Perovskite thin film solar cell and method of manufacturing the same

Abstract

The application discloses a perovskite thin film solar cell and a preparation method thereof. The perovskite thin film solar cell comprises a cathode, an electron transport layer, a perovskite active layer, a hole transport layer and an anode which are sequentially arranged along a set direction. A dense barrier layer is arranged between the electron transport layer and the perovskite active layer, and the dense barrier layer is used for at least inhibiting ion migration between the cathode and / or the electron transport layer and the perovskite active layer. The application can effectively inhibit the attenuation of device efficiency by arranging the dense barrier layer in the structure of the perovskite thin film solar cell, significantly improves the stability of the perovskite solar cell, and the process of the application is simple, low in cost and easy to be applied in large scale.

Description

Technical Field

[0001] This invention relates to a perovskite thin-film solar cell, and more particularly to a perovskite thin-film solar cell and its preparation method, belonging to the field of optoelectronic functional materials and devices technology. Background Technology

[0002] Organic-inorganic perovskite materials have become strong candidates in the photovoltaic field due to their excellent photoelectric properties. Since the first report of a perovskite solar cell with a photoelectric conversion efficiency of 3.8% in 2009, researchers have made rapid progress over the past decade, achieving a conversion efficiency of 25%. To date, many perovskite solar cell structures have been developed, including mesoporous structures, nip (upright) planar heterostructures, and pin (inverted) planar heterostructures. Among these structures, the inverted planar heterostructure offers advantages such as low-temperature fabrication, low hysteresis, and good low-temperature performance, and shows great promise for space applications, thus being widely used in laboratory research.

[0003] The inverted planar heterostructure device comprises a transparent conductive electrode, a hole transport layer and a perovskite active layer, an electron transport layer, and an uppermost metal electrode. This device has a simple structure, can be fabricated using a solution-based method at temperatures below 130°C, and shows potential application prospects for large-area printing processes using this method. Furthermore, its efficiency reaches 23%, demonstrating potential commercial value.

[0004] Currently, a significant factor hindering the commercialization of perovskite devices is their stability. Related research has revealed that during operation, mobile ions within the perovskite device migrate, leading to a loss of photoelectric conversion performance.

[0005] The perovskite active layer is the most critical component of a perovskite solar cell device. However, during experiments, it was discovered that under the induction of light and heat, organic cations and halide anions in the perovskite active layer migrate and pass through the entire electron transport layer to reach the metal electrode, causing a decrease in the electrical performance of the electron transport layer and damage to the metal electrode. Furthermore, metal ions also migrate into the perovskite layer, causing damage to the perovskite active layer and resulting in a severe degradation of device performance. Summary of the Invention

[0006] The main objective of this invention is to provide a perovskite thin-film solar cell and its preparation method, so as to overcome the shortcomings of the prior art.

[0007] To achieve the aforementioned objectives, the technical solution adopted by this invention includes:

[0008] This invention provides a perovskite thin-film solar cell, comprising a cathode, an electron transport layer, a perovskite active layer, a hole transport layer, and an anode arranged sequentially along a predetermined direction. A dense barrier layer is further provided between the electron transport layer and the perovskite active layer, and the dense barrier layer is used to suppress ion migration between the cathode and / or the electron transport layer and the perovskite active layer.

[0009] This invention also provides a method for fabricating the perovskite thin-film solar cell, including the steps of fabricating a cathode, an electron transport layer, a perovskite active layer, a hole transport layer, and an anode. The method further includes forming a dense barrier layer on the perovskite active layer, and then forming an electron transport layer on the dense barrier layer.

[0010] Compared with the prior art, the advantages of the present invention include:

[0011] (1) The present invention provides a dense barrier layer between the perovskite active layer and the electron transport layer interface. The ion barrier layer can suppress the migration of ions in the perovskite active layer into the electron transport layer, thereby suppressing the device performance degradation caused by the decrease in the electrical properties of the electron transport layer material due to the ion migration behavior, thereby improving the stability of the device.

[0012] (2) The present invention provides a dense barrier layer between the perovskite active layer and the electron transport layer. The ion barrier layer can suppress the migration of ions in the perovskite active layer to the cathode, thereby suppressing the damage to the cathode caused by the ion migration behavior and improving the stability performance of the device.

[0013] (3) The present invention provides a dense barrier layer between the interface of the perovskite active layer and the electron transport layer. The ion barrier layer can suppress the migration of metal ions in the cathode into the perovskite active layer, thereby suppressing the damage to the perovskite active layer caused by the migration of these ions and thus improving the stability performance of the device.

[0014] (4) The present invention provides a dense barrier layer between the interface of the perovskite active layer and the electron transport layer. The ion barrier layer can prevent external water and oxygen from penetrating into the perovskite active layer and thus protect the perovskite active layer, thereby improving the stability performance of the device.

[0015] (5) The raw material for preparing the ion blocking layer in this invention is organosilane, which is widely available and inexpensive. Furthermore, after the organosilane is deposited on the perovskite active layer by printing, coating, or dissolving the organosilane in an antisolvent during the preparation of the perovskite active layer, the ion blocking layer can be prepared by simple short-term VUV irradiation, which ensures the low-temperature, solution-compatible preparation of the entire device and is suitable for the preparation of large-area flexible perovskite solar energy devices. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of a perovskite solar thin-film battery in a typical embodiment of the present invention;

[0017] Figure 2 This is the contact angle of the perovskite thin film prepared in Example 1 of the present invention, and the test solution is water;

[0018] Figure 3 This is the JV curve of the perovskite solar thin-film battery prepared in Example 1 of this invention;

[0019] Figures 4a-4d This is a graph showing the performance of the perovskite solar thin-film battery prepared in Example 1 of this invention as a function of time during the degradation test;

[0020] Figure 5 The contact angle of the perovskite / dense barrier layer film prepared in Example 2 of the present invention is measured in water.

