Interface layer of perovskite battery, perovskite battery and preparation method of perovskite battery

Abstract

The invention relates to the technical field of perovskite battery preparation, in particular to an interface layer of a perovskite battery, the perovskite battery and a preparation method of the perovskite battery. The interface layer is obtained by reacting diamine molecules and 1, 3, 5-benzoyl chloride in a molar concentration ratio of 1: (1.5-2.5). According to the invention, diamine molecules and 1, 3, 5-benzoyl chloride are subjected to an in-situ polymerization reaction on the surface of perovskite to generate an interface layer, so that the surface of a perovskite film is not damaged, interface contact between perovskite and a fullerene electron transport layer can be improved, energy level arrangement can be optimized, defects on the surface of the perovskite can be passivated by using self functional groups, and the performance of the perovskite film is improved. And the battery performance is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of perovskite solar cell preparation, and specifically to an interface layer of a perovskite solar cell, a perovskite solar cell and a preparation method thereof. Background Art

[0002] After only more than a decade of development, the photoelectric conversion efficiency of single-junction perovskite solar cells has increased from the initial 3.8% to 26.7%, approaching the level of single-crystalline silicon solar cells and exceeding thin-film solar cells such as polycrystalline silicon, cadmium telluride, and copper indium gallium selenide. However, there is still a large gap from its theoretical limit efficiency (>31%, 1.55 eV). The rapid increase in efficiency benefits from the continuous improvement of perovskite thin film preparation level and the innovation of new and efficient charge transport materials. With the continuous breakthrough in the research of new and efficient hole transport layer materials, and the fact that fullerene-based electron transport layer materials have high electron mobility and high thermal stability (such as PCBM, C60, etc.), especially C60 can meet the requirements of preparing uniform large-area devices by thermal evaporation, the inverted perovskite solar cells based on fullerene-based electron transport layers have gradually become a research hotspot, and both the conversion efficiency and stability have been greatly improved.

[0003] However, there is a large energy level mismatch problem between the perovskite light-absorbing layer and the fullerene-based electron transport layer, and the HOMO (highest occupied molecular orbital) energy level of the fullerene-based electron transport layer has a small energy level difference from the perovskite energy level, resulting in serious carrier recombination loss at the perovskite light-absorbing layer / electron transport layer interface. In addition, there are a large number of growth defects on the perovskite surface, which greatly limits the development of inverted perovskite solar cells based on fullerene-based electron transport layers (such as C60). Therefore, it is urgent to develop an interface passivation layer material or passivation strategy that is universal for the perovskite system, has a strong binding force, and can prevent the direct contact between the perovskite and the fullerene-based electron transport layer. Summary of the Invention

[0004] In order to solve the defects existing in the prior art, the present invention provides an interface layer of a perovskite solar cell, a perovskite solar cell and a preparation method thereof. The present invention generates an interface layer by in-situ polymerization reaction of diamine molecules and TMC on the surface of perovskite, which not only does not damage the surface of the perovskite thin film, but also improves the interface contact between the perovskite and the fullerene-based electron transport layer, optimizes the energy level arrangement, and can passivate the defects on the perovskite surface by using its own functional groups to improve the battery performance.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] In the first aspect, the present invention provides an interface layer of a perovskite solar cell, and the interface layer is obtained by reacting diamine molecules and 1,3,5-benzenetricarbonyl chloride with a molar concentration ratio of 1:(1.5 - 2.5).

[0007] Among them, the diamine molecule is any molecule containing two amino groups, and its structure is variable, including carbon skeleton types (such as alkyl chain type, rigid phenyl-fused ring organic compounds, and their phenyl derivatives, etc.) and functional group types (such as sulfhydryl group, mercapto group, phosphino group, cyano group, carbonyl group, etc.).

[0008] Preferably, the diamine molecule is selected from any one or more of 1,3-propanediamine, methylenediamine, 1,2-diaminoethane, 1,4-diaminobutane, 1,4-diaminobenzene, 2,6-diaminonaphthalene, 2,6-diaminoanthracene, 1,6-diaminopyrene, 4,4'-diaminodiphenyl sulfide, 2,2'-diaminodiphenyl disulfide, bis(aminophenyl)-18-crown-6 ether.

