Perovskite solar cell and rapid preparation method thereof

Abstract

The application discloses a perovskite solar cell and a rapid preparation method thereof, and belongs to the field of solar cell preparation. The application provides a solar cell processing technology without separately preparing a hole transport layer. Small molecule materials are introduced into a perovskite precursor solution, so that the growth of a perovskite thin film can be controlled during a coating and film forming process, and the interface work function of the perovskite and a transparent conductive electrode is adjusted at the same time, a band gradient is formed, the charge extraction from the perovskite layer to the transparent electrode is promoted, and the charge recombination loss is reduced, so that a perovskite solar cell with a simple structure and excellent performance is obtained. Finally, based on a mixed cation perovskite, a reverse type solar cell device without a hole transport layer is prepared by using a perovskite solution with added small molecule materials, and an energy conversion efficiency of 24.3% is achieved.

Description

Technical Field

[0001] This invention belongs to the field of solar cell fabrication, specifically relating to a perovskite solar cell and its rapid fabrication method. Background Technology

[0002] Developing and utilizing clean and renewable energy is a major challenge and aspiration for human societal development. Solar energy, with its advantages of wide availability, cleanliness, and safety, is highly favored. Solar cells, which directly convert light energy into electrical energy using the photovoltaic effect, provide an effective way to utilize solar energy. Since their introduction in 2009, perovskite solar cells (PVSCs) have made rapid progress in solar energy conversion. Currently, PVSCs boast energy conversion efficiencies as high as 25% and low costs, potentially crossing the commercialization threshold and sharing, or even disrupting, the silicon-dominated photovoltaic market, thus more effectively reducing environmental pollution and the global greenhouse effect.

[0003] Currently, continuously improving the efficiency and stability of PVSCs while further simplifying the battery structure and reducing costs is an important research topic in this field. The hole transport layer material in inverted perovskite solar cell devices with superior stability often uses traditional PTAA or nickel oxide. However, PTAA is expensive, and its hydrophobic properties make it difficult to uniformly coat the perovskite solution onto its surface. While nickel oxide, a relatively inexpensive material, produces perovskite solar cells with low photoelectric conversion efficiency as the hole transport layer, it also exhibits interfacial degradation reactions with perovskite, which is detrimental to long-term stable operation. Therefore, simplifying the perovskite device structure and developing high-performance hole transport layer-free device structures is an effective way to solve these scientific problems. This not only simplifies the perovskite cell fabrication process and reduces costs but also avoids the degradation reaction between perovskite and the interface, which is beneficial for long-term stable operation of the device.

[0004] In existing technologies, although perovskite solar cells without a hole transport layer, fabricated using strongly electron-withdrawing molecular dopants (F4TCNQ) or other p-type semiconductor molecules doped with perovskite precursor solutions, have achieved a photoelectric conversion efficiency of 22%, this still lags behind fully-structured perovskite solar cells. The main reason is the work function mismatch at the interface between the perovskite and ITO or FTO electrodes. Holes generated by photoexcitation of the perovskite are difficult to be effectively extracted by the ITO or FTO electrodes, leading to severe charge recombination problems at this interface. Therefore, selecting a suitable p-type hole transport layer material to add to the perovskite precursor solution to prepare a composite perovskite solution, and then developing a rapid fabrication method for perovskite solar cell devices without a hole transport layer, is crucial for achieving efficient, stable, and low-cost perovskite solar cells. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a perovskite solar cell and its rapid fabrication method. Using the fabrication method proposed in this invention, a composite perovskite solution is prepared by pre-dissolving small molecule materials in a perovskite precursor solution. Through the strong interactions between the characteristic functional groups in the small molecule structure and the lead and transparent electrode in the perovskite solution, the perovskite crystal growth can be controlled while simultaneously modifying the work function of the perovskite-electrode interface, reducing interfacial recombination losses, and resulting in a perovskite solar cell with excellent performance and a simple structure.

