Perovskite solar cell and manufacturing method

Abstract

The present invention provides a perovskite solar cell comprising at least an electrode, an electron transport layer, a hole transport layer, a perovskite layer, and a passivation layer. Herein, the passivation layer contains a passivation agent, and the passivation agent comprises an aza-fused dicyclic compound and / or an organic salt composed of an aza-fused dicyclic compound and an acid, wherein each condensation ring of the aza-fused dicyclic compound is independently a saturated ring, an unsaturated ring, or an aromatic ring of a pentagon or a hexagon, and the condensation ring of the aza-fused dicyclic compound contains 1 to 5 nitrogen atoms, and said condensation ring is a ring without substituents or a ring substituted by substituents having 1 to 3 carbon atoms.

Description

Technology Field

[0001] The present invention relates to a perovskite solar cell with improved stability and a method for manufacturing a perovskite solar cell. Background Technology

[0002] As the trend of slowing global warming and the construction of an ecological civilization gain greater attention, the diversification of energy sources and the development of green energy sources are also receiving increased interest. Among these, photovoltaic power generation, which converts solar energy into electricity, is widely used because it produces no carbon emissions during energy conversion and offers high flexibility in installation. However, current mainstream photovoltaic devices utilize silicon-based solar panels made of monocrystalline or polycrystalline silicon; these silicon-based panels present problems such as heavy weight, complex production processes, and relatively high energy consumption and costs during manufacturing.

[0003] To address the aforementioned problems, we propose solar cells that can be manufactured using a solution process. Among these are solar cells that utilize a perovskite-type crystal structure as a photoconversion layer, which are receiving significant attention as they approach the conversion efficiency of silicon-based solar cells.

[0004] However, because perovskite-type crystal structures are relatively brittle, it is difficult to maintain the constancy of the lattice shape for a long period in the operating environment, which becomes a factor that significantly affects the lifespan of perovskite solar cells.

[0005] In order to improve the stability of perovskite-type crystals, CN 106062983 A proposed that when manufacturing perovskite solar cells, a passivation layer containing a passivation agent such as thiophene or pyridine be further formed on the precipitated perovskite layer. However, the inventors have discovered that there is room for improvement in the selection of the passivation agent in the prior art.

[0006] In addition, in the prior art, a method for forming a passivation layer generally involves coating a layer supporting a perovskite layer with a solution containing a perovskite precursor, then coating with a reverse solvent to extract the perovskite solvent so that the perovskite structure precipitates, heating to remove excess solvent to transform the perovskite into an effective perovskite phase, coating a passivation agent on the surface of the perovskite, and finally annealing to remove the solvent, thereby forming a passivation layer on the perovskite layer. However, there is room for further simplification in this method for generating a passivation layer. The problem to be solved

[0007] Defects at deep and shallow energy levels exist in the manufacturing and operation processes of perovskite solar cells, and these defects have a serious impact on the efficiency and long-term stability of the cells. Through experiments, it was discovered that organic low-molecular-weight ammonium salts can passivate defects on the perovskite surface, thereby improving the efficiency and stability of the devices. However, most of the currently available passivation agents are monocyclic organic low-molecular-weight amines, and their effect on improving the efficiency and stability of the cell devices is not satisfactory.

[0008] The problem to be solved by the present invention is to provide a perovskite solar cell comprising a passivation layer having a superior effect of improving cell efficiency and stability, and a method for manufacturing a perovskite solar cell containing said passivation layer. means of solving the problem

[0009] One aspect of the present invention is a perovskite solar cell comprising at least an electrode, an electron transport layer, a hole transport layer, a perovskite layer, and a passivation layer, and

[0010] The above passivation layer contains a passivation agent, and the passivation agent comprises an aza-fused dicyclic compound and / or an organic salt composed of an aza-fused dicyclic compound and an acid, and each condensation ring of the aza-fused dicyclic compound is independently a saturated ring, an unsaturated ring, or an aromatic ring of 5 or 6, and the condensation ring of the aza-fused dicyclic compound contains 1 to 5 nitrogen atoms, and the condensation ring is a ring without substituents or a ring substituted by substituents having 1 to 3 carbon atoms.

[0011] In the above perovskite solar cell, preferably, the aza-fused dicyclic compound is selected from one of pteridine, 1,5,7-triazabicyclo(4.4.0)dek-5-ene, quinazolin, quinoline, 1,5-diazabicyclo[4.3.0]-5-nonene, imidazo[1,2-a]pyrimidine, 5,6,7,8-tetrahydroindolezine, 1-methyl-2,3-dihydro-1H-pyrrolizine and 2,4-dimethylquinoline.

[0012] In the above perovskite solar cell, preferably, the acid ion in the organic salt is selected from one of the acid ions containing O, S, P, N, F, I, Br, Cl, C, and H.

[0013] In the above perovskite solar cell, preferably, the acid ion is an acid ion selected from one of acetic acid, phosphoric acid, nitric acid, chloric acid, sulfonic acid, sulfuric acid, hydrofluoric acid, hydrochloric acid, hydrobromide, and hydroiodide.

