Perovskite light-emitting diode and preparation method thereof

Abstract

The application relates to the technical field of light-emitting diodes, in particular to a blue light perovskite light-emitting diode, which comprises a perovskite light-emitting layer, the perovskite light-emitting layer comprises a perovskite, a large-group organic halide and a halogenated organic halide, wherein the large-group organic halide comprises an organic chloroamine LCl or an organic bromoamine LBr, L is a positive monovalent organic amine ion with an ionic radius greater than 300 picometers; the halogenated organic halide comprises a halogenated organic chloroamine MCl or a halogenated organic bromoamine MBr, wherein M is a positive monovalent organic amine ion containing a carbon halogen bond (C-F / C-Cl / C-Br), which can improve the light-emitting efficiency of the blue light perovskite light-emitting diode and ensure stable emission of blue light.

Description

Technical Field

[0001] This application belongs to the field of light-emitting diode technology, specifically a blue perovskite light-emitting diode and its fabrication method. Background Technology

[0002] Lead halide perovskites, as a popular semiconductor material, have wide applications in optoelectronics, such as photovoltaic cells, light-emitting diodes (LEDs), lasers, and detectors. They possess outstanding optical and electrical properties, including high photoluminescence quantum efficiency (PLQY), tunable bandgap, high carrier mobility, and high color purity, as well as solution processability. These characteristics make them promising candidates for high-performance, cost-effective optoelectronic devices, and they are expected to compete with OLEDs and QLEDs, which are also surface light sources, in the display and lighting fields. Therefore, perovskite-type electroluminescent diodes (PeLEDs) have become an important research area.

[0003] However, compared to green, red, and near-infrared devices, although the EQE of blue light-emitting diodes (PeLEDs) has exceeded 10%, blue PeLEDs still suffer from problems such as spectral instability and uncontrollable phase formation and distribution, resulting in relatively low efficiency. As a key component in displays and lighting, the performance of blue PeLEDs still needs further improvement. Therefore, ensuring stable blue light emission from perovskites and improving the luminous efficiency of blue perovskite LEDs has become an urgent problem to be solved. Summary of the Invention

[0004] The purpose of one or more embodiments in this specification is to provide a blue perovskite light-emitting diode and a method for fabricating the same, which can ensure stable blue light emission from the perovskite and improve the luminous efficiency of the blue perovskite light-emitting diode.

[0005] To solve the above-mentioned technical problems, one or more embodiments of this specification are implemented as follows:

[0006] In a first aspect, a blue perovskite light-emitting diode is provided, comprising a perovskite light-emitting layer, wherein the perovskite light-emitting layer comprises perovskite, a large-group organic halide, and a halogenated organic halide, wherein the large-group organic halide comprises an organochlorine LCl or an organobromine LBr, where L is a monovalent organic amine ion with an ionic radius greater than 300 picometers; and the halogenated organic halide comprises a halogenated organochlorine MCl or a halogenated organobromine MBr, where M is a monovalent organic amine ion containing a carbon-halogen bond (CF / C-Cl / C-Br).

[0007] Secondly, a method for preparing a blue perovskite light-emitting diode is proposed, comprising the following steps: preparing a perovskite precursor solution; growing a perovskite light-emitting layer; wherein the precursor solution includes perovskite, a large-group organic halide, and a halogenated organic halide, wherein the large-group organic halide includes an organochlorine LCl or an organobromine LBr, where L is a monovalent organic amine ion with an ionic radius greater than 300 picometers; and the halogenated organic halide includes a halogenated organochlorine MCl or a halogenated organobromine MBr, where M is a monovalent organic amine ion containing a carbon-halogen bond (CF / C-Cl / C-Br).

[0008] As can be seen from the technical solutions provided in one or more embodiments of this specification, the blue perovskite light-emitting diode provided in this invention simultaneously introduces large-group organic halides and halogenated organic halides into the perovskite system to prepare a blue quasi-two-dimensional perovskite. The combined action of the large-group organic halide amines and halogenated organic halide amines causes the perovskite to form a quasi-two-dimensional n-phase structure, thereby controlling the generation and distribution of the quasi-two-dimensional phase and achieving adjustment of the dimensional structure and band gap width of the perovskite. Furthermore, the interaction between the carbon-halogen bonds and amino bonds in the halogenated organic halides and the halide ions in the perovskite increases the exciton binding energy of the blue perovskite, improves the band gap width, suppresses the formation of the two-dimensional phase (n=1), and reduces the generation of the quasi-two-dimensional high-n phase (n≥4), allowing excitons to effectively transfer from the n=2 phase to the n=3 phase, thus improving the luminous efficiency of the quasi-two-dimensional perovskite while maintaining stable blue light emission. This invention addresses the problems of spectral instability and uncontrollable phase formation and distribution in existing blue perovskite light-emitting diodes, ensuring stable blue light emission from perovskite and improving the luminous efficiency of blue perovskite light-emitting diodes. Attached Figure Description

[0009] To more clearly illustrate the technical solutions in one or more embodiments or prior art of this specification, the accompanying drawings used in the description of one or more embodiments or prior art will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments recorded in this specification. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0010] Figure 1 This is a schematic diagram of the structure of a blue perovskite light-emitting diode provided according to the present invention;

[0011] Figure 2 These are the ultraviolet-visible absorption spectra of the perovskite luminescent layer in Comparative Example 1 and Example 1 provided by the present invention;

[0012] Figure 3 These are the photoluminescence spectra of the perovskite luminescent layer in Comparative Example 1 and Example 1 provided by the present invention;

[0013] Figure 4 These are the current density-voltage-brightness curves of the blue perovskite light-emitting diodes in Comparative Example 1 (Curve 1) and Example 1 (Curve 2) provided by the present invention.

[0014] Figure 5 These are the external quantum efficiency-current density curves of the blue perovskite light-emitting diodes in Comparative Example 1 (Curve 1) and Example 1 (Curve 2) provided by the present invention.

[0015] Figure 6 This is the electroluminescence spectrum of the blue perovskite light-emitting diode under different bias voltages in Comparative Example 1 provided by the present invention.

[0016] Figure 7 This is the electroluminescence spectrum of the blue perovskite light-emitting diode under different bias voltages in Embodiment 1 provided by the present invention.