[0006] The specific technical solution adopted in this invention is as follows:

[0007] In a first aspect, the present invention provides a rapid fabrication method for a perovskite solar cell, wherein a photoactive layer (3) is directly fabricated on a transparent electrode layer (2), resulting in a perovskite solar cell having, from bottom to top, a substrate (1), a transparent electrode layer (2), a photoactive layer (3), an electron transport layer (4), a work function adjustment layer (5), and a metal electrode layer (6); the photoactive layer (3) is a composite perovskite thin film, and the specific fabrication method is as follows:

[0008] Perovskite is dissolved in a first solvent to obtain a perovskite precursor solution. A small molecule material is dissolved in the above perovskite precursor solution to obtain a composite perovskite solution. The above composite perovskite solution is annealed to obtain a composite perovskite film.

[0009] Preferably, the perovskite in the perovskite precursor solution is ABX3 type perovskite, with one or more of cesium ions, methylamine cations, and formamidinium cations at site A, lead ions at site B, and one or more of chloride ions, bromide ions, and iodide ions at site X.

[0010] Preferably, the first solvent is one or a mixture of dimethyldiamide or dimethyl sulfoxide.

[0011] Preferably, the molecular framework of the above-mentioned small molecule material is one or more of carbazole-structured small molecules or triphenylamine-structured small molecules.

[0012] Furthermore, the aforementioned carbazole-based small molecules are one or more selected from carbazole phosphate 2PACz, methoxycarbazole phosphate MeO-2PACz, or methylcarbazole phosphate Me-4PACz. The aforementioned triphenylamine-based small molecules are one or more selected from LS2, LS3, LS4, LS5, LS6, or LS7, with the specific structures as follows:

[0013]

[0014] Preferably, the concentration of the small molecule material added to the above-mentioned composite perovskite solution is 1–15 mg / mL.

[0015] Furthermore, the concentration of the small molecule material added to the above-mentioned composite perovskite solution is 3–5 mg / mL.

[0016] Preferably, the annealing temperature is 90–150°C.

[0017] Furthermore, the annealing temperature described above is 100–110°C.

[0018] Preferably, the substrate material is one of glass, quartz, flexible PET, or flexible PEN. The transparent electrode layer material is indium tin oxide or fluorine-doped tin oxide. The electron transport layer is PCBM, C... 60 Or one of ZnO. The above-mentioned work function adjustment layer is BCP. The above-mentioned metal electrode layer material is one of silver, aluminum, magnesium, copper, gold, indium tin oxide or fluorine-doped tin oxide, with a thickness of 50-300 nm.

[0019] In a second aspect, the present invention provides a perovskite solar cell obtained by the rapid preparation method described in the first aspect.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] (1) This invention prepares a composite perovskite solution by adding small molecule materials to the perovskite precursor solution. The strong interaction between the characteristic groups in the structure of the small molecule materials and the lead ions in the perovskite precursor solution is used to regulate the growth of the perovskite film on the transparent electrode. At the same time, it achieves the purpose of modifying the ITO or FTO electrode and adjusting the work function of the perovskite and electrode interface. Thus, it realizes the efficient transport of holes from the active layer to the transparent electrode in the structure of a solar cell device without a hole transport layer.

[0022] (2) The average efficiency of the solar cell device prepared by the composite perovskite solution of the present invention is as high as 23% or more and the open circuit voltage is as high as 1.20V when the concentration of small molecule materials in the composite perovskite solution is in the range of 3 to 5 mg / mL. This is one of the highest voltages reported so far for perovskite solar cells with a band gap of ~1.55eV. Compared with the traditional perovskite solar cell reference device with nickel oxide or PTAA as the hole transport layer structure, the open circuit voltage and fill factor of the rapidly prepared hole transport layer-free inversion perovskite solar cell device are significantly improved.

[0023] (3) The efficiency of the hole-transport layer-free inverted solar cell device prepared rapidly from the composite perovskite solution using methoxycarbazole phosphate (MeO-2PACz) as a small molecule material in this invention can be increased from 9.20% to 24.3% (V). OC =1.20V, JSC =24.4mA / cm 2 , FF=83.0). Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of a perovskite solar cell device provided by the present invention;

[0025] Figure 2 The current-voltage curves of the perovskite solar cell device prepared using conventional high-temperature nickel oxide as the hole transport layer are provided in Comparative Example 1.

[0026] Figure 3 The current-voltage curves are for a hole-transport layer-free perovskite solar cell device prepared without the addition of small molecules from the perovskite precursor solution provided in Comparative Example 2.