[0014] In the above perovskite solar cell, preferably, the passivation layer is a layer formed by coating a reverse solvent in which a passivation agent is dissolved onto a perovskite layer. The reverse solvent is selected from at least one of toluene, chlorobenzene, dichlorobenzene, ethyl acetate, ether, benzene, anhydrous ethanol, isopropanol, butanol, chloroform, methylbutyrate, anisole, xylene, and trimethylbenzene.

[0015] In the above perovskite solar cell, preferably, the molar ratio of perovskite in the perovskite layer and passivation agent in the passivation layer is 100 to 800, and may be 200 to 600 or 250 to 400.

[0016] Thus, by using the above passivation agent, a perovskite solar cell with improved cell efficiency and stability can be obtained.

[0017] Another aspect of the present invention provides a power generation device using the perovskite solar cell. By doing so, a power generation device with improved efficiency and stability can be provided.

[0018] Another aspect of the present invention provides an electric device using the perovskite solar cell. By doing so, an electric device with improved efficiency and stability can be provided.

[0019] Another aspect of the present invention provides a method for forming a passivation layer of the perovskite solar cell, wherein the method comprises:

[0020] The method comprises the step of coating a perovskite precursor solution onto a layer supporting a perovskite layer, then directly coating a reverse solvent containing a passivation agent, and then annealing;

[0021] Here, the passivation agent comprises an aza-fused dicyclic compound and / or an organic salt composed of an aza-fused dicyclic compound and an acid, wherein each condensation ring of the aza-fused dicyclic compound is independently a saturated ring, an unsaturated ring, or an aromatic ring of 5 or 6 members, and the condensation ring of the aza-fused dicyclic compound contains 1 to 5 nitrogen atoms, and the condensation ring is a ring without substituents or a ring substituted by substituents having 1 to 3 carbon atoms.

[0022] In the above method, preferably, the aza-fused dicyclic compound is selected from one of pteridine, 1,5,7-triazabicyclo(4.4.0)dek-5-ene, quinazolin, quinoline, 1,5-diazabicyclo[4.3.0]-5-nonene, imidazo[1,2-a]pyrimidine, 5,6,7,8-tetrahydroindolezine, 1-methyl-2,3-dihydro-1H-pyrrolizine, and 2,4-dimethylquinoline.

[0023] In the above method, preferably, the acid ion in the organic salt is selected from one of the acid ions containing O, S, P, N, F, I, Br, Cl, C, and H.

[0024] In the above method, preferably, the acid ion is an acid ion selected from one of acetic acid, phosphoric acid, nitric acid, chloric acid, sulfonic acid, sulfuric acid, hydrofluoric acid, hydrochloric acid, hydrobromide, and hydroiodide.

[0025] In the above method, preferably, the reverse solvent is selected from at least one of toluene, chlorobenzene, dichlorobenzene, ethyl acetate, ether, benzene, anhydrous ethanol, isopropanol, butanol, chloroform, methylbutyrate, anisole, xylene, and trimethylbenzene.

[0026] In the above method, preferably, the concentration of the passivation agent in the reverse solvent is 0.1 to 10 mmol / mL.

[0027] In the above method, preferably, the molar ratio of the perovskite precursor in the perovskite precursor solution to the passivation agent in the reverse solvent is 200 to 8000, and may be 800 to 1600 or 1000 to 1200.

[0028] Thus, a passivation layer can be formed in a simpler manner, and by passivating the surface and grain boundaries of the perovskite structure in all directions, a perovskite solar cell with superior cell efficiency and stability can be provided. Effects of the invention

[0029] The perovskite solar cell according to the present invention can improve cell efficiency and stability, and the manufacturing method according to the present invention can provide a perovskite solar cell having the above advantages in a simpler way. Brief explanation of the drawing

[0030] Figure 1 is a schematic diagram of the structure of a perovskite solar cell. Figure 2 is a schematic diagram of the structure of perovskite. (Explanation of symbols) 1: Substrate; 2: First electrode; 3: Electron / hole transport layer; 4: Perovskite layer; 5: Passivation layer; 6: Hole / electron transport layer; 7: Second electrode Specific details for implementing the invention

[0031] To clarify the technical problem to be solved by the present invention, the technical means of solution, and the beneficial effects, the present invention is described in more detail by combining the drawings and embodiments. It should be understood that the specific embodiments described herein are used solely to explain the present invention and are not intended to limit the invention.

[0032] 1 Perovskite solar cells

[0033] First, a perovskite solar cell according to the present invention will be briefly described. As shown in FIG. 1, the perovskite solar cell according to the present invention sequentially comprises a first electrode layer (2), an electron transport layer (3), a perovskite layer (4), a passivation layer (5), a hole transport layer (6), and a second electrode layer (7). When light is irradiated onto the perovskite layer, the perovskite structure absorbs the energy of the photons to generate free electrons and holes (hereinafter, electrons and holes are collectively referred to as “carriers”), and the generated free electrons and holes are conducted to the first electrode and the second electrode through the electron transport layer and the hole transport layer, respectively, and a voltage is generated between the first electrode and the second electrode, thereby realizing energy conversion between photovoltaics. Figure 1 is merely an exemplary embodiment in which a passivation layer (5) is formed on one side of a perovskite layer (4), and the present invention is not limited to this structure, and for example, a passivation layer (5) may be formed on either one side or both sides of the perovskite layer (4).