[0021] Figure 6 The XPS binding energy peak of Si(2p) in the perovskite / dense barrier layer film prepared in Example 2 of this invention;

[0022] Figure 7 This is the JV curve of the perovskite solar thin-film battery prepared in Example 2 of this invention;

[0023] Figures 8a-8d This is a graph showing the performance of the perovskite solar thin-film battery prepared in Example 2 of the present invention over time during the degradation test;

[0024] Figure 9 The contact angle of the perovskite / dense barrier layer film prepared in Example 2 of the present invention is measured in water.

[0025] Figure 10 The XPS binding energy peak of Si(2p) in the perovskite / dense barrier layer film prepared in Example 3 of this invention;

[0026] Figure 11 This is the JV curve of the perovskite solar thin-film battery prepared in Example 3 of this invention;

[0027] Figures 12a-12d This is a graph showing the performance of the perovskite solar thin-film battery prepared in Example 3 of the present invention over time during the degradation test;

[0028] Figure 13 The contact angle of the perovskite / dense barrier layer film prepared in Example 4 of this invention is measured in water as the test solution.

[0029] Figure 14The XPS binding energy peak of Si(2p) in the perovskite / dense barrier layer film prepared in Example 4 of this invention;

[0030] Figure 15 This is the JV curve of the perovskite solar thin-film battery prepared in Example 4 of this invention;

[0031] Figures 16a-16d This is a graph showing the performance of the perovskite solar thin-film battery prepared in Example 4 of this invention as a function of time during the degradation test.

[0032] Figure 17 The contact angle of the perovskite / dense barrier layer film prepared in Example 5 of the present invention is measured in water.

[0033] Figure 18 The XPS binding energy peak of Si(2p) in the perovskite / dense barrier layer film prepared in Example 5 of this invention;

[0034] Figure 19 This is the JV curve of the perovskite solar thin-film battery prepared in Example 5 of this invention;

[0035] Figures 20a-20d This is a graph showing the performance of the perovskite solar thin-film battery prepared in Example 5 of the present invention over time during a degradation test;

[0036] Figure 21 The contact angle of the perovskite / dense barrier layer film prepared in Example 6 of the present invention is measured in water solution.

[0037] Figure 22 The XPS binding energy peak of Si(2p) in the perovskite / dense barrier layer film prepared in Example 6 of this invention;

[0038] Figure 23 This is the JV curve of the perovskite solar thin-film battery prepared in Example 6 of this invention;

[0039] Figure 24 This is the JV curve of the perovskite solar thin-film battery prepared in Example 7 of this invention. Detailed Implementation

[0040] In view of the shortcomings of the prior art, the inventors of this invention, through long-term research and extensive practice, have proposed the technical solution of this invention. The following will further explain and illustrate this technical solution, its implementation process, and its principles.

[0041] This invention provides a perovskite thin-film solar cell, comprising a cathode, an electron transport layer, a perovskite active layer, a hole transport layer, and an anode arranged sequentially along a predetermined direction. A dense barrier layer is further provided between the electron transport layer and the perovskite active layer, and the dense barrier layer is used to suppress ion migration between the cathode and / or the electron transport layer and the perovskite active layer.

[0042] In one specific embodiment, the dense barrier layer is a non-metallic oxide layer formed by photochemical conversion.

[0043] In one specific embodiment, the material of the non-metallic oxide layer includes silicon oxide.

[0044] In one specific embodiment, the thickness of the dense barrier layer is 1-30 nm, preferably 2-10 nm.

[0045] In one specific embodiment, the dense barrier layer is also used to block water vapor and oxygen.

[0046] In one specific embodiment, the dense barrier layer is a silicon oxide layer formed by the conversion of organosilanes under vacuum ultraviolet conditions. The organosilanes include siloxanes and / or silazanes, but are not limited thereto. For example, the siloxanes include polydimethylsiloxanes, and the silazanes include perhydropolysilazanes, etc.

[0047] In one specific embodiment, the electron transport layer is made of polymers and / or oxides; for example, the polymer may be PC. 61 BM, etc., the oxide can be ZnO, etc., but is not limited thereto.

[0048] In one specific embodiment, the thickness of the electron transport layer is 30-60 nm.

[0049] In one specific embodiment, the cathode can be a metal electrode such as gold, silver, or aluminum. The cathode can be prepared by vacuum thermal evaporation. For ease of testing, the cathode can be in various forms, such as strip-shaped or dot-shaped.

[0050] In one specific embodiment, the thickness of the cathode is 80-100 nm.

[0051] In one specific embodiment, the material of the perovskite active layer can be ABX3, wherein A can be an organic cation or an inorganic cation, such as organic cations such as methylamine or methyl ether, or inorganic cations such as Cs; B can be any one or a combination of two or more cations such as Pb ions, Sn ions, and Ge ions; and X can be a halide ion, such as Cl ions, Br ions, I ions, etc.

[0052] In one specific embodiment, the thickness of the perovskite active layer is 200-500 nm.

[0053] In one specific embodiment, the hole transport layer is made of organic or inorganic semiconductor materials. For example, the organic semiconductor material may be any one or a combination of two or more of P3CT-Na, 3,4-ethylenedioxythiophene polymer-polystyrene sulfonate, and CPE-K, but is not limited thereto.

[0054] In one specific embodiment, the anode is made of a transparent conductive material. For example, the transparent conductive material may be any one or a combination of two or more of indium tin oxide, fluorine-doped tin oxide, and Ag mesh transparent conductive film, but is not limited thereto.

[0055] In one specific embodiment, the anode is disposed on a transparent substrate, the transparent substrate being made of glass or PET, but not limited thereto.

