Perovskite thin film containing three-dimensional cage type passivator and solar cell
By using the stereocage passivator PEPA in perovskite solar cells to passivate halogen vacancy defects, the efficiency and stability problems caused by halogen vacancy defects in perovskite solar cells are solved, and higher photoelectric conversion efficiency and more stable battery performance are achieved.
Patent Information
- Application Number
- CN202411965548.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-04-15
AI Technical Summary
The existence of halogen vacancy defects in perovskite solar cells leads to non-radiative recombination losses of carriers, limiting the photoelectric conversion efficiency and stability of the battery.
The three-dimensional cage passivator 4-hydroxymethyl-2,6,7-trioxy-1-phosphabicyclic[2.2.2]octane 1-oxide (PEPA) is used as the passivator. Through its coordination with the perovskite octahedral crystal structure, the halogen vacancy defect is passivated and the non-radiative recombination of carriers is reduced.
It effectively reduces halogen vacancy defects in perovskite films and improves the photoelectric conversion efficiency and stability of perovskite solar cells, especially under harsh conditions such as heating and lighting.
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Figure CN119836120A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of perovskite solar cells, and in particular relates to a perovskite film and a solar cell comprising a three-dimensional cage passivator. Background Art
[0002] Solar cells can directly convert solar energy into electrical energy and are a key technology for promoting the large-scale development of new energy. In recent years, perovskite solar cells have attracted widespread attention from researchers due to their high efficiency and low cost, showing broad application prospects and commercial potential, and are expected to change the existing photovoltaic market structure and provide a stable energy supply for social development.
[0003] Perovskite solar cells are a new type of thin-film solar cells with perovskite thin films as light absorption layers. Their photoelectric conversion efficiency is closely related to the quality of the perovskite thin films. Perovskite used in high-efficiency cells is a metal halide material and also an ionic crystal. During the process of crystallization and film formation, defects will inevitably occur in the perovskite thin film due to the thermodynamic differences between organic and inorganic components and the presence of ion movement under annealing conditions. Among these defects, the most common is the halogen vacancy defect, and the halogen vacancy defects at the grain boundaries and surfaces are much higher than the halogen vacancy defects inside the crystal. The presence of halogen vacancy defects will not only cause non-radiative recombination losses of carriers in the perovskite film, thereby limiting the high photoelectric conversion efficiency of the perovskite solar cell, but also aggravate the ion migration in the perovskite film, especially when the battery is in working condition, thereby causing the perovskite to decompose and lead to battery failure. Therefore, the iodine vacancy defects in the perovskite film will seriously damage the photoelectric performance and stability of the battery, limiting the commercial application of perovskite solar cells. Summary of the invention
[0004] Based on the above analysis, reducing halogen vacancy defects in perovskite films is an effective strategy to improve the photoelectric performance of perovskite solar cells and enhance the stability of the cells, and has high commercial value. The purpose of the present invention is to solve the problems existing in the above-mentioned prior art and provide a perovskite film and solar cell containing a three-dimensional cage passivator. In the perovskite film containing a three-dimensional cage passivator provided by the present invention, the perovskite material is Cs X MA Y FA 1-X-Y PbI Z Br 3-Z , where MA is CH3NH3 + , FA is CH5N2 +, X and Y are between 0 and 1 and X+Y is not greater than 1, Z is between 0 and 3, and the three-dimensional cage passivator is 4-hydroxymethyl-2,6,7-trioxo-1-phosphabicyclo[2.2.2]octane 1-oxide, referred to as PEPA. The molar percentage of the added passivator PEPA relative to the perovskite is between 0.03% and 1%. PEPA is a three-dimensional cage structure with multiple passivation sites that can match the perovskite octahedral crystal structure. The phosphorus atoms in the PEAI molecule can passivate the defects of multiple adjacent sites, reduce the non-radiative recombination of carriers in the perovskite film, and improve the photoelectric conversion efficiency of the corresponding perovskite solar cell. At the same time, compared with the currently commonly used passivation atoms such as sulfur, oxygen, and nitrogen, phosphorus atoms have higher binding energy with lead atoms in perovskite, which can stabilize the perovskite structure and improve the stability of perovskite solar cells, especially under harsh conditions such as heating and illumination.
[0005] Furthermore, the obtained perovskite film containing a three-dimensional cage passivator is applied to a formally structured perovskite solar cell, which comprises, from bottom to top, a conductive substrate, an electron transport layer, a perovskite layer containing a three-dimensional cage passivator, a passivation layer, a hole transport layer, and an electrode.