[0034] 1.1 Perovskite layer (4)

[0035] The perovskite layer contains crystals of a perovskite structure having the crystal structure shown in Fig. 2. The structure of perovskite commonly used in solar cells can be represented as an ABX3 structure, where A is a positively charged ion with a constant size, such as an ion of an alkali metal such as cesium, or an ion of a low-molecular-weight nitrogen-containing organic substance such as methylamine (CH3NH2) or formamidine (HNCHNH2); the B position is an ion of a transition metal element such as a Pb or Sn ion; and the X position is a halogen ion such as a Br or I ion.

[0036] It needs to be explained that in a typical ABX3 structure, A is filled into a BX octahedron composed of B and X to form a lattice structure, so there are specific size requirements for the cation at the A position, and generally, these size requirements are referred to as the “tolerance factor,” and the tolerance factor must be between 0.8 and 1.2. If the tolerance factor is too large or too small, it significantly affects the stability of the lattice structure or prevents the formation of the desired structure.

[0037] The instability of the perovskite structure is, specifically, related to defects in deep and shallow energy levels present during the manufacturing process and operation of perovskite solar cells, and these defects have a serious impact on cell efficiency and long-term stability. In addition, the instability of the calcium structure is also due to its tendency to hydrolyze when it comes into contact with water.

[0038] 1.2 Passivation layer (5)

[0039] A passivation layer is a layer installed between a perovskite layer and an electron transport layer and / or a hole transport layer to improve the stability of the perovskite structure and the lifespan of the solar cell equipment, and contains a passivation agent.

[0040] The inventors have discovered that, compared to conventional passivation agents, using the following passivation agent results in a superior effect of improving battery efficiency and extending battery life. The passivation agent according to the present invention comprises an aza-fused dicyclic compound and / or an organic salt composed of an aza-fused dicyclic compound and an acid, wherein each condensation ring of the aza-fused dicyclic compound is independently a saturated ring, an unsaturated ring, or an aromatic ring composed of five or six members, and the condensation ring of the aza-fused dicyclic compound comprises one to five nitrogen atoms, and said condensation ring is a ring without substituents or a ring substituted by substituents having one or two carbon atoms with a number of one to three.

[0041] The substituents on the above condensed ring may be hydrocarbon groups, alcohol groups, ether groups, ester groups, aldehyde groups, ketone groups, carboxyl groups, carbonyl groups, amide groups, imide groups, or combinations thereof, specifically, methyl groups, ethyl groups, n-propyl groups, isopropyl groups; methanol groups, ethanol groups, n-propanol groups, isopropanol groups; methyl ether groups, ethyl ether groups, propyl ether groups; methyl ester groups, ethyl ester groups, propyl ester groups; formaldehyde groups, acetaldehyde groups, propionaldehyde groups; methyl ketone groups, ethyl ketone groups, acetone groups; formic acid groups, acetic acid groups, propionic acid groups; formamide groups, acetamide groups, propionamide groups.

[0042] For example, if formamidine is used at position A, it acts as an organic component; since high temperatures from direct sunlight and non-radiative recombination caused by defects both raise the device temperature, the formamidine volatilizes, which can induce defects at position A. Conventional interfacial passivation agents mostly form two-dimensional structures to prevent the volatilization of cations at position A, but the A position may shift, forming defects in multiple locations. An increase in defects traps carriers such as free electrons or holes, increasing the internal resistance of the device; consequently, the difficulty of carrier extraction increases, and the short-circuit current decreases. The decomposition of perovskite reduces device stability. Therefore, passivation using conventional passivation agents does not provide good improvement in the long-term stability of the device.

[0043] In the present invention, defects at the perovskite grain boundaries and on the surface are passivated using a passivation agent containing the aza-fusion dicyclic compound and / or an organic salt composed of the aza-fusion dicyclic compound and / or an acid.

[0044] The cyclic nitrogen atom in the organic salt composed of the aza-fused dicyclic compound and / or the acid thereof in the passivation agent according to the present invention has a relatively strong proton bonding ability and forms a strong chemical bond with the A position, thereby preventing the decomposition or volatilization of the A position cation due to various causes, and harmful hydrogen vacancies are not easily generated during use, thus improving the stability of the passivation and the efficiency of the device.

[0045] Specific examples of the above-mentioned aza-fused cyclic compounds include the materials used in the examples, but the present invention is not limited to such compounds.

[0046] Although the principle is not entirely clear, it can be inferred that compared to the prior art, the number of rings in the compound used in the present invention is increased, thereby improving the hydrophobicity of the material and allowing hydrophobic functional groups to be introduced, which can significantly enhance the water stability of the perovskite. Furthermore, since the nitrogen on the nitrogen heteroring and the A position of the perovskite possess a relatively strong proton bonding ability, the loss of A position ions can be suppressed, thereby enhancing the passivation effect.

