Composite hole transport layer, preparation method and application thereof, and perovskite battery and preparation method thereof

Abstract

The application provides a composite hole transport layer and a preparation method and application thereof, and a perovskite battery and a preparation method thereof, and belongs to the technical field of perovskite batteries. The composite hole transport layer comprises a first hole transport layer and a second hole transport layer; the first hole transport layer comprises nickel oxide; and the second hole transport layer comprises thiazole blue and a carbazole self-assembled monomer. By adopting nickel oxide, thiazole blue and a carbazole self-assembled monomer, the application can improve the uniformity of SAM molecular arrangement and induce the formation of a more compact and flat interface monolayer through the pi-pi interaction between thiazole blue molecules and the carbazole self-assembled monomer. Meanwhile, the N atoms in the thiazole blue molecules are combined with nickel oxide to reduce high-valence nickel, thereby passivating the interface traps between the nickel oxide and the perovskite, forming a bifunctional passivation molecular bridge facing both the nickel oxide end and the perovskite end, significantly adjusting the bottom interface of the perovskite battery and improving the device performance.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of perovskite battery, in particular to a composite hole transport layer and a preparation method and application thereof, and a perovskite battery and a preparation method thereof. BACKGROUND

[0002] Perovskite battery has become one of the most potential new generation photovoltaic technologies in recent years due to its high photoelectric conversion efficiency, low processing cost and good material flexibility.

[0003] Nickel oxide (NiO x ) has excellent stability and high work function, and is widely used in the hole transport layer (HTL) of perovskite battery. However, there are serious interface problems between the nickel oxide layer and the perovskite layer at present, including band mismatch, high interface defect state density and non-radiative recombination, which seriously limit the fill factor and open circuit voltage of the device. Modifying the nickel oxide layer with self-assembled monolayers (SAM) is one of the effective means to optimize the interface energy level structure and improve the performance of the device. The SAM molecules are combined with the surface of the nickel oxide layer through the anchor head with phosphoric acid group, and the organic end has excellent hole transport capacity and is beneficial to the band alignment with perovskite. However, in the current SAM modified nickel oxide layer system, the SAM molecules are not arranged densely and uniformly on the surface of the nickel oxide, and island or aggregation structure is easily formed, resulting in discontinuous interface, significant interface recombination between nickel oxide and perovskite, and further film defect, unpassivated surface of nickel oxide and perovskite, which significantly affects the performance of the perovskite battery device. SUMMARY

[0004] Therefore, the main purpose of the present application is to provide a composite hole transport layer and a preparation method and application thereof, and a perovskite battery and a preparation method thereof. By introducing thiazole blue molecules into the carbazole self-assembled monolayer, a blended precursor with the function of interface bridging agent is formed. The thiazole blue molecules have an extended π-conjugated structure, which can produce π-π interaction with the carbazole self-assembled monolayer, promote the uniform arrangement of the SAM molecules, and induce the formation of a more dense and flat hole transport layer. At the same time, the thiazole blue molecules have reversible redox behavior, and the amine group in the thiazole blue and the N atom in the thiazole ring preferentially combine with nickel oxide and selectively reduce high-valence nickel, thereby passivating the interface traps between nickel oxide and perovskite and improving the performance of the device.

[0005] In a first aspect, the present application provides a composite hole transport layer, comprising a first hole transport layer and a second hole transport layer.

[0006] The first hole transport layer comprises nickel oxide.

[0007] The second hole transport layer comprises thiazole blue and carbazole self-assembled monolayer.

[0008] In some embodiments, the mass ratio of the thiazole blue and the carbazole self-assembled monomer is 1:10-1:4.

[0009] In some embodiments, the carbazole self-assembled monomer comprises one or more of [2-(9H-carbazol-9-yl)ethyl]phosphonic acid, [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid, [2-(3,6-dimethyl-9H-carbazol-9-yl)ethyl]phosphonic acid, [4-(9H-carbazol-9-yl)ethyl]phosphonic acid, [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid, [4-(3,6-dimethoxy-9H-carbazol-9-yl)butyl]phosphonic acid, [4-(7H-dibenzo[c,e][1,2]oxazin-7-yl)butyl]phosphonic acid, [2-(9-bromocarbazol-9-yl)ethyl]phosphonic acid, [2-(9-chlorocarbazol-9-yl)ethyl]phosphonic acid, [4-(9-bromocarbazol-9-yl)butyl]phosphonic acid, and [4-(9-fluorocarbazol-9-yl)butyl]phosphonic acid.

[0010] In some embodiments, the first hole transport layer has a thickness of 5-40 nm, and the second hole transport layer has a thickness of 1-3 nm.

[0011] In a second aspect, the application provides a method for preparing the composite hole transport layer of the first aspect, comprising the following steps:

[0012] mixing the thiazole blue, the carbazole self-assembled monomer, and a solvent to prepare a mixed solution;

[0013] coating the mixed solution on the first hole transport layer to prepare a second hole transport layer.

[0014] In some embodiments, the solvent comprises one or more of methanol, ethanol, isopropanol, and N,N-dimethylformamide.

[0015] In a third aspect, the application provides use of the composite hole transport layer of the first aspect or the composite hole transport layer prepared by the method of the second aspect in a perovskite battery.

[0016] In a fourth aspect, the application provides a perovskite battery, comprising, in sequence, a conductive substrate, a composite hole transport layer, a perovskite layer, an electron transport layer, a barrier layer, and an electrode layer.

[0017] The composite hole transport layer is the composite hole transport layer of the first aspect or the composite hole transport layer prepared by the method of the second aspect.

[0018] The second hole transport layer is located between the first hole transport layer and the perovskite layer.

[0019] In some embodiments, the perovskite layer comprises a compound shown in Formula 1:

[0020] ABX3 Formula 1;

[0021] Wherein, A is one or more of formamidinium cation, methylamine cation and cesium ion; B is lead; X is one or more of fluoride ion, chloride ion, bromide ion and iodide ion.

