Wide-band-gap perovskite solar cell based on amide-based additive and preparation method of wide-band-gap perovskite solar cell

Abstract

The invention discloses a wide-band-gap perovskite solar cell based on an amide-based additive and a preparation method of the wide-band-gap perovskite solar cell, and belongs to the technical field of perovskite solar cells. The amido additive has a structural general formula (I) # imgabs0 #. Wherein R comprises a carbon-oxygen double bond, a carbon-nitrogen double bond, a carbon-sulfur double bond, a sulfur-oxygen double bond and a phosphorus-oxygen double bond; r1 and R2 comprise C0-C6 straight-chain alkyl, alkylamine / ammonium salt, halogenated hydrocarbon, cycloalkyl, cycloalkenyl, aromatic ring and heterocyclic compound. Benefited from the amide-based additive provided by the invention, the crystallization film forming quality of broadband gap perovskite precursors with different components is improved, so that the performance of the broadband gap perovskite solar cell is improved. The wide-band-gap perovskite absorption layer based on the amide-based additive can be prepared through an anti-solvent method or a vacuum flash evaporation method, and has good process flexibility.

Description

Technical Field

[0001] The present invention belongs to the field of perovskite solar cells, and particularly relates to a wide-bandgap perovskite solar cell based on an amide-based additive and a preparation method thereof. Background Art

[0002] In recent years, perovskite solar cells have developed very rapidly. Due to the ability of perovskite materials to have adjustable bandgaps, their application in tandem solar cells at both ends has exceeded the limit of single-junction solar cells. Therefore, both the industrial and academic communities have shown great interest in the field of perovskite tandem. In the development process of perovskite tandem solar cells, it is crucial to develop highly efficient and stable wide-bandgap perovskite sub-cells. Since there is a relatively large amount of bromide ions in the wide-bandgap perovskite component, the crystallization rate of the bromine-rich intermediate phase is fast during the crystallization process, resulting in iodine ions leaving vacancy defects after crystallization diffusion, leading to the formation of non-radiative recombination channels and an increase in defect density, causing problems such as large open-circuit voltage losses and phase segregation under light in wide-bandgap perovskite solar cells. Therefore, improving the crystallization quality of wide-bandgap perovskite thin films is the key to further improving the efficiency and stability of wide-bandgap perovskite solar cells.

[0003] In order to reduce the defect state density and non-radiative recombination loss of wide-bandgap perovskite thin films, various additives have been used to regulate the crystallization process in perovskite precursor solutions, thereby improving the crystallization quality of perovskite thin films. However, existing additives are mostly effective for specific components of perovskite precursors and have differences in applicability to wide-bandgap perovskites with different components and different preparation methods. Therefore, there is an urgent need in the field of wide-bandgap perovskite solar cells to develop a universal additive that has a crystallization regulation effect on wide-bandgap perovskites with different components and different preparation methods. Summary of the Invention

[0004] The object of the present invention is to overcome the above-mentioned deficiencies existing in the prior art and propose a wide-bandgap perovskite solar cell based on an amide-based additive and a preparation method thereof.

[0005] To achieve the object of the present invention, we propose to use an amide-based additive to improve the crystallization quality of wide-bandgap perovskite thin films and reduce the defect state density, thereby improving the efficiency and stability of wide-bandgap perovskite solar cells. This additive can act on the perovskite bulk phase by introducing it into the perovskite precursor solution, introducing it at the perovskite bottom interface, or coating it on the surface of the perovskite absorption layer as a passivation layer. In addition, this additive has good universality for wide-bandgap perovskites with different components and different preparation methods.

[0006] The technical solution of the present invention:

[0007] In the first aspect, the present invention provides an amide-based additive with high universality.

[0008] The amide group additive includes at least one of the compounds shown in Formula I:

[0009] wherein R includes a carbon-containing group, a nitrogen-containing group, an oxygen-containing group, a sulfur-containing group, and a phosphorus-containing group; R 1 and R 2 each independently includes at least one of an unsubstituted or substituted C 0 -C 10 alkyl group, an unsubstituted or substituted C 0 -C 10 alkenyl group, and an unsubstituted or substituted aryl group, and the substituents include at least one of a nitrogen-containing group, an oxygen-containing group, a sulfur-containing group, a phosphorus-containing group, and a halogen-containing group.

