Non-fullerene material doped perovskite solar cell and preparation method thereof

Abstract

The invention discloses a high-efficiency non-fullerene material-doped PCBM perovskite solar cell and a preparation method thereof, and the solar cell sequentially comprises an ITO conductive glass substrate layer, a hole transport layer MeO-4PACz, a perovskite layer Cs0.05 (FA0.95 MA0.05) 0.95 Pb (I0.95 Br0.05) 3, a passivation layer PEAI, an n-type non-fullerene material eC9-2Cl and [6, 7]-bis (4-chlorophenyl)-1, 2, 3, 4, 5, 6, 7, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8 the electron transport layer PCBM + eC9-2Cl, the 2, 9-dimethyl-4, 7-biphenyl-1, 10-phenanthrene hole blocking layer BCP and the metal Ag electrode layer are formed by mixing the 2, 9-dimethyl-4, 7-biphenyl-1, 10-phenanthrene hole blocking layer, the 2, 9-dimethyl-4, 7-biphenyl-1, 10-phenanthrene hole blocking layer and the 2, 9-dimethyl-4, 7-biphenyl-1, 10-phenanthrene hole blocking layer. According to the scheme, the non-fullerene material is introduced into the PCBM layer, so that non-coordinated iodide ions are effectively reduced to passivate defects, additional light-induced absorption is brought, energy level matching and conductivity are improved, the surface appearance is improved, ion migration is inhibited, and the stability of the device is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of solar cells, and particularly relates to a perovskite solar cell doped with non-fullerene materials and a preparation method thereof. Background Art

[0002] Photovoltaic power generation has experienced rapid progress and has become a key energy pillar. In order to overcome the problems of high energy consumption and limited energy conversion efficiency in the production process of traditional silicon-based solar cells and promote a revolutionary leap in photovoltaic power generation technology, innovative photovoltaic technologies such as perovskite solar cells are becoming the focus of research.

[0003] As the third-generation solar cell, perovskite solar cells have achieved a photoelectric conversion efficiency of more than 26% in just sixteen years. Compared with other solar cells, perovskite solar cells have the advantages of low cost and simple preparation process, and have broad future prospects. However, problems such as device instability, serious energy loss in the electron transport layer, and defect passivation severely restrict the further improvement of its performance. In addition, the doping of fullerene materials in perovskite or the transport layer has been described in many literatures to improve the performance of the perovskite layer or the transport layer. However, fullerene doping can only optimize local interface characteristics and is difficult to synergistically regulate the defects of the perovskite bulk phase and the charge transport layer, resulting in limited carrier transport and collection efficiency and restricting the breakthrough of the overall device performance. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a perovskite solar cell doped with non-fullerene materials. By introducing non-fullerene materials into the electron transport layer, multi-dimensional regulation is achieved, enabling it to have advantages such as additional photoinduced absorption, improved film morphology, inhibition of ion migration, improved charge transport, and high stability.

[0005] In order to achieve the above technical effects, the present invention is realized through the following technical solutions: A perovskite solar cell doped with non-fullerene materials, characterized in that it sequentially includes an ITO conductive glass layer, a hole transport layer MeO-4PACz of (2-(3,6-dimethyl-9H-carbazol-9-yl)butyl)phosphonic acid, a perovskite layer Cs 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3, a passivation layer PEAI, an electron transport layer PCBM+eC9-2Cl formed by blending non-fullerene material eC9-2Cl and [6,6]-phenyl-C61-butyric acid isopropyl ester, a hole blocking layer BCP of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, and a metal Ag electrode layer.

[0006] Further, the preparation process of the perovskite layer is as follows:

[0007] (1) Weigh CsI, MABr, FAI, PbI2 and PbBr2 according to the molar ratio of CsI:MABr:FAI:PbI2:PbBr2 = 0.05 - 0.1:0.05 - 0.1:1 - 2:1 - 2:0.05 - 0.1, dissolve them in a mixed solution of DMF and DMSO, and stir at 55 - 65 °C for 2 h to form a perovskite precursor solution with a concentration of 1.45 M;

[0008] (2) Coating the perovskite precursor solution to form a perovskite layer, thus forming the perovskite layer Cs 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3.