[0022] In a fifth aspect, the application provides a method for preparing the perovskite battery according to the fourth aspect, comprising the following steps:

[0023] The first hole transport layer is prepared on the conductive substrate by using nickel oxide;

[0024] A mixed solution of thiazole blue and carbazole self-assembled monomers is prepared, and the second hole transport layer is prepared by coating the mixed solution on the first hole transport layer;

[0025] The perovskite layer, the electron transport layer, the barrier layer and the electrode layer are sequentially prepared on the second hole transport layer to prepare the perovskite battery.

[0026] Compared with the conventional technology, the application has at least the following beneficial effects:

[0027] The application uses nickel oxide, thiazole blue and carbazole self-assembled monomers. The thiazole blue molecule has an extended π-conjugated structure, and can produce π-π interaction with the carbazole self-assembled monomers, so as to improve the uniformity of the SAM molecular arrangement, induce the formation of a more dense and flat interface monolayer, and at the same time, the amine group in the thiazole blue molecule and the N atom in the thiazole ring are combined with the nickel oxide, and selectively reduce the high-valence nickel, so as to passivate the interface traps between the nickel oxide and the perovskite, and improve the device performance. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to better describe and illustrate the embodiments or examples provided by the application, one or more drawings can be referred to. Additional details or examples used to describe the drawings should not be considered as limiting the scope of any one of the disclosed applications, the presently described embodiments or examples, and the best mode presently understood of these applications. Moreover, the same reference numbers are used to represent the same components throughout the drawings. In the drawings:

[0029] Figure 1 The J-V curve comparison chart of the perovskite battery in Example 2 and Comparative Example 1;

[0030] Figure 2 The J-V curve comparison chart of the perovskite battery in Example 2 and Comparative Example 2;

[0031] Figure 3 Figure for film contact angle test results of the second hole transport layer of Example 2 and Comparative Example 1;

[0032] Figure 4 Figure for device efficiency change curve of the perovskite cell of Example 2 and Comparative Example 1 after heating for 500 h. DETAILED DESCRIPTION

[0033] The embodiments and examples are further described below, which are only used to explain the present application and not intended to limit the scope of the present application. The purpose of providing the embodiments and examples is to make the disclosure of the present application more thoroughly understood. It should also be understood that the present application can be implemented in many different forms and is not limited to the embodiments and examples described herein. Those skilled in the art can make various modifications or changes without departing from the spirit and scope of the present application, and the equivalent forms obtained by the modifications or changes also fall within the protection scope of the present application. In addition, in the following description, a large number of specific details are given in order to provide a more complete understanding of the present application, and it should be understood that the present application can be implemented without one or more of these details.

[0034] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the present application belongs. The terminology used in the description of the present application herein only for the purpose of describing specific embodiments and is not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more of the associated listed items.

[0035] For the current perovskite cell, in the system of SAM modified nickel oxide layer, there is a problem that the SAM molecules are not arranged densely and uniformly on the surface of the nickel oxide, leading to the formation of island or aggregation structure, causing interface discontinuity and film defects, and there is significant interface recombination between the nickel oxide and the perovskite, affecting the device performance of the perovskite cell. In the present application, nickel oxide, thiazole blue and carbazole self-assembled monomers are used. The π-π interaction between the thiazole blue and carbazole self-assembled monomers can improve the uniformity of the arrangement of the SAM molecules, induce the formation of a more dense and flat interface monolayer, and the amine group in the thiazole blue molecule and the N atom in the thiazole ring are combined with the nickel oxide and selectively reduce the high valence state of the nickel, thereby passivating the interface traps between the nickel oxide and the perovskite, and improving the device performance.

[0036] In a first aspect, the present application provides a composite hole transport layer, comprising a first hole transport layer and a second hole transport layer;

[0037] The first hole transport layer comprises nickel oxide;

[0038] The second hole transport layer comprises thiazole blue and carbazole self-assembled monomers.

[0039] The present application introduces thiazole blue molecules into the SAM to form a blended precursor with the function of interface bridging agent. The thiazole blue molecules have extended π-conjugated structure and can form π-π interaction with the carbazole self-assembled monomers, which can alleviate the problem of uneven arrangement of SAM molecules, induce the formation of a more compact and flat hole transport layer, and the thiazole blue molecules have reversible redox behavior, the amine group in the thiazole blue and the N atom in the thiazole ring preferentially bind to oxidized nickel to selectively reduce high-valence nickel, thereby passivating the interface traps between the oxidized nickel and the perovskite, and improving the device performance.

[0040] In some embodiments, the mass ratio of the thiazole blue and the carbazole self-assembled monomers is 1:10-1:4, which can be 1:10, 1:9, 1:8, 1:7, 1:6.7, 1:6, 1:5 or 1:4.

[0041] In some embodiments, the carbazole self-assembled monomers comprise one or more of [2-(9H-carbazol-9-yl)ethyl]phosphonic acid, [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid, [2-(3,6-dimethyl-9H-carbazol-9-yl)ethyl]phosphonic acid, [4-(9H-carbazol-9-yl)ethyl]phosphonic acid, [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid, [4-(3,6-dimethoxy-9H-carbazol-9-yl)butyl]phosphonic acid, [4-(7H-dibenzo[c,e][1,2]oxazin-7-yl)butyl]phosphonic acid, [2-(9-bromocarbazol-9-yl)ethyl]phosphonic acid, [2-(9-chlorocarbazol-9-yl)ethyl]phosphonic acid, [4-(9-bromocarbazol-9-yl)butyl]phosphonic acid and [4-(9-fluorocarbazol-9-yl)butyl]phosphonic acid.

[0042] In some embodiments, the thickness of the first hole transport layer is 5nm-40nm, which can be 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm or 40nm; and the thickness of the second hole transport layer is 1nm-3nm, which can be 1nm, 2nm or 3nm.

[0043] In the second aspect, the present application provides a preparation method of the composite hole transport layer of the first aspect, comprising the following steps:

[0044] mixing the thiazole blue, the carbazole self-assembled monomers and the solvent to prepare a mixed solution;

[0045] coating the mixed solution on the first hole transport layer to prepare the second hole transport layer.