[0010] The nitrogen-containing group includes at least one of an amino group, a quaternary ammonium salt, N,N-dimethyl, azo, pyridine, nitro, amidino, amide, imide, cyano, and isocyanate group.

[0011] The oxygen-containing group includes at least one of a carbonyl group, a hydroxyl group, an ether oxygen, a carboxyl group, an acid anhydride, an ester group, an aldehyde group, a ketone group, and an acyl halide group.

[0012] The sulfur-containing group includes at least one of a thiol group, a thioether group, a sulfoxide group, a sulfone group, a sulfonyl group, a sulfinyl group, and a sulfonic acid group.

[0013] The phosphorus-containing group includes at least one of a phosphoric acid group, a phosphoryl group, a phosphorous acid group, a phosphate ester group, and a phosphino group.

[0014] Furthermore, R includes a carbon-oxygen double bond, a carbon-nitrogen double bond, a carbon-sulfur double bond, a sulfur-oxygen double bond, and a phosphorus-oxygen double bond.

[0015] Furthermore, R 1 and R 2 include a straight-chain alkyl group of C 0 -C 6 alkylamine / ammonium salt, halogenated hydrocarbon, cycloalkyl group, cycloalkenyl group, aromatic ring, and heterocyclic compound.

[0016] In a second aspect, the present invention provides a method for applying an amide group additive in a wide-bandgap perovskite solar cell.

[0017] The method for applying the amide group additive in a wide-bandgap perovskite solar cell is one or more of adding one or more additives to a wide-bandgap perovskite precursor solution, coating on the buried bottom interface of the perovskite absorption layer, and coating on the surface of the perovskite absorption layer as a passivation layer.

[0018] The dosage of the additive is at least one of 0.1 mol% - 25 mol% of the amount of the perovskite precursor, and the solvent is at least one of organic solvents such as N,N-dimethylformamide, dimethyl sulfoxide, methylamine / alcohol mixed solution, acetonitrile, 2-methoxyethanol, etc.; or at least one of gases such as methylamine, formamidine, etc.; or at least one of ionic liquids such as methylammonium acetate, methylammonium formate, formamidinium acetate.

[0019] The stirring temperature of the perovskite precursor solution containing the additive is at least one of 30 - 70 °C.

[0020] The concentration of the additive applied to the buried bottom interface is at least one of 0.1 mg / mL - 10 mg / mL, and the solvent is at least one of amide solvents, sulfone / sulfoxide solvents, ester solvents, hydrocarbon / halohydrocarbon solvents, alcohol solvents, ketone solvents, ether solvents, aromatic hydrocarbons, such as N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, γ-butyrolactone, acetonitrile, chlorobenzene, toluene, isopropanol.

[0021] The concentration of the additive applied to the passivation layer is 0.01 mg / mL - 10 mg / mL, and the solvent is at least one of organic solvents such as isopropanol, chlorobenzene, toluene, dichloromethane that do not dissolve the perovskite material.

[0022] In a third aspect, the present invention provides a method for preparing a wide-bandgap perovskite solar cell based on an amide group additive.

[0023] The basic structure of the wide-bandgap perovskite solar cell based on the amide group additive (as Figure 1 shown) includes a transparent conductive substrate, a nickel oxide hole transport layer, a self-assembled (SAM) layer, a buried bottom interface layer, a perovskite absorption layer, a passivation layer, an electron transport layer, a hole blocking layer, and a metal electrode.

[0024] Furthermore, the amide group additive can be used in one of the buried bottom interface layer, the perovskite absorption layer, and the passivation layer, or can also be applied to two or three of the buried bottom interface layer, the perovskite absorption layer, and the passivation layer at the same time. The preparation method described in the present invention includes all the above situations, and one of them can be selected according to the situation for application.

[0025] The transparent conductive substrate is indium tin oxide (ITO) or fluorine-doped tin oxide (FTO) conductive glass;

[0026] The hole transport layer material is nickel oxide, and the SAM material is at least one of carboxylic acid, phosphoric acid, silicic acid, boric acid-based monomers or polymer carbazole compounds;

[0027] The perovskite absorption layer can be at least one of inorganic perovskite materials, organic perovskite materials, organic-inorganic hybrid perovskite materials, etc. Taking the perovskite material with an organic-inorganic hybrid ABX 3 structure as an example, where the A-site cation is at least one of lithium, sodium, potassium, rubidium, cesium, amino, amidino, guanidine compounds, and the B-site cation is Pb 2+ , Sn 2+ , Ge 2+ , Sb 2+ , Bi 3+ and other at least one of the main group elements in the fourth, fifth, and sixth groups, and the X-site anion is I - , Cl - , Br - , SCN - , OCN - and other at least one of halogens or pseudohalogens. The perovskite absorption layer is a wide-bandgap perovskite thin film with a bandgap of 1.6 eV–2.9 eV and a thickness of 300-600 nm;