[0006] The conductive substrate is one of fluorine-doped tin oxide (FTO), indium-doped tin oxide (ITO), and silicon wafer, and preferably the substrate is FTO.
[0007] The electron transport layer is one of titanium dioxide (TiO2), tin dioxide (SnO2), and zinc oxide (ZnO). Preferably, the electron transport layer is TiO2, and the thickness of the electron transport layer is 5nm to 50nm.
[0009] The thickness of the perovskite layer containing the three-dimensional cage passivator is 400nm-1000nm.
[0010] The passivation layer is one of phenylethylamine iodine (PEAI), 4-methoxyphenylethylamine iodine (MeO-PEAI), o-fluorophenylethylamine iodine (oF-PEAI), and BA2PbI4 (BA is butylamine). The passivation layer is preferably PEAI, and the thickness of the passivation layer is 3nm to 50nm.
[0011] The hole transport layer is one of polytriarylamine (PTAA) and 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), preferably Spiro-OMeTAD, and the hole transport layer has a thickness of 50nm to 200nm.
[0012] The electrode is one of an Au electrode, an Ag electrode, a Cu electrode and a C electrode, preferably an Au electrode, and the electrode thickness is 50nm to 100nm.
[0013] The obtained perovskite film containing a three-dimensional cage passivator can also be applied to a trans-structured perovskite solar cell. The perovskite solar cell comprises, from bottom to top, a conductive substrate, a hole transport layer, a perovskite layer containing a three-dimensional cage passivator, a passivation layer, an electron transport layer, and an electrode.
[0014] The conductive substrate is one of FTO, ITO and silicon wafer, and the preferred substrate is ITO.
[0015] The hole transport layer is nickel oxide (NiO X ), [4-(3,6-dimethoxy-9H-carbazole-9-yl)butyl]phosphonic acid (MeO-4PACz), [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACz) or one or more thereof. MeO-4PACz is preferred, and the thickness of the hole transport layer is 2nm to 50nm.
[0016] The thickness of the perovskite layer containing the three-dimensional cage passivator is 400nm-1000nm.
[0017] The passivation layer is one of PEAI, MeO-PEAI, oF-PEAI, and phenylethylamine iodine (PEACl), and preferably the passivation layer is PEAI.
[0018] The electron transport layer is PCBM / 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and C 60 / BCP, preferably C 60 / BCP, the thickness of the electron transport layer is 5nm~50nm.
[0019] The electrode is one of an Au electrode, an Ag electrode, a Cu electrode and a C electrode, preferably an Ag electrode, and the electrode thickness is 50nm to 100nm.
[0020] The perovskite film containing a three-dimensional cage passivator proposed by the present invention can use the three-dimensional cage passivator PEPA to passivate the I-vacancy defects at the grain boundary and the surface. Due to the three-dimensional cage structure of the PEPA molecule, it can match the perovskite octahedral crystal structure, and the phosphorus atoms in the PEAI molecule can passivate the defects of multiple adjacent sites, which has a beneficial effect on the preparation of efficient perovskite solar cells. At the same time, compared with the currently commonly used passivation atoms such as sulfur, oxygen, and nitrogen, the phosphorus atoms have a higher binding energy with the lead atoms in the perovskite, which can stabilize the perovskite structure and improve the stability of the perovskite solar cell, especially the stability under harsh conditions such as heating and illumination, which has a beneficial effect on promoting the practical application of perovskite solar cells. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 Schematic diagram of the molecular structure of a three-dimensional cage additive;
[0022] Figure 2 The following are Fourier infrared spectra of the three-dimensional cage additive powder, the untreated perovskite film, and the perovskite film containing the three-dimensional cage passivator. The results show that the three-dimensional cage passivator is incorporated into the perovskite film.
[0023] Figure 3 The time-resolved fluorescence spectra of untreated perovskite film and perovskite film containing three-dimensional cage passivation agent are shown in Figure 1. The results show that three-dimensional cage passivation agent can increase the carrier lifetime of perovskite film.
[0024] Figure 4 This is a schematic diagram of the structure of a perovskite solar cell containing a three-dimensional cage passivator. The cell structure from bottom to top is FTO conductive substrate, TiO2 electron transport layer, perovskite film containing a three-dimensional cage passivator, PEAI passivation layer, Spiro-OMeTAD hole transport layer, and Au electrode.