[0027] Figure 4 The current-voltage curves of the hole-transport layer-free perovskite solar cell device prepared by the composite perovskite solution with added MeO-2PACz provided in Example 1 are shown.

[0028] Figure 5 The current-voltage curves of the hole-transport layer-free perovskite solar cell device prepared by the composite perovskite solution with added Me-4PACz provided in Example 2 are shown.

[0029] Figure 6 The current-voltage curves are for the hole-transport layer-free perovskite solar cell device prepared by the composite perovskite solution with added LS2 provided in Example 3.

[0030] Figure 7 The current-voltage curves are for the hole-transport layer-free perovskite solar cell device prepared by the composite perovskite solution with added LS5 provided in Example 4.

[0031] The figures are labeled as follows: substrate 1, transparent electrode layer 2, photoactive layer 3, electron transport layer 4, work function adjustment layer 5, and metal electrode layer 6. Detailed Implementation

[0032] The present invention will be further described and illustrated below with reference to the accompanying drawings and specific embodiments. The technical features of each embodiment of the present invention can be combined accordingly, provided that there is no mutual conflict.

[0033] like Figure 1As shown, the solar cell device provided by this invention does not require a hole transport layer. From bottom to top, it consists of a substrate 1, a transparent electrode layer 2, a photoactive layer 3, an electron transport layer 4, a work function adjustment layer 5, and a metal electrode layer 6. The photoactive layer 3 is a composite perovskite precursor solution containing small molecule materials, while the remaining structural layers can be adjusted according to actual conditions and are not limited.

[0034] Example 1

[0035] This embodiment provides a method for rapidly preparing perovskite solar cell devices using methoxycarbazole phosphate (MeO-2PACz) as a small molecule material, as detailed below:

[0036] (1) A first solvent is obtained by mixing dimethyl diamide (DMF) and dimethyl sulfoxide (DMSO) in a volume ratio of 4:1; perovskite raw materials FAI, MABr, PbBr, PbI2 and CsI are dissolved in the first solvent and 30 mol% methyl ammonium chloride (MACl) is added to obtain a perovskite precursor solution with a concentration of 1.4 M (CsI). 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3).

[0037] (2) A composite perovskite solution was obtained by adding 3 mg / mL of methoxycarbazole phosphate (MeO-2PACz) small molecule material to the above perovskite precursor solution.

[0038] (3) The transparent conductive glass with striped indium tin oxide (ITO) etched on the surface is cleaned by ultrasonic oscillation with cleaning agent, deionized water, acetone and isopropanol for 15 minutes, dried by nitrogen gas flow, and then treated with ultraviolet ozone for 20 minutes to obtain a clean ITO electrode.

[0039] (4) 60 μL of composite perovskite solution was added dropwise to the ITO electrode for spin coating at a spin coating rate of 4000 rpm for 40 s. 30 s after the spin coating started, 120 μL of isopropanol was added dropwise. After the spin coating stopped, the wet perovskite film was placed on a hot stage at 100°C and annealed for 30 min to obtain a composite perovskite film. After cooling, an ethylenediamine solution was spin-coated at 4000 rpm. The composite perovskite film was then placed on a hot stage at 70°C and annealed for 5 min. After cooling, the solution was spin-coated at 5000 rpm. An organic ammonium salt solution (isopropanol, 2 mg / mL) was spin-coated at a certain speed. The film was annealed on a hot plate at 100°C for 5 min. After cooling, PCBM (chlorobenzene, 20 mg / mL) and BCP (ethanol, 0.5 mg / mL) were spin-coated at 3000 rpm. Finally, a 100 nm thick Ag electrode was deposited on the BCP using an evaporator to obtain Cs containing MeO-2PACz small molecule material. 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3 is a perovskite solar cell device with a hole transport layer structure for the active layer.

[0040] At a light intensity of 100mW / cm 2 Under AM1.5G simulated sunlight irradiation, the current-voltage curves of the aforementioned solar cell devices were tested, as shown below. Figure 4 As shown, the open-circuit voltage (V) of this solar cell device OC The voltage is 1.20V, and the short-circuit current density (Jsc) is 24.4mA / cm². 2 The fill factor (FF) is 83.0 and the power conversion efficiency (PCE) is 24.3%.

