Preparation method of novel perovskite light-emitting diode

Abstract

The invention discloses a preparation method of a novel perovskite light-emitting diode, and the method specifically comprises the following steps: carrying out the ultrasonic cleaning of a glass substrate with an indium tin oxide / fluorine-doped tin oxide coating, and enabling the glass substrate to serve as an anode; the cleaned substrate is treated to enable the surface to be hydrophilic, then the Me-4PACz solution is smeared on the substrate, and the Me-4PACz film is spin-coated with the PVK solution; the substrate is transferred to a nitrogen charging glove box, the Me-4PACz / PVK thin film is spin-coated with a perovskite precursor solution, the perovskite precursor solution is prepared by dissolving quantitative CsBr, PbBr2 and an additive AX into DMSO to form the perovskite solution, A can be any one of Cs < + >, GA < + >, FA < + >, Li < + >, Na < + >, K < + > and Rb < + >, and X represents halogen ions; the cathode and the anode of the substrate are scraped out, and the substrate is transferred to a thermal evaporation mask baffle and placed into a thermal evaporation coating instrument. According to the invention, a small amount of additive is added into the inorganic perovskite solution, so that the external quantum efficiency and the luminescence life of perovskite are improved.

Description

Technical Field

[0001] The invention relates to the technical field of light-emitting diodes, and in particular to a method for preparing a novel perovskite light-emitting diode. Background Art

[0002] In recent years, with the rise of new semiconductor devices such as photovoltaic cells, light-emitting diodes, and detectors, perovskites have continued to develop. As an emerging semiconductor material, metal halide perovskites have great advantages in luminescence, such as high carrier mobility, adjustable band gap, high fluorescence yield, long carrier diffusion length, and low defect density, and have received great attention. Perovskite light-emitting diodes have received a lot of attention due to their excellent performance, but the luminescence lifetime of perovskite light-emitting diodes needs to be improved. Summary of the invention

[0003] The purpose of the present invention is to provide a novel method for preparing a perovskite light-emitting diode to solve the problems mentioned in the background technology. To achieve the above purpose, the present invention provides the following technical solution: a novel method for preparing a perovskite light-emitting diode, specifically comprising the following contents:

[0004] (1) The glass substrate coated with indium tin oxide / fluorine-doped tin oxide was ultrasonically cleaned with detergent, distilled water, acetone and ethanol in sequence and used as an anode; the cleaned substrate was treated with ultraviolet ozone for 15 minutes to make the surface hydrophilic, and then the Me-4PACz solution was applied on the substrate and annealed at 100°C in a nitrogen environment for 10 minutes. After the annealing was completed, the PVK solution was spin-coated on the Me-4PACz film and annealed at 120°C in a nitrogen environment for 20 minutes to form a hole transport layer;

[0005] (2) The substrate was transferred to a nitrogen-filled glove box, and a perovskite precursor solution was spin-coated onto the Me-4PACz / PVK film, followed by annealing on a heating table at 100°C for 10 min. The perovskite precursor solution was prepared by dissolving a certain amount of CsBr, PbBr2, and an additive AX in DMSO to form a perovskite solution, wherein A can be Cs + , GA + , FA + , Li + 、Na + , K + and Rb + Any one of the following, X represents a halogen ion, Pb 2+ The concentration is 0.2M;

[0006] (3) Scrape out the cathode and anode of the substrate, transfer the substrate to a thermal evaporation mask baffle, and place it in a thermal evaporation coating apparatus; deposit TPBi, lithium fluoride, and a metal layer by thermal evaporation coating to complete the preparation of PeLED.

[0007] Preferably, the specific method of applying the Me-4PACz solution on the substrate in (1) is: spin coating the Me-4PACz solution at 3000 rpm for 40 seconds.

[0008] Preferably, the spin coating method in (2) is: spin coating at 4000 rpm for 2 min.

[0009] Preferably, in (3), the thickness of TPBi is 40 nm, the thickness of lithium fluoride is 1 nm, and the thickness of the metal layer is 100 nm.

[0010] Preferably, the metal layer is Al, Ag or Au.

[0011] Preferably, the cesium excess in the perovskite precursor solution is 10% or 20%.