[0025] Figure 5 The figure shows the current density-voltage curve of a perovskite solar cell containing an untreated perovskite solar cell and a three-dimensional cage passivator. The cell structure from bottom to top is an FTO conductive substrate, a TiO2 electron transport layer, an untreated perovskite film or a perovskite film containing a three-dimensional cage passivator, a PEAI passivation layer, a Spiro-OMeTAD hole transport layer, and an Au electrode.
[0026] Implementation Examples The implementation examples of the present invention will be further explained in a clear and complete manner in combination with the examples of the present invention and the accompanying drawings. The described examples are only a part of all the examples of the present invention, and the present invention is not limited to the examples.
[0027] Example 1
[0028] This embodiment is to apply the perovskite film containing a three-dimensional cage passivator in a formal structure perovskite solar cell. The cell structure is from bottom to top: a transparent conductive substrate FTO, a TiO2 electron transport layer, a FAPbI3 perovskite absorption layer containing a three-dimensional cage passivator, a PEAI passivation layer, a Spiro hole transport layer, and an Au electrode.
[0029] This embodiment includes the following steps:
[0030] (1) Cleaning the substrate: The FTO conductive glass substrate was ultrasonically cleaned in the order of water-ethanol-water for 15 minutes each. After ultrasonic cleaning, the substrate was blown dry with nitrogen and placed in a drying oven for later use.
[0031] (2) Preparation of TiO2 electron transport layer: The substrate was treated with ozone for 10 minutes using a UV cleaner. At the same time, 3 mL of TiCl4 was added to 200 mL of deionized water to prepare a TiO2 water bath precursor solution. The ozone-treated FTO substrate was then immersed in the TiO2 water bath precursor solution at 70°C for 40 minutes.
[0032] (3) Preparation of perovskite absorption layer:
[0033] a. Treat the TiO2 substrate deposited in step (2) with ozone in a UV cleaning machine for 10 minutes, add 691.515 mg of PbI2 powder and 0.5 mg of PEPA into a mixed solvent of 1 mL of DMF (dimethylformamide) and DMSO (dimethyl sulfoxide), with a volume ratio of DMF to DMSO of 9:1, and shake to obtain a PbI2 precursor solution containing a three-dimensional cage passivator. Place the TiO2 substrate in a glove box, spin-coat the PbI2 precursor solution containing a three-dimensional cage passivator on the TiO2 substrate at a speed of 1500 rpm for 30 seconds, and then anneal on a hot plate at 70°C for 1 minute.
[0034] b. Weigh 90 mg of FAI and 13 mg of MACl, add them together into 1 mL of IPA solvent, and shake to obtain an organic ammonium salt solution. Spin-coat the prepared organic ammonium salt solution on the PbI2 film containing a three-dimensional cage passivator at a speed of 1800 rpm for 30 seconds. After spin coating, take out the sample from the glove box and anneal at 150°C in an air environment for 15 minutes to obtain a perovskite film containing a three-dimensional cage passivator.
[0035] (4) Preparation of passivation layer: Weigh 4.5 mg of PEAI, add it to 1 mL of IPA solvent, and shake to obtain a PEAI precursor solution. Put the perovskite film containing the three-dimensional cage passivator prepared in step (3) into a glove box, and spin-coat the PEAI precursor solution on the perovskite layer at a speed of 4000 rpm for 30 seconds to prepare a passivation layer.
[0036] (5) Preparation of Spiro-OMeTAD hole transport layer: Prepare 70 mg / mL Spiro-OMeTAD solution, and spin-coat the Spiro-OMeTAD solution on the perovskite film by spin coating at a speed of 4000 rpm for 30 seconds;
[0037] (6) Preparation of Au electrode: The Au electrode was prepared by vacuum thermal evaporation method. The thickness of the Au electrode was about 60 nm.
[0038] At this point, a perovskite film containing a three-dimensional cage passivator has been successfully prepared and used as a light absorption layer in a formal perovskite solar cell.
[0039] Example 2
[0040] This embodiment is to apply the perovskite film containing a three-dimensional cage passivation agent to a regular structure perovskite solar cell. The cell structure is as follows from bottom to top: a transparent conductive substrate FTO, a TiO2 electron transport layer, a FA containing a three-dimensional cage passivation agent 0.85 MA 0.15 PbI3 perovskite absorption layer, MeO-PEAI passivation layer, Spiro hole transport layer, Au electrode.