[0041] Example 2

[0042] This embodiment provides a method for rapidly preparing perovskite solar cell devices using methylcarbazole phosphate (Me-4PACz) as a small molecule material, as detailed below:

[0043] (1) A first solvent is obtained by mixing dimethyl diamide (DMF) and dimethyl sulfoxide (DMSO) in a volume ratio of 4:1; perovskite raw materials FAI, MABr, PbBr, PbI2 and CsI are dissolved in the first solvent and 30 mol% methyl ammonium chloride (MACl) is added to obtain a perovskite precursor solution with a concentration of 1.4 M (CsI). 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br0.05 )3).

[0044] (2) Add 3 mg / mL of methylcarbazole phosphate (Me-4PACz) small molecule material to the above perovskite precursor solution to obtain a composite perovskite solution.

[0045] (3) The transparent conductive glass with striped indium tin oxide (ITO) etched on the surface is cleaned by ultrasonic oscillation with cleaning agent, deionized water, acetone and isopropanol for 15 minutes, dried by nitrogen gas flow, and then treated with ultraviolet ozone for 20 minutes to obtain a clean ITO electrode.

[0046] (4) 60 μL of composite perovskite solution was added dropwise to the ITO electrode for spin coating at a spin coating rate of 4000 rpm for 40 s. 30 s after the spin coating began, 120 μL of isopropanol was added dropwise. After the spin coating stopped, the wet perovskite film was annealed on a hot plate at 100°C for 30 min to obtain a composite perovskite film. After cooling, an ethylenediamine solution was spin-coated at 4000 rpm. The composite perovskite film was then annealed on a hot plate at 70°C for 5 min. After cooling, the film was spin-coated with 5000 rpm. An organic ammonium salt solution (isopropanol, 2 mg / mL) was spin-coated at a speed of m. The film was then annealed on a hot plate at 100°C for 5 min. After cooling, PCBM (chlorobenzene, 20 mg / mL) and BCP (ethanol, 0.5 mg / mL) were spin-coated at 3000 rpm. Finally, a 100 nm thick Ag electrode was deposited on the BCP using an evaporator to obtain Cs containing Me-4PACz small molecule material. 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3 is a perovskite solar cell device with a hole transport layer structure for the active layer.

[0047] At a light intensity of 100mW / cm 2 Under simulated sunlight illumination using AM1.5G, the current-voltage curve of the device was tested, as shown below. Figure 5 As shown, the open-circuit voltage (V) of this solar cell device OC The voltage is 1.18V, and the short-circuit current density (Jsc) is 22.4mA / cm². 2 The fill factor (FF) is 73.5 and the power conversion efficiency (PCE) is 19.58%.

[0048] Example 3

[0049] This embodiment provides a method for rapidly preparing perovskite solar cell devices using triphenylamine phosphate (LS2) as a small molecule material, as detailed below:

[0050] (1) A first solvent is obtained by mixing dimethyl diamide (DMF) and dimethyl sulfoxide (DMSO) in a volume ratio of 4:1; perovskite raw materials FAI, MABr, PbBr, PbI2 and CsI are dissolved in the first solvent and 30 mol% methyl ammonium chloride (MACl) is added to obtain a perovskite precursor solution with a concentration of 1.4 M (CsI). 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3).

[0051] (2) A composite perovskite solution was obtained by adding 3 mg / mL of triphenylamine phosphate (LS2) small molecule material to the above perovskite precursor solution.

[0052] (3) The transparent conductive glass with striped indium tin oxide (ITO) etched on the surface is cleaned by ultrasonic oscillation with cleaning agent, deionized water, acetone and isopropanol for 15 minutes, dried by nitrogen gas flow, and then treated with ultraviolet ozone for 20 minutes to obtain a clean ITO electrode.