[0028] The passivation layer is an amide-based additive or one or more of monoammonium or diammonium organic / inorganic halides;

[0029] The electron transport layer material is a fullerene derivative (PCBM) or fullerene (C 60 ), and the hole blocking layer material is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) or tin oxide.

[0030] The metal electrode can be at least one of various metals such as but not limited to Au, Ag, Al, Cu, Ti, etc.

[0031] The preparation method of the wide-bandgap perovskite solar cell based on the amide group additive is as follows:

[0032] (1) Prepare a nickel oxide hole transport layer on ITO or FTO transparent conductive glass;

[0033] (2) Prepare a SAM layer on the above nickel oxide hole transport layer in a glove box filled with nitrogen;

[0034] (3) Prepare a buried interface based on one or more amide group additives on the hole transport layer;

[0035] (4) Prepare a wide-bandgap perovskite thin film on the SAM layer including the buried interface above;

[0036] Furthermore, the wide-bandgap perovskite thin film can be prepared by an anti-solvent method or a vacuum flash evaporation method;

[0037] Furthermore, in the anti-solvent method, an anti-solvent is used to extract and prepare a perovskite thin film from a perovskite precursor containing an additive, and then further annealing treatment is performed; the anti-solvent includes one or more of isopropyl alcohol, ethyl acetate, methyl acetate, diethyl ether, anisole, toluene, and chlorobenzene.

[0038] Furthermore, in the vacuum flash evaporation method, by utilizing the different saturated vapor pressures of organic solvents in the perovskite precursor containing an additive, the environmental pressure and negative pressure time of the perovskite precursor liquid film environment are controlled to prepare a perovskite thin film, and then further annealing treatment is performed;

[0039] Furthermore, the environmental pressure is one or more conditions among 1×10 -5 Pa - 1×10 5 Pa;

[0040] Furthermore, the negative pressure time is one or more conditions among 1 s - 180 s.

[0041] (5) A passivation layer is prepared on the perovskite absorption layer;

[0042] Furthermore, the nickel oxide transport layer, SAM layer, buried bottom interface layer, perovskite absorption layer, and passivation layer can be prepared by one method among spin coating, blade coating, slot die coating, spraying, and inkjet printing.

[0043] (6) An electron transport layer is prepared on the perovskite absorption layer containing the passivation layer;

[0044] (7) A hole blocking layer is prepared on the electron transport layer;

[0045] (8) A metal electrode is deposited on the hole blocking layer.

[0046] Advantages and positive effects of the present invention: The additive with the structural general formula (I) proposed by the present invention, . Among them, R, R 1 and R 2 can be nucleophilic groups or electrophilic groups, R, R 1 and R 2It can interact with free anions or cations in the perovskite precursor, such as forming hydrogen bonds, ionic bonds or covalent bonds, thereby increasing the ionic migration energy barrier, inhibiting ionic migration during the crystallization process of perovskite materials, and simultaneously compensating for the vacancies in the perovskite lattice that cannot be solved by conventional annealing processes. Thanks to the additive according to the present invention, the crystallization process of wide-bandgap perovskite can be effectively controlled, the defects inside, on the surface and at the grain boundaries of the perovskite absorption layer can be adjusted, and an oriented dipole effect is generated on the surface of the perovskite absorption layer, effectively promoting charge separation and transport at the interface. The present invention effectively solves the problems of poor crystallization quality, many defects and unsatisfactory environmental stability of the perovskite absorption layer caused by the too fast crystallization rate of a large number of bromide ion crystal nuclei in the wide-bandgap perovskite precursor, further improves the performance of the wide-bandgap perovskite device, and lays a foundation for the application of transparent single-junction solar cells or high-efficiency multi-junction stacked solar cells and their corresponding large-area solar cells and other optoelectronic devices such as light-emitting diodes, photodetectors, and lasers. At the same time, the amide-based additive proposed by the present invention has good universality and can improve the performance and stability in wide-bandgap perovskites with different components and different preparation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a schematic structural diagram of the perovskite solar cell device in the present invention;

[0049] Figure 2 It is the current density-voltage curve diagram of Embodiment 1, Embodiment 2, Embodiment 3, Comparative Example 1 and Comparative Example 2 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0051] In order to make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0052] Embodiment 1

[0053] (1) ITO / glass was used as the substrate, and it was ultrasonically cleaned with a cleaning agent, deionized water, acetone, and isopropanol and then treated with ozone for 20 min.