[0047] The acid ion in the organic salt formed with the above compound is selected from one of the acid ions containing O, S, P, N, F, I, Br, Cl, C, and H.

[0048] Specifically, examples include acid ions selected from one of acetic acid, phosphoric acid, nitric acid, chloric acid, sulfonic acid, sulfuric acid, hydrofluoric acid, hydrochloric acid, hydrobromide, and hydroiodide.

[0049] Preferably, the acid ion is selected from one of hydrofluoric acid, hydrochloric acid, hydrobromide, and hydroiodic acid, because when a halogen is used as the acid ion, it can fill halogen vacancies on the perovskite surface. It is more preferable for the acid ion to be selected from hydrofluoric acid, as it can fill defects at the X-position and stabilize the A-position cation by forming hydrogen bonds with it.

[0050] Additionally, preferably, the acid ion is selected from one of acids containing oxygen, sulfur, phosphorus, etc., such as carboxylic acids, sulfonic acids, sulfuric acids, and phosphoric acids. This is because the acid ion selected from these acids can form a hydrogen bond with the ion at the A position while simultaneously anchoring the ion at the B position, thereby stabilizing the ions at the A and B positions and stabilizing the perovskite structure, which further enhances the long-term stability of the battery device.

[0051] In the above perovskite solar cell, preferably, the molar ratio of perovskite in the perovskite layer to the passivation agent in the passivation layer (molar amount of perovskite / molar amount of passivation agent) is 100 to 800, and may be 200 to 600 or 300 to 400. If the amount of passivation agent is too small compared to the perovskite, defects in the perovskite structure cannot be sufficiently passivated, and ideal hydrophobicity cannot be imparted. If the amount of passivation agent is too large, the passivation effect reaches a saturation state, which reduces cost efficiency and may cause adverse effects such as carrier transport interference, increased internal resistance, and even cell failure.

[0052] 1.3 Electron transport layer (3) and hole transport layer (6)

[0053] The electron transport layer and the hole transport layer are layers formed on both sides of the perovskite layer and the passivation layer, and are used to transport free electrons and holes generated by the perovskite layer, respectively. By separating electrons and holes and further transporting them to the first electrode and the second electrode, the conversion efficiency is prevented from decreasing due to the recombination of holes and electrons. It should be noted that FIG. 1 illustrates only one case that can be used in the present invention, and the positions of the electron transport layer and the hole transport layer of the present invention are also interchangeable.

[0054] In the visible light band, the light transmittance of at least one of the electron transport layer and the hole transport layer is 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, and 95% or more.

[0055] The electron transport layer is composed of conventional electron transport materials, and those skilled in the art may appropriately select them within a range favorable to conversion efficiency. For example, tin oxide, titanium oxide, PCBM, and C60 may be used, preferably tin oxide. In addition, the layer may be manufactured by appropriately combining conventional methods such as coating, deposition, and annealing.

[0056] The hole transport layer is composed of conventional hole transport materials, and those skilled in the art may appropriately select them within a range favorable to conversion efficiency. For example, PTAA, spiro, and PEDOT:PSS may be used, preferably spiro. In addition, the layer may be manufactured by appropriately combining conventional methods such as coating, deposition, and annealing.

[0057] 1.4 First electrode (2) and second electrode (7)

[0058] The first electrode is stacked in the direction of the electron transport layer opposite to the direction of the perovskite layer, and is an electrode that guides electrons conducted from the electron transport layer to the outside for use. The second electrode is stacked in the direction of the hole transport layer opposite to the direction of the perovskite layer, and is an electrode that guides holes conducted from the hole transport layer to the outside for use. It should be noted that FIG. 1 illustrates only one case that can be used in the present invention, and the positions of the first electrode and the second electrode of the present invention are interchangeable.

[0059] When the first electrode and the second electrode are opaque electrodes, they may be composed of conventional materials used for electrodes, and a person skilled in the art may appropriately select them within a range advantageous to conversion efficiency. For example, gold, silver, copper, aluminum, etc. may be used, and preferably gold. In addition, the method of manufacturing the above layer may be to appropriately combine conventional methods such as coating, deposition, and annealing.

[0060] At least one of the first electrode and the second electrode is a transparent electrode, and the light transmittance of the transparent electrode in the visible light band is 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more. In the case of a transparent electrode, it may be composed of conventional materials used for transparent electrodes, and a person skilled in the art may appropriately select within a range advantageous to conversion efficiency. For example, conductive oxides, metal lattices, ultrathin metal layers, nano metal wires, carbon-based transparent materials, polymers, etc. may be used. Conductive oxides are preferred in that they have high light transmittance. In addition, the electrode may be manufactured by appropriately combining conventional methods such as coating, deposition, and annealing.

[0061] 1.5 substrate (1)

[0062] If necessary, a substrate may be additionally provided on the outer side of the first electrode and / or the second electrode. The substrate is used to support the entire perovskite solar cell and facilitates handling and assembly.

[0063] The above substrate may be an organic or inorganic flexible material such as polyimide (PI), polybutylene terephthalate (PET), polyamide (PA), polycarbonate (PC), or ultra-thin glass, or a rigid material such as a glass plate or a metal plate.