[0046] In some embodiments, the solvent comprises one or more of methanol, ethanol, isopropanol, and N,N-dimethylformamide.

[0047] In some embodiments, the preparation of the first hole transport layer comprises: using a method of coating a nickel oxide solution or magnetron sputtering nickel oxide to prepare the first hole transport layer.

[0048] In some embodiments, the preparation of the first hole transport layer comprises: using a method of coating a nickel oxide solution to prepare the first hole transport layer.

[0049] In the nickel oxide solution, the concentration of nickel oxide is 3 mg / mL-10 mg / mL, which can be 3 mg / mL, 4 mg / mL, 5 mg / mL, 6 mg / mL, 7 mg / mL, 8 mg / mL, 9 mg / mL, or 10 mg / mL.

[0050] In the nickel oxide solution, the solvent is a mixed solution of water and isopropanol; the volume ratio of water to isopropanol is 2-5:1, which can be 2:1, 3:1, 4:1, or 5:1.

[0051] The coating speed is 5 mm / s-15 mm / s, which can be 5 mm / s, 8 mm / s, 10 mm / s, 12 mm / s, or 15 mm / s.

[0052] After the step of coating the nickel oxide layer solution, an annealing step is further included, which comprises: an annealing temperature of 100°C-150°C, which can be 100°C, 110°C, 120°C, 130°C, 140°C, or 150°C; an annealing time of 8-15 min, which can be 8 min, 9 min, 10 min, 11 min, 12 min, 13 min, 14 min, or 15 min.

[0053] In some embodiments, in the step of preparing a mixed solution by mixing thiazole blue, carbazole self-assembled monomers, and a solvent, the solvent is ethanol; the concentration of thiazole blue is 0.04 mg / mL-0.1 mg / mL, which can be 0.04 mg / mL, 0.05 mg / mL, 0.06 mg / mL, 0.07 mg / mL, 0.08 mg / mL, 0.09 mg / mL, or 0.1 mg / mL; the concentration of carbazole self-assembled monomers is 0.15 mg / mL-0.4 mg / mL, which can be 0.15 mg / mL, 0.2 mg / mL, 0.25 mg / mL, 0.3 mg / mL, 0.35 mg / mL, or 0.4 mg / mL.

[0054] In some embodiments, the step of mixing the thiazole blue, the carbazole self-assembled monomer and the solvent to prepare the mixed solution specifically comprises: mixing the thiazole blue and the solvent to prepare a thiazole blue solution; mixing the carbazole self-assembled monomer and the solution to prepare a carbazole self-assembled monomer solution; and mixing the thiazole blue solution and the carbazole self-assembled monomer solution to prepare the mixed solution.

[0055] In some embodiments, the step of mixing the thiazole blue and the self-assembled monomer to prepare the mixed solution comprises:

[0056] mixing the thiazole blue and the solvent to prepare a thiazole blue solution, wherein the concentration of the thiazole blue is 0.08 mg / mL-0.2 mg / mL, which can be 0.08 mg / mL, 0.1 mg / mL, 0.12 mg / mL, 0.14 mg / mL, 0.16 mg / mL, 0.18 mg / mL or 0.20 mg / mL;

[0057] mixing the carbazole self-assembled monomer and the solution to prepare a carbazole self-assembled monomer solution, wherein the concentration of the carbazole self-assembled monomer is 0.3 mg / mL-0.8 mg / mL, which can be 0.3 mg / mL, 0.4 mg / mL, 0.5 mg / mL, 0.6 mg / mL, 0.7 mg / mL or 0.8 mg / mL;

[0058] mixing the thiazole blue solution and the carbazole self-assembled monomer solution at a volume ratio of 1:1 to prepare the mixed solution.

[0059] In some embodiments, in the step of coating the mixed solution on the first hole transport layer, the coating speed is 5 mm / s-15 mm / s, which can be 5 mm / s, 8 mm / s, 10 mm / s, 12 mm / s or 15 mm / s.

[0060] In some embodiments, after the step of coating the mixed solution on the first hole transport layer, the method further comprises an annealing step; the annealing step comprises: an annealing temperature of 80℃-120℃, which can be 80℃, 90℃, 100℃, 110℃ or 120℃; and an annealing time of 8-15 min, which can be 8 min, 9 min, 10 min, 11 min, 12 min, 13 min, 14 min or 15 min.

[0061] In a third aspect, the application provides a use of the composite hole transport layer of the first aspect or the composite hole transport layer prepared by the preparation method of the second aspect in a perovskite battery.

[0062] In a fourth aspect, the present application provides a perovskite cell, comprising a conductive substrate, a composite hole transport layer, a perovskite layer, an electron transport layer, a barrier layer and an electrode layer which are sequentially stacked.

[0063] The composite hole transport layer is the composite hole transport layer prepared by the preparation method of the composite hole transport layer in the second aspect or the composite hole transport layer in the third aspect.

[0064] The second hole transport layer is located between the first hole transport layer and the perovskite layer.

[0065] In the present application, thiazole blue molecules are introduced into the SAM to form a blended precursor with the function of an interface bridging agent. The thiazole blue molecules have an extended π-conjugated structure and can produce π-π interaction with the self-assembled monomolecular of carbazole, which can alleviate the problem of uneven arrangement of SAM molecules and induce the formation of a more compact and flat hole transport layer. In addition, the thiazole blue molecules have reversible redox behavior, and the amine group and the N atom in the thiazole ring of the thiazole blue molecules preferentially bind to the oxidized nickel in the first hole transport layer to selectively reduce the high-valence nickel, thereby passivating the interface traps between the first hole transport layer (oxidized nickel layer) and the perovskite layer.

[0066] In some embodiments, the conductive substrate comprises one of fluorine tin oxide transparent conductive glass (FTO), indium tin oxide transparent conductive glass (ITO), indium tin oxide / polyethylene terephthalate (ITO / PET) film, and indium tin oxide / polyethylene naphthalate (ITO / PEN) film.