[0054] (2) An aqueous solution of nickel oxide with a concentration of 20 mg / mL was spin-coated at a speed of 4000 rpm for 30 s and annealed at 100 °C for 20 min to prepare a nickel oxide hole transport layer.

[0055] (3) A SAM layer was prepared by spin - coating a 1 mol% Me - 4PACz ethanol solution on the nickel oxide hole - transporting layer at a speed of 3000 rpm for 30 s and annealing at 100 °C for 10 min.

[0056] (4) A wide - bandgap perovskite absorption layer was prepared on the hole - transporting layer. The perovskite raw materials were weighed according to the molar ratio, and its powder and additive P1 were simultaneously dissolved in a mixed solvent of DMF and DMSO and stirred overnight to obtain a yellow - clear 1.2 mol / L perovskite precursor solution. 50 μL of the solution was dropped onto the conductive substrate covered with the hole - transporting layer, spin - coated at a speed of 5000 rpm for 50 s, and 400 μL of ethyl acetate antisolvent was dropped at the 40th s, and then annealed at 100 °C for 15 min to obtain a wide - bandgap perovskite thin film.

[0057] (5) A 0.5 mg / mL ethane - 1,2 - diammonium iodide (EDAI 2 ) isopropanol solution was used to passivate the wide - bandgap perovskite absorption layer, spin - coated at a speed of 5000 rpm for 30 s, and then annealed at 100 °C for 5 min to prepare the passivation layer.

[0058] (6) An electron - transporting layer of C 60 was prepared on the passivation layer. The above - mentioned thin film was transferred to a vacuum evaporation chamber, evacuated to 3×10 -4 Pa, and then 20 nm was deposited.

[0059] (7) In the same vacuum chamber and vacuum degree as in (6), BCP was thermally evaporated and deposited onto the C 60 thin film, and the thickness of the BCP thin film was 10 nm.

[0060] (8) In the same vacuum chamber and vacuum degree as in (6), 130 nm of Cu was deposited as the metal electrode.

[0061] Figure 2 It is the current density - voltage curve diagram of the perovskite solar cell shown in Example 1.

[0062] Example 2

[0063] The specific preparation method of this example is similar to the preparation method in Example 1. The difference is that the vacuum flash evaporation method was used when preparing the perovskite absorption layer in step (4). The preparation method of the perovskite absorption layer in this example is as follows:

[0064] A wide - bandgap perovskite absorption layer was prepared on the hole - transporting layer. The perovskite raw materials were weighed according to the molar ratio, and its powder and additive P1 Stir overnight in a mixed solvent of DMF and DMSO to obtain a clear yellow 1.2 mol / L perovskite precursor. Take 50 μL of the solution and drop it onto a conductive substrate covered with a hole transport layer, spin-coat it at 3000 rpm for 30 s, place the substrate in a vacuum flash evaporation chamber and quickly pump it down to 1×10 -2 Pa, hold for 1 min, take out the substrate, and anneal it at 100 °C for 15 min to obtain a wide-bandgap perovskite thin film.

[0065] Figure 2 It is the current density-voltage curve graph of the perovskite solar cell shown in Example 2.

[0066] Example 3

[0067] The specific preparation method of this example is similar to that in Example 2. The difference is that an additional buried interface treatment step is added between step (3) and step (4). The specific method is as follows:

[0068] Dissolve P1 in IPA solution and stir until clear. Take 80 μL of the solution and drop it onto a conductive substrate covered with a hole transport layer, spin-coat it at 4000 rpm for 30 s, and anneal it at 100 °C for 5 min to obtain a buried interface.

[0069] Figure 2 It is the current density-voltage curve graph of the perovskite solar cell shown in Example 3.