[0056] This invention also provides a method for fabricating the perovskite thin-film solar cell, including the steps of fabricating a cathode, an electron transport layer, a perovskite active layer, a hole transport layer, and an anode. The method further includes forming a dense barrier layer on the perovskite active layer, and then forming an electron transport layer on the dense barrier layer.

[0057] In one specific embodiment, the preparation method includes: covering the perovskite active layer with a continuous organosilane layer, and then irradiating the organosilane layer with vacuum ultraviolet light to form the dense barrier layer.

[0058] In one specific embodiment, the preparation method specifically includes:

[0059] The organosilane solution is coated onto the perovskite active layer to form the organosilane layer, and the organosilane layer is irradiated with vacuum ultraviolet light to form the dense barrier layer.

[0060] Alternatively, in the process of fabricating the perovskite active layer using the anti-solvent method, an organosilane solution is applied to the perovskite precursor film used to form the perovskite active layer, followed by annealing to complete the fabrication of the perovskite active layer, and an organosilane film is formed on the perovskite active layer. Subsequently, the organosilane layer is subjected to vacuum ultraviolet light irradiation to form the dense barrier layer.

[0061] In one specific embodiment, the organosilane includes siloxanes and / or silazanes.

[0062] In one specific embodiment, the volume ratio of solute to solvent in the organosilane solution is 0-4%.

[0063] In one specific embodiment, the wavelength of the ultraviolet light used in the vacuum ultraviolet irradiation is 150-200nm, preferably 172nm.

[0064] In one specific embodiment, the vacuum ultraviolet irradiation time is within 30 minutes, and the irradiation method can be direct irradiation by a light source.

[0065] In one specific embodiment, the vacuum ultraviolet irradiation is performed under a nitrogen atmosphere.

[0066] The following will further explain the technical solution, its implementation process and principle with reference to the accompanying drawings. Unless otherwise specified, the deposition, coating, printing and other processes used in the embodiments of the present invention are known to those skilled in the art.

[0067] Please see Figure 1 A schematic diagram of the structure of a perovskite thin-film solar cell (hereinafter referred to as "perovskite device"), which may include a cathode 1, an electron transport layer 2, a dense barrier layer 3, a perovskite light-absorbing layer 4 (also known as "perovskite active layer"), a hole transport layer 5, an anode 6 and a transparent substrate 7 arranged sequentially along a set direction.

[0068] Compared to conventional inverted planar heterojunction perovskite solar cells, the dense barrier layer in this invention is located between the electron transport layer and the perovskite active layer interface. This dense barrier layer can suppress the migration of ions in the perovskite active layer towards the electron transport layer / cathode and the migration of metal ions in the cathode into the perovskite active layer. Furthermore, the dense barrier layer can prevent external water and oxygen from penetrating into the perovskite active layer, thereby protecting the stability of the device.

[0069] In a typical embodiment of the present invention, a method for preparing a perovskite thin-film solar cell includes the following steps:

[0070] (1) A hole transport layer 5 is prepared on the surface of anode 6;

[0071] (2) A perovskite active layer 4 is prepared on the surface of the hole transport layer 5 described above;

[0072] (3) A dense barrier layer 3 is prepared on the surface of the perovskite active layer 4;

[0073] (4) An electron transport layer 2 is prepared on the surface of the above-mentioned dense barrier layer 3;

[0074] (5) Prepare one or more metal layers as cathode 1 on the surface of the electron transport layer 2;

[0075] The dense barrier layer 3 can be formed by applying an organosilane solution to the perovskite active layer by printing or coating, or by dissolving the organosilane in an antisolvent during the preparation of the perovskite active layer, and then irradiating it with vacuum ultraviolet light. The printing method includes, but is not limited to, gravure printing, screen printing, or inkjet printing, and the coating method includes, but is not limited to, slot coating, spin coating, etc.

[0076] As one preferred method, the preparation method specifically includes: dissolving the organosilane material in an antisolvent (such as chlorobenzene) required for preparing the perovskite active layer; and depositing the organosilane solution onto the perovskite active layer while preparing the perovskite active layer.

[0077] The technical solution of the present invention will be further described below with reference to some typical implementation examples, but the present invention is not limited to the following embodiments. The single specific material selected in the embodiments does not limit the selection of other materials, but is only used as an example to illustrate the technical solution of the invention.

[0078] Example 1

[0079] A method for fabricating a perovskite thin-film solar cell (hereinafter referred to as a device) includes the following steps:

[0080] 1) Clean the customized patterned ITO transparent conductive glass substrate with detergent, deionized water, acetone (twice), and isopropanol (twice) for 30 minutes each. Then, use nitrogen to dry the cleaned ITO transparent conductive glass substrate and then treat it with an ultraviolet (UV) cleaning machine for 30 minutes.

[0081] 2) Spin-coat PEDOT:PSS solution onto the cleaned ITO transparent conductive glass substrate at a speed of 3500 rpm for 45 s, and then anneal in air at 130°C for 10 min to form a hole transport layer.

[0082] 3) Preparation of perovskite thin films (i.e., perovskite active layers, hereinafter the same) on hole transport layers using an anti-solvent method: Perovskite precursors (e.g., CH3NH3PbI3 solution) were deposited on the hole transport layers by spin coating. Specifically, spin coating was performed continuously at 1000 rpm for 10 s and then at 4000 rpm for 30 s. During spin coating, chlorobenzene (400 μL) was rapidly dropped onto the perovskite thin film 27 s after the start of spin coating. The film was then annealed on a hot plate at 100 °C for 10 min. The resulting perovskite thin film had a water contact angle as shown in the figure. Figure 2 As shown, the results indicate that the water contact angle of the perovskite film is 26°, indicating that the perovskite film is hydrophilic.