[0017] Reference numerals: 1. Substrate; 2. Anode layer; 3. Anode interface layer; 4. Perovskite light-emitting layer; 5. Cathode interface layer; 6. Cathode interface modification layer; 7. Cathode layer. Detailed Implementation

[0018] To enable those skilled in the art to better understand the technical solutions in this specification, the technical solutions in one or more embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described one or more embodiments are merely some embodiments of this specification, and not all embodiments. All other embodiments obtained by those skilled in the art based on one or more embodiments of this specification without creative effort should fall within the protection scope of this document.

[0019] The blue perovskite light-emitting diode provided in this invention ensures stable blue light emission from the perovskite and improves the luminous efficiency of the blue perovskite light-emitting diode. The blue perovskite light-emitting diode and its various components provided in this specification will be described in detail below.

[0020] Example 1

[0021] Reference Figure 1As shown, the blue perovskite light-emitting diode provided in this embodiment of the invention includes a perovskite light-emitting layer 4. The perovskite light-emitting layer 4 includes perovskite, a large-group organic halide, and a halogenated organic halide. The large-group organic halide includes organochlorine LCl or organobromine LBr, where L is a monovalent organic amine ion with an ionic radius greater than 300 picometers. The halogenated organic halide includes halogenated organochlorine MCl or halogenated organobromine MBr, where M is an organic amine ion containing a carbon-halogen bond (CF / C-Cl / C-Br) and a monovalent ionic value.

[0022] The perovskite luminescent layer is spin-coated from a perovskite precursor solution. The precursor includes perovskite and doped macro-organohalides and halogenated organohalides. The macro-organohalides are organochlorines (LCl) or organobromines (LBr), where L is a monovalent organic amine ion with an ionic radius greater than 300 picometers. The halogenated organohalides are halogenated organochlorines (MCl) or halogenated organobromines (MBr), where M is a monovalent organic amine ion containing a carbon-halogen bond (CF / C-Cl / C-Br).

[0023] The implementation principle of the blue perovskite light-emitting diode provided in this invention is as follows: A blue quasi-two-dimensional perovskite is prepared by simultaneously introducing large-group organic halides and halogenated organic halides into the perovskite system. The large-group organic halides induce a quasi-two-dimensional structure in the perovskite. By adjusting the stoichiometric ratio of the large-group halogenated amines to the perovskite, the dimensional structure and band gap width of the perovskite are controlled. Furthermore, the strong interaction between the halogens of the carbon-halogen bonds in the halogenated organic halides and the halide ions in the perovskite structure strongly restricts halide ion migration, improving blue light emission stability. It also suppresses the formation of two-dimensional phases and reduces the generation of high-n phases in the quasi-two-dimensional perovskite, achieving band gap broadening. This, in turn, improves the stable blue light emission and high luminous efficiency of the blue quasi-two-dimensional PeLEDs.

[0024] Compared to existing technologies, this invention uses both large-group organic halides and halogenated organic halides as organic spacers to induce the generation of high-quality, high-purity quasi-two-dimensional phases. The strong interaction between the halogen in the carbon-halogen bond of the halogenated organic halide and the halide ions in the perovskite structure can not only strongly restrict the migration of halide ions and improve the stability of blue light emission, but also allow the carbon-halogen bond of the halogenated organic halide to precisely control the quasi-two-dimensional phase growth together with organic amine ions, thereby achieving stable blue light emission and high luminous efficiency of blue quasi-two-dimensional PeLEDs.

[0025] Preferably, in the blue perovskite light-emitting diode provided in this embodiment of the invention, the halogenated organic ammonium chloride MCl is a halogenated alkyl ammonium chloride or a halogenated aryl ammonium chloride, and the halogenated organic bromide MBr is a halogenated alkyl ammonium bromide or a halogenated aryl ammonium bromide, wherein the halogenated alkyl ammonium chloride is XC. n H 2n NH3Cl, where the alkyl group has 2-5 carbon atoms (n) and X is a halogen; haloarylamine chlorides are X-Ph-C. n H 2n -NH3Cl, Ph is phenylene, carbon number n is 1-5, X is a halogen; haloalkylamine bromide is XC n H 2n NH3Br, with carbon number n ranging from 1 to 5, and X being a halogen; haloaryl bromides are represented by X-Ph-C. n H 2n -NH3Br, Ph is phenylene, n is 1-5 carbons, and X is a halogen.

[0026] The large-group organic halide is an organochlorinated amine LCl or an organobrominated amine LBr, where L is a monovalent organic amine ion with an ionic radius greater than 300 picometers, such as one or more of propylamine chloride, phenethylamine hydrochloride, propylamine bromide, butylamine bromide, and phenethylamine hydrobromide.

[0027] Halogenated organohalides are halogenated organochlorinated amines MCl or halogenated organobromines MBr, where M is a monovalent organic amine ion containing a carbon-halogen bond (CF / C-Cl / C-Br). Halogenated organochlorinated amines and halogenated organobromines are halogenated alkylamine chlorides, halogenated arylamine chlorides, halogenated alkylbromines, and halogenated arylbromines. Halogenated alkylammonium chlorides are XC. n H 2n NH3Cl, where the alkyl group has 2-5 carbon atoms (n) and X is a halogen; such as one or more of 2-fluoroethylamine hydrochloride, 2-chloroethylamine hydrochloride, 2-bromoethylamine hydrochloride, and 3-chloropropylamine hydrochloride. The halogenated arylamine chloride is X-Ph-C. n H 2n -NH3Cl, Ph is phenylene, n is 1-5 carbons, and X is a halogen; such as one or more of o-fluorophenylethylamine hydrochloride, p-fluorophenylethylamine hydrochloride, o-chloroaniline hydrochloride, 4-bromophenylhydrazine hydrochloride, and 3-bromobenzylamine hydrochloride. Halogenated alkyl bromides are XC. n H 2n NH3Br, with 1-5 carbon atoms (n), and X being a halogen, such as one or more of 3-fluoropropylamine hydrobromide, 4-chlorobutylamine hydrobromide, 2-bromoethylamine hydrobromide, and 3-bromopropylamine hydrobromide. The halogenated arylamine bromide is X-Ph-C. n H 2n-NH3Br, Ph is a phenylene oxide, the number of carbon atoms n is 1-5, and X is a halogen; such as one or more of p-fluorophenylethylamine hydrobromide, o-chlorobenzylamine hydrobromide, and p-bromobenzylamine hydrobromide.