[0009] Further, the preparation process of the electron transport layer is as follows:

[0010] (1) Dissolve PCBM in a chlorobenzene solution and stir at 55 - 65 °C for 2 h to form a PCBM solution with a concentration of 20 mg / mL;

[0011] (2) Dissolve eC9 - 2Cl in a chlorobenzene solution and stir at 55 - 65 °C for 1 h to prepare a 10 mg / ml eC9 - 2Cl solution;

[0012] (3) Take 10 μL of the prepared eC9 - 2Cl solution, and mix the eC9 - 2Cl solution with 990 μL of the PCBM solution to form a 0.1 mg / ml eC9 - 2Cl - doped PCBM precursor solution;

[0013] (4) Coating the eC9 - 2Cl - doped PCBM precursor solution to form the electron transport layer PCBM + eC9 - 2Cl.

[0014] Another object of the present invention is to provide a preparation method of a perovskite solar cell doped with non - fullerene materials, which is characterized by including the following steps:

[0015] (1) Ultrasonically clean the ITO glass substrate with a glass cleaning solution, isopropyl alcohol solution, deionized water, and absolute ethanol for 13 - 17 min in sequence, and then clean it with an ultraviolet ozone cleaning machine for 8 - 12 min after drying;

[0016] (2) Spin - coat the hole transport layer MeO - 4PACz on the cleaned ITO glass substrate, and then anneal it at 100 - 110 °C for 8 - 12 min;

[0017] (3) Spin-coat the perovskite solution dynamically at 6000 rpm on the hole transport layer MeO-4PACz, and dynamically spin-coat 0.15 ml of chlorobenzene as an anti-solvent, and then anneal at 00-110 °C for 1 h;

[0018] (4) Spin-coat the passivation layer PEAI on the perovskite layer;

[0019] (5) Spin-coat the eC9-2Cl-doped PCBM precursor solution on the passivation layer to form the electron transport layer PCBM + eC9-2Cl;

[0020] (6) Evaporate the hole blocking layer BCP with a thickness of 5 nm on the electron transport layer in a vacuum coating machine;

[0021] (7) Evaporate the metal electrode Ag with a thickness of 120 nm on the hole blocking layer in a vacuum coating machine.

[0022] The beneficial effects of the present invention are as follows:

[0023] By introducing the non-fullerene material eC9-2Cl into the electron transport layer, the present invention improves the hydrophobicity and conductivity of the battery, enhances the stability and lifespan of the solar device, and further improves the photoelectric conversion efficiency of the perovskite solar cell;

[0024] The non-fullerene material eC9-2Cl introduced in the present invention expands the infrared absorption range of the solar cell, increases the current of the solar cell, promotes the energy level matching, passivates the uncoordinated lead iodide defects through interaction, and simultaneously improves the electron mobility;

[0025] The modification of the electron transport layer by the non-fullerene material eC9-2Cl introduced in the present invention regulates the crystallization process, improves the film morphology, forms larger and more ordered grains, inhibits ion migration, and thus inhibits the current hysteresis effect in the device. Description of the Drawings

[0026] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0027] Figure 1 It is a statistical chart of the photoelectric conversion efficiency of perovskite solar cells with and without eC9-2Cl doping;

[0028] Figure 2 It is an absorption spectrum diagram of perovskite solar cells with and without eC9-2Cl doping;

[0029] Figure 3 UPS spectra of perovskite solar cells with and without eC9-2Cl doping;

[0030] Figure 4 SCLC diagrams of perovskite thin films with and without eC9-2Cl doping;

[0031] Figure 5 SEM images of perovskite thin films with and without eC9-2Cl doping;

[0032] Figure 6 Forward and reverse scan J-V curves of perovskite solar cells with and without eC9-2Cl doping. Specific implementation manners

[0033] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without any creative work belong to the scope of protection of the present invention.

[0034] Embodiment 1

[0035] When the structure of the perovskite solar cell doped with the non-fullerene material of the present invention is as follows from bottom to top:

[0036] ITO / MeO-2PACz / Cs 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3 / PEAI / PCBM / BCP / Ag;

[0037] Its preparation method includes the following steps:

[0038] (1) Ultrasonically clean the ITO glass substrate with glass cleaning solution, isopropyl alcohol solution, deionized water and absolute ethanol in sequence for 15 min, and after drying, clean it with an ultraviolet ozone cleaner for 10 min;

[0039] (2) Spin-coat the hole transport layer MeO-4PACz on the cleaned ITO glass substrate, and then anneal it at 100 °C for 10 min;