[0009] Preferably, the chemical structural formula of the diamine molecule is selected from any one of the following formulas 1 to 11:

[0010]

[0011] Preferably, the reaction temperature is room temperature.

[0012] Preferably, the compound obtained by the reaction is a polyamide compound.

[0013] Preferably, the polyamide compound has a two-dimensional network structure.

[0014] In a second aspect, the present invention provides a perovskite solar cell comprising the above interface layer.

[0015] Preferably, the structure of the perovskite solar cell further includes a conductive glass substrate, a hole transport layer, a perovskite light-absorbing layer, an electron transport layer, and a top electrode.

[0016] Preferably, the conductive glass substrate includes fluorine-doped tin dioxide (FTO) and / or indium tin oxide (ITO).

[0017] Preferably, the hole transport layer is selected from any one or more of metal oxides (such as nickel oxide, etc.), self-assembled monolayers (such as 2PACz, MeO-2PACz, 4PADCB). Deposition can be carried out by processes such as magnetron sputtering, electron beam evaporation, spraying, spin coating, etc.

[0018] Preferably, the perovskite light-absorbing layer uses a material with the ABX 3 structure, wherein A is a monovalent cation, including but not limited to rubidium Rb + , sodium Na + , potassium K + , cesium Cs + , formamidine HN=CHNH 3 + (FA), methylamine CH3 NH 3 + (MA) or a combination thereof; B is a divalent cation, including but not limited to tin Sn 2+ , lead Pb 2+ or a combination thereof; X is a monovalent anion, including but not limited to halogen anions (chlorine Cl - , bromine Br - , iodine I - ) pseudo-halide ions (thiocyanate ion SCN - etc.) or a combination thereof. The perovskite light-absorbing layer can be deposited by means such as slit coating, blade coating, vacuum evaporation, flash evaporation, spin coating, etc.

[0019] Preferably, the material of the charge transport layer includes C60, PCBM, PC61BM, titanium oxide TiO 2 , tin oxide SnO 2 , niobium oxide Nb 2 O 5 Any one or several of them. It can be obtained by means such as vacuum evaporation, electron beam evaporation, atomic layer deposition (ALD), spin coating, etc.

[0020] Preferably, the top electrode includes but is not limited to transparent conductive oxides (FTO, ITO, etc.), metals (gold Au, silver Ag, copper Cu, etc.) or a combination thereof.

[0021] Preferably, the structure of the perovskite battery further includes a blocking layer.

[0022] Preferably, the blocking layer includes but is not limited to SnO 2 , bathocuproine (BCP), etc.

[0023] Preferably, the perovskite battery of the present invention is a reverse perovskite solar cell.

[0024] In a third aspect, the present invention provides a method for preparing a perovskite battery, including the following steps:

[0025] Clean the conductive glass, prepare the hole transport layer, prepare the perovskite light-absorbing layer, prepare the interface layer, prepare the electron transport layer, prepare the top electrode; wherein, the process of preparing the interface layer is: successively coat a diamine molecule and 1,3,5-benzenetricarbonyl chloride on the surface of the perovskite light-absorbing layer to obtain it.

[0026] Preferably, the molar concentration ratio of the diamine molecule to 1,3,5-benzenetricarbonyl chloride is 1:(1.5 - 2.5).

[0027] Preferably, the diamine molecule is selected from any one of 1,3-propanediamine, methylenediamine, 1,2-diaminoethane, 1,4-diaminobutane, 1,4-diaminobenzene, 2,6-diaminonaphthalene, 2,6-diaminoanthracene, 1,6-diaminopyrene, 4,4'-diaminodiphenyl sulfide, 2,2'-diaminodiphenyl disulfide, and bis(aminophenyl)-18-crown-6 ether.