[0028] Preferably, the blue perovskite light-emitting diode provided in this embodiment of the invention is composed of perovskite made of any one or a mixture of two of the following materials: cesium bromide or cesium chloride, and lead bromide or lead chloride. Further, in the blue perovskite light-emitting diode provided in this embodiment of the invention, the molar ratio of the large-group organic halide to lead ions is (0.2-1):1, and the molar ratio of the halogenated organic halide to lead ions is (0-1):1.

[0029] The perovskite luminescent layer 4 consists of perovskite and doped with large-group organic halides and halogenated organic halides. The perovskite is composed of any one or a mixture of two of the following materials: cesium bromide or cesium chloride, and lead bromide or lead chloride. These two types of materials are classified as cesium halide salts and lead halide salts based on whether they contain cesium or lead. The concentration of cesium bromide or cesium chloride is 0.1-0.3 mmol, the concentration of lead bromide or lead chloride is 0.1-0.3 mmol, the molar ratio of large-group organic halides to lead ions is (0.2-1):1, and the molar ratio of halogenated organic halides to lead ions is (0-1):1.

[0030] Preferably, in the blue perovskite light-emitting diode provided in the embodiments of the present invention, the perovskite light-emitting layer 4 has an anode interface layer 3 and a cathode interface layer 5 on both sides, respectively. The anode interface layer 3 is a polythiophene derivative poly(3,4-vinyldioxythiophene) doped polystyrene sulfonic acid, and the thickness of the anode interface layer 3 can be 10-50 nm.

[0031] Preferably, the blue perovskite light-emitting diode provided in this embodiment of the invention further includes a cathode interface modification layer 6 and a cathode layer 7 sequentially disposed on the cathode interface layer 5. The cathode interface modification layer 6 is lithium fluoride, and / or the cathode layer 7 is aluminum or silver. The cathode interface layer 5 can be TPBi, and its thickness can be 5-50 nm. The cathode interface modification layer 6 can be lithium fluoride, and its thickness can be 0.5-3 nm. Further, the cathode layer 7 can be aluminum or silver, and its thickness can be 20-150 nm.

[0032] Correspondingly, the anode layer 2 is indium tin oxide, and the anode layer 2 is a patterned transparent anode layer with a thickness of 50-200 nm.

[0033] like Figure 1 As shown, the blue perovskite light-emitting diode provided in this embodiment of the invention includes a patterned transparent anode layer 2, an anode interface layer 3, a perovskite light-emitting layer 4, a cathode interface layer 5, a cathode interface modification layer 6, and a cathode layer 7 sequentially formed on a substrate 1.

[0034] The above analysis shows that the blue perovskite light-emitting diode provided in this invention simultaneously introduces large-group organic halides and halogenated organic halides into the perovskite system to prepare a blue quasi-two-dimensional perovskite. The combined action of the large-group organic halide amines and halogenated organic halide amines enables the perovskite to form a quasi-two-dimensional n-phase structure, thereby controlling the generation and distribution of the quasi-two-dimensional phase and achieving adjustment of the perovskite's dimensional structure and band gap width. Furthermore, the interaction between the carbon-halogen bonds and amino bonds in the halogenated organic halides and the halide ions in the perovskite increases the exciton binding energy of the blue perovskite, improves the band gap width, suppresses the formation of the two-dimensional phase (n=1), and reduces the generation of the quasi-two-dimensional high-n phase (n≥4), allowing excitons to effectively transfer from the n=2 phase to the n=3 phase. This maintains stable blue light emission while improving the luminous efficiency of the quasi-two-dimensional perovskite. This invention addresses the problems of spectral instability and uncontrollable phase formation and distribution in existing blue perovskite light-emitting diodes, ensuring stable blue light emission from perovskite and improving the luminous efficiency of blue perovskite light-emitting diodes.

[0035] Example 2

[0036] The method for preparing a blue perovskite light-emitting diode provided in this embodiment includes the following steps: Step S10: Preparing a perovskite precursor solution, wherein the precursor solution includes perovskite, a large-group organic halide, and a halogenated organic halide. The large-group organic halide includes organochlorine LCl or organobromine LBr, where L is a monovalent organic amine ion with an ionic radius greater than 300 picometers; the halogenated organic halide includes halogenated organochlorine MCl or halogenated organobromine MBr, where M is an organic amine ion containing a carbon-halogen bond (CF / C-Cl / C-Br) and a monovalent ionic value.

[0037] Step S20: Growth of the perovskite luminescent layer. This embodiment of the invention utilizes the combined action of large-group organic halide amines and halogenated organic halide amines to regulate the generation and distribution of the quasi-two-dimensional phase. The interaction between carbon-halogen bonds and amino bonds and halide ions in the perovskite increases the exciton binding energy of the blue-light perovskite, improves the perovskite bandgap width, suppresses the formation of the two-dimensional phase (n=1), and simultaneously reduces the generation of the quasi-two-dimensional high-n phase (n≥4), allowing excitons to effectively transfer from the n=2 phase to the n=3 phase, maintaining stable blue light emission and improving the luminescence efficiency of the quasi-two-dimensional perovskite.

[0038] This invention introduces both large-group organic halides and halogenated organic halides into a perovskite system to prepare blue-light quasi-two-dimensional perovskites. The large-group organic halides induce a quasi-two-dimensional structure in the perovskite. By adjusting the stoichiometric ratio of the large-group organic halide to the perovskite, the dimensional structure and band gap of the perovskite can be controlled. The strong interaction between the halogens in the carbon-halogen bonds of the halogenated organic halides and the halide ions in the perovskite structure effectively restricts halide ion migration, enhancing blue light emission stability. It also suppresses the formation of two-dimensional phases in the quasi-two-dimensional perovskite and reduces the formation of high-n phases, thus broadening the band gap. This results in stable blue light emission and high-efficiency luminescence performance of blue-light quasi-two-dimensional PeLEDs.

[0039] Compared to existing technologies, this invention uses large-group organic halides and halogenated organic halides as organic spacers to induce the generation of high-quality, high-purity quasi-two-dimensional phases. The strong interaction between the halogens in the carbon-halogen bonds of the halogenated organic halides and the halide ions in the perovskite structure can not only achieve a strong confinement effect on the migration of halide ions to improve the stability of blue light emission, but also precisely control the quasi-two-dimensional phase growth together with organic amine ions, thereby achieving stable blue light emission and high-efficiency luminescence performance of blue quasi-two-dimensional PeLEDs.