[0083] 4) Spin-coating PC onto the perovskite film 61 PC was obtained from BM solution (chloroform solvent, 20 mg / mL) 61 BM electron transport layer, spin-coated at 1000 rpm for 60 s;

[0084] 5) In the vapor deposition chamber, at 1×10 -5 At a pressure of Pa, PC 61 A 100nm Al electrode is deposited on the BM electron transport layer to obtain a perovskite thin-film solar cell.

[0085] The performance of the obtained perovskite thin-film solar cell was tested, and the JV curve of the obtained perovskite thin-film solar cell is shown below. Figure 3 As shown in Table 1, the detailed performance parameters of the perovskite thin-film solar cell obtained in this embodiment are shown. Simultaneously, the stability of the obtained perovskite thin-film solar cell was tested under a +1V bias voltage, and the test results are as follows: Figures 4a-4d As shown; in this embodiment, the average photoelectric conversion efficiency of the perovskite thin-film solar cell is 13.36%, and the perovskite thin-film solar cell completely fails after aging for 400 hours.

[0086] Table 1 Performance parameters of devices without dense barrier layer

[0087] Voc(V) <![CDATA[Jsc(mA / cm 2 )]]> FF PCE (%) 1.01±0.03 17.82±0.18 0.75±0.02 13.68±0.35

[0088] Example 2:

[0089] A method for fabricating a perovskite thin-film solar cell includes the following steps:

[0090] 1) Mix the polymer of polydimethylsiloxane (PDMS) (poly(dimethylmethylvinylsiloxane)) and the crosslinking agent (poly(dimethylmethylhydrosiloxane)) at a mass ratio of 5:1 and stir for 30 minutes to mix evenly. Then, use a vacuum drying oven to create vacuum conditions to remove the air bubbles generated during the stirring of PDMS. After that, dilute PDMS with chlorobenzene to a concentration of 0.1% for later use.

[0091] 2) Clean the customized patterned ITO transparent conductive glass substrate with detergent, deionized water, acetone (twice), and isopropanol (twice) for 30 minutes each. Then, dry the cleaned ITO transparent conductive glass substrate with nitrogen and then treat it with an ultraviolet (UV) cleaning machine for 30 minutes.

[0092] 3) PEDOT:PSS solution was spin-coated at 3500 rpm for 45 s on the cleaned ITO transparent conductive glass substrate, and then annealed in air at 130°C for 10 min to form a hole transport layer.

[0093] 4) Perovskite thin films are prepared on the hole transport layer using the anti-solvent method:

[0094] The perovskite precursor (e.g., CH3NH3PbI3 solution) was deposited on the hole transport layer using a spin-coating method. Specifically, the spin-coating was performed continuously at a speed of 1000 rpm for 10 s and at a speed of 4000 rpm for 30 s. During the spin-coating process, 27 s from the start of the spin-coating, a 400 μL solution of chlorobenzene-diluted PDMS was rapidly dropped onto the perovskite film. The film was then annealed on a hot plate at 100 °C for 10 min to form a perovskite / PDMS film. At this time, the deposition of the PDMS film on the perovskite film was also completed simultaneously during the preparation of the perovskite film.

[0095] The water contact angle of the prepared perovskite / PDMS thin film is as follows: Figure 5 As shown, the results indicate that the water contact angle of the perovskite / PDMS film is 45°, indicating an increase in the hydrophobicity of the PDMS film. This is further supported by the X-ray photoelectron spectroscopy (XPS) spectrum of the perovskite / PDMS film. Figure 6 It can be seen that the XPS binding energy peak of Si(2p) in the perovskite / PDMS film is 102.4 eV, which is the typical peak position of Si in PDMS.

[0096] 5) Subsequently, PC is spin-coated onto the PDMS film. 61 PC was obtained from BM solution (chloroform solvent, 20 mg / mL) 61 BM electron transport layer, spin-coated at 1000 rpm for 60 s;

[0097] 6) In the vapor deposition chamber, at 1×10 -5 At a pressure of Pa, PC 61 A 100nm Al electrode is deposited on the BM electron transport layer to obtain a perovskite thin-film solar cell.

[0098] The performance of the obtained perovskite thin-film solar cell was tested, and the JV curve of the obtained perovskite thin-film solar cell is shown below. Figure 7 As shown in Table 2, detailed performance parameters of the device can be found therein. Simultaneously, stability tests were conducted on the obtained perovskite thin-film solar cells under a +1V bias voltage, and the test results are as follows: Figures 8a-8d As shown, the average photoelectric conversion efficiency of the perovskite thin-film solar cell in this embodiment is 12.38%, and the perovskite thin-film solar cell completely fails after aging for 400 hours.

[0099] In this embodiment, depositing PDMS on the perovskite thin film did not improve the stability of the perovskite thin-film solar cell. This is because the amount of PDMS deposited on the perovskite thin film is very small and still in a gel-like state. This is because the amount of PDMS deposited on the perovskite thin film is small, and it is still in a gel-like state when spin-coated with PC... 61 PC during BM 61 BM dissolves in the PCBM solution, thus preventing the formation of a dense barrier layer.

[0100] Table 2 Performance parameters of devices without VUV illumination

[0101] Voc(V) <![CDATA[Jsc(mA / cm 2 )]]> FF PCE (%) 0.99±0.02 17.42±0.41 0.72±0.01 12.38±0.56

[0102] Example 3:

[0103] A method for fabricating a perovskite thin-film solar cell includes the following steps:

[0104] 1) Mix the polymer of polydimethylsiloxane (PDMS) (poly(dimethylmethylvinylsiloxane)) and the crosslinking agent (poly(dimethylmethylhydrosiloxane)) at a mass ratio of 5:1 and stir for 30 minutes to mix evenly. Then, use a vacuum drying oven to create vacuum conditions to remove the air bubbles generated during the stirring of PDMS. After that, dilute PDMS with chlorobenzene to a concentration of 0.1% for later use.