[0064] In the case where a substrate is present on both the outer sides of the first electrode and the second electrode, the light transmittance of at least one substrate in the visible light band is 50% or more, 60% or more, 70% or more, 80% or more, 90% or more, or 95% or more. Additionally, the light-transmitting substrate is configured on one side of the transparent electrode.

[0065] Additionally, if the first electrode and / or the second electrode have sufficient capability to support the perovskite solar cell, the substrate may be omitted.

[0066] 2 Method for manufacturing perovskite solar cells

[0067] A method for manufacturing a perovskite solar cell according to the present invention is,

[0068] The method comprises the steps of coating a perovskite precursor solution onto a layer supporting a perovskite layer (Step 1), directly coating a reverse solvent containing the passivation agent onto the perovskite precursor solution layer (Step 2), and annealing (Step 3). Among these, the coating in Steps 1 and 2 may use conventional methods such as spin coating, scratch coating, roll coating, or spray coating, but spin coating is preferred in that the thickness can be controlled relatively well.

[0069] This manufacturing method simplifies the passivation layer manufacturing step and can prevent the effects of multiple annealing on the perovskite structure. In addition, passivation can be realized during the process of forming the perovskite structure.

[0070] Specifically, compared to the prior art, the method according to the present invention can reduce the number of annealing treatments and prevent multiple annealing of perovskite, thereby reducing time costs and improving manufacturing efficiency.

[0071] In addition, in the method according to the present invention, when the perovskite phase is unstable, a passivation agent is added so that the passivation agent binds better with the perovskite at the grain boundaries and surfaces, thereby making the perovskite phase more stable.

[0072] Since the passivation agent can not only exist on the surface of the perovskite layer but also penetrate deep into the grain boundaries, it is possible to passivate both the grain boundaries and the surface simultaneously, thereby realizing omnidirectional passivation. This allows for more effective prevention of electron-hole recombination at the grain boundaries and the surface. Furthermore, even when the grain boundaries are relatively small, using the method according to the present invention enables a passivation agent with a relatively large molecular volume to penetrate deep into the grain boundaries. At the same time, since the passivation agent exists only in the inverse solvent, it does not affect the formation of the perovskite structure. This is difficult to realize with prior art.

[0073] 2.1 Perovskite precursor solution

[0074] The perovskite precursor solution contains a perovskite precursor and a solvent. Specifically, the perovskite precursor is a substance containing A ions, B ions, and X ions. An example of a perovskite precursor solution is a mixture of BX2 and AX in the solvent. As previously mentioned, A can be selected from alkali metals such as cesium or low molecular weight nitrogen-containing organic compounds such as methylamine or formamidine, B is Sn or Pb, and X is a halogen.

[0075] The solvent in the perovskite precursor solution can be appropriately selected from currently commonly used solvents as long as it dissolves BX2 and AX, is mutually soluble with the inverse solvent, and can be removed by heating. A person skilled in the art can prepare a perovskite precursor solution by selecting any appropriate combination from the prior art.

[0076] The molar ratio of BX2 to AX (BX2 / AX) is 1 or more, 1.01 or more, 1.02 or more, 1.03 or more, 1.04 or more, and 1.05 or more in terms of sufficiently forming a perovskite layer structure, and is 1.5 or less, 1.4 or less, 1.3 or less, 1.2 or less, and 1.1 or less in terms of cost reduction.

[0077] In a perovskite precursor solution, the concentration of the perovskite precursor is used to control the thickness of the formed perovskite layer, and the ideal concentrations, calculated in terms of BX2 concentration, are 0.2–5 mmol / mL, 0.3–4 mmol / mL, 0.4–3 mmol / mL, and 0.5–2 mmol / mL. At these concentrations, it is advantageous to form a satisfactory perovskite structure.

[0078] It needs to be explained that the tolerance factor of the A ion must be 0.8 to 1.2. If the tolerance factor exceeds 1.2 because the volume of the ion is too large, there is a concern that lattice deformation may occur or it may be difficult to fill up to the BX octahedral structure, making it impossible to form a perovskite structure. Even if this structure can be formed, the perovskite may be blocked during the crystallization process, degrading the crystal quality of the perovskite. Furthermore, too many grain boundaries may be formed, resulting in deep energy level defects and carrier capture, which may lead to a decrease in photoelectric conversion efficiency and stability.

[0079] When containing two or more A ions, the tolerance factor is preferably 0.8 to 1.2 for all. This is because, as described above, if a relatively large molecule is present, the crystal structure is destroyed, and even when used as an additive, the crystal quality is poor and it is difficult to achieve good stability due to the relatively large structure.

[0080] 2.2 Solution containing a passivation agent

[0081] In this method, the solution containing the passivation agent comprises a reverse solvent and a passivation agent.