[0067] In some embodiments, the electron transport layer comprises one or more of carbon 60 (C 60 ), [6,6]-phenyl C61 butyric acid methyl ester, and zinc oxide.

[0068] In some embodiments, the thickness of the electron transport layer is 10 nm-50 nm, which can be 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm or 50 nm.

[0069] In some embodiments, the barrier layer comprises 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) and / or tin dioxide (SnO2).

[0070] In some embodiments, the thickness of the barrier layer is 5 nm-20 nm, which can be 5 nm, 10 nm, 15 nm or 20 nm.

[0071] In some embodiments, the electrode layer comprises silver, copper, gold or carbon.

[0072] In some embodiments, the thickness of the electrode layer is 70-150 nm, which can be 70 nm, 80 nm, 90 nm, 100 nm, 110 nm, 120 nm, 130 nm, 140 nm or 150 nm.

[0073] In some embodiments, the perovskite layer comprises a compound represented by Formula 1:

[0074] ABX3 Formula 1;

[0075] wherein A is one or more of formamidinium cation (FA + ), methylamine cation (MA + ) and cesium ion (Cs + ); B is lead; and X is one or more of fluoride ion (F - ), chloride ion (Cl - ), bromide ion (Br - ) and iodide ion (I - ).

[0076] In some embodiments, the thickness of the perovskite layer is 200-900 nm, which can be 200 nm, 300 nm, 400 nm, 500 nm, 600 nm, 700 nm, 800 nm or 900 nm.

[0077] In some embodiments, the perovskite layer comprises Cs 0.12 FA 0.88 PbI3.

[0078] In the perovskite battery, the self-assembled monolayer is used to modify the interface of the perovskite battery. In addition to the problem that the arrangement of SAM molecules is not dense and uniform enough, which leads to the formation of island or aggregation structure, causes the interface to be discontinuous and the film to have defects, and affects the performance of the perovskite battery, the hole transport layer also has the problem that it cannot simultaneously optimize the interface defects of the double sides of the nickel oxide layer and the perovskite layer, and only passivating the interface on one side cannot fundamentally reduce the charge recombination of the whole device, thereby making it difficult to improve the performance of the device.

[0079] The present application uses thiazole blue and carbazole self-assembled monolayer as a composite material of the hole transport layer. The π-π interaction between the thiazole blue and the carbazole self-assembled monolayer improves the uniformity of the arrangement of SAM molecules, and induces the formation of a more dense and flat hole transport layer. In the composite hole transport layer, the amine group in the thiazole blue and the N atom in the thiazole ring preferentially bind to nickel in high valence state and selectively reduce it, thereby passivating the interface traps between the nickel oxide and the perovskite. At the same time, the sulfur atom in the thiazole ring of the thiazole blue faces the deep energy level trap state metal lead (Pb 0 ) in the perovskite, and the sulfur atom can oxidize Pb 0 to Pb2+ , inhibit the interface harmful reaction, while the sulfur atom faces the perovskite crystal and the interface, especially the unsaturated coordination of Pb in (100) crystal surface 2+ When, the sulfur atom as Lewis base can form coordination bond with these open Pb 2+ empty orbit, play a passivation perovskite function. Therefore, the thiazole blue can form a bifunctional passivation molecular bridge between the first hole transport layer (nickel oxide layer), the second hole transport layer and the perovskite layer, both facing the nickel oxide end, and facing the perovskite end, while also solving the problem of uneven arrangement of SAM molecules in the hole transport layer, significantly adjusting the perovskite cell bottom interface.

[0080] In a fifth aspect, the application provides a preparation method of the perovskite cell according to the fourth aspect, comprising the following steps:

[0081] Preparation of the first hole transport layer on the conductive substrate by using nickel oxide;

[0082] Preparation of a mixed solution of thiazole blue and carbazole self-assembled monomers, and coating the mixed solution on the first hole transport layer to prepare the second hole transport layer;

[0083] Preparation of a perovskite layer, an electron transport layer, a barrier layer and an electrode layer on the second hole transport layer in sequence to prepare the perovskite cell.

[0084] In some embodiments, before the step of preparing the first hole transport layer on the conductive substrate, the method further comprises a step of pretreating the conductive substrate, and the step of pretreating the transparent conductive substrate comprises: washing and treating the conductive substrate with ultraviolet ozone.

[0085] The washing treatment comprises one or more of detergent washing treatment, deionized water washing treatment, acetone washing treatment and isopropanol washing treatment.

[0086] In some embodiments, before the step of pretreating the conductive substrate, the method further comprises a step of P1 scribing; the step of P1 scribing uses nanosecond laser etching of the conductive substrate.

[0087] In some embodiments, the step of preparing the first hole transport layer on the conductive substrate comprises: using the method of coating nickel oxide solution or magnetron sputtering nickel oxide to prepare the first hole transport layer on the conductive substrate.

[0088] In some embodiments, the step of preparing the first hole transport layer on the conductive substrate comprises: preparing the first hole transport layer on the conductive substrate by using a method of coating a nickel oxide solution; the concentration of the nickel oxide in the nickel oxide solution is 3 mg / mL-10 mg / mL, which can be 3 mg / mL, 4 mg / mL, 5 mg / mL, 6 mg / mL, 7 mg / mL, 8 mg / mL, 9 mg / mL or 10 mg / mL;

[0089] The solvent in the nickel oxide solution is a mixed solution of water and isopropyl alcohol, and the volume ratio of the water and the isopropyl alcohol is 2-5:1, which can be 2:1, 3:1, 4:1 or 5:1;

[0090] The speed of coating is 5 mm / s-15 mm / s, which can be 5 mm / s, 8 mm / s, 10 mm / s, 12 mm / s or 15 mm / s;

[0091] After the step of coating the nickel oxide layer solution, the step of annealing is further included, and the step of annealing comprises: the temperature of annealing is 100°C-150°C, which can be 100°C, 110°C, 120°C, 130°C, 140°C or 150°C; the time of annealing is 8-15 min, which can be 8 min, 9 min, 10 min, 11 min, 12 min, 13 min, 14 min or 15 min.