[0053] (4) 60 μL of composite perovskite solution was added dropwise to the ITO electrode for spin coating at a spin coating rate of 4000 rpm for 40 s. 30 s after the spin coating began, 120 μL of isopropanol was added dropwise. After spin coating stopped, the composite perovskite wet film was annealed on a hot plate at 100°C for 30 min to obtain a composite perovskite film. After cooling, an ethylenediamine solution was spin-coated at 4000 rpm. The composite perovskite film was then annealed on a hot plate at 70°C for 5 min. After cooling, a 500 μL solution was used for spin coating. An organic ammonium salt solution (isopropanol, 2 mg / mL) was spin-coated at 0 rpm. The film was then annealed on a hot plate at 100°C for 5 min. After cooling, PCBM (chlorobenzene, 20 mg / mL) and BCP (ethanol, 0.5 mg / mL) were spin-coated at 3000 rpm. Finally, a 100 nm thick Ag electrode was deposited on the BCP using an evaporator to obtain Cs containing LS2 small molecule material. 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3 is a perovskite solar cell device with a hole transport layer structure for the active layer.

[0054] At a light intensity of 100mW / cm 2 Under simulated sunlight illumination using AM1.5G, the current-voltage curve of the device was tested, as shown below. Figure 6As shown, the open-circuit voltage (V) of this solar cell device OC The voltage is 1.14V, and the short-circuit current density (Jsc) is 22.2mA / cm². 2 The fill factor (FF) is 76.1 and the power conversion efficiency (PCE) is 19.1%.

[0055] Example 4

[0056] This embodiment provides a method for rapidly preparing perovskite solar cell devices using triphenylamine cyanocarboxylic acid (LS5) as a small molecule material, as detailed below:

[0057] (1) A first solvent is obtained by mixing dimethyl diamide (DMF) and dimethyl sulfoxide (DMSO) in a volume ratio of 4:1; perovskite raw materials FAI, MABr, PbBr, PbI2 and CsI are dissolved in the first solvent and 30 mol% methyl ammonium chloride (MACl) is added to obtain a perovskite precursor solution with a concentration of 1.4 M (CsI). 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3).

[0058] (2) A composite perovskite solution was obtained by adding 3 mg / mL of triphenylamine cyanocarboxylic acid (LS5) small molecule material to the above perovskite precursor solution.

[0059] (3) The transparent conductive glass with striped indium tin oxide (ITO) etched on the surface is cleaned by ultrasonic oscillation with cleaning agent, deionized water, acetone and isopropanol for 15 minutes, dried by nitrogen gas flow, and then treated with ultraviolet ozone for 20 minutes to obtain a clean ITO electrode.

[0060] (4) 60 μL of composite perovskite solution was added dropwise to the ITO electrode for spin coating at a spin coating rate of 4000 rpm for 40 s. 30 s after the spin coating began, 120 μL of isopropanol was added dropwise. After spin coating stopped, the composite perovskite wet film was annealed on a hot plate at 100°C for 30 min to obtain a composite perovskite film. After cooling, an ethylenediamine solution was spin-coated at 4000 rpm. The composite perovskite film was then annealed on a hot plate at 70°C for 5 min. After cooling, a 500 μL solution was used for spin coating. An organic ammonium salt solution (isopropanol, 2 mg / mL) was spin-coated at 0 rpm. The film was then annealed on a hot plate at 100°C for 5 min. After cooling, PCBM (chlorobenzene, 20 mg / mL) and BCP (ethanol, 0.5 mg / mL) were spin-coated at 3000 rpm. Finally, a 100 nm thick Ag electrode was deposited on the BCP using an evaporator to obtain Cs containing LS5 small molecule material. 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3 is a perovskite solar cell device with a hole transport layer structure for the active layer.

[0061] At a light intensity of 100mW / cm 2 Under simulated sunlight illumination using AM1.5G, the current-voltage curve of the device was tested, as shown below. Figure 7 As shown, the open-circuit voltage (V) of this solar cell device OC The voltage is 1.11V, and the short-circuit current density (Jsc) is 21.1mA / cm². 2 The fill factor (FF) is 73.3 and the power conversion efficiency (PCE) is 17.2%.

[0062] Comparative Example 1

[0063] This comparative example provides a method for fabricating perovskite solar cell devices using conventional high-temperature nickel oxide as the hole transport layer, as detailed below:

[0064] (1) A first solvent is obtained by mixing dimethyl diamide (DMF) and dimethyl sulfoxide (DMSO) in a volume ratio of 4:1; perovskite raw materials FAI, MABr, PbBr, PbI2 and CsI are dissolved in the first solvent and 30 mol% methyl ammonium chloride (MACl) is added to obtain a perovskite precursor solution with a concentration of 1.4 M (CsI). 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3).