[0070] Example 4

[0071] The specific preparation method of this example is similar to that in Example 1. The difference is that the perovskite absorption layer is prepared in step (4). The preparation method of the perovskite absorption layer in this example is as follows:

[0072] Prepare a wide-bandgap perovskite absorption layer on the hole transport layer. Weigh the perovskite raw materials according to the molar ratio, and mix its powder with the additive P2 and dissolve them simultaneously in a mixed solvent of DMF and DMSO, stir overnight to obtain a clear yellow 1.2 mol / L perovskite precursor solution. Take 50 μL of the solution and drop it onto a conductive substrate covered with a hole transport layer, spin-coat it at 5000 rpm for 50 s, and add 400 μL of anisole antisolvent at the 40th second to obtain it, and anneal it at 100 °C for 15 min to obtain a wide-bandgap perovskite thin film.

[0073] Example 5

[0074] The specific preparation method of this example is similar to that in Example 2, except that the perovskite absorption layer is prepared in step (4). The preparation method of the perovskite absorption layer in this example is as follows:

[0075] A wide-bandgap perovskite absorption layer is prepared on the hole transport layer. The perovskite raw materials are weighed according to the molar ratio, and its powder and additive P2 are simultaneously dissolved in a mixed solvent of DMF and DMSO and stirred overnight to obtain a yellow and clear 1.2 mol / L perovskite precursor. Take 50 μL of the solution and drop it on the conductive substrate covered with the hole transport layer, spin-coat it at a speed of 3000 rpm for 30 s, put the substrate into the vacuum flash evaporation chamber and quickly pump it to 1×10 -2 Pa, hold for 1 min, take out the substrate, and anneal it at 100 °C for 15 min to obtain a wide-bandgap perovskite thin film.

[0076] Example 6

[0077] The specific preparation method of this example is similar to that in Example 1, except that the perovskite absorption layer is prepared in step (4). The preparation method of the perovskite absorption layer in this example is as follows:

[0078] A wide-bandgap perovskite absorption layer is prepared on the hole transport layer. The perovskite raw materials are weighed according to the molar ratio, and its powder and additive P3 are simultaneously dissolved in a mixed solvent of DMF and DMSO and stirred overnight to obtain a yellow and clear 1.2 mol / L perovskite precursor solution. Take 50 μL of the solution and drop it on the conductive substrate covered with the hole transport layer, spin-coat it at a speed of 5000 rpm for 50 s and add 400 μL of anisole antisolvent at the 40th s, and anneal it at 100 °C for 15 min to obtain a wide-bandgap perovskite thin film.

[0079] Example 7

[0080] The specific preparation method of this example is similar to that in Example 1, except that the perovskite absorption layer is prepared in step (4). The preparation method of the perovskite absorption layer in this example is as follows:

[0081] A wide-bandgap perovskite absorption layer is prepared on the hole transport layer. The perovskite raw materials are weighed according to the molar ratio, and its powder and additive P3 are simultaneously dissolved in a mixed solvent of DMF and DMSO and stirred overnight to obtain a yellow and clear 1.2 mol / L perovskite precursor. Take 50 μL of the solution and drop it on the conductive substrate covered with the hole transport layer, spin-coat it at a speed of 3000 rpm for 30 s, put the substrate into the vacuum flash evaporation chamber and quickly pump it to 1×10 -2 At a pressure of Pa, keep it for 1 min, take out the substrate, and anneal it at 100 °C for 15 min to obtain a wide-bandgap perovskite thin film.

[0082] Comparative Example 1

[0083] The specific preparation method of this example is similar to that of Example 1, except that in step (4), a perovskite absorption layer is prepared. The preparation method of the perovskite absorption layer in this example is as follows:

[0084] Prepare a wide-bandgap perovskite absorption layer on the hole transport layer. Weigh the perovskite raw materials according to the molar ratio, dissolve its powder in a mixed solvent of DMF and DMSO, and stir overnight to obtain a yellow and clear 1.2 mol / L perovskite precursor. Take 50 μL of the solution and drop it on the conductive substrate covered with the hole transport layer, spin-coat it at a speed of 3000 rpm for 30 s, put the substrate into the vacuum flash evaporation chamber and quickly pump it to 1×10 -2 Pa, keep it for 1 min, take out the substrate, and anneal it at 100 °C for 15 min to obtain a wide-bandgap perovskite thin film.

[0085] Figure 2 It is the current density-voltage curve of the perovskite solar cell shown in Comparative Example 1.