[0012] Technical effects and advantages of the present invention: The present invention improves the external quantum efficiency and luminescence lifetime of perovskite by adding a small amount of additives to the inorganic perovskite solution, which not only improves the performance of the device but also helps to improve its long-term stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 is the IV diagram of the perovskite light-emitting diode;

[0014] Figure 2 This is the external quantum efficiency diagram of perovskite light-emitting diodes;

[0015] Figure 3 50mA / cm for perovskite light-emitting diodes 2 Luminescence lifetime diagram. DETAILED DESCRIPTION

[0016] In order to make the technical means for realizing the present invention, the creative features, the objectives and effects to be achieved easy to understand, the present invention is further explained below in conjunction with specific diagrams. In the description of the present invention, it should be noted that, unless otherwise clearly stipulated and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, an integral connection or a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal connection of two components.

[0017] Example 1

[0018] A method for preparing a novel perovskite light-emitting diode, wherein the specific steps of the preparation are:

[0019] Step 1: The indium tin oxide (ITO) coated glass substrate was ultrasonically cleaned with detergent, distilled water, acetone and ethanol for 15 minutes and used as an anode. The cleaned substrate was treated with ultraviolet ozone for 15 minutes to make the surface hydrophilic, and then the Me-4PACz solution was applied on the substrate and annealed at 100°C in a nitrogen environment for 10 minutes. After the annealing was completed, the PVK solution was spin-coated on the Me-4PACz film and annealed at 120°C in a nitrogen environment for 20 minutes.

[0020] Step 2: After that, the substrate is transferred to a nitrogen-filled glove box, and a certain amount of CsBr and PbBr2 are dissolved in DMSO to form Pb 2+ The concentration of perovskite solution is 0.2M. 2+ The perovskite solution (concentration) was spin-coated onto the Me-4PACz / PVK film at 4000 rpm for 2 min, and then annealed on a heating stage at 100°C for 10 min.

[0021] Step 3: scrape out the cathode and anode of the substrate, transfer the substrate to the thermal evaporation mask baffle, and put it into the thermal evaporation coating instrument. The perovskite light-emitting diode (PeLED) is prepared by depositing TPBi (40nm), lithium fluoride (1nm), and aluminum (100nm) by thermal evaporation coating.

[0022] Example 2

[0023] A method for preparing a novel perovskite light-emitting diode, wherein the specific steps of the preparation are:

[0024] Step 1: The glass substrate coated with fluorine-doped tin oxide (FTO) was ultrasonically cleaned with detergent, distilled water, acetone and ethanol for 15 minutes and used as an anode. The cleaned substrate was treated with ultraviolet ozone for 15 minutes to make the surface hydrophilic, and then the Me-4PACz solution was applied on the substrate and annealed at 100°C in a nitrogen environment for 10 minutes. After the annealing was completed, the PVK solution was spin-coated on the Me-4PACz film and annealed at 120°C in a nitrogen environment for 20 minutes.

[0025] Step 2: After that, the substrate is transferred to a nitrogen-filled glove box, and a certain amount of CsBr and PbBr2 are dissolved in DMSO to form Pb 2+ The concentration of perovskite solution was 0.3M, and 5% GABr was added. 2+ The perovskite solution (concentration) was spin-coated onto the Me-4PACz / PVK film at 4000 rpm for 2 min, and then annealed on a heating stage at 100°C for 10 min.

[0026] Step 3: scrape out the cathode and anode of the substrate, transfer the substrate to the thermal evaporation mask baffle, and put it into the thermal evaporation coating instrument. The perovskite light-emitting diode (PeLED) is prepared by depositing TPBi (40nm), lithium fluoride (1nm), and gold (100nm) by thermal evaporation coating.

[0027] Example 3

[0028] A method for preparing a novel perovskite light-emitting diode, wherein the specific steps of the preparation are:

[0029] Step 1: The glass substrate coated with fluorine-doped tin oxide (FTO) was ultrasonically cleaned with detergent, distilled water, acetone and ethanol for 15 minutes and used as an anode. The cleaned substrate was treated with oxygen plasma for 5 minutes to make the surface hydrophilic, and then the Me-4PACz solution was applied on the substrate and annealed at 100°C in a nitrogen environment for 10 minutes. After the annealing was completed, the PVK solution was spin-coated on the Me-4PACz film and annealed at 120°C in a nitrogen environment for 20 minutes.