[0028] Preferably, the preparation method further includes preparing a barrier layer.

[0029] The beneficial effects of the present invention are as follows:

[0030] Currently, most in-situ polymerization modification strategies involve adding reactive monomer molecules to the perovskite precursor solution and in-situ generating polymers during the annealing process to fill grain boundaries, etc. However, the in-situ polymerization reaction of the present invention occurs on the surface of the perovskite and can react at room temperature, and a polymer film can be rapidly formed without an additional annealing step. The present invention constructs a polymer framework through the rapid cross-linking reaction of diamine molecules and 1,3,5-benzenetricarbonyl chloride (TMC) molecules at room temperature to form a two-dimensional network polyamide film (PAN). On the one hand, it can improve the energy level matching between the perovskite light-absorbing layer and the fullerene-based electron transport layer, promote the transport of carriers, and inhibit non-radiative recombination; on the other hand, it can passivate surface defects of the perovskite, such as uncoordinated lead ions, etc., by using different functional groups of the polymer, such as amide groups, amino groups, etc.; in addition, it can also reduce the direct contact between the fullerene-based electron transport layer and the perovskite, reduce contact loss, and extend the service life of the battery. Description of the Drawings

[0031] Figure 1 It is a diagram of the solution state before and after the reaction of 1,3-propanediamine (PDA) and 1,3,5-benzenetricarbonyl chloride (TMC);

[0032] Figure 2 It is a structural diagram of the perovskite battery of the present invention;

[0033] Figure 3 It is a morphological characterization diagram of the perovskite light-absorbing layer, pure PDA film, TMC film, and polyamide film;

[0034] Figure 4 It is a J-V curve diagram of the perovskite battery obtained with different interface layers;

[0035] Figure 5 It is an XRD diagram of the perovskite film with and without polyamide interface modification under different conditions;

[0036] Figure 6 It is a J-V curve diagram of the perovskite battery obtained in Examples 1 to 3. Detailed Embodiments

[0037] To enable those skilled in the art to better understand the technical solution of the invention, the following further detailed description of the present invention will be given in conjunction with specific embodiments.

[0038] Example 1

[0039] The raw materials of the interfacial layer of the perovskite solar cell provided in this example are 0.5 mM of 1,3-propanediamine (PDA) and 1 mM of 1,3,5-benzenetricarbonyl chloride (TMC). The two rapidly crosslink at room temperature to form a two-dimensional network polyamide film (PAN). The reaction principle is as follows:

[0040]

[0041] For the comparison of the solution states of the raw materials and products before and after the reaction, see Figure 1 , it can be seen that the raw materials can react at room temperature, generating white floccules and releasing HCl gas.

[0042] The structure of the perovskite solar cell in this example is as Figure 2 shown, including a conductive glass substrate, a hole transport layer (4PADCB), a perovskite light-absorbing layer (Rb 0.05 Cs 0.05 MA 0.05 FA 0.85 Pb(I 0.95 Br 0.05 ) 3 )), an interfacial layer (prepared from PDA and TMC as raw materials), an electron transport layer (C60), and a top electrode (silver electrode). The above-mentioned structural layers in this example are arranged from bottom to top, being a reverse perovskite solar cell.

[0043] This example also provides a preparation method of a perovskite solar cell, including the following steps:

[0044] 1. The conductive glass substrate (FTO or ITO) is ultrasonically cleaned with a cleaning agent, deionized water, acetone, and isopropyl alcohol in sequence for 20 minutes, and then dried for standby.

[0045] 2. After the cleaned conductive glass substrate is cleaned with ultraviolet-ozone for 15 minutes, it is immediately transferred into a vacuum glove box, and an ethanol solution of 4PADCB (concentration: 0.3 - 0.5 mg mL -1 ) is spin-coated on the substrate surface. After the spin-coating is completed, it is immediately transferred to a hot stage at 100 °C for annealing for 10 min to serve as the hole transport layer.