[0105] 2) Clean the customized patterned ITO transparent conductive glass substrate with detergent, deionized water, acetone (twice), and isopropanol (twice) for 30 minutes each. Then, use nitrogen to dry the cleaned ITO transparent conductive glass substrate and then treat it with an ultraviolet (UV) cleaning machine for 30 minutes.

[0106] 3) PEDOT:PSS solution was spin-coated at 3500 rpm for 45 s on the cleaned ITO transparent conductive glass substrate, and then annealed in air at 130°C for 10 min to form a hole transport layer.

[0107] 4) Preparation of perovskite thin films using the anti-solvent method: Perovskite precursor (e.g., CH3NH3PbI3 solution) was continuously spin-coated at 1000 rpm for 10 s and at 4000 rpm for 30 s; and during the spin-coating process, 27 s from the start of spin-coating, the above-mentioned chlorobenzene diluted PDMS solution (400 μL) was rapidly dropped onto the perovskite thin film, and then annealed on a hot stage at 100 °C for 10 min to form a perovskite / PDMS thin film. At this time, PDMS deposition on the perovskite thin film was also completed during the preparation of the perovskite thin film. Afterwards, the PDMS thin film was irradiated with a 172 nm ultraviolet lamp for 10 s, and the distance between the PDMS thin film and the ultraviolet lamp source was 5 mm.

[0108] The contact angle of the aqueous solution of the perovskite / PDMS thin film prepared by the above process is as follows: Figure 9 Its contact angle is 42°, indicating an increase in the hydrophobicity of the PDMS film. The X-ray photoelectron spectroscopy (XPS) spectrum of the perovskite / PDMS film is shown below. Figure 10 It can be seen that the XPS binding energy peak of Si(2p) in the perovskite / PDMS film is still 102.4 eV, which is consistent with the film before UV irradiation. However, the PDMS film can no longer be dissolved by the PDMS solution at this time. In summary, it shows that the PDMS film was cured after 10s of VUV irradiation.

[0109] 5) Spin-coating PC onto PDMS film 61 PC was obtained from BM solution (chloroform solvent, 20 mg / mL) 61 BM electron transport layer, spin-coated at 1000 rpm for 60 s;

[0110] 6) In the vapor deposition chamber, at 1×10 -5 At a pressure of Pa, the PC 61 A 100nm Al electrode is deposited on the BM electron transport layer to obtain a perovskite thin-film solar cell.

[0111] The performance of the obtained perovskite thin-film solar cells was tested, and the JV curve of the final device is shown below. Figure 11 As shown in Table 3, detailed performance parameters of the perovskite thin-film solar cell in this embodiment can be found therein. Stability tests were also conducted on the obtained perovskite thin-film solar cell under a +1V bias voltage, and the test results are as follows. Figures 12a-12d As shown, the average photoelectric conversion efficiency of the perovskite thin-film solar cell in this embodiment is 12.27%, and the photoelectric conversion efficiency of the perovskite thin-film solar cell remains at 43% of the initial photoelectric conversion efficiency after aging for 550 hours.

[0112] Table 3 Performance parameters of VUV-illuminated PDMS 10s devices

[0113] Voc(V) <![CDATA[Jsc(mA / cm 2 )]]> FF PCE (%) 1.01±0.02 16.24±0.39 0.75±0.02 12.27±0.20

[0114] Example 4:

[0115] A method for fabricating a perovskite thin-film solar cell includes the following steps:

[0116] 1) Mix the polymer of polydimethylsiloxane (PDMS) (poly(dimethylmethylvinylsiloxane)) and the crosslinking agent (poly(dimethylmethylhydrosiloxane)) at a mass ratio of 5:1 and stir for 30 minutes to mix evenly. Then, use a vacuum drying oven to create vacuum conditions to remove the air bubbles generated during the stirring of PDMS. After that, dilute PDMS with chlorobenzene to a concentration of 0.1% for later use.

[0117] 2) Clean the customized patterned ITO transparent conductive glass substrate with detergent, deionized water, acetone (twice), and isopropanol (twice) for 30 minutes each. Then, use nitrogen to dry the cleaned ITO transparent conductive glass substrate and then treat it with an ultraviolet (UV) cleaning machine for 30 minutes.

[0118] 3) PEDOT:PSS solution was spin-coated at 3500 rpm for 45 s on the cleaned ITO transparent conductive glass substrate, and then annealed in air at 130°C for 10 min to form a hole transport layer.

[0119] 4) The perovskite thin film was prepared using the anti-solvent method:

[0120] The perovskite precursor (CH3NH3PbI3 solution) was continuously spin-coated at 1000 rpm for 10 s and then at 4000 rpm for 30 s. During the spin-coating process, 27 s from the start of spin-coating, 400 μL of the chlorobenzene-diluted PDMS solution was rapidly dropped onto the perovskite film. The film was then annealed on a hot plate at 100 °C for 10 min to form a perovskite / PDMS film. At this time, the deposition of the PDMS film on the perovskite film was also completed simultaneously during the preparation of the perovskite film. Afterward, the PDMS film was irradiated under a 172 nm UV lamp for 30 s, with a distance of 5 mm between the PDMS film and the UV lamp.

[0121] The contact angle of the aqueous solution of the perovskite / PDMS thin film prepared by the above process is as follows: Figure 13 Its contact angle is 45°, indicating an increase in the hydrophobicity of the PDMS film. The X-ray photoelectron spectroscopy (XPS) spectrum of the perovskite / PDMS film is shown below. Figure 14 It can be seen that the XPS binding energy peak of Si(2p) in the perovskite / PDMS film is still 102.4 eV, which is consistent with the PDMS film before irradiation. However, the PDMS film can no longer be dissolved by the PDMS solution at this time. In summary, it shows that the PDMS film was cured after irradiation with VUV light for 30s.