[0040] Large-group organohalides are organochlorinated amines (LCl) or organobrominated amines (LBr), where L is a monovalent organic amine ion with an ionic radius greater than 300 picometers, such as propylamine chloride, phenethylamine hydrochloride, propylamine bromide, butylamine bromide, or phenethylamine hydrobromide. Halogenated organohalides are halogenated organochlorinated amines (MCl) or halogenated organobrominated amines (MBr), where M is a monovalent organic amine ion containing a carbon-halogen bond (CF / C-Cl / C-Br). Halogenated organochlorinated amines and halogenated organobrominated amines are halogenated alkylamine chlorides, halogenated arylamine chlorides, halogenated alkylamine bromides, and halogenated arylamine bromides. Halogenated alkylammonium chlorides are XC... n H 2n NH3Cl, where the alkyl group has 2-5 carbon atoms (n) and X is a halogen; such as one or more of 2-fluoroethylamine hydrochloride, 2-chloroethylamine hydrochloride, 2-bromoethylamine hydrochloride, and 3-chloropropylamine hydrochloride. The halogenated arylamine chloride is X-Ph-C. n H 2n -NH3Cl, Ph is a phenylene oxide, n is 1-5 carbon atoms, and X is a halogen; such as one or more of o-fluorophenylethylamine hydrochloride, p-fluorophenylethylamine hydrochloride, o-chloroaniline hydrochloride, 4-bromophenylhydrazine hydrochloride, and 3-bromobenzylamine hydrochloride. Halogenated alkylammonium bromides are XC. n H 2nNH3Br, with 1-5 carbon atoms (n) and X being a halogen; such as one or more of 3-fluoropropylamine hydrobromide, 4-chlorobutylamine hydrobromide, 2-bromoethylamine hydrobromide, and 3-bromopropylamine hydrobromide. The halogenated arylamine bromide is X-Ph-C. n H 2n -NH3Br, Ph is a phenylene oxide, the number of carbon atoms n is 1-5, and X is a halogen; such as one or more of p-fluorophenylethylamine hydrobromide, o-chlorobenzylamine hydrobromide, and p-bromobenzylamine hydrobromide.

[0041] Preferably, the method for preparing a blue perovskite light-emitting diode provided in this embodiment of the invention includes step S10: preparing a perovskite precursor solution, specifically comprising: using any one or a mixture of two of the following materials to form a perovskite: cesium bromide or cesium chloride, or lead bromide or lead chloride; in DMSO solvent, adjusting the concentration of cesium bromide or cesium chloride to 0.1-0.3 mmol, or adjusting the concentration of lead bromide or lead chloride to 0.1-0.3 mmol, to obtain a mixed solution; adjusting the molar ratio of large-group organic halides to lead ions in the perovskite solution to (0.2-1):1, and the molar ratio of halogenated organic halides to lead ions to (0-1):1; thoroughly stirring the mixed solution at 20℃-80℃; filtering the mixed solution using a polytetrafluoroethylene hydrophobic filter membrane with a pore size of 0.22 μm to form a perovskite precursor solution.

[0042] The perovskite precursor solution includes perovskite and doped macrofunctional organohalides and halogenated organohalides. Cesium bromide or cesium chloride concentrations are 0.1-0.3 mmol, and lead bromide or lead chloride concentrations are 0.1-0.3 mmol. Perovskite is formed by any one or a mixture of the two types of materials. The molar ratio of macrofunctional organohalides to lead ions is (0.2-1):1, and the molar ratio of halogenated organohalides to lead ions is (0-1):1.

[0043] Preferably, before step S20: growing the perovskite light-emitting layer, the method for fabricating a blue perovskite light-emitting diode provided in this embodiment of the invention further includes: fabricating a patterned transparent anode layer on a substrate; fabricating an anode interface layer on the patterned transparent anode layer; specifically including the following steps: placing a clean substrate with a patterned transparent anode layer of 50-200 nm thickness on a spin coater holder; adjusting the rotation speed of the spin coater to 1000-5000 r / min, so that the PEDOT:PSS solution is uniformly coated on the patterned transparent anode layer and an anode interface layer is formed on the surface of the patterned transparent anode layer. Figure 1 As shown, substrate 1 is made of transparent materials such as glass or quartz, with a thickness of 1-5 mm. The patterned transparent anode layer 2 is an indium tin oxide electrode with a thickness of 50-200 nm. The anode interface layer 3 is PEDOT:PSS with a thickness of 10-50 nm.

[0044] Correspondingly, the growth of the perovskite luminescent layer specifically includes: growing the perovskite luminescent layer on the anode interface layer. This specifically includes the following steps: preparing a perovskite precursor solution, which includes perovskite and large-group organic halides and halogenated organic halides; uniformly spin-coating the perovskite precursor solution onto the surface of the anode interface layer, controlling the spin-coating speed at 1000-5000 r / min; then placing the substrate with the spin-coated perovskite precursor solution on a hot plate for annealing to form the perovskite luminescent layer. A quasi-two-dimensional low-n phase with high exciton binding energy is formed in the perovskite luminescent layer, regulating efficient and stable blue light emission.

[0045] Preferably, after step S20: growing the perovskite light-emitting layer, the method for fabricating the blue perovskite light-emitting diode provided in this embodiment of the invention further includes: sequentially depositing a cathode interface layer, a cathode interface modification layer, and a cathode layer on the perovskite light-emitting layer in a vacuum coating machine. The cathode interface layer 5 is TPBi with a thickness of 5-50 nm. The cathode interface modification layer 6 is lithium fluoride with a thickness of 0.5-3 nm. The cathode layer 7 is aluminum or silver with a thickness of 20-150 nm.

[0046] The method for fabricating a blue perovskite light-emitting diode provided in this invention includes the following steps:

[0047] A patterned transparent anode layer is fabricated on a substrate;

[0048] An anode interface layer is prepared on a patterned transparent anode layer;

[0049] A perovskite luminescent layer is grown on the anode interface layer. Large-group organic halides and halogenated organic halides are doped in the perovskite precursor solution. The large-group organic halides and halogenated organic halides together act as organic spacers to induce the formation of a quasi-two-dimensional low n phase with high exciton binding energy inside the perovskite luminescent layer, thereby achieving efficient and stable blue light emission.

