A perovskite solar cell and its preparation method

Abstract

The present invention provides a perovskite solar cell and a method for preparing the same, comprising a substrate, a nickel oxide hole transport layer, a polypyrrole modified layer, a perovskite absorption layer, an electron transport layer, and electrodes, which are sequentially arranged; the polypyrrole modified layer has a thickness of 1 to 5 nm. By modifying the nickel oxide layer on the nickel oxide hole transport layer, the present invention can, on the one hand, isolate the nickel oxide from direct contact with the perovskite layer, thus preventing nickel oxide from damaging the perovskite. On the other hand, polypyrrole has excellent carrier transport properties, effectively preventing interfacial charge loss. The nitrogen atoms in the pyrrole have good coordination with the divalent metal cations in the perovskite layer, thereby improving the crystallization quality of the perovskite film and thereby increasing the photoelectric conversion efficiency of the cell.

Description

Technical Field

[0001] The present invention belongs to the technical field of solar cells, and in particular relates to a perovskite solar cell and a preparation method thereof. Background Art

[0002] Nickel oxide is a commonly used hole transport layer material in inverse perovskite solar cells, which has the advantages of being stable, cheap and easy to prepare. However, the highly active oxidation states on the surface of nickel oxide, such as Ni 4+ It will corrode the perovskite layer, causing the collapse of the perovskite structure and affecting the photoelectric conversion efficiency and stability of the device. Summary of the Invention

[0003] In view of this, the object of the present invention is to provide a perovskite solar cell and a preparation method thereof, wherein the perovskite solar cell improves the photoelectric conversion efficiency of the cell by modifying nickel oxide with polypyrrole.

[0004] The present invention provides a perovskite solar cell, comprising a substrate, a nickel oxide hole transport layer, a polypyrrole modification layer, a perovskite absorption layer, an electron transport layer and an electrode arranged in sequence;

[0005] The thickness of the polypyrrole modified layer is 1 to 5 nm.

[0006] In the present invention, the polypyrrole modified layer is prepared by electrochemical deposition of pyrrole monomer.

[0007] In the present invention, the perovskite absorption layer is a halide perovskite with a crystal structure of ABX3, wherein A is an organic cation and / or an inorganic cation, B is a divalent metal ion, and X is a halide ion.

[0008] In the present invention, the divalent metal ion is Pb 2+ or Sn 2+ ;

[0009] The halogen ion is selected from I-, Br- or Cl-.

[0010] In the present invention, the material of the electron transport layer is selected from C60, PCBM or tin dioxide.

[0011] In the present invention, the electrode is selected from one or more of a metal electrode, a conductive oxide transparent electrode, a carbon electrode and a graphite electrode.

[0012] The present invention provides a method for preparing a perovskite solar cell according to the above technical solution, comprising the following steps:

[0013] preparing a nickel oxide hole transport layer on a substrate;

[0014] A polypyrrole modified layer was deposited on nickel oxide using an electrochemical method;

[0015] A perovskite absorption layer, an electron transport layer and an electrode are sequentially prepared on the polypyrrole modified layer to obtain a perovskite solar cell.

[0016] In the present invention, the electrochemical deposition method can effectively control the thickness of the polypyrrole modified layer and play a good regulatory role in the performance of the battery device. The electrochemical method of depositing the polypyrrole modified layer on nickel oxide includes:

[0017] A mixture of sodium dodecylbenzenesulfonate solution and pyrrole monomer was used as the electrolyte, and a three-electrode system was used for deposition, with metal platinum as the counter electrode, Ag / AgCl as the reference electrode, and a substrate with a nickel oxide transport layer as the working electrode. Cyclic voltammetry was used for deposition at a voltage of 0.5 to 2 V. After the deposition was completed, the substrate was dried.

[0018] In the present invention, the concentration of the sodium dodecylbenzenesulfonate solution is 0.05 to 0.5 mol / L, and the concentration of the pyrrole monomer is 0.1 to 2 mol / L. After the polypyrrole modification layer is deposited, the drying temperature is 60° C. and the drying time is 1 to 5 hours.