[0030] Step 2: After that, the substrate is transferred to a nitrogen-filled glove box, and a certain amount of CsBr and PbBr2 are dissolved in DMSO to form Pb 2+ The concentration was 0.3M, and then 10% GABr was added. 2+ The perovskite solution (concentration) was spin-coated onto the Me-4PACz / PVK film at 4000 rpm for 2 min, and then annealed on a heating stage at 100°C for 10 min.

[0031] Step 3: scrape out the cathode and anode of the substrate, transfer the substrate to the thermal evaporation mask baffle, and put it into the thermal evaporation coating instrument. The perovskite light-emitting diode (PeLED) is prepared by depositing TPBi (40nm), lithium fluoride (1nm), and silver (100nm) by thermal evaporation coating.

[0032] Example 4

[0033] A method for preparing a novel perovskite light-emitting diode, wherein the specific steps of the preparation are:

[0034] Step 1, the indium tin oxide (ITO) coated glass substrate was ultrasonically cleaned with detergent, distilled water, acetone and ethanol for 15 minutes in sequence and used as an anode. The cleaned substrate was treated with oxygen plasma for 5 minutes to make the surface hydrophilic, and the substrate was transferred to a glove box filled with nitrogen. Me-4PACz was dissolved in anhydrous ethanol at a concentration of 1 mg / mL. The Me-4PACz solution was dropped onto the glass substrate, spin-coated at 3000 rpm for 40 seconds, and annealed at 100°C in a nitrogen environment for 10 minutes. PVK was dissolved in chlorobenzene at a concentration of 3 mg / mL. The PVK solution was dropped onto the substrate spun with Me-4PACz, spin-coated at 3000 rpm for 40 seconds, and annealed at 120°C in a nitrogen environment for 20 minutes.

[0035] Step 2: Dissolve the quantitative CsBr and PbBr2 in DMSO to form Pb 2+ The concentration was 0.2M, and 5% CsF was added. 2+ The perovskite solution (concentration) was spin-coated onto the Me-4PACz / PVK film at 4000 rpm for 2 min, and then annealed on a heating stage at 100°C for 10 min.

[0036] Step 3: scrape out the cathode and anode of the substrate, transfer the substrate to the thermal evaporation mask baffle, and put it into the thermal evaporation coating instrument. The perovskite light-emitting diode (PeLED) is prepared by depositing TPBi (40nm), lithium fluoride (1nm), and aluminum (100nm) by thermal evaporation coating.

[0037] Example 5

[0038] A method for preparing a novel perovskite light-emitting diode, wherein the specific steps of the preparation are:

[0039] Step 1, ultrasonically clean the indium tin oxide (ITO) coated glass substrate with detergent, distilled water, acetone and ethanol for 15 minutes in sequence and use it as an anode. The cleaned substrate is treated with oxygen plasma for 5 minutes to make the surface hydrophilic, and the substrate is transferred to a glove box filled with nitrogen. Me-4PACz is dissolved in anhydrous ethanol at a concentration of 3 mg / mL. The Me-4PACz solution is dropped onto the glass substrate, spin-coated at 3000 rpm for 40 seconds, and annealed at 100°C in a nitrogen environment for 10 minutes. PVK is dissolved in chlorobenzene at a concentration of 3 mg / mL. The PVK solution is dropped onto the substrate spun with Me-4PACz, spin-coated at 2000 rpm for 40 seconds, and annealed at 120°C in a nitrogen environment for 20 minutes.

[0040] Step 2: Dissolve the quantitative CsBr and PbBr2 in DMSO to form Pb 2+The concentration was 0.2M, and then 5% GABr solution was added. 2+ The perovskite solution (concentration) was spin-coated onto the Me-4PACz / PVK film at 4000 rpm for 2 min, and then annealed on a heating stage at 100°C for 10 min.

[0041] Step 3: scrape out the cathode and anode of the substrate, transfer the substrate to the thermal evaporation mask baffle, and put it into the thermal evaporation coating instrument. The perovskite light-emitting diode (PeLED) is prepared by depositing TPBi (25nm), lithium fluoride (1nm), and aluminum (100nm) by thermal evaporation coating.

