the 900nm-1600nm band has important applications in medical imaging, photonic chips, and optical communications. However, the III-V semiconductor light-emitting diodes and organic light-emitting diodes that can currently achieve electroluminescence in this band have low efficiency, complex processes, and are expensive. Therefore, there is an urgent need to use ytterbium ions and erbium ions to co-dope lead halide perovskites to achieve near-infrared light emission, and to prepare near-infrared light-emitting diodes to achieve high-efficiency, low-cost electroluminescence near-infrared luminescence. Summary of the invention

[0003] The purpose of the present invention is to provide an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film and a preparation method and application thereof, so as to solve the problems existing in the above-mentioned prior art.

[0004] One of the technical solutions provided by the present invention:

[0005] A method for preparing an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film comprises mixing a diallyl thiosulfinate organic solution and an erbium / ytterbium co-doped perovskite quantum dot solution to obtain an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot solution, and spin-coating the erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot solution on a substrate to obtain the erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film.

[0006] Preferably, the spin coating speed is 2000 r / min and the spin coating time is 30 s.

[0007] Preferably, the volume ratio of the diallyl thiosulfinate organic solution to the erbium / ytterbium co-doped perovskite quantum dot solution is 0.03:1.

[0008] More preferably, the concentration of the diallyl thiosulfinate organic solution is 0.8 mg / mL.

[0009] More preferably, the preparation method of the erbium / ytterbium co-doped perovskite quantum dot solution comprises the following steps: in a nitrogen atmosphere, heating and stirring a mixed solution of cesium carbonate, oleic acid and octadecene until completely dissolved, heating to 100-150°C and stirring for 0.5-1h to obtain a perovskite precursor solution; in a nitrogen atmosphere, heating and stirring a mixed solution of lead chloride, lead bromide, erbium chloride hexahydrate, ytterbium chloride hexahydrate, oleic acid, oleyl ammonia and octadecene until completely dissolved, heating to 150°C and keeping warm for 1h, then heating to 270°C and keeping for 5min, rapidly injecting the perovskite precursor solution, cooling to room temperature, centrifuging, adding a mixed solution of ethyl acetate and toluene to the precipitate, centrifuging again after dissolution, dissolving the precipitate in toluene, standing for stratification, and taking the supernatant, which is the erbium / ytterbium co-doped perovskite quantum dot solution.

[0010] More preferably, the usage ratio of cesium carbonate, oleic acid and octadecene is 0.2 g:0.7 mL:7 mL.

[0011] More preferably, the usage ratio of lead chloride, lead bromide, erbium chloride hexahydrate, ytterbium chloride hexahydrate, oleic acid, oleylamine, octadecene and perovskite precursor is 0.06g:0.02g:0.027g:0.053g:2mL:2mL:10mL:1mL.

[0012] The second technical solution provided by the present invention is:

[0013] The above preparation method can prepare an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film.

[0014] The third technical solution provided by the present invention is:

[0015] An application of the above-mentioned erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film in the preparation of electronic components.

[0016] The fourth technical solution provided by the present invention is:

[0017] A light-emitting diode containing the above-mentioned erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film, which includes, from bottom to top, a transparent conductive glass substrate, a hole injection layer, a hole transport layer, a perovskite luminescent layer, an electron transport and hole blocking layer, a buffer layer and a metal cathode layer; the perovskite luminescent layer is an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film layer. When a forward voltage is applied between the positive and negative electrodes, the light-emitting diode emits 986nm near-infrared characteristic fluorescence of ytterbium ions and 1540nm near-infrared characteristic fluorescence of erbium ions.

[0018] Wherein, the material used for the hole injection layer is selected from PEDOT:PSS or MoO3, and the thickness of the hole injection layer is 20-30nm.

[0019] The hole transport layer is made of a material selected from PVK, Poly-TPD or NiOx, and the thickness of the hole transport layer is 40-50 nm.

[0020] The material used for the electron transport and hole blocking layer is selected from TPBi or BmPyPhB, and the thickness of the electron transport and hole blocking layer is 40-50nm.