[0050] A cathode interface layer, a cathode interface modification layer, and a cathode layer are sequentially prepared on the perovskite luminescent layer by evaporation. The specific steps in growing the perovskite luminescent layer are as follows: the substrate with the perovskite luminescent layer is placed in a vacuum coating machine for vacuum treatment. When the vacuum degree reaches 2×10-4 Pa, the cathode interface layer, the cathode interface modification layer, and the cathode layer are sequentially evaporated on the surface of the perovskite luminescent layer.

[0051] Specifically:

[0052] Step 1: Place the cleaned substrate 1 with a patterned transparent anode layer 2 of 50-200nm thickness on the rack of the spin coater. Apply PEDOT:PSS evenly to the entire patterned transparent anode layer 2 through a 0.45μm filter head. Adjust the rotation speed of the spin coater to 1000-5000r / min so that PEDOT:PSS forms an anode interface layer 3 of 10-50nm thickness on the surface of the patterned transparent anode layer. Place it in an oven at 120℃ and heat for 30min.

[0053] Step 2: Transfer the above substrate to the glove box and place the substrate on the rack of the spin coater. Evenly drop the prepared perovskite precursor solution onto the above substrate 1. Adjust the speed of the spin coater to 1000-5000 r / min. After spin coating for 1 min, a perovskite light-emitting layer 4 with a thickness of 20-200 nm is obtained.

[0054] The preparation method of the above perovskite precursor solution is as follows: Dimethyl sulfoxide (DMSO) is used as the solvent; cesium bromide or cesium chloride concentration is 0.1-0.3 mmol; lead bromide or lead chloride concentration is 0.1-0.3 mmol; and any one or a mixture of both materials is used to form perovskite. The molar ratio of the large-group organohalide to lead ions is (0.2-1):1, and the molar ratio of the halogenated organohalide to lead ions is (0-1):1. After thorough stirring at 20℃-80℃, the solution is filtered through a 0.22 μm pore size polytetrafluoroethylene hydrophobic filter membrane to form the perovskite precursor solution.

[0055] Step 3: Place the product obtained in Step 2 into a vacuum coating machine and evacuate it until the vacuum level reaches 2×10⁻⁶. -4 At Pa, a cathode interface layer 5 with a thickness of 5-50 nm, a cathode interface modification layer 6 with a thickness of 0.5-3 nm, and a cathode layer 7 with a thickness of 20-150 nm are sequentially evaporated. Then, performance tests are performed.

[0056] Example 1

[0057] The method for fabricating a blue perovskite light-emitting diode provided in Example 1 includes the following steps:

[0058] Step 1: Place the cleaned 1mm thick glass substrate (with a 120nm thick patterned transparent anode layer) on the rack of the spin coater. Apply PEDOT:PSS evenly to the patterned transparent anode layer through a 0.45μm filter head. Adjust the spin coater speed to 2500r / min to form a 30nm thick anode interface layer of PEDOT:PSS on the surface of the patterned transparent anode layer. Heat in a 120℃ oven for 30min.

[0059] Step 2: Transfer the above substrate to the glove box and place the substrate on the rack of the spin coater. Evenly drop the mixed perovskite precursor solution onto the anode interface layer. Adjust the spin coater speed to 2500 r / min and spin coat for 1 min to obtain a 30 nm thick perovskite light-emitting layer.

[0060] The preparation method of the above perovskite precursor solution is as follows: using dimethyl sulfoxide as solvent, the concentration of cesium bromide is 0.2 mmol, the concentration of lead bromide is 0.15 mmol, the concentration of phenylethyl ammonium bromide is 0.1 mmol, and the concentration of 2-bromoethylamine hydrobromide is 0.05 mmol. The mixture is heated and stirred at 60 °C for 3 hours, then the heating is stopped and the stirring is continued for 12 hours.

[0061] Step 3: Place the product obtained in Step 2 into a vacuum coating machine and evacuate it until the vacuum level reaches 2×10⁻⁶. -4 At Pa, a 20 nm thick TPBi cathode interface layer, a 1 nm thick LiF cathode interface modification layer, and a 120 nm thick Al cathode layer are sequentially evaporated.

[0062] Example 2

[0063] The method for fabricating a blue perovskite light-emitting diode provided in Example 2 includes the following steps:

[0064] Step 1: Place the cleaned 2mm thick glass substrate (with a 50nm thick patterned transparent anode layer) on the rack of the spin coater. Apply PEDOT:PSS evenly to the patterned transparent anode layer through a 0.45μm filter head. Adjust the spin coater speed to 1000r / min to form a 50nm thick anode interface layer of PEDOT:PSS on the surface of the patterned transparent anode layer. Heat in an oven at 120℃ for 30min.

[0065] Step 2: Transfer the above substrate to the glove box and place the substrate on the rack of the spin coater. Evenly drop the mixed perovskite precursor solution onto the anode interface layer. Adjust the spin coater speed to 5000 r / min and spin coat for 1 min to obtain a 20 nm thick perovskite light-emitting layer.

[0066] The preparation method of the above perovskite precursor solution is as follows: using dimethyl sulfoxide as solvent, the concentration of cesium chloride is 0.02 mmol, the concentration of cesium bromide is 0.13 mmol, the concentration of lead bromide is 0.15 mmol, the concentration of phenylethylamine bromide is 0.15 mmol, and the concentration of p-fluorophenylethylamine hydrobromide is 0.03 mmol. The mixture is heated and stirred at 60 °C for 3 hours, then the heating is stopped and stirring is continued for 12 hours.

[0067] Step 3: Place the product obtained in Step 2 into a vacuum coating machine and evacuate it until the vacuum level reaches 2×10⁻⁶. -4At Pa, a 50 nm thick TPBi cathode interface layer, a 2 nm thick LiF cathode interface modification layer, and a 20 nm thick Ag cathode layer are sequentially evaporated.

[0068] Example 3

[0069] The method for fabricating a blue perovskite light-emitting diode provided in Example 3 includes the following steps:

[0070] Step 1: Place the cleaned 5mm thick quartz substrate (with a 200nm thick patterned transparent anode layer) on the rack of the spin coater. Apply PEDOT:PSS evenly to the patterned transparent anode layer through a 0.45μm filter head. Adjust the spin coater speed to 5000r / min to form a 10nm thick anode interface layer of PEDOT:PSS on the surface of the patterned transparent anode layer. Heat in an oven at 120℃ for 30min.

[0071] Step 2: Transfer the above substrate to the glove box and place the substrate on the rack of the spin coater. Evenly drop the mixed perovskite precursor solution onto the anode interface layer. Adjust the spin coater speed to 1000 r / min and spin coat for 1 min to obtain a 200 nm thick perovskite light-emitting layer.