[0019] In the present invention, the method of preparing the perovskite absorption layer is selected from spin coating, blade coating or slit coating.

[0020] The present invention provides a perovskite solar cell comprising a substrate, a nickel oxide hole transport layer, a polypyrrole modified layer, a perovskite absorption layer, an electron transport layer, and electrodes, arranged in sequence; the polypyrrole modified layer has a thickness of 1 to 5 nm. By modifying the nickel oxide layer on the nickel oxide hole transport layer, the present invention can, on the one hand, isolate the nickel oxide from direct contact with the perovskite layer, thus preventing nickel oxide from damaging the perovskite. On the other hand, polypyrrole has excellent carrier transport properties, effectively preventing interfacial charge loss. The nitrogen atoms in the pyrrole have good coordination with the divalent metal cations in the perovskite layer, thereby improving the crystallization quality of the perovskite film and thereby increasing the photoelectric conversion efficiency of the cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a graph showing the photoelectric conversion efficiency of the solar cell prepared in Example 1 of the present invention;

[0022] Figure 2 This is a graph showing the photoelectric conversion efficiency of the solar cell prepared in Example 2 of the present invention;

[0023] Figure 3 This is a graph showing the photoelectric conversion efficiency of the solar cell prepared in Comparative Example 1 of the present invention;

[0024] Figure 4This is a graph showing the photoelectric conversion efficiency of the solar cell prepared in Comparative Example 2 of the present invention. DETAILED DESCRIPTION

[0025] In order to further illustrate the present invention, a perovskite solar cell and a preparation method thereof provided by the present invention are described in detail below in conjunction with examples, but they should not be understood as limiting the scope of protection of the present invention.

[0026] Example 1

[0027] The FTO glass substrate was cleaned with acetone, isopropanol and deionized water in turn, dried and then treated with UV-ozone for 20 minutes. A nickel oxide hole transport layer was deposited on the substrate by magnetron sputtering with a vacuum pressure of 0.37 Pa, a power of 90 W and a deposition time of 10 minutes. Sodium dodecylbenzenesulfonate was dissolved in deionized water with a concentration of 0.1 mol / L, and pyrrole monomer was added to the solution with a concentration of 0.1 mol / L to prepare an electroplating solution. Polypyrrole was deposited using a three-electrode system with platinum as the counter electrode, Ag / AgCl as the reference electrode, and the substrate with the nickel oxide transport layer as the working electrode. Cyclic voltammetry was used for deposition with a voltage of 0.5-2 V. After 20 cycles, the substrate was removed, rinsed with deionized water, and dried at 60°C for 5 hours. A FAPbI3 perovskite precursor solution (the solutes in the perovskite precursor solution are FAI, PbI2, and MACl, with a molar ratio of PbI2 to FAI of 1:1 and a molar ratio of MACl to PbI2 of 0.35:1) was prepared in a nitrogen glove box at a concentration of 1.4 mol / L. The solvent was a mixture of DMF and DMSO in a 9:1 volume ratio. Fifty microliters of the perovskite precursor solution was dropped onto the substrate and spin-coated at 5000 rpm for 15 seconds. After the 10th second, 150 microliters of anhydrous ether was added, and the substrate was annealed at 150°C for 20 minutes. Finally, a 20 nm thick C60 layer, a 5 nm thick 2,9-dimethyl-4,7-biphenyl-1,10-phenanthroline (BCP) buffer layer, and a 150 nm thick copper electrode were deposited sequentially by vacuum evaporation.

[0028] In the perovskite solar cell prepared in Example 1 of the present invention, the nickel oxide charge transport layer is 30 nm, the polypyrrole is 2 nm, the perovskite layer is 400 nm, the C60 is 20 nm, and the copper electrode is 150 nm.

[0029] Example 2

[0030] The difference from Example 1 is that the thickness of the polypyrrole modified layer is 5 nm.

[0031] Comparative Example 1

[0032] The difference from Example 1 is that the thickness of the polypyrrole modified layer is 10 nm.

[0033] Comparative Example 2

[0034] The difference from Example 1 is that no polypyrrole modification layer is provided.

