Narrow bandgap perovskite battery and preparation method thereof, all-perovskite stacked battery, and power-using device

Abstract

This application relates to a narrow bandgap perovskite solar cell and its fabrication method, an all-perovskite tandem solar cell, and an electrical device. The narrow bandgap perovskite solar cell includes a first electrode layer, a functional layer, and a second electrode layer stacked together. The functional layer includes a hole transport layer and a narrow bandgap perovskite layer stacked together. The hole transport layer is made of materials including N4,N4'-di(4-vinylphenyl)-N4,N4'-di-1-naphthylbiphenyl-4,4'-diamine, and self-assembled monolayer molecular materials. The narrow bandgap perovskite solar cell exhibits good stability and high photoelectric conversion efficiency.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and in particular to a narrow-bandgap perovskite cell and a preparation method thereof, an all-perovskite stacked cell, and an electrical device. Background Art

[0002] Perovskite solar cell technology is currently the most widely watched new photovoltaic technology. Its photoelectric conversion efficiency has developed rapidly in the past decade, jumping from 3.8% in 2009 to 26% in 2023. Therefore, the industry's demand for the industrialization of this new photovoltaic technology is increasing.

[0003] The preparation of all-perovskite tandem cells is one of the important solutions to further improve the photoelectric conversion efficiency of perovskite solar cells. The preparation of all-perovskite tandem cells depends on narrow-bandgap perovskite solar cells. In the current narrow-bandgap perovskite solar cells, the most commonly used hole transport layer is PEDOT:PSS, which is hygroscopic and acidic, which is considered to be the root cause of the poor stability of narrow-bandgap perovskite cells and all-perovskite tandem cells; the other is the inorganic hole material NiOx commonly used in inverted perovskite solar cells. Although it has good stability and does not have the problems of acidity and hygroscopicity, its energy band position does not match the narrow-bandgap perovskite, and the performance of the narrow-bandgap perovskite cells prepared by this is mostly unsatisfactory.

[0004] Therefore, there is an urgent need to develop a material solution whose energy band position can match narrow-bandgap perovskite and can replace traditional hole transport layer materials to achieve better stability and photoelectric conversion efficiency. Summary of the invention

[0005] Based on this, the present application provides a narrow-bandgap perovskite cell with good stability and high photoelectric conversion efficiency and a preparation method thereof, as well as a full perovskite stacked cell and an electrical device comprising the narrow-bandgap perovskite cell.

[0006] In a first aspect of the present application, a narrow-bandgap perovskite cell is provided, comprising a first electrode layer, a functional layer, and a second electrode layer which are stacked; the functional layer comprises a hole transport layer and a narrow-bandgap perovskite layer which are stacked; the material of the hole transport layer comprises N4,N4`-di(4-vinylphenyl)-N4,N4`-di-1-naphthylbiphenyl-4,4`-diamine (VNPB) and a self-assembled monolayer molecular material.

[0007] In one embodiment, the molar mass ratio of the molecular self-assembled monolayer molecular material to the N4,N4`-di(4-vinylphenyl)-N4,N4`-di-1-naphthylbiphenyl-4,4`-diamine is 1:2~2:1.

[0008] In one embodiment, the self-assembled monolayer molecular material includes one or more of MeO-2PACz, 2PACz, 4PACz and Me-4PACz.

[0009] In one embodiment, the narrow bandgap perovskite layer has a bandgap range of 1.1 eV to 1.55 eV.

[0010] In one embodiment, the material of the narrow bandgap perovskite layer includes a general formula of Cs x FA y MA （1-x-y） Sn z Pb （1-z） I r Br （1-r） A material where 1≥x≥0, 1≥y≥0, 1≥z≥0, 1≥r≥0.

[0011] The second aspect of the present application provides a method for preparing the narrow bandgap perovskite cell according to the first aspect, comprising the following steps:

[0012] Preparing the functional layer on the surface of the first electrode layer;

[0013] Preparing the second electrode layer on the surface of the functional layer;

[0014] The process of preparing the functional layer includes the step of preparing the hole transport layer, and the step includes:

[0015] The N4,N4`-di(4-vinylphenyl)-N4,N4`-di-1-naphthylbiphenyl-4,4`-diamine, the self-assembled monolayer molecular material and the solvent are mixed to prepare a mixed solution;

[0016] The mixed solution is formed into a film and then annealed to prepare the hole transport layer.