[0086] Comparative Example 2

[0087] The specific preparation method of this example is similar to that of Example 1, except that in step (4), a perovskite absorption layer is prepared. The preparation method of the perovskite absorption layer in this example is as follows:

[0088] Prepare a wide-bandgap perovskite absorption layer on the hole transport layer. Weigh the perovskite raw materials according to the molar ratio, dissolve its powder in a mixed solvent of DMF and DMSO, and stir overnight to obtain a yellow and clear 1.2 mol / L perovskite precursor. Take 50 μL of the solution and drop it on the conductive substrate covered with the hole transport layer, spin-coat it at a speed of 3000 rpm for 30 s, put the substrate into the vacuum flash evaporation chamber and quickly pump it to 1×10 -2 Pa, keep it for 1 min, take out the substrate, and anneal it at 100 °C for 15 min to obtain a wide-bandgap perovskite thin film.

[0089] Figure 2 It is the current density-voltage curve of the perovskite solar cell shown in Comparative Example 2.

[0090] Table 1. Performance test results of the perovskite solar cells according to Examples 1 to 7 and Comparative Examples 1 and 2 <![CDATA[V OC (V)]]> <![CDATA[J SC (mA / cm 2 )]]> FF(%) PCE(%) Stability (h) Example 1 1.26 21.45 81.19 22.03 ＞500 Example 2 1.25 21.12 80.63 21.44 ＞500 Example 3 1.25 21.18 81.41 21.72 ＞500 Example 4 1.35 18.33 81.59 20.20 ＞500 Example 5 1.34 18.23 81.50 19.96 ＞500 Example 6 1.34 16.80 84.33 19.31 ＞500 Example 7 1.33 16.93 81.93 18.85 ＞500 Comparative Example 1 1.19 21.20 80.23 20.30 ＜500 Comparative Example 2 1.20 20.75 79.98 20.02 ＜500

[0091] Table 2. Perovskite precursor solution components and additive dosages according to Examples 1 to 7 and Comparative Examples 1 and 2 Chemical formula of perovskite material Dosage of additive Concentration of additive in perovskite precursor Example 1 <![CDATA[FA 0.83 Cs 0.17 (I 0.8 Br 0.2 ) 3 > Forchlorfenuron 0.5 mol% Example 2 <![CDATA[FA 0.83 Cs 0.17 (I 0.8 Br 0.2 ) 3 > Forchlorfenuron 0.5 mol% Example 3 <![CDATA[FA 0.83 Cs 0.17 (I 0.8 Br 0.2 ) 3 > Forchlorfenuron 2 mg / mL Example 4 <![CDATA[FA 0.8 Cs 0.2 (I 0.6 Br 0.4 ) 3 > Urea 0.75 mol% Example 5 <![CDATA[FA 0.8 Cs 0.2 (I 0.6 Br 0.4 ) 3 > Urea 0.75 mol% Example 6 <![CDATA[FA 0.8 Cs 0.2 (I 0.6 Br 0.4 ) 3 > 1-[4-(Trifluoromethyl)phenyl]biguanide hydrochloride 0.25 mol% Example 7 <![CDATA[FA 0.8 Cs 0.2 (I 0.6 Br 0.4 ) 3 > 1-[4-(Trifluoromethyl)phenyl]biguanide hydrochloride 0.25 mol% Comparative Example 1 <![CDATA[FA 0.83 Cs 0.17 (I 0.8 Br 0.2 ) 3 > None None Comparative Example 2 <![CDATA[FA 0.83 Cs 0.17 (I 0.8 Br 0.2 ) 3 > None None

[0092] As can be seen from Table 1, compared with Comparative Examples 1 and 2 without the addition of passivation additives, the open-circuit voltage (V OC )), fill factor (FF), and power conversion efficiency (PCE) of the perovskite solar cells in Examples 1 to 3 with the addition of passivation additives were all significantly improved. Thanks to the effective defect passivation of the passivation additives, the defect density of the perovskite layer was reduced, and non-radiative recombination was decreased, thus significantly improving the cell performance.

[0093] As can be seen from Tables 1 and 2, compared with Examples 1 to 3, Examples 4 and 5, and Examples 6 and 7, different amide-based additives can improve the cell performance when applied in different components and different preparation methods. It can be seen that the amide-based additives have universality in the application of wide-bandgap perovskite solar cells.