[0035] Performance testing:

[0036] At room temperature, using a 3A solar simulator, at 100mW / cm 2 The photoelectric conversion efficiency of the cells prepared in the embodiment and the comparative example was tested under the light intensity of 0.09 cm. 2 .

[0037] The test results are as follows Figures 1 to 4 , Figure 1 It can be seen that the short-circuit current density of the battery prepared in Example 1 is 24.67 mA / cm 2 , open circuit voltage 1.116V, fill factor 82.15%, photoelectric conversion efficiency 22.61%;

[0038] Figure 2 It can be seen that the short-circuit current density of the battery prepared in Example 2 is 25.44 mA / cm 2 , open circuit voltage 1.134V, fill factor 78.94%, photoelectric conversion efficiency 22.78%;

[0039] Figure 3 It can be seen that the short-circuit current density of the battery prepared in Comparative Example 1 is 24.25 mA / cm 2 , open circuit voltage 1.033V, fill factor 80.56%, photoelectric conversion efficiency 20.21%;

[0040] Figure 4 It can be seen that the short-circuit current density of the battery prepared in Comparative Example 2 is 24.68 mA / cm 2 , open circuit voltage 1.085V, fill factor 81.83%, and photoelectric conversion efficiency 21.93%.

[0041] As can be seen from the above embodiments, the present invention provides a perovskite solar cell comprising a substrate, a nickel oxide hole transport layer, a polypyrrole modified layer, a perovskite absorption layer, an electron transport layer, and an electrode, arranged in sequence; the polypyrrole modified layer has a thickness of 1 to 5 nm. By modifying the nickel oxide layer on the nickel oxide hole transport layer, the present invention can, on the one hand, isolate the nickel oxide from direct contact with the perovskite layer, thus preventing nickel oxide from damaging the perovskite. On the other hand, polypyrrole has excellent carrier transport properties, which can effectively prevent interfacial charge loss. The nitrogen atoms in the pyrrole have a good coordination effect with the divalent metal cations in the perovskite layer, which can improve the crystallization quality of the perovskite film and thus improve the photoelectric conversion efficiency of the cell.

[0042] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for preparing a perovskite solar cell, comprising the following steps: preparing a nickel oxide hole transport layer on a substrate; A polypyrrole modified layer is deposited on nickel oxide using an electrochemical method; the thickness of the polypyrrole modified layer is 1-5 nm; Sequentially preparing a perovskite absorption layer, an electron transport layer, and an electrode on the polypyrrole modified layer to obtain a perovskite solar cell; Electrochemical methods for depositing polypyrrole modified layers on nickel oxide include: A mixture of sodium dodecylbenzenesulfonate solution and pyrrole monomer was used as the electrolyte, and a three-electrode system was used for deposition. Platinum metal was used as the counter electrode, Ag / AgCl was used as the reference electrode, and the substrate with a nickel oxide transport layer was used as the working electrode. Cyclic voltammetry was used for deposition at a voltage of 0.5~2V. After the deposition was completed, the substrate was dried.

2. The preparation method according to claim 1, characterized in that The polypyrrole modified layer is prepared by electrochemical deposition of pyrrole monomers.

3. The preparation method according to claim 1, characterized in that The perovskite absorption layer is a halide perovskite with a crystal structure of ABX3, wherein A is an organic cation and / or an inorganic cation, B is a divalent metal ion, and X is a halide ion.

4. The preparation method according to claim 3, characterized in that The divalent metal ion is Pb 2+ or Sn 2+ ; The halogen ion is selected from I - Br - or Cl - .

5. The preparation method according to claim 1, characterized in that The material of the electron transport layer is selected from C60, PCBM or tin dioxide.

6. The preparation method according to claim 1, characterized in that The concentration of the sodium dodecylbenzenesulfonate solution in the electrolyte is 0.05-0.5 mol / L, and the concentration of the pyrrole monomer is 0.1-2 mol / L.

7. The preparation method according to claim 1, characterized in that The perovskite absorber layer is prepared by spin coating, blade coating or slit coating.

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