[0017] In one embodiment, the annealing conditions include: the annealing conditions include: the temperature is 90° C. to 130° C., and the time is 5 min to 40 min.

[0018] In one embodiment, the solvent comprises one or more of methanol, ethanol, isopropanol, chlorobenzene and toluene; and / or

[0019] The film forming method is spin coating, and the spin coating conditions include: a rotation speed of 4000 r / min~6000 r / min, an acceleration of 2000 r / min^2~5000 r / min^2, and a time of 20s~50s.

[0020] The third aspect of the present application provides an all-perovskite tandem cell, including the narrow-bandgap perovskite cell described in the first aspect.

[0021] The fourth aspect of the present application provides an electrical device, comprising the narrow bandgap perovskite cell described in the first aspect or the full perovskite stacked cell described in the third aspect.

[0022] The above-mentioned narrow-bandgap perovskite cell uses N4,N4`-di(4-vinylphenyl)-N4,N4`-di-1-naphthylbiphenyl-4,4`-diamine (VNPB) mixed with self-assembled monolayer molecular material (SAM) as the hole transport layer on the basis of the narrow-bandgap perovskite layer. It has a more suitable energy band matching relationship with the narrow-bandgap perovskite, thereby effectively improving the photoelectric conversion efficiency of the device. At the same time, VNPB can undergo cross-linking and curing during the annealing process, has better stability, and good moisture resistance, which is conducive to isolating water vapor from damaging the perovskite layer. In addition, it can also avoid the degradation-promoting effect of acidic hole transport layer materials such as PEDOT:PSS on perovskite, which can comprehensively improve the stability of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the energy level matching relationship between various hole transport layers and narrow bandgap perovskites. DETAILED DESCRIPTION

[0024] The narrow bandgap perovskite cell and its preparation method, all-perovskite stacked cell, and electrical device of the present application are further described in detail below in conjunction with specific embodiments. The present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0026] The optional scope of the terms "and / or", "or / and", and "and / or" used in this article includes any one of two or more related listed items, and also includes any and all combinations of the related listed items, said any and all combinations include any combination of any two related listed items, any more related listed items, or all related listed items.

[0027] As used herein, "one or more" refers to any one, any two, or any two or more of the listed items.

[0028] In this application, "first aspect", "second aspect", "third aspect", "fourth aspect", etc. are used only for descriptive purposes and cannot be understood as indicating or implying relative importance or quantity, nor can they be understood as implicitly indicating the importance or quantity of the indicated technical features. Moreover, "first", "second", "third", "fourth", etc. only serve the purpose of non-exhaustive enumeration and description, and it should be understood that they do not constitute a closed limitation on quantity.

[0029] In the present application, the technical features described in an open manner include closed technical solutions composed of the listed features, and also include open technical solutions containing the listed features.

[0030] In this application, when it comes to numerical ranges, unless otherwise specified, the above numerical ranges are deemed to be continuous and include the minimum and maximum values ​​of the range, as well as each value between such minimum and maximum values. Further, when a range refers to an integer, each integer between the minimum and maximum values ​​of the range is included. In addition, when multiple ranges are provided to describe features or characteristics, the ranges can be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges included therein.

[0031] The percentage contents involved in this application, unless otherwise specified, refer to mass percentage for solid-liquid mixing and solid-solid mixing, and refer to volume percentage for liquid-liquid mixing.

[0032] The percentage concentrations mentioned in this application, unless otherwise specified, refer to the final concentration, which refers to the percentage of the added component in the system after the addition of the component.

[0033] The temperature parameters in this application, unless otherwise specified, allow for both constant temperature treatment and treatment within a certain temperature range. The constant temperature treatment allows the temperature to fluctuate within the accuracy range of instrument control.

[0034] The room temperature in this application generally refers to 4°C~30°C, preferably 20±5°C.

[0035] Some examples of the present application provide a narrow bandgap perovskite cell, comprising a first electrode layer, a functional layer, and a second electrode layer which are stacked; the functional layer comprises a hole transport layer and a narrow bandgap perovskite layer which are stacked; the material of the hole transport layer comprises N4,N4`-di(4-vinylphenyl)-N4,N4`-di-1-naphthylbiphenyl-4,4`-diamine (VNPB) and a self-assembled monolayer molecular material.