[0040] (3) Dynamically spin-coat 1.45 M perovskite precursor solution at 6000 rpm on the hole transport layer MeO-4PACz, and dynamically spin-coat 0.15 ml of chlorobenzene as an antisolvent, and then anneal it at 100 °C for 1 h;

[0041] (4) Spin-coat the passivation layer PEAI on the perovskite layer;

[0042] (5) Spin-coat the eC9-2Cl doped PCBM precursor solution on the passivation layer to form an electron transport layer;

[0043] (6) Evaporate the hole blocking layer BCP with a thickness of 5 nm on the electron transport layer in a vacuum coating machine;

[0044] (7) Evaporate the metal electrode Ag with a thickness of 120 nm on the hole blocking layer in a vacuum coating machine.

[0045] Example 2

[0046] When the structure of the non-fullerene material doped perovskite solar cell of the present invention is as follows from bottom to top:

[0047] ITO / MeO-4PACz / Cs 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3 / PEAI / PCBM+eC9-2Cl / BCP / Ag;

[0048] Its preparation method includes the following steps:

[0049] (1) Ultrasonically clean the ITO glass substrate with glass cleaning solution, isopropyl alcohol solution, deionized water and absolute ethanol for 15 min in sequence, and then clean it with an ultraviolet ozone cleaner for 10 min after drying;

[0050] (2) Spin-coat the hole transport layer MeO-4PACz on the cleaned ITO glass substrate, and then anneal it at 100 °C for 10 min;

[0051] (3) Dynamically spin-coat the perovskite solution on the hole transport layer MeO-4PACz at 6000 rpm, and dynamically spin-coat 0.15 ml of chlorobenzene as an anti-solvent, and then anneal it at 100 °C for 1 h;

[0052] (4) Spin-coat the passivation layer PEAI on the perovskite layer;

[0053] (5) Spin-coat the eC9-2Cl doped PCBM precursor solution on the passivation layer to form an electron transport layer;

[0054] (6) Evaporate the hole blocking layer BCP with a thickness of 5 nm on the electron transport layer in a vacuum coating machine;

[0055] (7) Evaporate the metal electrode Ag with a thickness of 120 nm on the hole blocking layer in a vacuum coating machine.

[0056] Example 3

[0057] In the high-efficiency ternary perovskite solar cells with different structures prepared in Examples 1 and 2, the perovskite layer Cs 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3 is prepared as follows:

[0058] (1) Weigh CsI, MABr, FAI, PbI2 and PbBr2 in a molar ratio of CsI:MABr:FAI:PbI2:PbBr2 = 0.05 - 0.1:0.05 - 0.1:1 - 2:1 - 2:0.05 - 0.1, dissolve them in a mixed solution of DMF and DMSO, and stir at 60 °C for 2 h to form a perovskite precursor solution with a concentration of 1.45 M;

[0059] (2) Coat the perovskite precursor solution to form a perovskite layer, and then the perovskite layer Cs 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3 can be formed.

[0060] Example 4

[0061] In the high-efficiency ternary perovskite solar cells with different structures prepared in Example 2, the preparation process of the electron transport layer PCBM + eC9-2Cl is as follows:

[0062] (1) Dissolve PCBM in a chlorobenzene solution and stir at 60 °C for 2 h to form a PCBM solution with a concentration of 20 mg / mL;

[0063] (2) Dissolve eC9-2Cl in a chlorobenzene solution and stir at 60 °C for 1 h to prepare a 10 mg / ml eC9-2Cl solution;

[0064] (3) Take 10 μL of the prepared eC9-2Cl solution, and mix the eC9-2Cl solution with 990 μL of the PCBM solution to form a 0.1 mg / ml eC9-2Cl-doped PCBM precursor solution;

[0065] (4) Coat the eC9-2Cl-doped PCBM precursor solution to form the electron transport layer PCBM + eC9-2Cl.

[0066] Example 5

[0067] For the high-efficiency ternary perovskite solar cells with different structures prepared in Examples 1 and 2, their respective performance detections are as follows:

[0068] By attaching Figure 1 It can be seen that for the perovskite solar device formed by introducing eC9-2Cl, its photoelectric conversion efficiency will be significantly improved. When the introduction amount of eC9-2Cl is 0.1 mg / ml, its photoelectric conversion efficiency can be increased by more than 10%.

[0069] By attaching Figure 2 It can be seen that in the absorption spectrum, compared with the spectrum in the pure PCBM film, due to the additional infrared absorption brought by eC9-2Cl, the spectrum in the eC9-2Cl-doped mixed PCBM also broadens the infrared absorption range.