[0072] The preparation method of the above perovskite precursor solution is as follows: using dimethyl sulfoxide as solvent, the concentration of cesium bromide is 0.2 mmol, the concentration of lead bromide is 0.2 mmol, the concentration of propyl ammonium chloride is 0.1 mmol, and the concentration of p-fluorophenylethylamine hydrobromide is 0.03 mmol. The mixture is heated and stirred at 40 °C for 3 hours, then the heating is stopped and the stirring is continued for 12 hours.

[0073] Step 3: Place the product obtained in Step 2 into a vacuum coating machine and evacuate it until the vacuum level reaches 2×10⁻⁶. -4 At Pa, a 5 nm thick TPBi cathode interface layer, a 0.5 nm thick LiF cathode interface modification layer, and an 80 nm thick Al cathode layer are sequentially evaporated.

[0074] Example 4

[0075] The method for fabricating a blue perovskite light-emitting diode provided in Example 4 includes the following steps:

[0076] Step 1: Place the cleaned 2mm thick quartz substrate (with a 50nm thick patterned transparent anode layer) on the rack of the spin coater. Apply PEDOT:PSS evenly to the patterned transparent anode layer through a 0.45μm filter head. Adjust the spin coater speed to 1000r / min to form a 50nm thick anode interface layer of PEDOT:PSS on the surface of the patterned transparent anode layer. Heat in an oven at 120℃ for 30min.

[0077] Step 2: Transfer the above substrate to the glove box and place the substrate on the rack of the spin coater. Evenly drop the mixed perovskite precursor solution onto the anode interface layer. Adjust the spin coater speed to 5000 r / min and spin coat for 1 min to obtain a 50 nm thick perovskite light-emitting layer.

[0078] The preparation method of the above perovskite precursor solution is as follows: using dimethyl sulfoxide as solvent, the concentration of cesium bromide is 0.1 mmol, the concentration of lead chloride is 0.15 mmol, the concentration of butylamine hydrobromide is 0.14 mmol, and the concentration of 3-bromobenzylamine hydrochloride is 0.05 mmol. The mixture is heated and stirred at 40 °C for 3 hours, then the heating is stopped and the stirring is continued for 12 hours.

[0079] Step 3: Place the product obtained in Step 2 into a vacuum coating machine and evacuate it until the vacuum level reaches 2×10⁻⁶. -4 At Pa, a 50 nm thick TPBi cathode interface layer, a 3 nm thick LiF cathode interface modification layer, and a 150 nm thick Ag cathode layer are sequentially evaporated.

[0080] Example 5

[0081] The method for fabricating a blue perovskite light-emitting diode provided in Example 5 includes the following steps:

[0082] Step 1: Place the cleaned 2mm thick quartz substrate (with a 50nm thick patterned transparent anode layer) on the rack of the spin coater. Apply PEDOT:PSS evenly to the patterned transparent anode layer through a 0.45μm filter head. Adjust the spin coater speed to 1000r / min to form a 50nm thick anode interface layer of PEDOT:PSS on the surface of the patterned transparent anode layer. Heat in an oven at 120℃ for 30min.

[0083] Step 2: Transfer the above substrate to the glove box and place the substrate on the rack of the spin coater. Evenly drop the mixed perovskite precursor solution onto the anode interface layer. Adjust the spin coater speed to 5000 r / min and spin coat for 1 min to obtain a 50 nm thick perovskite light-emitting layer.

[0084] The preparation method of the above perovskite precursor solution is as follows: using dimethyl sulfoxide as solvent, the concentration of cesium bromide is 0.2 mmol, the concentration of lead chloride is 0.15 mmol, the concentration of butylamine hydrobromide is 0.05 mmol, and the concentration of 2-fluoroethylamine hydrochloride is 0.1 mmol. Heating is stopped, and stirring is continued for 12 hours.

[0085] Step 3: Place the product obtained in Step 2 into a vacuum coating machine and evacuate it until the vacuum level reaches 2×10⁻⁶. -4At Pa, a 50 nm thick TPBi cathode interface layer, a 3 nm thick LiF cathode interface modification layer, and a 150 nm thick Ag cathode layer are sequentially evaporated.

[0086] Comparative Example 1

[0087] The method for fabricating a blue perovskite light-emitting diode provided in Comparative Example 1 includes the following steps:

[0088] Step 1: Place the cleaned 1mm thick glass substrate (with a 120nm thick patterned transparent anode layer) on the rack of the spin coater. Apply PEDOT:PSS evenly to the patterned transparent anode layer through a 0.45μm filter head. Adjust the spin coater speed to 2500r / min to form a 30nm thick anode interface layer of PEDOT:PSS on the surface of the transparent electrode. Heat in an oven at 120℃ for 30min.

[0089] Step 2: Transfer the above substrate to the glove box and place the substrate on the rack of the spin coater. Evenly drop the mixed perovskite precursor solution onto the anode interface layer. Adjust the spin coater speed to 2500 r / min and spin coat for 1 min to obtain a 30 nm thick perovskite light-emitting layer.

[0090] The preparation method of the above perovskite precursor solution is as follows: using dimethyl sulfoxide as solvent, cesium bromide concentration is 0.2 mmol, lead bromide concentration is 0.15 mmol, phenylethyl ammonium bromide concentration is 0.15 mmol, heating and stirring at 60°C for 3 hours, stopping heating, and continuing stirring for 12 hours.

[0091] Step 3: Place the product obtained in Step 2 into a vacuum coating machine and evacuate it until the vacuum level reaches 2×10⁻⁶. -4 At Pa, a 20 nm thick TPBi cathode interface layer, a 1 nm thick LiF cathode interface modification layer, and a 100 nm thick Al cathode layer are sequentially evaporated.

[0092] Comparative Example 2

[0093] The method for fabricating the blue perovskite light-emitting diode provided in Comparative Example 2 includes the following steps:

[0094] Step 1: Place the cleaned 2mm thick glass substrate (with a 50nm thick patterned transparent anode layer) on the rack of the spin coater. Apply PEDOT:PSS evenly to the patterned transparent anode layer through a 0.45μm filter head. Adjust the spin coater speed to 1000r / min to form a 50nm thick anode interface layer of PEDOT:PSS on the surface of the transparent electrode. Heat in an oven at 120℃ for 30min.