[0092] In some embodiments, the solvent in the mixed solution of thiazole blue and carbazole self-assembled monomers includes one or more of methanol, ethanol, isopropyl alcohol and N,N-dimethylformamide.

[0093] In some embodiments, the solvent in the mixed solution of thiazole blue and carbazole self-assembled monomers is ethanol; the concentration of the thiazole blue is 0.04 mg / mL-0.1 mg / mL, which can be 0.04 mg / mL, 0.05 mg / mL, 0.06 mg / mL, 0.07 mg / mL, 0.08 mg / mL, 0.09 mg / mL or 0.1 mg / mL; and the concentration of the carbazole self-assembled monomers is 0.15 mg / mL-0.4 mg / mL, which can be 0.15 mg / mL, 0.2 mg / mL, 0.25 mg / mL, 0.3 mg / mL, 0.35 mg / mL or 0.4 mg / mL.

[0094] In some embodiments, the step of preparing the mixed solution of thiazole blue and carbazole self-assembled monomers specifically comprises: mixing the thiazole blue and the solvent to prepare a thiazole blue solution; mixing the carbazole self-assembled monomers and the solution to prepare a carbazole self-assembled monomer solution; and mixing the thiazole blue solution and the carbazole self-assembled monomer solution to prepare the mixed solution.

[0095] In some embodiments, the step of preparing a mixed solution of thiazole blue and carbazole self-assembled monomers includes:

[0096] thiazole blue and a solvent are mixed to prepare a thiazole blue solution, wherein the concentration of the thiazole blue is 0.08 mg / mL-0.2 mg / mL, which can be 0.08 mg / mL, 0.1 mg / mL, 0.12 mg / mL, 0.14 mg / mL, 0.16 mg / mL, 0.18 mg / mL or 0.20 mg / mL;

[0097] carbazole self-assembled monomers and a solvent are mixed to prepare a carbazole self-assembled monomer solution, wherein the concentration of the carbazole self-assembled monomers is 0.3 mg / mL-0.8 mg / mL, which can be 0.3 mg / mL, 0.4 mg / mL, 0.5 mg / mL, 0.6 mg / mL, 0.7 mg / mL or 0.8 mg / mL;

[0098] The thiazole blue solution and the carbazole self-assembled monomer solution are mixed in a volume ratio of 1:1 to prepare a mixed solution.

[0099] In some embodiments, the step of applying the mixed solution on the first hole transport layer to prepare a second hole transport layer includes: the mixed solution is applied on the first hole transport layer, annealing to prepare a second hole transport layer; the application speed is 5 mm / s-15 mm / s, which can be 5 mm / s, 8 mm / s, 10 mm / s, 12 mm / s or 15 mm / s; the annealing conditions include: temperature 80℃-120℃, which can be 80℃, 90℃, 100℃, 110℃ or 120℃; time 8-15 min, which can be 8 min, 9 min, 10 min, 11 min, 12 min, 13 min, 14 min or 15 min.

[0100] In some embodiments, the step of sequentially preparing a perovskite layer, an electron transport layer, a barrier layer and an electrode layer on the second hole transport layer includes:

[0101] a perovskite precursor solution is prepared, the perovskite precursor solution is applied on the second hole transport layer by using a slot coating process, and annealing is performed to prepare a perovskite layer;

[0102] thermal evaporation deposition C 60 is performed on the perovskite layer to prepare an electron transport layer;

[0103] atomic layer deposition is performed using tetrakis (dimethylamino) tin (TDMASn) and deionized water as precursors to deposit a tin dioxide film on the electron transport layer to prepare a barrier layer;

[0104] An electrode layer is prepared on the barrier layer by thermal evaporation deposition.

[0105] In some embodiments, the perovskite precursor solution comprises Cs 0.12 FA 0.88 PbI3, methylammonium chloride (MACI), and a solvent; the concentration of Cs 0.12 FA 0.88 The concentration of PbI3is 1M-1.5M, which can be 1M, 1.1M, 1.2M, 1.3M, 1.4M, or 1.5M; the concentration of methylammonium chloride (MACI) is 8mol%-12mol%, which can be 8mol%, 9mol%, 10mol%, 11mol%, or 12mol%; the solvent is a mixed solution of N,N-dimethylformamide (DMF) and N-methyl pyrrolidone (NMP); the volume ratio of DMF and NMP is 3-6:1, which can be 3:1, 4:1, 5:1, or 6:1. The introduction of methylammonium chloride (MACI) in the perovskite precursor solution can optimize the crystallization quality and morphology of the perovskite thin film.

[0106] The application can improve the wettability and flat spreading of the perovskite solution on the second hole transport layer by using thiazole blue, and promote perovskite crystallization.

[0107] In some embodiments, the conditions of the slot coating process include: the slot height is 60μm-180μm, which can be 60μm, 70μm, 80μm, 90μm, 100μm, 110μm, 120μm, 130μm, 140μm, 150μm, 160μm, 170μm, or 180μm; the coating speed is 3-10mm / s, which can be 3mm / s, 5mm / s, 8mm / s, or 10mm / s; the supply rate of the perovskite precursor solution is 4-10μL / s, which can be 4μL / s, 5μL / s, 7μL / s, or 10μL / s.

[0108] In some embodiments, in the step of coating the perovskite precursor solution on the hole transport layer and annealing to prepare the perovskite layer, the annealing temperature is 120℃-180℃, which can be 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, or 180℃; the annealing time is 8-15min, which can be 8min, 9min, 10min, 11min, 12min, 13min, 14min, or 15min.

[0109] In some embodiments, the thermal evaporation deposition C 60 The step of preparing the thin film layer includes: under room temperature conditions, depositing at a speed of 0.2Å / s under high vacuum conditions (5×10 -4Pa) depositing C by thermal evaporation 60 thin film layer.