[0082] The reverse solvent is a solvent used to convert a perovskite precursor into a perovskite structure. In the present invention, the reverse solvent is a solvent with low solubility of the perovskite precursor and is selected from at least one of toluene, chlorobenzene, dichlorobenzene, ethyl acetate, ether, benzene, anhydrous ethanol, isopropanol, butanol, chloroform, methylbutyrate, anisole, xylene, and trimethylbenzene. Preferably, the reverse solvent is a mixed solvent formed by adding at least one second reverse solvent selected from ether, benzene, anhydrous ethanol, isopropanol, butanol, chloroform, methylbutyrate, anisole, xylene, and trimethylbenzene to at least one first reverse solvent selected from toluene, chlorobenzene, dichlorobenzene, and ethyl acetate.

[0083] By adjusting the ratio of the first reverse solvent to the second reverse solvent in the reverse solvent, the solubility of the precursor in the reverse solvent can be controlled, and thus the precipitation rate and crystal size of the perovskite structure can be controlled when the reverse solvent comes into contact with the precursor in the precursor solution.

[0084] In the reverse solvent, the ratio (volume) of the first reverse solvent to the second reverse solvent is 100:0 to 100:50, and preferably 100:0 to 100:10. By preparing the reverse solvent by mixing in this ratio, the precipitation rate and crystal size of the perovskite structure can be advantageously controlled.

[0085] The reverse solvent of the present invention contains a passivation agent according to the present invention, which is not described redundantly herein. It should be noted that a passivation agent according to the prior art can also be used in the method for forming a passivation layer according to the present invention. It is used as a passivation agent according to the prior art.

[0086] In the reverse solvent, the concentration of the passivation agent is 0.1 to 10 mmol / mL, and may be 0.5 to 8 mmol / mL, 1 to 5 mmol / mL, or 2 to 3 mmol / mL. Within the above range, the content of the passivation agent in the passivation layer can be easily controlled without affecting the precipitation of the perovskite structure.

[0087] The molar ratio (R) of the perovskite precursor in the perovskite precursor solution and the passivation agent in the reverse solvent is 200 to 8000, and can be 800 to 1600 or 1000 to 1200. If the amount of passivation agent is too small compared to the perovskite precursor, defects in the perovskite structure cannot be sufficiently passivated, nor can ideal hydrophobicity be imparted. If the amount of passivation agent is too large, the passivation effect reaches a saturation state, which reduces cost efficiency and can cause adverse effects such as carrier transport interference, increased internal resistance, and even battery failure.

[0088] 2.3 annealing

[0089] In the present invention, a perovskite precursor solution and a reverse solvent are coated, and then an annealing treatment is performed. During the annealing process, the solvent and reverse solvent in the precursor solution volatilize, and the precursor precipitates to form a perovskite structure, thereby forming a perovskite layer and a passivation layer, while the passivation agent passivates the grain boundaries and surfaces of the perovskite structure.

[0090] The annealing treatment conditions can be appropriately set according to the type of solvent used and the annealing equipment parameters, and are not specifically limited. However, in order to obtain a perovskite structure with good order, annealing can be performed at 80°C to 200°C for 10 minutes to 2 hours. For example, the annealing conditions in the examples described below can be used.

[0091] 3 Power generation device

[0092] The power generation device according to the present invention is a power generation device comprising the perovskite solar cell, wherein the perovskite solar cell may be one or more. The power generation device further comprises a control system and a transmission system. Through the control system and the transmission system, the power generation device according to the present invention can adjust the electrical energy generated from the solar cell into electrical energy suitable for electrical equipment. It should be explained that, here, “comprising” means a case where an electrical connection exists between the power generation device and the solar cell.

[0093] 4 electrical device

[0094] The electric device according to the present invention is an electric device comprising the perovskite solar cell, wherein the perovskite solar cell may be one or more. The electric device further comprises a system for utilizing electrical energy generated from the perovskite solar cell. Examples of the system utilizing electrical energy include a system for converting electrical energy into kinetic energy, internal energy, light energy, or chemical energy. It should be explained that, here, "includes" means a case where an electrical connection exists between the electric device and the solar cell.

[0095] Examples

[0096] Hereinafter, embodiments according to the technical solution of the present application will be described in detail. The following embodiments are intended only to more clearly explain the technical solution of the present application and shall not limit the scope of protection of the present application.

[0097] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by a person skilled in the art of the technical field of this application; terms used herein are for the purpose of describing specific embodiments only and are not intended to limit this application; and terms “include,” “having,” and any variations thereof in the specification, claims, and description of the drawings of this application are intended to encompass non-exclusive inclusion.

[0098] In the description of the embodiments of this application, technical terms such as “first,” “second,” etc. are intended merely to distinguish different objects and should not be understood as indicating or implying relative importance, or implicitly indicating the quantity, specific order, or master-slave relationship of the indicated technical features. In the description of the embodiments of this application, unless otherwise explicitly and specifically limited, the meaning of “plural” is two or more.

[0099] The term “Examples” as used in this specification means that specific features, structures, or characteristics described in connection with an Example may be included in at least one Example of this Application. Where the word appears in each place in the specification, it does not necessarily mean the same Example, nor does it mean an independent or alternative Example excluded from other Examples. Those skilled in the art will understand, both explicitly and implicitly, that the Examples described in this specification may be combined with other Examples.