[0095] Step 2: Transfer the above substrate to the glove box and place the substrate on the rack of the spin coater. Evenly drop the mixed perovskite precursor solution onto the anode interface layer. Adjust the spin coater speed to 5000 r / min and spin coat for 1 min to obtain a 20 nm thick perovskite light-emitting layer.

[0096] The preparation method of the above perovskite precursor solution is as follows: using dimethyl sulfoxide as solvent, the concentration of cesium chloride is 0.02 mmol, the concentration of cesium bromide is 0.13 mmol, the concentration of lead bromide is 0.15 mmol, and the concentration of phenylethyl ammonium bromide is 0.15 mmol. The mixture is heated and stirred at 60°C for 3 hours, then the heating is stopped and stirring is continued for 12 hours.

[0097] Step 3: Place the product obtained in Step 2 into a vacuum coating machine and evacuate it until the vacuum level reaches 2×10⁻⁶. -4 At Pa, a 50 nm thick TPBi cathode interface layer, a 2 nm thick LiF cathode interface modification layer, and a 20 nm thick Ag cathode layer are sequentially evaporated.

[0098] Comparative Example 3

[0099] The method for fabricating a blue perovskite light-emitting diode provided in Comparative Example 3 includes the following steps:

[0100] Step 1: Place the cleaned 5mm thick quartz substrate (with a 200nm thick patterned transparent anode layer) on the rack of the spin coater. Apply PEDOT:PSS evenly to the patterned transparent anode layer through a 0.45μm filter head. Adjust the spin coater speed to 5000r / min to form a 10nm thick anode interface layer of PEDOT:PSS on the surface of the transparent electrode. Heat in an oven at 120℃ for 30min.

[0101] Step 2: Transfer the above substrate to the glove box and place the substrate on the rack of the spin coater. Evenly drop the mixed perovskite precursor solution onto the anode interface layer. Adjust the spin coater speed to 1000 r / min and spin coat for 1 min to obtain a 200 nm thick perovskite light-emitting layer.

[0102] The preparation method of the above perovskite precursor solution is as follows: using dimethyl sulfoxide as solvent, cesium bromide concentration is 0.2 mmol, lead bromide concentration is 0.2 mmol, propyl ammonium chloride concentration is 0.1 mmol, heating and stirring at 60°C for 3 hours, stopping heating, and continuing stirring for 12 hours.

[0103] Step 3: Place the product obtained in Step 2 into a vacuum coating machine and evacuate it until the vacuum level reaches 2×10⁻⁶. -4At Pa, a 5 nm thick TPBi cathode interface layer, a 0.5 nm thick LiF cathode interface modification layer, and an 80 nm thick Al cathode layer are sequentially evaporated.

[0104] Comparative Example 4

[0105] The fabrication method of the perovskite light-emitting diode in Comparative Example 4 includes the following steps:

[0106] Step 1: Place the cleaned 2mm thick quartz substrate (with a 50nm thick patterned transparent anode layer) on the rack of the spin coater. Apply PEDOT:PSS evenly to the patterned transparent anode layer through a 0.45μm filter head. Adjust the spin coater speed to 1000r / min to form a 50nm thick anode interface layer of PEDOT:PSS on the surface of the transparent electrode. Heat in an oven at 120℃ for 30min.

[0107] Step 2: Transfer the above substrate to the glove box and place the substrate on the rack of the spin coater. Evenly drop the mixed perovskite precursor solution onto the anode interface layer. Adjust the spin coater speed to 5000 r / min and spin coat for 1 min to obtain a 50 nm thick perovskite light-emitting layer.

[0108] The preparation method of the above perovskite precursor solution is as follows: using dimethyl sulfoxide as solvent, cesium bromide concentration is 0.1 mmol, lead chloride concentration is 0.15 mmol, butylamine hydrobromide concentration is 0.14 mmol, heating and stirring at 60°C for 3 hours, stopping heating, and continuing stirring for 12 hours.

[0109] Step 3: Place the product obtained in Step 2 into a vacuum coating machine and evacuate it until the vacuum level reaches 2×10⁻⁶. -4 At Pa, a 50 nm thick TPBi cathode interface layer, a 3 nm thick LiF cathode interface modification layer, and a 150 nm thick Ag cathode layer are sequentially evaporated.

[0110] Through the above embodiments and comparative examples, it can be concluded that:

[0111] from Figure 2 As can be seen, the absorption spectrum of Example 1 doped with 2-bromoethylamine hydrobromide shows a significant blue shift compared to the absorption spectrum of Comparative Example 1 without 2-bromoethylamine hydrobromide. The absorption peak of the quasi-two-dimensional high n-phase (n≥4) is weakened, while no absorption peak of the two-dimensional phase (n=1) is generated. Obviously, there is a regulatory effect on the formation of the perovskite quasi-two-dimensional phase.

[0112] from Figure 3As can be seen, the photoluminescence peak of the perovskite emitting layer in Example 1 doped with 2-bromoethylamine hydrobromide exhibits a blue shift compared to the photoluminescence peak of the perovskite emitting layer in Comparative Example 1 without doping. This indicates that 2-bromoethylamine hydrobromide can effectively promote the formation of a quasi-two-dimensional low-n phase to achieve the blue shift in the spectrum, thereby realizing the fabrication of a blue perovskite diode.

[0113] from Figure 4 As can be seen, Example 1 maintained a similar start-up voltage to Comparative Example 1, although the brightness and current density decreased at the same voltage.

[0114] from Figure 5 As can be seen, compared with Comparative Example 1, Example 1 has high luminous efficiency at a lower current density, thus improving the luminous efficiency of blue perovskite light-emitting diodes.

[0115] from Figure 6 and Figure 7 As can be seen, the electroluminescence spectra of Example 1 under different bias voltages are almost identical to those of Comparative Example 1 under different bias voltages, demonstrating the regulatory effect of 2-bromoethylamine hydrobromide on the realization of blue light emission and its effective improvement on the luminous stability of blue perovskite light-emitting diodes.

[0116] On the other hand, Table 1 below compares the luminescence performance parameters of Comparative Examples 1, 2, 3, and 4 and Examples 1, 2, 3, 4, and 5. Compared with Comparative Example 1, Example 1 exhibits a bluer emission peak, higher external quantum efficiency, and more stable luminescence performance (wavelength 485 nm, external quantum efficiency 9.67%). Similarly, compared with Comparative Examples 2, 3, and 4, Examples 2, 3, 4, and 5 also exhibit bluer emission peaks, higher external quantum efficiency, and more stable luminescence performance, respectively. This demonstrates that the embodiments of the present invention possess superior luminescence performance and stability compared to their respective comparative examples, thereby illustrating the significant advantages of the method of the present invention in improving the performance of perovskite light-emitting diodes.