[0021] The metal cathode layer is a composite cathode composed of LiF and metal, and the metal is selected from Ag, Al or Au.

[0022] Compared with the prior art, the present invention has the following advantages and technical effects:

[0023] The present invention overcomes the weak polarity of traditional organic ligands (oleyl ammonia, oleic acid, octadecene) in the process of growing nanocrystals by the current hot injection method, and the adverse effects on carrier transport performance, improves the environmental stability and size uniformity of perovskite quantum, and significantly improves the near-infrared luminous efficiency of erbium / ytterbium co-doped perovskite quantum dots at 990nm and 1540nm. At the same time, under the action of diallyl thiosulfinate, the quantum dots are arranged in an orderly and dense manner during spin coating into a light-emitting layer film, which improves the flatness and film-forming quality of the film, and the external quantum efficiency of the near-infrared light-emitting diode prepared thereby is 8.7% at 986nm and 1.2% at 1540nm, which is the highest efficiency of the current erbium / ytterbium co-doped perovskite light-emitting diode. The near-infrared light-emitting diode can be used in the fields of medical imaging, optical communication, etc. because it can emit in the near-infrared band. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0025] Figure 1 The erbium / ytterbium co-doped titanium ore (Er 3+ / Yb 3+ :CsPbCl 2.7 Br 0.3 ) Transmission electron microscopy of near-infrared luminescent quantum dots;

[0026] Figure 2 a) is a scanning electron microscope of the erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film prepared in Example 1, and b) is an atomic force microscope thereof;

[0027] Figure 3 Schematic diagram of the structure of the light-emitting diode device prepared in Application Example 1, wherein 1 is a transparent conductive glass substrate, 2 is a hole injection layer, 3 is a hole transport layer, 4 is a perovskite light-emitting layer, 5 is an electron transport and hole blocking layer, 6 is a buffer layer, and 7 is a metal cathode layer;

[0028] Figure 4 This is the photoluminescence spectrum of erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film;

[0029] Figure 5 The electroluminescence spectrum of the light-emitting diode device prepared in Application Example 1;

[0030] Figure 6 The voltage-current density characteristic curve of the light-emitting diode prepared in Application Example 1;

[0031] Figure 7 The voltage-power density characteristic curves of the light-emitting diode prepared in Application Example 1 at 986 nm (a) and 1540 nm (b);

[0032] Figure 8 The voltage-external quantum efficiency curves of the light-emitting diode prepared in Application Example 1 at 986 nm (a) and 1540 nm (b);

[0033] Fig. 9 This is a transmission electron microscope of the erbium / ytterbium co-doped perovskite quantum dots prepared in Comparative Example 1;

[0034] Fig.10 The electroluminescence spectrum of the light-emitting diode device prepared in Application Example 2;

[0035] Fig.11 The voltage-current density characteristic curve of the light-emitting diode prepared in Application Example 2;

[0036] Fig.12 The voltage-power density characteristic curves of the light-emitting diode prepared in Application Example 2 at 986 nm (a) and 1540 nm (b);

[0037] Fig.13 The voltage-external quantum efficiency curves of the light-emitting diode prepared in Application Example 2 at 986 nm (a) and 1540 nm (b). DETAILED DESCRIPTION

[0038] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0039] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0040] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0041] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to the skilled artisan. The present invention description and examples are exemplary only.

[0042] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0043] The room temperature in the present invention refers to 25±2°C.

[0044] The embodiment of the present invention provides a method for preparing an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film, wherein a diallyl thiosulfinate organic solution and an erbium / ytterbium co-doped perovskite quantum dot solution are mixed to obtain an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot solution, and the erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot solution is spin-coated on a substrate to obtain the erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film. The spin-coating speed is 2000 r / min, and the spin-coating time is 30 s.

[0045] In some embodiments of the present invention, the volume ratio of the diallyl thiosulfinate organic solution to the erbium / ytterbium co-doped perovskite quantum dot solution is 30 μL:1 mL.