[0041] This embodiment includes the following steps:
[0042] (1) Cleaning the substrate: The FTO conductive glass substrate was ultrasonically cleaned in the order of water-ethanol-water for 15 minutes each. After ultrasonic cleaning, the substrate was blown dry with nitrogen and placed in a drying oven for later use.
[0043] (2) Preparation of TiO2 electron transport layer: The substrate was treated with ozone for 10 minutes using a UV cleaner. At the same time, 3 mL of TiCl4 was added to 200 mL of deionized water to prepare a TiO2 water bath precursor solution. The ozone-treated FTO substrate was then immersed in the TiO2 water bath precursor solution at 70°C for 40 minutes.
[0044] (3) Preparation of perovskite absorption layer:
[0045] a. Preparation of perovskite solution: 1.5 mL of 1.86 molar perovskite solution was prepared, the solvent was a mixture of 1300 μL DMF and 200 μL DMSO, the solute was composed of 1286.2 mg PbI2 and 443.5 mg MAI, 1 mg PEPA was added to 1.5 mL of 1.86 molar perovskite solution to obtain a perovskite solution containing a three-dimensional cage passivator.
[0046] b. Preparation of perovskite film: The perovskite layer was prepared on the hole transport layer by spin coating at a rotation speed of 4000 rpm for 18 s. At the 10th s, 900 μL of ether was added as an anti-solvent. After spin coating, the film was annealed for 30 minutes at a temperature of 100°C.
[0047] (4) Preparation of passivation layer: 4.5 mg of MeO-PEAI was weighed and added to 1 mL of IPA solvent, and oscillated to obtain a PEAI precursor solution. The MeO-PEAI precursor solution was spin-coated on the perovskite layer at a speed of 4000 rpm for 30 s to prepare a passivation layer.
[0048] (5) Preparation of Spiro-OMeTAD hole transport layer: Prepare 70 mg / mL Spiro-OMeTAD solution, and spin-coat the Spiro-OMeTAD solution on the perovskite film by spin coating at a speed of 4000 rpm for 30 seconds;
[0049] (6) Preparation of Au electrode: The Au electrode was prepared by vacuum thermal evaporation method. The thickness of the Au electrode was about 60 nm.
[0050] At this point, a perovskite film containing a three-dimensional cage passivator has been successfully prepared and used as a light absorption layer in a formal perovskite solar cell.
[0051] Example 3
[0052] This embodiment is to apply the perovskite film containing a three-dimensional cage passivator to an inverted perovskite solar cell. The cell structure is as follows from bottom to top: a transparent conductive substrate ITO, a MeO-4PACz hole transport layer, a perovskite absorption layer containing a three-dimensional cage passivator, and the perovskite is FA 0.87 MA 0.08 Cs 0.05 PbI3, PEAI passivation layer, C 60 / BCP electron transport layer, Ag electrode.
[0053] This embodiment includes the following steps:
[0054] (1) Cleaning the substrate: The ITO conductive glass substrate was ultrasonically cleaned in the order of water-ethanol-water for 15 minutes each. After ultrasonic cleaning, the substrate was blown dry with nitrogen and placed in a drying oven for later use.
[0055] (2) Preparation of MeO-4PACz electron transport layer: The substrate was treated with ozone for 10 minutes using a UV cleaning machine. At the same time, 0.5 mg of MeO-4PACz was added to 1 mL of isopropanol to prepare a MeO-4PACz solution, which was then spin-coated on the ITO substrate at a speed of 4000 rpm for 30 seconds. After spin coating, annealing was performed for 10 minutes at a temperature of 100°C.
[0056] (3) Preparation of perovskite absorption layer:
[0057] a. Preparation of perovskite solution: 1 mL of 1.5 molar perovskite solution was prepared, the solvent was a mixture of 800 μL DMF and 200 μL DMSO, the solute was composed of 691.5 mg PbI2, 19.5 mg CsI, 224.4 mg FAI, and 19.08 mg MAI, 0.5 mg PEPA was added to 1 mL of 1.5 molar perovskite solution to obtain a perovskite solution containing a three-dimensional cage passivator.
[0058] b. Preparation of perovskite film: The perovskite layer was prepared on the hole transport layer by spin coating at a speed of 5000 rpm for 40 s. At 35 s, 900 μL of ether was added as an anti-solvent. After spin coating, the film was annealed for 15 minutes at a temperature of 130°C.