[0122] 5) Subsequently, PC is spin-coated onto the PDMS film. 61 PC was obtained from BM solution (chloroform solvent, 20 mg / mL) 61BM electron transport layer, spin-coated at 1000 rpm for 60 s;

[0123] 6) In the vapor deposition chamber, at 1×10 -5 At a pressure of Pa, PC 61 A 100nm Al electrode is deposited on the BM electron transport layer to obtain a perovskite thin-film solar cell.

[0124] The performance of the obtained perovskite thin-film solar cells was tested, and the JV curve of the final device is shown below. Figure 15 As shown in Table 4, detailed performance parameters of the perovskite thin-film solar cell in this embodiment can be found therein. Simultaneously, stability tests were performed on the obtained perovskite thin-film solar cell under a +1V bias voltage, and the test results are as follows. Figures 16a-16d As shown. The average photoelectric conversion efficiency of the perovskite thin-film solar cell in this embodiment is 10.27%. After aging for 550 hours, the photoelectric conversion efficiency of the perovskite thin-film solar cell still remains at 43% of the initial photoelectric conversion efficiency.

[0125] Table 4 Performance parameters of VUV-illuminated PDMS 30s devices

[0126]

[0127]

[0128] Example 5:

[0129] A method for fabricating a perovskite thin-film solar cell includes the following steps:

[0130] 1) Mix the polymer of polydimethylsiloxane (PDMS) (poly(dimethylmethylvinylsiloxane)) and the crosslinking agent (poly(dimethylmethylhydrosiloxane)) at a mass ratio of 5:1 and stir for 30 minutes to mix evenly. Then, use a vacuum drying oven to create vacuum conditions to remove the air bubbles generated during the stirring of PDMS. After that, dilute PDMS with chlorobenzene to a concentration of 0.1% for later use.

[0131] 2) Clean the customized patterned ITO transparent conductive glass substrate with detergent, deionized water, acetone (twice), and isopropanol (twice) for 30 minutes each. Then, dry the cleaned ITO transparent conductive glass substrate with nitrogen and then treat it with an ultraviolet (UV) cleaner for 30 minutes.

[0132] 3) PEDOT:PSS solution was spin-coated at 3500 rpm for 45 s on the cleaned ITO transparent conductive glass substrate, and then annealed in air at 130°C for 10 min to form a hole transport layer.

[0133] 4) The perovskite thin film was prepared using the anti-solvent method:

[0134] The perovskite precursor (CH3NH3PbI3 solution) was continuously spin-coated at 1000 rpm for 10 s and at 4000 rpm for 30 s. During the spin-coating process, 27 s from the start of spin-coating, 400 μL of the chlorobenzene-diluted PDMS solution was rapidly dropped onto the perovskite film. The film was then annealed on a hot stage at 100 °C for 10 min to form a perovskite / PDMS film. At this time, PDMS deposition on the perovskite film was also completed during the perovskite film preparation process. The PDMS film was then irradiated under a 172 nm UV lamp for 3 min, with a distance of 5 mm between the PDMS film and the UV lamp source.

[0135] The contact angle of the aqueous solution of the perovskite / PDMS thin film prepared by the above process is as follows: Figure 17 Its contact angle is 35°, and the X-ray photoelectron spectroscopy (XPS) spectrum of the perovskite / PDMS thin film is shown. Figure 18 It can be seen that the XPS binding energy peak of Si(2p) in the perovskite / PDMS film is 102.8 eV, and its peak position has shifted compared to the Si peak position in PDMS. The change in the binding contact angle indicates that the PDMS film has partially bonded to SiO. x The conversion;

[0136] 5) Spin-coating PC onto PDMS film 61 PC was obtained from BM solution (chloroform solvent, 20 mg / mL) 61 BM electron transport layer, spin-coated at 1000 rpm for 60 s;

[0137] 6) In the vapor deposition chamber, at 1×10 -5 At a pressure of Pa, PC 61 A 100nm Al electrode is deposited on the BM electron transport layer to obtain a perovskite thin-film solar cell.

[0138] The performance of the obtained perovskite thin-film solar cells was tested, and the JV curve of the final device is shown below. Figure 19 As shown in Table 5, detailed performance parameters of the perovskite thin-film solar cell are available in Table 5. Stability tests were also conducted on the obtained perovskite thin-film solar cell under a +1V bias voltage, and the test results are as follows. Figures 20a-20d As shown. The average photoelectric conversion efficiency of the perovskite thin-film solar cell in this embodiment is 7.67%. After aging for 550 hours, the photoelectric conversion efficiency of the perovskite thin-film solar cell still remains at 66% of the initial photoelectric conversion efficiency.

[0139] Table 5 Performance parameters of PDMS devices under VUV illumination for 3 minutes

[0140] Voc(V) <![CDATA[Jsc(mA / cm 2 )]]> FF PCE (%) 0.96±0.03 11.02±0.61 0.73±0.07 7.67±0.83

[0141] Example 6:

[0142] A method for fabricating a perovskite thin-film solar cell includes the following steps:

[0143] 1) Mix the polymer of polydimethylsiloxane (PDMS) (poly(dimethylmethylvinylsiloxane)) and the crosslinking agent (poly(dimethylmethylhydrosiloxane)) at a mass ratio of 5:1 and stir for 30 minutes to mix evenly. Then, use a vacuum drying oven to create vacuum conditions to remove the air bubbles generated during the stirring of PDMS. After that, dilute PDMS with chlorobenzene to a concentration of 0.1% for later use.