[0046] In some embodiments of the present invention, the concentration of the diallyl thiosulfinate organic solution is 0.8 mg / mL.

[0047] In some embodiments of the present invention, the preparation method of the erbium / ytterbium co-doped perovskite quantum dot solution comprises the following steps: in a nitrogen atmosphere, heating and stirring a mixed solution of cesium carbonate, oleic acid and octadecene until completely dissolved, heating to 100-150°C and stirring for 0.5-1h to obtain a perovskite precursor solution; in a nitrogen atmosphere, heating and stirring a mixed solution of lead chloride, lead bromide, erbium chloride hexahydrate, ytterbium chloride hexahydrate, oleic acid, oleyl ammonia and octadecene until completely dissolved, heating to 150°C and keeping warm for 1h, then heating to 270°C and keeping for 5min, rapidly injecting the perovskite precursor solution, cooling to room temperature, centrifuging, adding a mixed solution of ethyl acetate and toluene to the precipitate, centrifuging again after dissolution, dissolving the precipitate in toluene, standing for stratification, and taking the supernatant, which is the erbium / ytterbium co-doped perovskite quantum dot solution.

[0048] In some embodiments of the present invention, the usage ratio of cesium carbonate, oleic acid and octadecene is 0.2 g: 0.7 mL: 7 mL.

[0049] In some embodiments of the present invention, the usage ratio of lead chloride, lead bromide, erbium chloride hexahydrate, ytterbium chloride hexahydrate, oleic acid, oleyl ammonia, octadecene and perovskite precursor is 0.06g:0.02g:0.027g:0.053g:2mL:2mL:10mL:1mL.

[0050] The embodiment of the present invention also provides an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film prepared by the above preparation method.

[0051] An embodiment of the present invention also provides an application of the above-mentioned erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film in the preparation of electronic components.

[0052] An embodiment of the present invention also provides a light-emitting diode containing the above-mentioned erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film, which includes, from bottom to top, a transparent conductive glass substrate, a hole injection layer, a hole transport layer, a perovskite light-emitting layer, an electron transport and hole blocking layer, a buffer layer and a metal cathode layer; the perovskite light-emitting layer is an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film layer.

[0053] In some embodiments of the present invention, the hole injection layer is made of a material selected from PEDOT:PSS or MoO3, and has a thickness of 20-30 nm. In a preferred embodiment, the hole injection layer is made of PEDOT:PSS, and has a thickness of 30 nm.

[0054] In some embodiments of the present invention, the hole transport layer is made of a material selected from PVK, Poly-TPD or NiO x , with a thickness of 40-50nm. In a preferred embodiment, the material used is PVK, with a thickness of 40nm.

[0055] In some embodiments of the present invention, the electron transport and hole blocking layer is made of a material selected from TPBi or BmPyPhB, and has a thickness of 40-50 nm. In a preferred embodiment, the material used is TPBi, and has a thickness of 45 nm.

[0056] In some embodiments of the present invention, the metal cathode layer is a composite cathode composed of LiF and metal, and the metal is selected from Ag, Al or Au. In a preferred embodiment, the metal is Ag.

[0057] The reagents and raw materials required in the examples of the present invention are all purchased from commercial sources.

[0058] When preparing the erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film in the embodiment of the present invention, cesium carbonate, erbium chloride hexahydrate and ytterbium chloride hexahydrate need to be placed in a vacuum drying oven and dried for 24 hours to remove adsorbed water molecules.