[0117] Table 1

[0118]

[0119]

[0120] The above analysis shows that the blue perovskite light-emitting diode provided in this invention simultaneously introduces large-group organic halides and halogenated organic halides into the perovskite system to prepare a blue quasi-two-dimensional perovskite. The combined action of the large-group organic halide amines and halogenated organic halide amines enables the perovskite to form a quasi-two-dimensional n-phase structure, thereby controlling the generation and distribution of the quasi-two-dimensional phase and achieving adjustment of the perovskite's dimensional structure and band gap width. Furthermore, the interaction between the carbon-halogen bonds and amino bonds in the halogenated organic halides and the halide ions in the perovskite increases the exciton binding energy of the blue perovskite, improves the band gap width, suppresses the formation of the two-dimensional phase (n=1), and reduces the generation of the quasi-two-dimensional high-n phase (n≥4), allowing excitons to effectively transfer from the n=2 phase to the n=3 phase. This maintains stable blue light emission while improving the luminous efficiency of the quasi-two-dimensional perovskite. This invention addresses the problems of spectral instability and uncontrollable phase formation and distribution in existing blue perovskite light-emitting diodes, ensuring stable blue light emission from perovskite and improving the luminous efficiency of blue perovskite light-emitting diodes.

[0121] In summary, the above description is merely a preferred embodiment of this specification and is not intended to limit the scope of protection of this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this specification should be included within the scope of protection of this specification.

[0122] The systems, apparatuses, modules, or units described in one or more of the above embodiments may be implemented by a computer chip or entity, or by a product having a certain function. A typical implementation device is a computer. Specifically, a computer may be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smartphone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or any combination of these devices.

[0123] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0124] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

[0125] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

Claims

1. A blue perovskite light-emitting diode, comprising a perovskite light-emitting layer, characterized in that, The perovskite luminescent layer comprises perovskite, a large-group organohalide, and a halogenated organohalide. The large-group organohalide includes organochlorine LCl or organobromine LBr, where L is a monovalent organic amine ion with an ionic radius greater than 300 picometers. The halogenated organohalide includes halogenated organochlorine MCl or halogenated organobromine MBr, where M is a monovalent organic amine ion containing a carbon-halogen bond (CF / C-Cl / C-Br). The halogenated organochlorinated ammonium chloride MCl is a halogenated alkylamine chloride or a halogenated arylamine chloride, and the halogenated organobrominated ammonium chloride MBr is a halogenated alkylamine bromide or a halogenated arylamine bromide, wherein the halogenated alkylammonium chloride is XC. n H 2n NH3Cl, where the alkyl group has 2-5 carbon atoms (n), and X is a halogen; the haloarylamine chloride is X-Ph-C. n H 2n -NH3Cl, Ph is a phenylene oxide, n is 1-5 carbon atoms, and X is a halogen; the haloalkylammonium bromide is XC. n H 2n NH3Br, with n having 1-5 carbon atoms, and X being a halogen; the haloaryl bromide is X-Ph-C n H 2n -NH3Br, Ph is phenylene, the carbon number n is 1-5, and X is a halogen; The perovskite is composed of any one or a mixture of two of the following materials: cesium bromide or cesium chloride, and lead bromide or lead chloride. The molar ratio of the large-group organohalide to lead ions is (0.2-1):1, and the molar ratio of the halogenated organohalide to lead ions is (0-1):

1. The perovskite light-emitting layer has an anode interface layer and a cathode interface layer on both sides, the anode interface layer is polythiophene derivative poly(3,4-vinyldioxythiophene) doped polystyrene sulfonic acid, and / or the cathode interface layer is TPBi. The large-group organohalides also include a cathode interface modification layer and a cathode layer disposed sequentially on the cathode interface layer, wherein the cathode interface modification layer is lithium fluoride, and / or the cathode layer is aluminum or silver. Correspondingly, the anode layer is indium tin oxide.

2. A method for fabricating a blue perovskite light-emitting diode, applicable to the blue perovskite light-emitting diode as described in claim 1, characterized in that, Includes the following steps: Preparation of perovskite precursor solution; Growth of perovskite luminescent layer; The precursor solution comprises perovskite, large-group organohalides, and halogenated organohalides. The large-group organohalides include organochlorines (LCl) or organobromines (LBr), where L is a monovalent organic amine ion with an ionic radius greater than 300 picometers. The halogenated organohalides include halogenated organochlorines (MCl) or halogenated organobromines (MBr), where M is a monovalent organic amine ion containing a carbon-halogen bond (CF / C-Cl / C-Br).

3. The method for fabricating a blue perovskite light-emitting diode according to claim 2, characterized in that, The preparation of perovskite precursor solution specifically includes: Perovskite is formed by using any one or a mixture of two of the following materials: cesium bromide or cesium chloride, and lead bromide or lead chloride. In DMSO solvent, the concentration of cesium bromide or cesium chloride is prepared to be 0.1-0.3 mmol, or the concentration of lead bromide or lead chloride is prepared to be 0.1-0.3 mmol, to obtain a mixed solution; In the perovskite solution, the molar ratio of large-group organic halides to lead ions is (0.2-1):1, and the molar ratio of halogenated organic halides to lead ions is (0-1):

1. The mixed solution was stirred thoroughly at 20℃-80℃; The mixed solution is filtered using a polytetrafluoroethylene hydrophobic filter membrane to form the perovskite precursor solution.

4. The method for fabricating a blue perovskite light-emitting diode according to claim 2 or 3, characterized in that, Before growing the perovskite luminescent layer, the method further includes: A patterned transparent anode layer is fabricated on a substrate; An anode interface layer is prepared on the patterned transparent anode layer; Correspondingly, a perovskite luminescent layer is grown, specifically including: A perovskite luminescent layer is grown on the anode interface layer.

5. The method for fabricating a blue perovskite light-emitting diode according to claim 4, characterized in that, After growing the perovskite luminescent layer, the method further includes: In a vacuum coating machine, a cathode interface layer, a cathode interface modification layer, and a cathode layer are sequentially deposited on the perovskite luminescent layer.

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