[0110] In some embodiments, the step of preparing the barrier layer is followed by a step of performing P2 scribing; the P2 scribing is performed by a picosecond laser system.

[0111] In some embodiments, the step of preparing the barrier layer is followed by a step of performing P2 scribing; the P2 scribing is performed by a picosecond laser system.

[0112] In some embodiments, the step of preparing the electrode layer on the barrier layer by thermal evaporation includes: after the P2 scribing, depositing the electrode layer under high vacuum condition (5 x 10 -4 Pa) depositing the electrode layer by thermal evaporation, the electrode layer comprising copper.

[0113] In some embodiments, the step of preparing the electrode layer is followed by a step of packaging; the step of packaging includes: laminating packaging by using butyl glue and polyolefin elastomer (POE) film.

[0114] The embodiments of the present application will be described in detail below with reference to the examples. It should be understood that these examples are only used to illustrate the present application and not to limit the scope of the present application. The experimental methods in the following examples without specific conditions are preferred to refer to the guidance given in the present application, and can also be carried out according to the experimental manual or conventional conditions in the art, or according to the conditions suggested by the manufacturer, or according to the experimental methods known in the art.

[0115] Example 1

[0116] The preparation steps of the perovskite battery are as follows:

[0117] (1) Substrate treatment

[0118] First, a nanosecond laser is used to etch fluorine tin oxide transparent conductive glass (FTO) to form a P1 line, and then the FTO fluorine tin oxide transparent conductive glass is cleaned in an ultrasonic bath with detergent, deionized water, acetone and isopropanol for 15 min each, followed by 30 min of ultraviolet ozone treatment.

[0119] (2) Preparation of composite hole transport layer

[0120] Preparation of the first hole transport layer: 5 mg / mL of nickel oxide solution (solvent prepared by deionized water and isopropanol in a volume ratio of 3:1) is deposited on the substrate by coating, the coating height is 60 μm, the coating speed is 10 mm / s, and then annealed at 120°C for 10 min to prepare the first hole transport layer (thickness of 20 nm).

[0121] A second hole transport layer was prepared: a 0.8 mg / mL [4-(9H-carbazol-9-yl)ethyl] phosphonic acid (Me-4PACz) ethanol solution and a 0.08 mg / mL thiazole blue ethanol solution were mixed in a volume ratio of 1:1 to prepare a mixed solution containing 0.4 mg / mL [4-(9H-carbazol-9-yl)ethyl] phosphonic acid and 0.04 mg / mL thiazole blue, and the mixed solution was coated on the first hole transport layer (nickel oxide layer) at a coating height of 100 pm and a coating speed of 10 mm / s, and annealed at 100°C for 10 min to prepare a second hole transport layer (1 nm thick).

[0122] (3) Preparation of perovskite layer

[0123] A perovskite precursor solution containing 1.2 M Cs 0.12 FA 0.88 PbI3, 10 mol% MACl (0.12 M MACl) (solvent: DMF:NMP=4:1 (v:v)) was deposited on the second hole transport layer by a slot coating process, and the specific conditions of the slot coating process were as follows: the slot height was 120 pm, the coating speed was 5 mm / s, and the solution supply rate was 5 pL / s; the coated film was annealed at 150°C for 10 min to prepare a perovskite layer (500 nm thick).

[0124] (4) Preparation of electron transport layer

[0125] After cooling to room temperature, a 25 nm thick C -4 film was deposited on the perovskite layer by thermal evaporation under high vacuum conditions (5 x 10 60 Pa) at a rate of 0.2 Å / s to prepare an electron transport layer.

[0126] (5) Preparation of barrier layer

[0127] A 20 nm thick tin oxide film was deposited on the electron transport layer using an atomic layer deposition device using an aqueous solution of TDMASn as a precursor at 90°C to prepare a barrier layer. P2 scribing was performed on the tin oxide film using a picosecond laser system.

[0128] (6) Preparation of electrode layer

[0129] A 100 nm thick copper was deposited on the barrier layer by thermal evaporation under high vacuum conditions (5 x 10 -4 Pa), and P3 scribing was performed using a picosecond laser system.

[0130] (7) Encapsulation

[0131] Perovskite solar cells were fabricated by lamination encapsulation using butyl rubber and POE film.

[0132] Example 2

[0133] The preparation steps of the perovskite battery in Example 2 are basically the same as those in Example 1, except that the "0.08 mg / mL thiazolyl blue ethanol solution" is replaced with "0.12 mg / mL thiazolyl blue ethanol solution" to prepare a mixed solution containing 0.4 mg / mL of [4-(9H-carbazole-9-yl)ethyl]phosphonic acid and 0.06 mg / mL of thiazolyl blue.

[0134] Perovskite solar cells were prepared according to the method in Example 1.

[0135] Example 3

[0136] The preparation steps of the perovskite battery in Example 3 are basically the same as those in Example 1, except that the "0.08 mg / mL thiazolyl blue ethanol solution" is replaced with "0.16 mg / mL thiazolyl blue ethanol solution" to prepare a mixed solution containing 0.4 mg / mL of [4-(9H-carbazole-9-yl)ethyl]phosphonic acid and 0.08 mg / mL of thiazolyl blue.

[0137] Perovskite solar cells were prepared according to the method in Example 1.

[0138] Example 4

[0139] The preparation steps of the perovskite battery in Example 4 are basically the same as those in Example 1, except that "0.8 mg / mL of Me-4PACz ethanol solution and 0.08 mg / mL of thiazolyl blue ethanol solution" are replaced with "0.8 mg / mL of [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid (MeO-2PACz) ethanol solution and 0.20 mg / mL of thiazolyl blue ethanol solution" to prepare a mixed solution containing 0.4 mg / mL of [2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl]phosphonic acid and 0.1 mg / mL of thiazolyl blue.

[0140] Perovskite solar cells were prepared according to the method in Example 1.