[0094] Those skilled in the art can easily understand that the above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wide bandgap perovskite solar cell based on amide additives and a preparation method thereof, characterized in that: The amide additive has the general structural formula (I) Wherein, R includes carbon-containing groups, nitrogen-containing groups, oxygen-containing groups, sulfur-containing groups, and phosphorus-containing groups; R1 and R2 each independently include unsubstituted or substituted C0-C 10 Alkyl, unsubstituted or substituted C0-C 10 At least one of an alkenyl group and an unsubstituted or substituted aryl group, and the substituent includes at least one of a nitrogen-containing group, an oxygen-containing group, a sulfur-containing group, a phosphorus-containing group and a halogen-containing group.

2. The amide additive according to claim 1, characterized in that R includes carbon-oxygen double bonds, carbon-nitrogen double bonds, carbon-sulfur double bonds, sulfur-oxygen double bonds, and phosphorus-oxygen double bonds.

3. The amide additive according to claim 1, characterized in that R1 and R2 include C0-C6 straight chain alkyl, alkylamine / ammonium salt, halogenated hydrocarbon, cycloalkyl, cycloalkenyl, aromatic ring, heterocyclic compound.

4. The amide additive according to claims 1-3, characterized in that The application method of amide additives in wide bandgap perovskite solar cells is to apply them in a wide bandgap perovskite precursor solution, coat them on the buried interface of the perovskite film, or coat them on the surface of the wide bandgap perovskite film, or to apply them to two or three of them at the same time.

5. The application method according to claim 4, wherein the amount of the perovskite precursor solution additive is at least one of 0.1 mol%-25 mol% of the amount of the perovskite precursor substance; the concentration of the additive coated on the buried interface is at least one of 0.1 mg / mL-10 mg / mL; the concentration of the additive coated on the surface of the wide bandgap perovskite film is 0.01 mg / mL-10 mg / mL.

6. The application method according to claim 4, characterized in that: The perovskite precursor solvent is at least one of organic solvents such as N,N-dimethylformamide, dimethyl sulfoxide, methylamine / alcohol mixed solution, acetonitrile, 2-methoxyethanol, etc.; or at least one of gases such as methylamine and formamidine; or at least one of ionic liquids such as methylamine acetate, methylamine formate, and formamidine acetate; the solvent on which the additive is coated on the buried interface is at least one of amide solvents, sulfone / sulfoxide solvents, ester solvents, hydrocarbon / halogenated hydrocarbon solvents, alcohol solvents, ketone solvents, ether solvents, and aromatic hydrocarbons; the solvent on which the additive is coated on the surface of the wide-bandgap perovskite film is at least one of organic solvents that do not dissolve the perovskite material, such as isopropanol, chlorobenzene, toluene, and dichloromethane.

7. A wide bandgap perovskite solar cell based on amide additives as claimed in claim 1, characterized in that: The battery comprises a transparent conductive substrate, a nickel oxide hole transport layer, a self-assembly layer, a buried interface layer, a perovskite absorption layer, a passivation layer, an electron transport layer, a hole blocking layer and a metal electrode from bottom to top, wherein the perovskite absorption layer is prepared by mixing the additive described in any one of claims 1 to 3 with a perovskite material.

8. The perovskite absorption layer according to claim 7, characterized in that Including at least one of inorganic perovskite materials, organic perovskite materials, organic-inorganic hybrid perovskite materials, etc., taking the organic-inorganic hybrid ABX3 structure perovskite material as an example, wherein the A-position cation is at least one of lithium, sodium, potassium, rubidium, cesium, amine, amidine, and guanidine compounds, and the B-position cation is Pb 2+ Sn 2+ ,Ge 2+ , Sb 2+ 、Bi 3+ At least one of the fourth, fifth and sixth main group elements is distributed equally, and the anion at the X position is I - , Cl - Br - 、SCN - 、OCN - At least one of isohalogen or pseudohalogen; the band gap of the perovskite material is 1.6eV-3.1 eV, the thickness is 300-600 nm, and the preparation method thereof can be an anti-solvent method or a vacuum flash evaporation method.

9. The perovskite absorption layer as claimed in any one of claims 4 to 7, and the nickel oxide hole transport layer, the main mounting layer, the buried interface layer, and the passivation layer, characterized in that: The film can be prepared by a method selected from spin coating, blade coating, slit coating, spray coating, and inkjet printing.

10. Any amide additive according to claim 1-8 and its application and preparation method, characterized in that: The amide-based additive can also be used in the perovskite absorption layer of single-junction wide-bandgap perovskite solar cells, perovskite tandem solar cells and their corresponding large-area solar cells.

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