[0144] 2) The customized patterned ITO transparent conductive glass substrate was ultrasonically cleaned for 30 minutes each using dish soap, deionized water, acetone (twice), and isopropanol (twice). Then, the cleaned ITO transparent conductive glass substrate was dried with nitrogen gas and then treated with an ultraviolet (UV) cleaner for 30 minutes.

[0145] 3) PEDOT:PSS solution was spin-coated at 3500 rpm for 45 s on the cleaned ITO transparent conductive glass substrate, and then annealed in air at 130°C for 10 min to form a hole transport layer.

[0146] 4) The perovskite thin film was prepared using the anti-solvent method:

[0147] The perovskite precursor (CH3NH3PbI3 solution) was continuously spin-coated at 1000 rpm for 10 s and at 4000 rpm for 30 s. During the spin-coating process, 27 s from the start of spin-coating, the above-mentioned chlorobenzene diluted PDMS solution (400 μL) was rapidly dropped onto the perovskite film. Then, it was annealed on a hot stage at 100 °C for 10 min to form a perovskite / PDMS film. At this time, the deposition of PDMS on the perovskite film was also completed during the preparation of the perovskite film. After that, the PDMS film was irradiated under a 172 nm UV lamp for 10 min, with the distance between the PDMS film and the UV lamp source being 5 mm.

[0148] The contact angle of the aqueous solution of the perovskite / PDMS thin film prepared by the above process is as follows: Figure 21 Its contact angle is 22°, and the X-ray photoelectron spectroscopy (XPS) spectrum of the perovskite / PDMS thin film is shown. Figure 22It can be seen that the XPS binding energy peak of Si(2p) in the perovskite / PDMS film is 103.2 eV, which is the typical 2p binding energy peak of Si in SiO2. The change in the binding contact angle indicates that the PDMS film has undergone bonding to SiO2. x The conversion;

[0149] 5) Spin-coating PC onto PDMS film 61 PC was obtained from BM solution (chloroform solvent, 20 mg / mL) 61 BM electron transport layer, spin-coated at 1000 rpm for 60 s;

[0150] 6) In the vapor deposition chamber, at 1×10 -5 At a pressure of Pa, PC 61 A 100nm Al electrode is deposited on the BM electron transport layer to obtain a perovskite thin-film solar cell.

[0151] The performance of the obtained perovskite thin-film solar cells was tested, and the JV curve of the final device is shown below. Figure 23 As shown, detailed performance parameters of the perovskite thin-film solar cell can be found in Table 6. The average photoelectric conversion efficiency of the perovskite thin-film solar cell in this embodiment is 4.20%.

[0152] Table 6 Performance parameters of PDMS devices under VUV illumination for 10 min

[0153] Voc(V) <![CDATA[Jsc(mA / cm 2 )]]> FF PCE (%) 1.02±0.01 8.88±0.43 0.46±0.05 4.20±0.44

[0154] Example 7:

[0155] A method for fabricating a perovskite thin-film solar cell includes the following steps:

[0156] 1) Mix the polymer of polydimethylsiloxane (PDMS) (poly(dimethylmethylvinylsiloxane)) and the crosslinking agent (poly(dimethylmethylhydrosiloxane)) at a mass ratio of 5:1 and stir for 30 minutes to mix evenly. Then, use a vacuum drying oven to create vacuum conditions to remove the air bubbles generated during the stirring of PDMS. After that, dilute PDMS with chlorobenzene to a concentration of 0.1% for later use.

[0157] 2) The customized patterned ITO transparent conductive glass substrate was ultrasonically cleaned for 30 minutes each using dish soap, deionized water, acetone (twice), and isopropanol (twice). Then, the cleaned ITO transparent conductive glass substrate was dried with nitrogen gas and then treated with an ultraviolet (UV) cleaner for 30 minutes.

[0158] 3) PEDOT:PSS solution was spin-coated at 3500 rpm for 45 s on the cleaned ITO transparent conductive glass substrate, and then annealed in air at 130°C for 10 min to form a hole transport layer.

[0159] 4) The perovskite thin film was prepared using the anti-solvent method:

[0160] The perovskite precursor (CH3NH3PbI3 solution) was continuously spin-coated at 1000 rpm for 10 s and at 4000 rpm for 30 s. During the spin-coating process, 27 s from the start of spin-coating, the above-mentioned chlorobenzene diluted PDMS solution (400 μL) was rapidly dropped onto the perovskite film. Then, it was annealed on a hot stage at 100 °C for 10 min to form a perovskite / PDMS film. At this time, the deposition of PDMS on the perovskite film was also completed during the preparation of the perovskite film. After that, the PDMS film was irradiated under a 172 nm UV lamp for 30 min, with the distance between the PDMS film and the UV lamp source being 5 mm.

[0161] 5) Spin-coating PC onto PDMS film 61 PC was obtained from BM solution (chloroform solvent, 20 mg / mL) 61 BM electron transport layer, spin-coated at 1000 rpm for 60 s;

[0162] 6) In the vapor deposition chamber, at 1×10 -5 At a pressure of Pa, PC 61 A 100nm Al electrode is deposited on the BM electron transport layer to obtain a perovskite thin-film solar cell.

[0163] The performance of the obtained perovskite thin-film solar cells was tested, and the JV curve of the final device is shown below. Figure 24 As shown, detailed performance parameters of the perovskite thin-film solar cell can be found in Table 7. The average photoelectric conversion efficiency of the perovskite thin-film solar cell in this embodiment is 2.17%.

[0164] Table 7 Performance parameters of PDMS devices under VUV illumination for 10 min

[0165] Voc(V) <![CDATA[Jsc(mA / cm 2 )]]> FF PCE (%) 0.75±0.01 6.16±0.34 0.47±0.11 2.17±0.25

[0166] Compared with the prior art, the present invention provides a dense barrier layer between the perovskite active layer and the electron transport layer interface. The ion barrier layer can suppress the migration of ions from the perovskite active layer to the electron transport layer, thereby suppressing the device performance degradation caused by the decrease in the electrical properties of the electron transport layer material due to the ion migration behavior, and thus improving the stability of the device.