[0100] In the description of the embodiments of the present application, the term “and / or” is used merely to describe the relationship between related objects and indicates that three relationships may exist; for example, A and / or B may represent three cases: A existing alone, B existing alone, and A and B coexisting. Additionally, in this specification, the letter “ / ” generally indicates that the objects related before and after are in an “or” relationship.

[0101] In the description of the embodiments of the present application, orientations or positional relationships indicated by technical terms such as “inside”, “outside,” etc., are based on orientations or positional relationships illustrated in the drawings and are intended only to facilitate the description and brief explanation of the embodiments of the present application; they do not indicate or imply that the indicated device or element must be configured and operated in a specific orientation or specific orientation, and therefore should not be understood as a limitation on the embodiments of the present application.

[0102] Although the embodiments of this application illustrate only perovskite solar cells of a general structure, the present invention can also be applied to perovskite solar cells of an inverted structure.

[0103] Manufacturing of perovskite solar cells

[0104] Example 1

[0105] [Manufacturing of Electron Transport Layer]

[0106] A 15% tin oxide solution and deionized water were mixed in a 1:3 ratio and stirred at room temperature for 1 hour. Then, 70 μL was taken and spin-coated onto a conductive glass surface, and heated at 150°C for 15 minutes.

[0107] [Preparation of Perovskite Layer and Passivation Layer]

[0108] A perovskite solution was prepared by adding AX (iodoformamidine and chloromethylamine) and BX2 (lead iodide) to a mixed solution of DMF and DMSO (DMF:DMSO=4:1) in a ratio of BX2 / AX=1.05. The solution was then magnetically stirred at room temperature for 1 hour, filtered, and used. The final concentration of the perovskite precursor in the solution was 1.5 mmol / mL based on lead iodide. The passivation materials described in Tables 1 and 2 below were dissolved in the reverse solvent. A conductive glass spin-coated with an electron transport layer was irradiated with UV light for 15 minutes, then 60 μL of perovskite solution was added dropwise onto the glass, followed by the addition of 600 μL of reverse solvent containing dissolved passivation material, and then annealed at 150°C for 1 hour to simultaneously form a perovskite layer and a passivation layer, and finally, a 500 nm thick perovskite layer and a 2 nm thick passivation layer were formed. The ratio of the amount of perovskite to the passivation agent (molar ratio) is 300.

[0109] [Manufacturing of Hole Transport Layer]

[0110] Li-TFSI, tBP, and FK209 were added to spiro, stirred for 1 hour, and then filtered for use. 60 μL of spiro was dropped onto conductive glass having a perovskite layer and a passivation layer formed thereon, and then spin-coated to form a hole transport layer.

[0111] [Manufacturing of Back Electrode]

[0112] A complete perovskite solar cell was obtained by forming a silver layer with a thickness of 80 nm on the hole transport layer formed by the spin coating above using a vacuum deposition system with a conventional method.

[0113] Examples 2–16

[0114] Perovskite solar cells were manufactured using the same method as in Example 1, except that the formation conditions of the perovskite layer and the passivation layer were replaced as shown in Tables 1 and 2.

[0115] Comparative Examples 1-3

[0116] Perovskite solar cells were prepared in the same manner as in Example 1, except that the passivation agent shown in Tables 1 and 2 was added to the perovskite precursor solution and the passivation agent was not added to the reverse solvent.

[0117] Comparative Example 4

[0118] Perovskite solar cells were prepared using the same method as in Example 1, except that no passivation agent was added.

[0119] [Table 1]

[0120]

[0121] [Table 2]

[0122]

[0123] Battery Characteristics Test (IV Test)

[0124] For each of the 20 solar cells according to each example and comparative example obtained by the above method, an IV test was performed at one solar intensity of 25°C using a solar simulator from Enlitech, and the average value of the test results of the solar cells according to each example and comparative example is shown in Table 3 below.

[0125] [Table 3]

[0126]

[0127] Stability test

[0128] Twenty solar cells each according to each example and comparative example obtained by the above method were stored in a humidity-controlled glove box and aged for 30 days under conditions of constant temperature 25°C and constant humidity 60%RH to perform a stability test. The average value of the I-V test results of the undamaged cells, the efficiency retention rate, the number of damaged cells, and the damage rate after the stability test according to each example, comparative example, and reference example are shown in Table 4 below.

[0129] [Table 4]

[0130]

[0131] From the results of Tables 3 and 4 above, it can be seen that compared to a cell without the passivation agent according to the present invention, a perovskite solar cell using the passivation agent according to the present invention has a more significant effect on improving device efficiency and stability, and that the cell efficiency of a cell without passivation significantly decays after being left for a certain period of time; and when the cation is the same, if an organic acid containing elements such as O, S, P, and N is used as the acid ion, the passivation effect is better. In addition, the cell damage rate of a perovskite solar cell using the passivation agent according to the present invention was significantly suppressed after being left for a certain period of time.

[0132] In addition, compared to a method not using the method according to the present invention, a perovskite solar cell obtained using the method for manufacturing a passivation layer and a perovskite layer according to the present invention has superior device stability by preventing secondary heating annealing of the perovskite; furthermore, in the case of a wet film, it was discovered that by adding a passivation material and controlling the crystal structure, the passivation material is better filled into the grain boundaries and surfaces, thereby better protecting the perovskite and improving the stability of the perovskite.

