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CN-121985707-A - Host-guest complex passivated blue perovskite light-emitting diode and full solution preparation method thereof

CN121985707ACN 121985707 ACN121985707 ACN 121985707ACN-121985707-A

Abstract

In the process of preparing the blue perovskite light-emitting diode by a full solution method, various crown ethers and p-fluorophenylethylamine bromine or p-fluorophenylethylamine chlorine form the host-guest complex, the host-guest complex is doped into an electron transport layer precursor solution and then coated on a perovskite layer, so that the in-situ passivation of the defects of the perovskite light-emitting layer and the preparation of the electron transport layer are realized in one step, the problems of the increase of the defect state of the perovskite light-emitting layer, the aggravation of non-radiative recombination and the like caused by the deposition of the electron transport layer in the traditional full solution preparation method are effectively solved, the long-term operation stability and the electroluminescent quantum yield of a device are effectively improved, and the method has important significance for promoting the large-scale application of the full solution method preparation of the perovskite light-emitting diode.

Inventors

  • WANG ZHIBIN
  • Jiang Naizhong
  • CHEN DAQIN

Assignees

  • 福建师范大学

Dates

Publication Date
20260505
Application Date
20260130

Claims (10)

  1. 1. The full solution preparation method of the host-guest complex passivated blue light perovskite light-emitting diode is characterized in that a hole transmission layer, a perovskite light-emitting layer and an electron transmission layer are sequentially laminated on an anode substrate from bottom to top in a spin coating mode, and then a cathode electrode is deposited, so that the full solution preparation method is prepared, and the full solution preparation method is characterized in that the perovskite light-emitting layer is prepared by using bromochloro Lan Guanggai titanium ore as a material, and the electron transmission layer is formed on the perovskite light-emitting layer in a spin coating mode, and comprises the following specific steps: S1, adding p-fluorophenylethylamine bromide or p-fluorophenylethylamine chloride and crown ether into an organic solvent in which an electron transport layer material is dissolved, and fully dissolving, wherein in the dissolving process, the added p-fluorophenylethylamine bromide or p-fluorophenylethylamine chloride and crown ether self-assemble in the organic solvent to form a host-guest complex, thereby obtaining an electron transport layer precursor solution; S2, spin-coating the electron transport layer precursor solution on the perovskite light-emitting layer to realize passivation of the perovskite light-emitting layer, and obtaining the electron transport layer after spin-coating is completed.
  2. 2. The method for preparing the full solution of the host-guest complex passivated blue perovskite light emitting diode according to claim 1, wherein in the step S1, the concentration of the added p-fluorophenylethylamine bromide or p-fluorophenylethylamine chloride in the electron transport layer precursor solution is 1.5-2.5 mg/mL, and the mass ratio of the added crown ether to the added p-fluorophenylethylamine bromide or p-fluorophenylethylamine chloride is 2:1.
  3. 3. The method for preparing a full solution of a host-guest complex passivated blue full solution perovskite light emitting diode according to claim 1, wherein in step S1, the electron transport layer material is 2,4, 6-tris [3- (diphenylphosphinyloxy) phenyl ] -1,3, 5-triazole, and the organic solvent is chlorobenzene.
  4. 4. The method for preparing the full solution of the host-guest complex passivated blue perovskite light emitting diode according to claim 1, wherein in the step S2, spin coating conditions comprise 2000-2500 r/min and time of 30-40S.
  5. 5. The method for preparing the full solution of the host-guest complex passivated blue perovskite light emitting diode according to claim 1, wherein the precursor solution of the hole transport layer comprises a chlorobenzene solution containing poly [ bis (4-phenyl) (2, 4, 6-trimethylphenyl) amine ] dissolved and a chlorobenzene solution containing poly (9-vinylcarbazole), and the hole transport layer is obtained after spin coating and annealing the chlorobenzene solution containing poly [ bis (4-phenyl) (2, 4, 6-trimethylphenyl) amine ] dissolved and the chlorobenzene solution containing poly (9-vinylcarbazole) on an anode substrate in sequence.
  6. 6. The method for preparing a full solution of a host-guest complex passivated blue perovskite light emitting diode according to claim 1, wherein the bromochloro blue perovskite is one of CsPbBr y Cl (3-y) 、Cs x FA (1-x) PbBr y Cl (3-y) 、Cs x FA (1-x) PbBr y Cl (3-y) :PEABr、Cs x FA (1-x) PbBr y Cl (3-y) :PEACl, wherein x is more than or equal to 0.7 and less than or equal to 0.95, and y is more than or equal to 0.5 and less than or equal to 1.2.
  7. 7. The method for preparing a full solution of a host-guest complex passivated blue perovskite light emitting diode according to claim 6, wherein when the material of the perovskite light emitting layer is Cs x FA (1-x) PbBr y Cl (3-y) : PEABr, the precursor solution of the perovskite light emitting layer is prepared by dissolving cesium bromide, formamidine bromide, lead chloride, p-fluorophenylethylamine bromide, lithium bromide and crown ether in dimethyl sulfoxide solvent, wherein the molar percentage of cesium bromide, formamidine bromide, lead chloride, p-fluorophenylethylamine bromide and lithium bromide is 1.00:0.30:0.57:0.42:0.15:0.11, the total concentration of dissolved Pb 2+ ions in dimethyl sulfoxide solvent is 0.3 mol/L, and the concentration of crown ether in dimethyl sulfoxide solvent is 7 mg/mL; And spin-coating a precursor solution of the perovskite light-emitting layer on the hole transport layer, and annealing to form the perovskite light-emitting layer.
  8. 8. The method for preparing the full solution of the host-guest complex passivated blue perovskite light emitting diode according to claim 1, wherein the rotation speed of spin coating of the precursor solution of the perovskite light emitting layer on the hole transport layer is 4000-4500 r/min.
  9. 9. The method of claim 1, wherein the cathode electrode is a LiF/Al electrode and is deposited on the electron transport layer by vacuum evaporation.
  10. 10. The host-guest complex passivated blue perovskite light emitting diode is characterized by being prepared by the full solution preparation method of the host-guest complex passivated blue perovskite light emitting diode according to any one of claims 1-9.