[0036] It can be understood that the chemical structure of N4,N4`-di(4-vinylphenyl)-N4,N4`-di-1-naphthylbiphenyl-4,4`-diamine (VNPB) is as follows:

[0037]

[0038] Without limitation, N4,N4`-di(4-vinylphenyl)-N4,N4`-di-1-naphthylbiphenyl-4,4`-diamine (VNPB) mixed with self-assembled monolayer molecular material (SAM) is used as the hole transport layer, and the matching relationship between VNPB and narrow bandgap perovskite is as follows: Figure 1 As shown, by comparing with the traditional hole transport layer materials NiOx and PEDOT:PSS, it can be seen that the hole transport layer of the present application has an energy level that is more matched with the narrow bandgap perovskite.

[0039] In some examples, the molar mass ratio of the molecular self-assembled monolayer molecular material to the N4, N4`-di(4-vinylphenyl)-N4, N4`-di-1-naphthylbiphenyl-4, 4`-diamine is 1:2 to 2:1. Specifically, the molar mass ratio of the molecular self-assembled monolayer molecular material to the N4, N4`-di(4-vinylphenyl)-N4, N4`-di-1-naphthylbiphenyl-4, 4`-diamine includes but is not limited to: 1:2, 1:1.5, 1:1, 1.5:1, 2:1 or a range between any two of the foregoing.

[0040] In some examples, the self-assembled monolayer molecular material includes one or more of MeO-2PACz, 2PACz, 4PACz and Me-4PACz.

[0041] In some examples, the bandgap of the narrow bandgap perovskite layer is in the range of 1.1 eV to 1.55 eV. Specifically, the bandgap of the narrow bandgap perovskite layer includes but is not limited to: 1.1 eV, 1.15 eV, 1.2 eV, 1.25 eV, 1.3 eV, 1.35 eV, 1.4 eV, 1.45 eV, 1.55 eV or a range between any two of the foregoing.

[0042] In some examples, the narrow bandgap perovskite layer includes a material having a general formula of Cs x FA y MA (1-x-y) Sn z Pb (1-z) (I r Br (1-r) )3, where 1≥x≥0, 1≥y≥0, 1≥z≥0, 1≥r≥0.

[0043] Without limitation, the narrow bandgap perovskite cell comprises a first electrode layer (transparent electrode layer, such as ITO transparent conductive glass), a hole transport layer, a narrow bandgap perovskite layer, an interface passivation layer (such as PCBM), an electron transport layer (such as BCP) and a second conductive layer (metal electrode layer, such as a copper layer) stacked in sequence.

[0044] Some other examples of the present application provide a method for preparing the narrow bandgap perovskite cell as described above, comprising the following steps:

[0045] Preparing the functional layer on the surface of the first electrode layer;

[0046] Preparing the second electrode layer on the surface of the functional layer;

[0047] The process of preparing the functional layer includes the step of preparing the hole transport layer, and the step includes:

[0048] The N4,N4`-di(4-vinylphenyl)-N4,N4`-di-1-naphthylbiphenyl-4,4`-diamine, the self-assembled monolayer molecular material and the solvent are mixed to prepare a mixed solution;

[0049] The mixed solution is formed into a film and then annealed to prepare the hole transport layer.

[0050] Without limitation, the step of preparing the hole transport layer is performed in a nitrogen atmosphere.

[0051] In some examples, the annealing conditions include: a temperature of 90°C to 130°C and a time of 5 min to 40 min. Specifically, the temperature includes but is not limited to: 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 127°C, 130°C or a range between any two of the foregoing; the time includes but is not limited to: 5 min, 10 min, 13 min, 15 min, 17 min, 20 min, 25 min, 30 min, 35 min, 40 min or a range between any two of the foregoing.

[0052] In some examples, the solvent includes one or more of methanol, ethanol, isopropanol, chlorobenzene, and toluene.

[0053] In some of the examples, the film forming method is spin coating, and the spin coating conditions include: a rotation speed of 4000r / min~6000r / min, an acceleration of 2000r / min^2~5000 r / min^2, and a time of 20s~50s. Specifically, the rotation speed includes but is not limited to: 4000r / min, 4500r / min, 4800r / min, 5000r / min, 5500r / min, 6000r / min or a range between any two of the foregoing; the acceleration includes but is not limited to: 2000r / min^2, 2500r / min^2, 3000r / min^2, 3500r / min^2, 4000r / min^2, 4500r / min^2, 5000r / min^2 or a range between any two of the foregoing; the time includes but is not limited to: 20s, 25s, 30s, 32s, 35s, 40s, 45s, 50s or a range between any two of the foregoing.