[0070] By attaching Figure 3 It can be seen that in UPS, compared with the pure PCBM film, the eC9-2Cl-doped mixed PCBM enhances the energy level matching between the electron transport layer and the perovskite layer, reducing the energy loss.

[0071] By attaching Figure 4 It can be seen that the perovskite device doped with eC9-2Cl has a higher electron mobility, and electrons are more likely to be transported through the PCBM film, reducing the accumulated carriers in the interface and lowering the defect density.

[0072] By attaching Figure 5 It can be seen that the perovskite film doped with eC9-2Cl has more ordered and plump grains, optimizing the crystallization process.

[0073] By attaching Figure 6 It can be seen that the photocurrent hysteresis phenomenon in the eC9-2Cl-doped solar cell is significantly lower than that in the undoped solar device. The significant reduction of the photocurrent hysteresis phenomenon can be attributed to the reduction of the number of defects and the emergence of chemical interactions between the perovskite and eC9-2Cl.

Claims

1. A perovskite solar cell doped with a non-fullerene material, characterized in that From bottom to top, it sequentially includes an ITO conductive glass layer, a hole transport layer of (2-(3,6-dimethyl-9H-carbazol-9-yl)butyl)phosphonic acid MeO-4PACz, a perovskite layer Cs 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3, a passivation layer of PEAI, an electron transport layer of PCBM+eC9-2Cl formed by blending a non-fullerene material eC9-2Cl and [6,6]-phenyl-C61-butyric acid isomethyl ester, a hole blocking layer of 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline BCP, and a metal Ag electrode layer.

2. The perovskite solar cell doped with a non-fullerene material according to claim 1, wherein The preparation process of the perovskite layer is as follows: (1) Weigh CsI, MABr, FAI, PbI2 and PbBr2 according to the molar ratio of CsI:MABr:FAI:PbI2:PbBr2 = 0.05 - 0.1:0.05 - 0.1:1 - 2:1 - 2:0.05 - 0.1, dissolve them in a mixed solution of DMF and DMSO, and stir at 55 - 65 °C for 2 h to form a perovskite precursor solution with a concentration of 1.45 M; (2) Coating the perovskite precursor solution to form a perovskite layer can form the perovskite layer Cs 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3.

3. The perovskite solar cell doped with a non-fullerene material according to claim 1, wherein The preparation process of the electron transport layer is as follows: (1) Dissolve PCBM in a chlorobenzene solution and stir at 55 - 65 °C for 2 h to form a PCBM solution with a concentration of 20 mg / mL; (2) Dissolve eC9-2Cl in a chlorobenzene solution and stir at 55 - 65 °C for 1 h to prepare a 10 mg / ml eC9-2Cl solution; (3) Take 10 μL of the prepared eC9-2Cl solution, and mix the eC9-2Cl solution with 990 μL of the PCBM solution to form a 0.1 mg / ml eC9-2Cl-doped PCBM precursor solution; (4) Coating the eC9-2Cl-doped PCBM precursor solution to form the electron transport layer PCBM + eC9-2Cl.

4. A method for preparing a perovskite solar cell doped with a non-fullerene material, characterized in that, It includes the following steps: (1) Ultrasonically clean the ITO glass substrate with a glass cleaning solution, isopropyl alcohol solution, deionized water and absolute ethanol for 13 - 17 min in sequence, and after drying, clean it with an ultraviolet ozone cleaner for 8 - 12 min; (2) Spin-coat the hole transport layer MeO-4PACz on the cleaned ITO glass substrate, and then anneal at 100 - 110 °C for 8 - 12 min; (3) Dynamically spin-coat the perovskite solution on the hole transport layer MeO-4PACz at 6000 rpm, and dynamically spin-coat 0.15 ml of chlorobenzene as an anti-solvent, and then anneal at 100 - 110 °C for 1 h; (4) Spin-coat the passivation layer PEAI on the perovskite layer; (5) Spin-coat the eC9-2Cl-doped PCBM precursor solution on the passivation layer to form the electron transport layer; (6) Evaporate the hole blocking layer BCP with a thickness of 5 nm on the electron transport layer in a vacuum coating machine; (7) Evaporate the metal electrode Ag with a thickness of 120 nm on the hole blocking layer in a vacuum coating machine.

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