[0042] Example 6

[0043] A method for preparing a novel perovskite light-emitting diode, wherein the specific steps of the preparation are:

[0044] Step 1, the glass substrate coated with fluorine-doped tin oxide (FTO) was ultrasonically cleaned with detergent, distilled water, acetone and ethanol for 15 minutes in sequence and used as an anode. The cleaned substrate was treated with oxygen plasma for 5 minutes to make the surface hydrophilic, and the substrate was transferred to a glove box filled with nitrogen. Me-4PACz was dissolved in anhydrous ethanol at a concentration of 1 mg / mL. The Me-4PACz solution was dropped onto the glass substrate, spin-coated at 3000 rpm for 40 seconds, and annealed at 100°C in a nitrogen environment for 10 minutes. PVK was dissolved in chlorobenzene at a concentration of 3 mg / mL. The PVK solution was dropped onto the substrate spun with Me-4PACz, spin-coated at 3000 rpm for 40 seconds, and annealed at 120°C in a nitrogen environment for 20 minutes.

[0045] Step 2: Dissolve the quantitative CsBr and PbBr2 in DMSO to form Pb 2+ The concentration was 0.2M, and 10% CsF was added. 2+ The perovskite solution (concentration) was spin-coated onto the Me-4PACz / PVK film at 4000 rpm for 2 min, and then annealed on a heating stage at 100°C for 10 min.

[0046] Step 3: scrape out the cathode and anode of the substrate, transfer the substrate to the thermal evaporation mask baffle, and put it into the thermal evaporation coating instrument. The perovskite light-emitting diode (PeLED) is prepared by depositing TPBi (40nm), lithium fluoride (1nm), and aluminum (100nm) by thermal evaporation coating.

[0047] The performance of the perovskite light-emitting diodes obtained in Examples 1-6 was compared. The performance of Example 6 was significantly improved, and the perovskite device obtained in Example 6 obtained IV graphs, external quantum efficiency graphs and 50 mA / cm 2The luminescence lifetime diagrams are as follows: Figure 1 , Figure 2 and Figure 3 As shown, it can be seen that by adding a small amount of additive AX to the inorganic perovskite solution, the external quantum efficiency and luminescence lifetime of the perovskite are improved.

[0048] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for preparing a novel perovskite light-emitting diode, characterized in that: Specifically include the following: (1) The glass substrate coated with indium tin oxide / fluorine-doped tin oxide was ultrasonically cleaned with detergent, distilled water, acetone and ethanol in sequence and used as an anode; the cleaned substrate was treated with ultraviolet ozone for 15 minutes to make the surface hydrophilic, and then the Me-4PACz solution was applied on the substrate and annealed at 100°C in a nitrogen environment for 10 minutes. After the annealing was completed, the PVK solution was spin-coated on the Me-4PACz film and annealed at 120°C in a nitrogen environment for 20 minutes to form a hole transport layer; (2) The substrate was transferred to a nitrogen-filled glove box, and a perovskite precursor solution was spin-coated onto the Me-4PACz / PVK film, followed by annealing on a heating table at 100°C for 10 min, wherein the perovskite precursor solution was prepared by dissolving a certain amount of CsBr, PbBr2, and an additive AX in DMSO to form a perovskite solution, wherein A can be any one of Cs+, GA+, FA+, Li+, Na+, K+, and Rb+, and X represents a halogen ion, and the concentration of Pb2+ is 0.2 M; (3) Scrape out the cathode and anode of the substrate, transfer the substrate to the thermal evaporation mask baffle, and place it in the thermal evaporation coating instrument; TPBi, lithium fluoride and metal layers are deposited by thermal evaporation coating to complete the preparation of PeLED.

2. The method for preparing a novel perovskite light-emitting diode according to claim 1, characterized in that: The specific method for applying the Me-4PACz solution on the substrate in (1) is: spin coating the Me-4PACz solution at 3000 rpm for 40 seconds.

3. The method for preparing a novel perovskite light-emitting diode according to claim 1, characterized in that: The spin coating method in (2) is: spin coating at 4000 rpm for 2 minutes.

4. The method for preparing a novel perovskite light-emitting diode according to claim 1, characterized in that: In (3), the thickness of TPBi is 40 nm, the thickness of lithium fluoride is 1 nm, and the thickness of the metal layer is 100 nm.

5. The method for preparing a novel perovskite light-emitting diode according to claim 4, characterized in that: The metal layer is Al, Ag, or Au.

6. The method for preparing a novel perovskite light-emitting diode according to claim 1, characterized in that: The cesium excess in the perovskite precursor solution is 10% or 20%.

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