[0046] 3. Prepare the perovskite light-absorbing layer (1.5 M of Rb 0.05 Cs 0.05 MA 0.05 FA 0.85 Pb(I0.95 Br 0.05 ) 3 ):Dissolve MABr, FAI, CsI, RbI, PbBr 2 , PbI 2 in a DMF / DMSO (V / V = 4 / 1) mixed solution, stir evenly and filter for standby to obtain a perovskite precursor solution; then spin-coat the perovskite precursor solution onto the surface of the hole transport layer with spin-coating parameters of 1000 rmp for 10 s and 3000 rmp for 40 s. Add 100 μl of chlorobenzene antisolvent 15 s before the end of the second spin-coating. Immediately transfer it to a hot plate at 100 °C for annealing for 10 min after spin-coating, and cool to room temperature for standby.

[0047] 4. Preparation of the interfacial layer: First, spin-coat a 0.5 mM 1,3-propanediamine (PDA) solution (dissolved in isopropanol) on the surface of the perovskite light-absorbing layer without annealing; then spin-coat a 1 mM 1,3,5-benzenetricarbonyl chloride (TMC) solution (dissolved in isopropanol) on the surface of PDA; to eliminate the residual solvent, anneal on a hot plate at 80 °C for 5 min after spin-coating.

[0048] 5. Evaporate 15 - 30 nm of C60 and 5 - 8 nm of BCP on the surface of the interfacial layer in sequence by vacuum thermal evaporation to obtain the electron transport layer and the blocking layer respectively.

[0049] 6. After evaporation, transfer all the thin films into the metal evaporation chamber, and evaporate a silver electrode of 100 - 150 nm on the surface of the device under a low vacuum condition of less than 5×10 -4 Pa.

[0050] Morphology and performance tests:

[0051] (1) Morphology characterization

[0052] Using the perovskite light-absorbing layer as the substrate, prepare pure PDA thin film, TMC thin film and polyamide thin film on the perovskite light-absorbing layer respectively according to the parameters in step 4 above, and perform SEM characterization. See Figure 3 (In the figure, PVK is the abbreviation of "perovskite"). It can be seen that the PDA, TMC and the polymer thin film formed by the two do not affect the surface morphology of the perovskite light-absorbing layer, and the polymer mainly aggregates at the grain boundaries of the perovskite, fills the grain boundaries, reduces the surface roughness, and improves the contact between the perovskite and the electron transport layer C60.

[0053] (2) Battery performance test

[0054] The present invention compares the performance of perovskite solar cells when the interfacial layer materials are pure PDA thin film, TMC thin film and polyamide thin film respectively through J-V curves. See Figure 4, the J-V curve is an important criterion for measuring the performance of the device. As can be seen from the figure, compared with the single spin-coated PDA and TMC films, the polyamide interfacial layer has a more obvious effect on improving the device performance, especially V OC and FF. The specific results are shown in Table 1, indicating that the polyamide interface significantly improves the contact between perovskite and C60, reduces the interfacial recombination loss, optimizes the energy level alignment, and significantly enhances the device performance.

[0055] Table 1

[0056]

[0057]

[0058] J SC : short-circuit current density; V OC : open-circuit voltage; FF: fill factor; PCE: power conversion efficiency

[0059] (3) XRD characterization

[0060] The present invention monitored the changes in the XRD peak patterns of perovskite films with and without polyamide interface modification before and after 550 h at different conditions. As Figure 5 shown, for the two films in the room-temperature air environment and nitrogen environment, the changes before and after were negligible; the changes were more obvious under the conditions of heating at 60 °C and light illumination in the nitrogen environment. After storing for 550 h under heating or light illumination conditions, the characteristic peak of lead iodide at about 12.7° was more obvious for the perovskite film without polyamide interface layer modification, indicating that the perovskite decomposed during storage. However, there was no obvious lead iodide peak precipitation for the perovskite film modified with the polyamide interface during storage, indicating that the polyamide interface can significantly inhibit the perovskite decomposition, enhance the stability of the perovskite, and extend the service life of the perovskite solar cell.