[0141] Comparative Example 1

[0142] The preparation steps of the perovskite solar cell in Comparative Example 1 and Example 1 are basically the same, except that: thiazolyl blue is not added, and a mixed solution containing 0.4 mg / mL of [4-(9H-carbazole-9-yl)ethyl]phosphonic acid is used.

[0143] Perovskite solar cells were prepared according to the method in Example 1.

[0144] Comparative Example 2

[0145] Comparative Example 2 and Example 1 were substantially the same in the preparation steps of the perovskite cell, except that the second hole transport layer was not prepared.

[0146] A perovskite cell was prepared according to the method of Example 1.

[0147] Comparative Example 3

[0148] Comparative Example 3 and Example 1 were substantially the same in the preparation steps of the perovskite cell, except that the first hole transport layer was not prepared.

[0149] A perovskite cell was prepared according to the method of Example 1.

[0150] Comparative Example 4

[0151] Comparative Example 4 and Example 1 were substantially the same in the preparation steps of the perovskite cell, except that the first hole transport layer was not prepared; the mixed solution containing 0.4 mg / mL [4-(9H-carbazol-9-yl) ethyl] phosphonic acid was used instead of thiazole blue.

[0152] A perovskite cell was prepared according to the method of Example 1.

[0153] Test Example 1

[0154] (1) The perovskite cells prepared according to Examples 1-4 and Comparative Examples 1-4 were subjected to J-V test under AM1.5G standard solar light simulator, with the starting voltage set to 12 V, the cut-off voltage set to -0.1 V, and the scanning rate set to 100 mV / s. The test parameters included open circuit voltage (Voc), short circuit current (Jsc), fill factor (FF), and photoelectric conversion efficiency (PCE).

[0155] The test results are shown in Table 1 and Figures 1-2 . Figure 1 FIG. 1 is a comparative diagram of J-V curves of the perovskite cells in Example 2 and Comparative Example 1, Figure 2 FIG. 2 is a comparative diagram of J-V curves of the perovskite cells in Example 2 and Comparative Example 2.

[0156] Figures 1-2 The results of Table 1 and

[0157] Compared with Comparative Examples 1-2, the open circuit voltage, fill factor, and photoelectric conversion efficiency of Examples 1-4 were significantly improved.

[0158] The photoelectric conversion efficiency of Comparative Example 1 is 19.56%. Due to the modification of nickel oxide by carbazole self-assembled monolayer, the phosphonic acid group and N atom of the carbazole self-assembled monolayer can passivate the active high-valence nickel or shield the oxygen vacancy, thereby reducing the interface trap state density and improving the device efficiency. However, the passivation selection direction of the carbazole self-assembled monolayer is relatively single and limited, so the photoelectric conversion efficiency of the device of Comparative Example 1 is only 19.56%.

[0159] The photoelectric conversion efficiency of Comparative Example 2 is as low as 16.59% when the nickel oxide is not modified by thiazole blue and carbazole self-assembled monolayer. Compared with Comparative Example 2, the photoelectric conversion efficiency of Examples 1-3 is increased from 16.59% to 21.31%-22.01%, which is increased by 28.45%-32.67%. It can be seen that the use of carbazole self-assembled monolayer and thiazole blue as a composite material of the hole transport layer can significantly improve the photoelectric conversion efficiency of the perovskite battery and improve the device performance.

[0160] The photoelectric conversion efficiency of Comparative Example 3 is reduced to 18.85% when the first hole transport layer (nickel oxide layer) is not prepared. Compared with Comparative Example 3 without the first hole transport layer (nickel oxide layer), the photoelectric conversion efficiency of Example 1 is increased by 14%. This shows that the use of the first hole transport layer (nickel oxide layer) and the second hole transport layer including thiazole blue and carbazole self-assembled monolayer as a composite hole transport layer can significantly improve the photoelectric conversion efficiency of the perovskite battery and improve the device performance.

[0161] Comparing Examples 1-3 and Comparative Example 1, it can be seen that after adding thiazole blue to the carbazole self-assembled monolayer, the photoelectric conversion efficiency is more obviously improved. When the mass ratio of thiazole blue and carbazole self-assembled monolayer is 1:6.7 (Example 2), the photoelectric conversion efficiency of the perovskite battery is as high as 22.01%. This is due to the fact that thiazole blue molecules not only can have a synergistic effect with nickel oxide, but also can passivate defects in perovskite. The N atom in the amine group and the thiazole ring of thiazole blue preferentially binds to nickel oxide to selectively reduce high-valence Ni, thereby passivating the interface trap between nickel oxide and perovskite. The sulfur atom of the thiazole ring faces the deep level trap state metal lead (Pb 0 ) in perovskite, which can act as an electron acceptor to oxidize Pb 0 to Pb 2+ , inhibit the interface harmful reaction, and the sulfur atom faces the perovskite crystal and the interface, especially the unsaturated coordinated Pb 2+ in the (100) crystal face. The sulfur atom as a Lewis base (ligand) can form a coordination bond with these open Pb 2+ empty orbitals, which plays a role as a passivation agent.

[0162] Compared with the composite hole transport layer of Comparative Example 4 which only uses the carbazole self-assembled monolayer, the photovoltaic conversion efficiency of Comparative Example 1 is increased by 10% by using the first hole transport layer (nickel oxide layer); the photovoltaic conversion efficiency of Comparative Example 3 is increased by 6% by using the thiazole blue molecule; and the photovoltaic conversion efficiency of Example 1 is increased by 21% by using the thiazole blue molecule and the first hole transport layer (nickel oxide layer). It can be seen that the composite hole transport layer composed of the first hole transport layer (nickel oxide layer), the thiazole blue and the carbazole self-assembled monolayer can significantly improve the photovoltaic conversion efficiency of the perovskite battery and improve the performance of the device.

[0163] Table 1 J-V test results of perovskite batteries of Examples 1-4 and Comparative Examples 1-4

[0164]

[0165] (2) The contact angle test was performed on the substrate after the second hole transport layer was prepared in Example 2 and Comparative Example 1, and the results are shown in Figure 3 . Figure 3 FIG. 1 is a graph of the film contact angle test results of the second hole transport layer of Example 2 and Comparative Example 1.