[0059] Example 1 A method for preparing an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film,

[0060] (1) 0.2 g CsCO3 and 0.7 mL OA (oleic acid) were added to 7 mL ODE (octadecene), heated to 120 °C under nitrogen protection and stirred for 1 h to obtain a clear perovskite precursor;

[0061] (2) 0.06 g (0.093 mmol) of PbCl2, 0.02 g (0.054 mmol) of PbBr2, 0.027 g (0.099 mmol) of ErCl3·6H2O, 0.053 g (0.136 mmol) of YbCl3·6H2O, 2 mL of OA, 2 mL of OAm and 10 mL of ODE was added to a 100 mL three-necked flask, heated and stirred under N2 protection until completely dissolved, heated to 150 ° C and kept warm for 1 h, then heated to 270 ° C, kept for 5 min, and 1 mL of perovskite precursor was quickly injected. After 10 seconds, the flask was immersed in an ice water bath, immediately cooled to room temperature, and then centrifuged (9500 r / min, 10 min), the supernatant was poured out, 3 mL of ethyl acetate and 3 mL of toluene were added to the precipitate, and after the precipitate was completely dissolved, centrifuged (9500 r / min, 10 min), the supernatant was poured out, and the precipitate was dissolved in 3 mL of toluene, and allowed to stand for stratification, and the supernatant was taken to obtain an erbium / ytterbium co-doped perovskite quantum dot solution;

[0062] (3) Dispersing diallyl thiosulfinate with a concentration of 99.5% (wt.) in toluene solvent, diluting to a 0.8 mg / mL diallyl thiosulfinate-toluene solution, taking 2 mL of the erbium / ytterbium co-doped perovskite quantum dot solution obtained in step (2) and adding 60 μL of the above diallyl thiosulfinate-toluene solution, and shaking vigorously for 5 minutes to prepare an erbium / ytterbium co-doped titanium ore near-infrared luminescent quantum dot solution; wherein the erbium / ytterbium co-doped titanium ore near-infrared luminescent quantum dot is of CsPbX3 type, and the transmission electron microscope image is shown in detail. Figure 1 ,from Figure 1 It can be seen that the quantum dots have a highly uniform size distribution.

[0063] (4) 85 μL of erbium / ytterbium co-doped perovskite near-infrared luminescent quantum dot solution was taken up with a pipette, evenly dropped on the substrate, and spin coated at a speed of 2000 r / min for 30 s to form a film, thereby preparing an erbium / ytterbium co-doped perovskite near-infrared luminescent quantum dot film. Figure 2 a) is a scanning electron microscope of the erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film prepared in Example 1, and b) is an atomic force microscope; Figure 2 It can be seen that the film formed by spin coating of quantum dots is continuous, dense, smooth and has low roughness.

[0064] Application Example 1

[0065] A thin strip electrode was etched on a transparent conductive glass substrate, and then a hole injection layer (PEDOT:PSS material with a thickness of 30 nm) and a hole transport layer (PVK material with a thickness of 40 nm) were spin-coated in sequence. Then, the erbium / ytterbium co-doped titanium ore near-infrared luminescent quantum dots (Er 3+ / Yb 3+ :CsPbCl 2.7 Br 0.3 The quantum dot film obtained by spin coating the solution is the perovskite light-emitting layer (the spin coating speed is 2000r / min, the spin coating time is 30s, and the thickness is 40nm); after completion, it is transferred to the organic evaporation chamber and wait until the vacuum degree is lower than 2*10 -4 Pa, evaporate the electron transport and hole blocking layer (using TPBi, thickness of 45nm), the evaporation rate is controlled at 0.05-0.08nm / s, and then evaporate the metal cathode layer in vacuum atmosphere (using a composite cathode composed of LiF and Ag, LiF thickness of 1nm, Ag thickness of 100nm), where the evaporation rate of lithium fluoride (LiF) is controlled at 0.02nm / s, and the evaporation rate of silver (Ag) is controlled at 0.2nm / s. The prepared light-emitting diode device is as follows Figure 3 shown.

[0066] A forward voltage is applied between the positive and negative electrodes of a light-emitting diode. Figure 4 This is the photoluminescence spectrum of Er-Yb co-doped perovskite near-infrared luminescent quantum dot film. Figure 4 It can be seen that the prepared quantum dot film emits near-infrared characteristic fluorescence of 986nm of ytterbium ions and 1540nm of erbium ions under 365nm ultraviolet light excitation. Figure 5 The electroluminescence spectrum of the light-emitting diode device prepared in Application Example 1; Figure 5 It can be seen that in addition to the characteristic emission peak of perovskite at 410nm, it also emits the characteristic emission peak of ytterbium ion with the main peak at 986nm and the characteristic emission peak of erbium ion at 1540nm. Figure 4 The photoluminescence spectrum of quantum dots is almost completely consistent with their electroluminescence spectrum.