[0054] Some other examples of the present application provide an all-perovskite tandem cell, including the narrow bandgap perovskite cell as described above.

[0055] Some other examples of the present application provide an electrical device, comprising the narrow bandgap perovskite cell as described above or the all-perovskite stacked cell as described above.

[0056] For experimental parameters not specified in the following specific embodiments, reference is made to the instructions given in the present application document, and reference may also be made to experimental manuals in the art or other experimental methods known in the art, or to experimental conditions recommended by manufacturers.

[0057] The raw materials and reagents involved in the following specific examples can be obtained from commercial sources, or can be prepared by those skilled in the art according to known methods.

[0058] Example 1

[0059] This embodiment is a narrow bandgap perovskite cell, and its preparation process is as follows:

[0060] (1) After wiping the ITO conductive glass with a cleaning agent, place it on a polytetrafluoroethylene glass rack and clean it with deionized water, acetone and isopropanol for 15 minutes each. After cleaning, blow dry the substrate with a nitrogen gun and place it in a UV ozone cleaning machine for 20 minutes. After cleaning, place it in a receiving container for standby use.

[0061] (2) The hole transport layer was prepared by spin coating. Specifically, a pre-prepared VNPB (SAM) solution was sucked with a pipette in a glove box filled with nitrogen. The solution preparation process was as follows: VNPB and MeO-2PACZ self-assembled monomolecular material powders were weighed in a molar mass ratio of 1:1 on a precision balance, and methanol solvent and magnet were added to stir and fully dissolve them. Subsequently, the solution was drop-coated on the substrate obtained in step (1) placed on a spin coater, and the spin coating program was started. The spin coating program was a rotation speed of 4800 r / min, an acceleration of 2500 r / min^2, and a time of 32 seconds. After the spin coating was completed, the substrate was placed on a hot stage at 125°C and annealed for 30 minutes to obtain a hole transport layer with a thickness of about 15 nm.

[0062] (3) A perovskite layer is prepared on the hole transport layer prepared in step (2). The components of the perovskite precursor solution are as follows: (Cs 0.025 FA 0.45 MA 0.525 )(Sn 0.5 Pb 0.5 )(I 0.975 Br 0.025 )3 is configured, and the configured perovskite precursor droplets are applied to the hole transport layer with a pipette, and the spin coating program is started. The spin coating program is a two-step spin coating. The first step is a rotation speed of 1000r / min, an acceleration of 1000r / min^2, and a duration of 8 seconds. The second step is a rotation speed of 4800r / min, an acceleration of 2500r / min^2, and a duration of 30 seconds. At the eighth second from the end, 200μL of anti-solvent chlorobenzene is added to promote perovskite nucleation, and then it is placed on a hot stage at 95℃ for annealing for 15 minutes. After annealing, it is removed and allowed to cool naturally to obtain a perovskite layer with a thickness of about 600μm.

[0063] (4) According to the conventional method, a PCBM layer and a BCP layer are sequentially prepared by spin coating on the perovskite layer, wherein the thickness of the PCBM layer is about 20 nm and the thickness of the BCP layer is about 7 nm. Then, the layers are transferred to a vacuum thermal evaporation deposition machine and heated for 10 min. -5 Under a vacuum degree of 1.5 Pa, 100 nm of metallic copper was evaporated thereon.

[0064] Example 2

[0065] This embodiment is a narrow bandgap perovskite battery, and its preparation process is the same as that of Example 1, with the main difference being that the molar mass ratio of VNPB and MeO-2PACZ self-assembled monomolecular materials is 2:1.

[0066] Example 3

[0067] This embodiment is a narrow bandgap perovskite battery, and its preparation process is the same as that of Example 1, with the main difference being that the molar mass ratio of VNPB and MeO-2PACZ self-assembled monomolecular materials is 1:2.

[0068] Comparative Example 1

[0069] This comparative example is a narrow bandgap perovskite cell, and its preparation process is the same as that of Example 1, the main difference being that the MeO-2PACZ self-assembled monomolecular material is not used.