Description

Host-guest complex passivated blue perovskite light-emitting diode and full solution preparation method thereof Technical Field The invention particularly relates to a host-guest complex passivated blue perovskite light-emitting diode and a full solution preparation method thereof, belonging to the technical field of perovskite light-emitting diodes. Background The metal halide perovskite has the remarkable advantages of adjustable spectrum, high color saturation, low cost and easy preparation, and has become a luminescent material with great application potential in the future illumination and display fields. Compared with Organic Light Emitting Diodes (OLEDs), perovskite light emitting diodes (PeLEDs) developed based on metal halide perovskite have the characteristics of narrow half-width of a light emitting spectrum, high color purity, wide color gamut and the like, and are more ideal light emitting elements. From the structure of the device, peLEDs is mainly composed of an electrode, a Hole Transport Layer (HTL), a perovskite light-emitting layer, an Electron Transport Layer (ETL) and other functional layers, and PeLEDs can realize light emission of multiple colors such as red, green, blue and the like according to different compositions of the perovskite light-emitting layers. However, blue light PeLEDs has a wider band gap and more deep level defects than green and red light PeLEDs, and has poor stability and is currently being developed slowly. Blue light PeLEDs luminescent layer material is usually bromine-chlorine mixed halogen perovskite (such as CsPbBr xCl(3-x)), and because of larger radius difference between two halogen ions, ion migration and halogen phase separation are very easy to occur in the perovskite luminescent layer in the film forming process, so that the luminescent peak red shift and the color purity of the material are reduced, and pure blue light emission is difficult to realize stably. Meanwhile, in the current PeLEDs manufacturing process, the electron transport layer located above the perovskite light-emitting layer is almost all prepared by deposition by a high vacuum evaporation method. The process is long in time consumption, high in production cost, and capable of further preventing the industrialization process of the blue light PeLEDs, and has the outstanding problems of limited device area, low yield and the like. Compared with the vacuum deposition technology, the solution spin coating method is utilized to deposit the electron transport layer so as to realize the full solution method preparation of the perovskite light-emitting diode, and the perovskite light-emitting diode has been gradually and widely focused by virtue of the remarkable advantages of room temperature preparation, low equipment cost, short preparation period, high production efficiency and the like. At present, the efficiency of perovskite light-emitting diode devices prepared by the full solution method is nearly 20% of that of devices prepared by the vacuum evaporation method. However, in the full solution method process, with spin coating and scouring of the electron transport layer solvent on the surface of the perovskite light-emitting layer, the organic ligands and additives on the surface and grain boundary of the perovskite light-emitting layer inevitably lose, so that a large number of defect states are formed, and finally the non-radiative recombination of carriers on the device is aggravated and the efficiency of the device is reduced. Disclosure of Invention In the process of preparing the blue perovskite light-emitting diode by the full solution method, the host-guest complex is doped into an electron transport layer precursor solution and then coated on a perovskite layer, so that the in-situ passivation of defects of the perovskite light-emitting layer and the preparation of the electron transport layer are realized, the problems of defect state increase and non-radiative recombination aggravation of the perovskite light-emitting layer caused by the deposition of the electron transport layer in the traditional full solution preparation method are effectively overcome, the long-term operation stability of a device and the improvement of the electroluminescent external quantum efficiency are remarkably improved, and the method has important significance for promoting the large-scale application of the full solution method preparation of the blue perovskite light-emitting diode. The technical scheme of the invention is as follows: the invention provides a full solution preparation method of a host-guest complex passivated perovskite light-emitting diode, which comprises the following steps of firstly preparing precursor solutions of a hole transmission layer, a perovskite light-emitting layer and an electron transmission layer respectively, then sequentially coating and laminating corresponding precursor solutions on the upper surface of an anode substrate from bottom to top in a spin coa