[0067] Figure 6 The voltage-current density characteristic curve of the light-emitting diode prepared in Application Example 1 shows that the current density increases with the increase of voltage.

[0068] Figure 7 The voltage-power density characteristic curves of the light-emitting diode prepared in Application Example 1 at 986 nm (a) and 1540 nm (b). It can be seen that at the beginning of 986 nm, as the voltage gradually increases, the power density increases rapidly, gradually slows down at 4 V, and starts to slowly decrease at 6 V. At the beginning of 1540 nm, as the voltage gradually increases, the power density increases rapidly, gradually slows down at 3 V, and starts to slowly decrease at 6 V.

[0069] Figure 8The voltage-external quantum efficiency curves of the light-emitting diode prepared in Application Example 1 at 986nm (a) and 1540nm (b) respectively show that the maximum external quantum efficiency of the light-emitting diode device at 986nm reaches 8.7%, and the maximum external quantum efficiency at 1540nm reaches 1.2%, which is the most efficient perovskite-based ytterbium ion and erbium ion electroluminescence to date.

[0070] Comparative Example 1

[0071] (1) 0.2 g CsCO3 and 0.7 mL OA were added to 7 mL ODE, heated to 120 °C and stirred for 1 h under nitrogen protection to obtain a clear perovskite precursor;

[0072] (2) 0.06 g (0.093 mmol) PbCl2, 0.02 g (0.054 mmol) PbBr2, 0.027 g (0.099 mmol) ErCl3·6H2O, 0.053 g (0.136 mmol) YbCl3·6H2O, 2 mL OA, 2 mL OAm and 10 mL ODE were added to a 100 mL three-necked flask. The mixture was heated and stirred under N2 protection until completely dissolved. The mixture was heated to 150 °C and kept warm for 1 h. The temperature was then raised to 270 °C and maintained for 5 min. 1 mL of perovskite precursor was quickly injected. After 10 s, the flask was immersed in an ice water bath and immediately cooled to room temperature. The flask was then placed in a centrifuge (9500 r / min, 10 min). The supernatant was discarded and 3 mL of ethyl acetate and 3 mL of toluene were added to the precipitate. After the precipitate was completely dissolved. Centrifuge (9500r / min, 10min), pour off the supernatant, dissolve the precipitate in 3mL toluene, let stand for stratification, take the supernatant, and obtain the erbium / ytterbium co-doped perovskite quantum dot solution;

[0073] (3) 85 μL of erbium / ytterbium co-doped titanium ore near-infrared luminescent quantum dot solution was taken up with a pipette, evenly dropped on the substrate, and spin coated at a speed of 2000 r / min for 30 s to form a film, thereby preparing an erbium / ytterbium co-doped perovskite quantum dot film. Fig. 9 Transmission electron microscopy of the erbium / ytterbium co-doped perovskite quantum dots. Fig. 9 It can be seen that the perovskite quantum dots have irregular shapes and uneven size distribution. Figure 1 Compared with perovskite quantum dots, the order of arrangement of quantum dots is far less Figure 1 .

[0074] Application Example 2

[0075] The same as Application Example 1, except that the erbium / ytterbium co-doped titanium ore near-infrared luminescent quantum dot solution is replaced by the erbium / ytterbium co-doped perovskite quantum dot solution prepared in step (2) of Comparative Example 1.

[0076] The performance of the prepared light-emitting diodes was tested. Fig.10 This is the electroluminescence spectrum of the light-emitting diode device prepared in Application Example 2. Under a voltage of 5V, the near-infrared peak intensity of the light-emitting diode is low, indicating that the energy transfer efficiency is low.