[0070] Comparative Example 2

[0071] This comparative example is a narrow bandgap perovskite cell, and its preparation process is the same as that of Example 1, with the main difference being that traditional NiOx is used as the hole transport layer, and the annealing temperature of the corresponding step is 125°C.

[0072] Comparative Example 3

[0073] This comparative example is a narrow bandgap perovskite cell, and its preparation process is the same as that of Example 1, with the main difference being that traditional PEDOT:PSS is used as the hole transport layer, and the annealing temperature of the corresponding step is 100°C.

[0074] Test example:

[0075] Test method: The evaporated narrow-bandgap perovskite cell was connected to a solar simulator, a raw meter, and an efficiency test system to test its photoelectric conversion performance. The test conditions were: test in a glove box, the glove box temperature was 25°C, the water and oxygen content was less than 0.01ppm, tested by a Keithley 2400 source meter, the light source was AM1.5G, 100mW / cm 2 The light source intensity is calibrated by a standard silicon battery, the voltage test range is -0.1V-2.1V, and the delay time is 50ms.

[0076] The test results are shown in Table 1 below:

[0077] Table 1

[0078]

[0079] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0080] The above-described embodiments only express several implementation methods of the present application, which is convenient for understanding the technical solution of the present application in detail, but it cannot be understood as limiting the scope of protection of the patent application. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the scope of protection of the present application. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning or limited experiments on the basis of the technical solutions provided in the present application are all within the scope of protection of the claims attached to the present application. Therefore, the scope of protection of the patent of this application shall be based on the content of the attached claims, and the description can be used to interpret the content of the claims.

Claims

1. A narrow bandgap perovskite cell, characterized in that: It comprises a first electrode layer, a functional layer and a second electrode layer which are stacked; the functional layer comprises a hole transport layer and a narrow bandgap perovskite layer which are stacked; the material of the hole transport layer comprises a mixture of N4,N4`-di(4-vinylphenyl)-N4,N4`-di-1-naphthylbiphenyl-4,4`-diamine and a self-assembled monolayer molecular material; The molar mass ratio of the self-assembled monolayer molecular material to the N4,N4`-di(4-vinylphenyl)-N4,N4`-di-1-naphthylbiphenyl-4,4`-diamine is 1:1; the self-assembled monolayer molecular material is MeO-2PACz.

2. The narrow bandgap perovskite cell according to claim 1, characterized in that: The narrow bandgap perovskite layer has a bandgap range of 1.1 eV to 1.55 eV.

3. The narrow bandgap perovskite cell according to claim 2, characterized in that: The narrow bandgap perovskite layer includes a material of the general formula Cs x FA y MA (1-x-y) Sn z Pb (1-z) (I r Br (1-r) )3, where 1≥x≥0, 1≥y≥0, 1≥z≥0, 1≥r≥0.

4. The method for preparing a narrow bandgap perovskite battery according to any one of claims 1 to 3, characterized in that: The steps include: Preparing the functional layer on the surface of the first electrode layer; Preparing the second electrode layer on the surface of the functional layer; The process of preparing the functional layer includes the step of preparing the hole transport layer, and the step includes: The N4,N4`-di(4-vinylphenyl)-N4,N4`-di-1-naphthylbiphenyl-4,4`-diamine, the self-assembled monolayer molecular material and the solvent are mixed to prepare a mixed solution; The mixed solution is formed into a film and then annealed to prepare the hole transport layer.

5. The method for preparing a narrow bandgap perovskite cell according to claim 4, characterized in that: The annealing conditions include: temperature of 90°C to 130°C and time of 5min to 40min.

6. The method for preparing a narrow bandgap perovskite cell according to claim 4 or 5, characterized in that: The solvent includes one or more of methanol, ethanol, isopropanol, chlorobenzene and toluene.

7. The method for preparing a narrow bandgap perovskite cell according to claim 4 or 5, characterized in that: The film forming method is spin coating, and the spin coating conditions include: a rotation speed of 4000r / min~6000r / min, an acceleration of 2000r / min^2~5000r / min^2, and a time of 20s~50s.

8. A full perovskite tandem battery, characterized in that: A narrow bandgap perovskite cell comprising the method described in any one of claims 1 to 3.

9. An electrical device, characterized in that: It includes the narrow bandgap perovskite cell according to any one of claims 1 to 3 or the all-perovskite stacked cell according to claim 8.

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