[0061] Example 2

[0062] Same as Example 1, the difference is only that the raw materials of the interfacial layer of the perovskite cell are 0.5 mM of 1,3-propanediamine (PDA) and 0.75 mM of 1,3,5-benzenetricarbonyl chloride (TMC).

[0063] Example 3

[0064] Same as Example 1, the difference is only that the raw materials of the interfacial layer of the perovskite cell are 0.5 mM of 1,3-propanediamine (PDA) and 1.25 mM of 1,3,5-benzenetricarbonyl chloride (TMC).

[0065] The J-V curve diagrams of the perovskite cells obtained in Examples 1 to 3 are shown in Figure 6 , and the specific results are shown in Table 2.

[0066] Table 2

[0067]

[0068]

[0069] Example 4

[0070] Same as Example 1, the only difference is that in the preparation process of the perovskite battery, the preparation process of the blocking layer in Step 5 is as follows: deposit 5 - 30 nm of SnO on the surface of C60 by atomic layer deposition (ALD). 2 .

[0071] Example 5

[0072] Same as Example 1, the only difference is that Step 3 in the preparation process of the perovskite battery is as follows:

[0073] Prepare the perovskite light - absorbing layer (1.67 M of Cs 0.05 MA 0.1 FA 0.85 PbI 3 ): Dissolve MAI, FAI, CsI, MACl, PbI 2 in a DMF / DMSO mixed solution, stir evenly and filter for later use; then spin - coat the perovskite precursor solution onto the surface of the hole - transporting layer at 1000 rmp for 10 s and 5000 rmp for 35 s. Add 120 μl of chlorobenzene antisolvent 15 s before the end of the second spin - coating. Immediately transfer to a hot plate at 120 °C for annealing for 10 min after spin - coating, and cool to room temperature for later use.

[0074] Example 6

[0075] Same as Example 1, the only difference is that the raw materials of the interface layer of the perovskite battery provided in this example are methylenediamine and 1,3,5 - benzenetricarbonyl chloride (TMC), and the reaction principle and effect are the same as those shown in Example 1.

[0076] The structural formula of methylenediamine is:

[0077] Example 7

[0078] Same as Example 1, the only difference is that the raw materials of the interface layer of the perovskite battery provided in this example are 1,2 - diaminoethane and 1,3,5 - benzenetricarbonyl chloride (TMC), and the reaction principle and effect are the same as those shown in Example 1.

[0079] The structural formula of 1,2 - diaminoethane is:

[0080] Example 8

[0081] Same as Example 1, with the only difference being that the raw materials of the interfacial layer of the perovskite cell provided in this example are 1,4-diaminobutane and 1,3,5-benzenetricarbonyl chloride (TMC), and the reaction principle and effects are the same as those shown in Example 1.

[0082] The structural formula of 1,4-diaminobutane is:

[0083] Example 9

[0084] Same as Example 1, with the only difference being that the raw materials of the interfacial layer of the perovskite cell provided in this example are 1,4-diaminobenzene and 1,3,5-benzenetricarbonyl chloride (TMC), and the reaction principle and effects are the same as those shown in Example 1.

[0085] The structural formula of 1,4-diaminobenzene is:

[0086] Example 10

[0087] Same as Example 1, with the only difference being that the raw materials of the interfacial layer of the perovskite cell provided in this example are 2,6-diaminonaphthalene and 1,3,5-benzenetricarbonyl chloride (TMC), and the reaction principle and effects are the same as those shown in Example 1.

[0088] The structural formula of 2,6-diaminonaphthalene is:

[0089] Example 11

[0090] Same as Example 1, with the only difference being that the raw materials of the interfacial layer of the perovskite cell provided in this example are 2,6-diaminoanthracene and 1,3,5-benzenetricarbonyl chloride (TMC), and the reaction principle and effects are the same as those shown in Example 1.