[0077] Fig.11 The voltage-current density characteristic curve of the light-emitting diode prepared in Application Example 2 is compared with the light-emitting diode prepared in Application Example 1. It can be seen that the current density intensity is low. This is because the light-emitting layer film is uneven and the leakage current is large.

[0078] Fig.12 The voltage-power density characteristic curves at 986nm (a) and 1540nm (b) of the light-emitting diode prepared in Application Example 2. Compared with the light-emitting diode prepared in Application Example 1, the maximum power density of the light-emitting diode prepared in Application Example 2 at 986nm and 1540nm is only 0.52 times and 0.47 times that of the light-emitting diode prepared in Application Example 1, respectively.

[0079] Fig.13 The voltage-external quantum efficiency curves of the light-emitting diode prepared in Application Example 2 at 986nm (a) and 1540nm (b) respectively show that the maximum external quantum efficiency of the light-emitting diode device at 986nm is only 3.2%, and the maximum external quantum efficiency at 1540nm is 0.12%. Compared with the light-emitting diode prepared in Application Example 1, the maximum external quantum efficiency of the light-emitting diode prepared in Application Example 2 at 986nm and 1540nm is only 0.368 times and 0.1 times of that of the light-emitting diode prepared in Application Example 1, respectively.

[0080] The above are only preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for preparing an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film, characterized in that: A diallyl thiosulfinate organic solution and an erbium / ytterbium co-doped perovskite quantum dot solution are mixed to obtain an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot solution, and the erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot solution is spin-coated on a substrate to obtain the erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film.

2. The preparation method according to claim 1, characterized in that: The volume ratio of the diallyl thiosulfinate organic solution to the erbium / ytterbium co-doped perovskite quantum dot solution is 0.03:

1.

3. The preparation method according to claim 2, characterized in that: The concentration of the diallyl thiosulfinate organic solution is 0.8 mg / mL.

4. The preparation method according to claim 2, characterized in that: The preparation method of the erbium / ytterbium co-doped perovskite quantum dot solution comprises the following steps: in a nitrogen atmosphere, heating and stirring a mixed solution of cesium carbonate, oleic acid and octadecene until all dissolved, heating to 100-150° C. and stirring for 0.5-1h to obtain a perovskite precursor; in a nitrogen atmosphere, heating and stirring a mixed solution of lead chloride, lead bromide, erbium chloride hexahydrate, ytterbium chloride hexahydrate, oleic acid, oleyl ammonia and octadecene until completely dissolved, heating to 150° C. and keeping the temperature for 1h, then heating to 270° C. and keeping the temperature for 5min, rapidly injecting the perovskite precursor, cooling to room temperature, centrifuging, adding a mixed solution of ethyl acetate and toluene to the precipitate, centrifuging again after dissolution, dissolving the precipitate in toluene, standing for stratification, and taking the supernatant, which is the erbium / ytterbium co-doped perovskite quantum dot solution.

5. The preparation method according to claim 4, characterized in that: The usage ratio of cesium carbonate, oleic acid and octadecene is 0.2 g: 0.7 mL: 7 mL.

6. The preparation method according to claim 4, characterized in that: The dosage ratio of the lead chloride, lead bromide, erbium chloride hexahydrate, ytterbium chloride hexahydrate, oleic acid, oleylamine, octadecene and perovskite precursor is 0.06g: 0.02g: 0.027g: 0.053g: 2mL: 2mL: 10mL: 1mL.

7. A preparation method according to any one of claims 1 to 6 for preparing an erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film.

8. Use of the erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film according to claim 7 in the preparation of electronic components.

9. A light-emitting diode comprising the erbium-ytterbium co-doped perovskite near-infrared luminescent quantum dot film according to claim 7, characterized in that: From bottom to top, it includes a transparent conductive glass substrate, a hole injection layer, a hole transport layer, a perovskite light-emitting layer, an electron transport and hole blocking layer, a buffer layer and a metal cathode layer; the perovskite light-emitting layer is an erbium-ytterbium co-doped perovskite near-infrared light-emitting quantum dot film layer.

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