[0167] Furthermore, by providing a dense barrier layer between the perovskite active layer and the electron transport layer interface, the present invention can suppress the migration of ions in the perovskite active layer to the cathode, thereby suppressing the damage to the cathode caused by the ion migration behavior and improving the stability performance of the device.

[0168] Furthermore, by setting a dense barrier layer between the perovskite active layer and the electron transport layer interface, the present invention can suppress the migration of metal ions in the cathode into the perovskite active layer, thereby suppressing the damage to the perovskite active layer caused by the migration of these ions and thus improving the stability performance of the device.

[0169] In addition, by setting a dense barrier layer between the perovskite active layer and the electron transport layer interface, the present invention can prevent external water and oxygen from penetrating into the perovskite active layer, thereby protecting the perovskite active layer and improving the stability performance of the device.

[0170] It should be noted that the raw material used in this invention for preparing the ion blocking layer is organosilane, which is widely available and inexpensive. Furthermore, the organosilane is deposited on the perovskite active layer by printing, coating, or by dissolving the organosilane in an antisolvent during the preparation of the perovskite active layer. After a simple short-term VUV irradiation, the ion blocking layer can be prepared, ensuring the low-temperature, solution-compatible preparation of the entire device, which is suitable for the preparation of large-area flexible perovskite solar energy devices.

[0171] It should be understood that the above embodiments are merely illustrative of the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A perovskite thin-film solar cell, comprising a cathode, an electron transport layer, a perovskite active layer, a hole transport layer, and an anode arranged sequentially along a predetermined direction, characterized in that: A dense barrier layer is further provided between the electron transport layer and the perovskite active layer. The dense barrier layer is formed during the fabrication of the perovskite active layer using an anti-solvent method. An organosilane solution is applied to the perovskite precursor film used to form the perovskite active layer, followed by annealing. Simultaneously with the fabrication of the perovskite active layer, an organosilane film is formed on the perovskite active layer. Subsequently, the organosilane film is converted into a silicon oxide layer by vacuum ultraviolet irradiation under a nitrogen atmosphere. The wavelength of the ultraviolet light used for vacuum ultraviolet irradiation is 150-200 nm, and the irradiation time is within 30 minutes. The dense barrier layer is used to suppress ion migration between the cathode and / or the electron transport layer and the perovskite active layer.

2. The perovskite thin-film solar cell according to claim 1, characterized in that: The thickness of the dense barrier layer is 1nm-30nm.

3. The perovskite thin-film solar cell according to claim 2, characterized in that: The thickness of the dense barrier layer is 2nm-10nm.

4. The perovskite thin-film solar cell according to claim 1, characterized in that: The organosilanes mentioned include siloxanes and / or silazanes.

5. The perovskite thin-film solar cell according to claim 1, characterized in that: The electron transport layer is made of polymers and / or oxides.

6. The perovskite thin-film solar cell according to claim 5, characterized in that: The polymer includes PC 61 BM.

7. The perovskite thin-film solar cell according to claim 5, characterized in that: The oxide includes ZnO.

8. The perovskite thin-film solar cell according to claim 1, characterized in that: The thickness of the electron transport layer is 30 nm - 60 nm.

9. The perovskite thin-film solar cell according to claim 1, characterized in that: The cathode is a metal electrode.

10. The perovskite thin-film solar cell according to claim 1, characterized in that: The thickness of the cathode is 80 nm - 100 nm.

11. The perovskite thin-film solar cell according to claim 1, characterized in that: The perovskite active layer is made of ABX3, wherein A is an organic or inorganic cation; B is any one or a combination of two or more of Pb ions, Sn ions, and Ge ions; and X is a halide ion.

12. The perovskite thin-film solar cell according to claim 1, characterized in that: The thickness of the perovskite active layer is 200 nm - 500 nm.

13. The perovskite thin-film solar cell according to claim 1, characterized in that: The hole transport layer is made of organic or inorganic semiconductor materials.

14. The perovskite thin-film solar cell according to claim 13, characterized in that: The organic semiconductor material includes any one or a combination of two or more of P3CT-Na, 3,4-ethylenedioxythiophene polymer-polystyrene sulfonate, and CPE-K.

15. The perovskite thin-film solar cell according to claim 1, characterized in that: The anode is made of a transparent conductive material.

16. The perovskite thin-film solar cell according to claim 15, characterized in that: The transparent conductive material includes any one or a combination of two or more of indium tin oxide, fluorine-doped tin oxide, and Ag mesh transparent conductive film.

17. The perovskite thin-film solar cell according to claim 1, characterized in that: The anode is disposed on a transparent substrate, the transparent substrate being made of glass or PET.

18. A method for preparing a perovskite thin-film solar cell according to any one of claims 1-17, comprising the steps of fabricating a cathode, an electron transport layer, a perovskite active layer, a hole transport layer, and an anode, characterized in that, The preparation method further includes: covering the perovskite active layer with a continuous organosilane layer, and then irradiating the organosilane layer with vacuum ultraviolet light under a nitrogen atmosphere. The wavelength of the ultraviolet light used for the vacuum ultraviolet light irradiation is 150nm-200nm, and the irradiation time is within 30 minutes, thereby transforming the organosilane layer into a dense barrier layer, and then forming an electron transport layer on the dense barrier layer.

19. The preparation method according to claim 18, characterized in that: The organosilanes include siloxanes and / or silazanes.

20. The preparation method according to claim 18, characterized in that: The volume ratio of solute to solvent in the organosilane solution is 0-4%.

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