[0091] The structural formula of 2,6-diaminoanthracene is:

[0092] Example 12

[0093] Same as Example 1, with the only difference being that the raw materials of the interfacial layer of the perovskite cell provided in this example are 1,6-diaminopyrene and 1,3,5-benzenetricarbonyl chloride (TMC), and the reaction principle and effects are the same as those shown in Example 1.

[0094] The structural formula of 1,6-diaminopyrene is:

[0095] Example 13

[0096] Same as Example 1, with the only difference being that the raw materials of the interfacial layer of the perovskite cell provided in this example are 4,4'-diaminodiphenyl sulfide and 1,3,5-benzenetricarbonyl chloride (TMC), and the reaction principle and effects are the same as those shown in Example 1.

[0097] The structural formula of 4,4'-diaminodiphenyl sulfide is:

[0098] Example 14

[0099] Same as Example 1, the only difference is that the raw materials of the interfacial layer of the perovskite battery provided in this example are 2,2'-diaminodiphenyl disulfide and 1,3,5-benzenetricarbonyl chloride (TMC), and the reaction principle and effect are the same as those shown in Example 1.

[0100] The structural formula of 4,4'-diaminodiphenyl sulfide is:

[0101] Example 15

[0102] Same as Example 1, the only difference is that the raw materials of the interfacial layer of the perovskite battery provided in this example are bis(aminophenyl)-18-crown-6 ether and 1,3,5-benzenetricarbonyl chloride (TMC), and the reaction principle and effect are the same as those shown in Example 1.

[0103] The structural formula of bis(aminophenyl)-18-crown-6 ether is:

[0104]

[0105] The above are only the preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limitations on the present invention. The protection scope of the present invention should be subject to the scope defined by the claims. For those of ordinary skill in the art, without departing from the spirit and scope of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as within the protection scope of the present invention.

Claims

1. An interface layer of a perovskite battery, characterized in that: The interface layer is obtained by reacting diamine molecules with a molar concentration ratio of 1:(1.5-2.5) and 1,3,5-benzenetricarboxylic acid chloride.

2. The interface layer of the perovskite battery according to claim 1, characterized in that: The diamine molecule is selected from any one or more of 1,3-propylenediamine, methylenediamine, 1,2-diaminoethane, 1,4-diaminobutane, 1,4-diaminobenzene, 2,6-diaminonaphthalene, 2,6-diaminoanthracene, 1,6-diaminopyrene, 4,4'-diaminodiphenyl sulfide, 2,2'-diaminodiphenyl disulfide, and bis(aminophenyl)-18-crown 6 ether.

3. The interface layer of the perovskite battery according to claim 1 or 2, characterized in that: The chemical structural formula of the diamine molecule is selected from any one of the following formulas 1 to 11:

4. The interface layer of the perovskite battery according to claim 1, characterized in that: The compound obtained by the reaction is a polyamide compound.

5. A perovskite battery, characterized in that: The invention comprises the interface layer according to any one of claims 1 to 4.

6. The perovskite battery according to claim 5, characterized in that: The structure of the perovskite cell also includes a conductive glass substrate, a hole transport layer, a perovskite light absorption layer, an electron transport layer and a top electrode.

7. The perovskite cell according to claim 6, characterized in that: The material of the charge transport layer includes any one or more of C60, PCBM, PC61BM, titanium oxide TiO2, tin oxide SnO2, and niobium oxide Nb2O5.

8. The perovskite battery according to any one of claims 5 to 7, characterized in that: The structure of the perovskite cell also includes a barrier layer.

9. A method for preparing a perovskite battery, characterized in that: The following steps are involved: The conductive glass is cleaned, a hole transport layer is prepared, a perovskite light absorbing layer is prepared, an interface layer is prepared, an electron transport layer is prepared, and a top electrode is prepared; wherein, the process of preparing the interface layer is: coating diamine molecules and 1,3,5-benzenetricarboxylic acid chloride on the surface of the perovskite light absorbing layer in sequence.

10. The preparation method according to claim 9, characterized in that: The molar concentration ratio of the diamine molecule to 1,3,5-benzenetricarboxylic acid chloride is 1:(1.5-2.5).

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