[0059] (4) Preparation of passivation layer: Weigh 4.5 mg of PEAI, add it into 1 mL of IPA solvent, and shake to obtain a PEAI precursor solution. Spin-coat the prepared perovskite film containing a three-dimensional cage passivator at a speed of 4000 rpm for 30 seconds to prepare a passivation layer.
[0060] (5) Preparation of C 60 / BCP electron transport layer: 15nm C60 and 7nm BCP were prepared by vacuum thermal evaporation method;
[0061] (6) Preparation of Ag electrode: Ag electrode was prepared by vacuum thermal evaporation method, and the thickness of Ag electrode was about 100 nm.
[0062] At this point, a perovskite film containing a three-dimensional cage passivator has been successfully prepared and used as a light absorption layer in an inverse perovskite solar cell.
[0063] The above-described embodiments are only preferred embodiments of the present invention and do not limit the present invention. Any non-essential modifications, replacements and improvements made by those skilled in the art within the spirit and principle of the present invention shall fall within the scope of the present invention and the technical scope shall be determined according to the scope of the claims.
Claims
1. A perovskite film comprising a three-dimensional cage passivator, characterized in that: The perovskite material is Cs X MA Y FA 1-X- Y PbI Z Br 3-Z , where MA is CH3NH3 + , FA is CH5N2 + , X and Y are between 0 and 1 and X+Y is not greater than 1, Z is between 0 and 3, the three-dimensional cage passivator is 4-hydroxymethyl-2,6,7-trioxo-1-phosphabicyclo[2.2.2]octane 1-oxide, and the molar percentage of the added passivator relative to the perovskite is between 0.03% and 1%.
2. According to the perovskite film containing a three-dimensional cage passivator according to claim 1, a perovskite solar cell containing a three-dimensional cage passivator is further obtained, characterized in that The battery structure from bottom to top is: conductive substrate, electron transport layer, perovskite layer containing three-dimensional cage passivator, passivation layer, hole transport layer, and electrode. a. The conductive substrate is one of fluorine-doped tin oxide (FTO), indium-doped tin oxide (ITO), and silicon wafer. b. The electron transport layer is one of titanium dioxide (TiO2), tin dioxide (SnO2), and zinc oxide (ZnO), and the thickness of the electron transport layer is 5nm to 50nm. c. The thickness of the perovskite layer containing the three-dimensional cage passivator is 400nm to 1000nm. d. The passivation layer is one of phenylethylamine iodine (PEAI), 4-methoxyphenylethylamine iodine (MeO-PEAI), o-fluorophenylethylamine iodine (oF-PEAI), and BA2PbI4 (BA is butylamine), and the thickness of the passivation layer is 3nm to 50nm. e. The hole transport layer is one of polytriarylamine (PTAA) and 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), and the hole transport layer has a thickness of 50nm to 200nm. f. The electrode is one of an Au electrode, an Ag electrode, a Cu electrode, and a C electrode, and the electrode thickness is 50nm to 100nm.
3. According to the perovskite film containing a three-dimensional cage passivator according to claim 1, a perovskite solar cell containing a three-dimensional cage passivator is further obtained, characterized in that The battery structure from bottom to top is: conductive substrate, hole transport layer, perovskite layer containing three-dimensional cage passivator, passivation layer, electron transport layer, and electrode. a. The conductive substrate is one of fluorine-doped tin oxide (FTO), indium-doped tin oxide (ITO), and silicon wafer. b. The hole transport layer is nickel oxide (NiO X ), [4-(3,6-dimethoxy-9H-carbazole-9-yl)butyl]phosphonic acid (MeO-4PACz), [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (Me-4PACz) or one or more combinations thereof, and the thickness of the hole transport layer is 2nm to 50nm. c. The thickness of the perovskite layer containing the three-dimensional cage passivator is 400nm to 1000nm. d. The passivation layer is one of phenylethylamine iodine (PEAI), 4-methoxyphenylethylamine iodine (MeO-PEAI), o-fluorophenylethylamine iodine (oF-PEAI), and phenylethylamine iodine (PEACl), and the thickness of the passivation layer is 3nm to 50nm. e. The electron transport layer is one of PCBM / 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and C60 / BCP, and the thickness of the electron transport layer is 5nm to 50nm. f. The electrode is one of an Au electrode, an Ag electrode, a Cu electrode, and a C electrode, preferably an Ag electrode, and the electrode thickness is 50 nm to 100 nm.