[0133] [Industrial Applicability]

[0134] The present invention can provide a perovskite solar cell with high energy conversion efficiency and excellent stability, as well as a method for manufacturing the perovskite solar cell. This has significant implications for addressing climate change and building an ecological civilization.

Claims

Claim 1 In a perovskite solar cell, the perovskite solar cell comprises at least an electrode, an electron transport layer, a hole transport layer, a perovskite layer, a passivation layer, and an optional substrate layer, wherein the passivation layer contains a passivation agent, and the passivation agent comprises an aza-fused dicyclic compound and / or an organic salt composed of the aza-fused dicyclic compound and an acid, wherein each condensation ring of the aza-fused dicyclic compound is independently a saturated ring, an unsaturated ring, or an aromatic ring of a pentagon or a hexagonal group, and the condensation ring of the aza-fused dicyclic compound comprises 1 to 5 nitrogen atoms, and the condensation ring is a ring without substituents or a ring substituted by substituents having 1 to 3 carbon atoms, and the acid ion in the organic salt is selected from one of acid ions containing O, S, P, N, F, I, Br, and C, and in the perovskite layer A perovskite solar cell characterized in that the molar ratio of the passivation agent in the perovskite and the passivation layer is 100 to 800, and the aza-fused dicyclic compound is selected from one of pteridine, 1,5,7-triazabicyclo(4.4.0)dek-5-ene, quinazolin, 1,5-diazabicyclo[4.3.0]-5-nonene and imidazo[1,2-a]pyrimidine. Claim 2 A perovskite solar cell according to claim 1, characterized in that the acid ion is an acid ion selected from any one of acetic acid, phosphoric acid, nitric acid, sulfonic acid, sulfuric acid, hydrofluoric acid, hydrobromide, and hydroiodide. Claim 3 A perovskite solar cell according to claim 1, wherein the passivation layer is a layer formed by coating a reverse solvent in which the passivation agent is dissolved onto the perovskite layer, and the reverse solvent is selected from at least one of toluene, chlorobenzene, dichlorobenzene, ethyl acetate, ether, benzene, anhydrous ethanol, isopropanol, butanol, chloroform, methylbutyrate, anisole, xylene, and trimethylbenzene. Claim 4 A perovskite solar cell according to claim 1, characterized in that the molar ratio of the perovskite in the perovskite layer to the passivation agent in the passivation layer may be 200 to 600 or 250 to 400. Claim 5 A power generation device characterized by including a perovskite solar cell according to any one of claims 1 to 4. Claim 6 An electric device characterized by comprising a perovskite solar cell according to any one of claims 1 to 4. Claim 7 A method for manufacturing a perovskite solar cell comprises the steps of: coating a perovskite precursor solution onto a layer supporting a perovskite layer; directly coating a reverse solvent containing a passivation agent; and then annealing. The passivation agent comprises an aza-fused cyclic compound or an organic salt composed of the aza-fused cyclic compound and an acid, wherein each condensation ring of the aza-fused cyclic compound is independently a saturated ring, an unsaturated ring, or an aromatic ring consisting of five or six members, and the condensation ring of the aza-fused cyclic compound comprises 1 to 5 nitrogen atoms, and the condensation ring is a ring without substituents or a ring substituted by substituents having 1 to 3 carbon atoms, and the acid ion in the organic salt is selected from one of acid ions containing O, S, P, N, F, I, Br, and C, and the molar ratio of the perovskite precursor in the perovskite precursor solution to the passivation agent in the inverse solvent is 200 to 8000, and the aza-fused cyclic compound is pteridine, A method for manufacturing a perovskite solar cell characterized by being selected from one of 1,5,7-triazabicyclo(4.4.0)dek-5-ene, quinazolin, 1,5-diazabicyclo[4.3.0]-5-nonene and imidazo[1,2-a]pyrimidine. Claim 8 A method of manufacturing according to claim 7, characterized in that the acid ion is an acid ion selected from any one of acetic acid, phosphoric acid, nitric acid, sulfonic acid, sulfuric acid, hydrofluoric acid, hydrobromide, and hydroiodide. Claim 9 A method of manufacturing according to claim 7 or 8, wherein the reverse solvent is selected from at least one of toluene, chlorobenzene, dichlorobenzene, ethyl acetate, ether, benzene, anhydrous ethanol, isopropanol, butanol, chloroform, methylbutyrate, anisole, xylene, and trimethylbenzene. Claim 10 A manufacturing method according to claim 7 or 8, characterized in that, in the reverse solvent, the concentration of the passivation agent is 0.1 to 10 mmol / mL. Claim 11 A manufacturing method according to claim 7 or 8, characterized in that the molar ratio of the perovskite precursor in the perovskite precursor solution to the passivation agent in the reverse solvent may be 800 to 1600 or 1000 to 1200. Claim 12 delete Claim 13 delete Claim 14 delete Claim 15 delete

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