[0166] Figure 3 The results show that, compared with Comparative Example 1 (contact angle 82.7°), the film of the second hole transport layer in Example 2 which uses the blended carbazole SAM and thiazole blue has a smaller contact angle (contact angle 63.4°), which can help the perovskite solution to spread better on the substrate, form a more uniform and continuous liquid film, and is conducive to the uniform distribution of perovskite crystal nuclei and the reduction of holes and island-shaped grains. This phenomenon is attributed to the extended π-conjugated structure of the thiazole blue molecule, which can produce π-π interaction with the carbazole SAM, alleviate the problem of uneven arrangement of SAM molecules, and induce the formation of a more dense and flat interface monolayer.

[0167] (3) The device heating aging test was performed in an air atmosphere. The perovskite batteries of Example 2 and Comparative Example 1 were placed on a metal heating plate maintained at 85°C, and a thermocouple connected to the metal plate was used to monitor and provide feedback control to the heating element to ensure temperature consistency. The J-V test was performed at intervals, and the ratio of the photovoltaic conversion efficiency after heating for 500h to the initial photovoltaic conversion efficiency was used as the device efficiency to reflect the battery life.

[0168] The results are shown in Figure 4 . Figure 4 FIG. 2 is a graph of the device efficiency change curve of the perovskite batteries of Example 2 and Comparative Example 1 after heating for 500h.

[0169] The results show that after heating aging for 500 hours, the relative efficiency of Example 2 decreases to 92.58% compared with the original PCE, while the relative efficiency of Comparative Example 1 decreases to 65.00%, the efficiency retention rate of the device of Example 2 is significantly higher than that of Comparative Example 1, which is attributed to the introduction of thiazole blue molecules in Example 2, which effectively passivates the defects of nickel oxide and perovskite crystals, inhibits the non-radiative recombination at the multi-layer interface of the first hole transport layer (nickel oxide layer), the second hole transport layer and the perovskite layer, and improves the stability of the multi-layer interface of the nickel oxide layer, the second hole transport layer and the perovskite layer in multiple dimensions.

[0170] Each technical feature of the above-described embodiments can be combined arbitrarily, and for the sake of brevity, each technical feature of the above-described embodiments is not described in all possible combinations, but it should be considered that any combination of these technical features is within the scope of the present disclosure, as long as the combination does not contradict.

[0171] The above-described embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent application. It should be pointed out that for ordinary skilled persons in the art, several modifications and improvements can be made without departing from the concept of the present application, and these are within the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A composite hole transport layer, characterized by, The first hole transport layer and the second hole transport layer are included. The first hole transport layer includes nickel oxide. The second hole transport layer includes thiazole blue and a carbazole self-assembly monomer.

2. The composite hole transport layer according to claim 1, wherein The mass ratio of the thiazole blue and the carbazole self-assembly monomer is 1:10-1:

4.

3. The composite hole transport layer according to claim 1, wherein The carbazole self-assembly monomer includes one or more of [2-(9H-carbazol-9-yl)ethyl]phosphonic acid, [2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic acid, [2-(3,6-dimethyl-9H-carbazol-9-yl)ethyl]phosphonic acid, [4-(9H-carbazol-9-yl)ethyl]phosphonic acid, [4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid, [4-(3,6-dimethoxy-9H-carbazol-9-yl)butyl]phosphonic acid, [4-(7H-dibenzo[c,e][1,2]oxazin-7-yl)butyl]phosphonic acid, [2-(9-bromocarbazol-9-yl)ethyl]phosphonic acid, [2-(9-chlorocarbazol-9-yl)ethyl]phosphonic acid, [4-(9-bromocarbazol-9-yl)butyl]phosphonic acid, and [4-(9-fluorocarbazol-9-yl)butyl]phosphonic acid.

4. The composite hole transport layer according to any one of claims 1 to 3, wherein, The thickness of the first hole transport layer is 5-40 nm, and the thickness of the second hole transport layer is 1-3 nm.

5. The method of claim 1 to 4, wherein the composite hole transport layer is prepared by the steps of: The method includes the following steps: A mixed solution is prepared by mixing thiazole blue, a carbazole self-assembly monomer, and a solvent. The mixed solution is coated on the first hole transport layer to prepare the second hole transport layer.

6. The method of claim 5, wherein the compound hole transport layer is prepared by mixing the compound hole transport material with a solvent. The solvent includes one or more of methanol, ethanol, isopropanol, and N,N-dimethylformamide.

7. The composite hole transport layer of any one of claims 1-4 or the composite hole transport layer prepared by the method of any one of claims 5-6 is applied in a perovskite battery.

8. A perovskite cell characterized by, The perovskite battery includes an electrically conductive substrate, a composite hole transport layer, a perovskite layer, an electron transport layer, a barrier layer, and an electrode layer which are sequentially stacked. The composite hole transport layer is the composite hole transport layer of any one of claims 1-4 or the composite hole transport layer prepared by the method of any one of claims 5-6. The second hole transport layer is located between the first hole transport layer and the perovskite layer.

9. The perovskite cell according to claim 8, characterized in that, The perovskite layer includes a compound shown in Formula 1: ABX3 Formula 1 A is one or more of formamidinium cation, methylamine cation, and cesium ion; B is lead; and X is one or more of fluoride ion, chloride ion, bromide ion, and iodide ion.

10. The method for preparing a perovskite solar cell as described in claim 8 or 9, characterized in that, The method includes the following steps: The first hole transport layer is prepared on the electrically conductive substrate by using nickel oxide. A mixed solution of thiazole blue and a carbazole self-assembly monomer is prepared, and the mixed solution is coated on the first hole transport layer to prepare the second hole transport layer. A perovskite layer, an electron transport layer, a barrier layer, and an electrode layer are sequentially prepared on the second hole transport layer to prepare the perovskite battery.

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