[0065] (2) The transparent conductive glass with striped indium tin oxide (ITO) etched on the surface is cleaned by ultrasonic oscillation with cleaning agent, deionized water, acetone and isopropanol for 15 minutes, dried by nitrogen gas flow, and then treated with ultraviolet ozone for 20 minutes to obtain a clean ITO electrode.

[0066] (3) Spin-coat a layer of nickel oxide (NiOx) solution onto the cleaned ITO electrode. Spin-coat parameters are 4000 rpm for 30 s. Anneal at 110 °C for 15 min. Then transfer to a hot stage at 350 °C for sintering for 1 h to obtain a hole transport layer.

[0067] (4) 60 μL of the above perovskite precursor solution was dropped onto the nickel oxide hole transport layer. The spin coating rate was set to 4000 rpm for 40 s. 30 s after the spin coating started, 120 μL of isopropanol was dropped. After the spin coating stopped, the film was placed on a hot stage at 100°C and annealed for 30 min. After cooling, the ethylenediamine solution was spin coated at 4000 rpm. The film was placed on a hot stage at 70°C and annealed for 5 min. After cooling, the organic ammonium salt solution (isopropanol, concentration 2 mg / mL) was spin coated at 5000 rpm. The film was placed on a hot stage at 100°C and annealed for 5 min. After cooling, PCBM (chlorobenzene, concentration 20 mg / mL) and BCP (ethanol, concentration 0.5 mg / mL) were spin coated at 3000 rpm. Finally, an Ag electrode with a thickness of 100 nm was deposited on the BCP using an evaporator to obtain a perovskite solar cell device containing a hole transport layer.

[0068] At a light intensity of 100mW / cm 2 Under simulated sunlight illumination using AM1.5G, the current-voltage curve of the device was tested, as shown below. Figure 2 As shown, the open-circuit voltage (V) of this device OC The voltage is 1.11V, and the short-circuit current density (Jsc) is 23.0mA / cm². 2 The fill factor (FF) is 75.3 and the power conversion efficiency (PCE) is 19.3%.

[0069] Comparative Example 2

[0070] This comparative example provides a method for rapidly preparing perovskite solar cell devices without adding small molecules, as detailed below:

[0071] (1) A first solvent is obtained by mixing dimethyl diamide (DMF) and dimethyl sulfoxide (DMSO) in a volume ratio of 4:1; perovskite raw materials FAI, MABr, PbBr, PbI2 and CsI are dissolved in the first solvent and 30 mol% methyl ammonium chloride (MACl) is added to obtain a perovskite precursor solution with a concentration of 1.4 M (CsI). 0.05 (FA 0.95 MA 0.05 ) 0.95 Pb(I 0.95 Br 0.05 )3).

[0072] (2) The transparent conductive glass with striped indium tin oxide (ITO) etched on the surface is cleaned by ultrasonic oscillation with cleaning agent, deionized water, acetone and isopropanol for 15 minutes, dried by nitrogen gas flow, and then treated with ultraviolet ozone for 20 minutes to obtain a clean ITO electrode.

[0073] (3) 60 μL of the above perovskite precursor solution was dropped onto the ITO electrode. The spin coating rate was set to 4000 rpm for 40 s. 30 s after the spin coating started, 120 μL of isopropanol was dropped. After the spin coating stopped, the film was placed on a hot stage at 100°C and annealed for 30 min. After cooling, the ethylenediamine solution was spin coated at 4000 rpm. The film was placed on a hot stage at 70°C and annealed for 5 min. After cooling, the organic ammonium salt solution (isopropanol, concentration 2 mg / mL) was spin coated at 5000 rpm. The film was placed on a hot stage at 100°C and annealed for 5 min. After cooling, PCBM (chlorobenzene, concentration 20 mg / mL) and BCP (ethanol, concentration 0.5 mg / mL) were spin coated at 3000 rpm. Finally, an Ag electrode with a thickness of 100 nm was deposited on the BCP using a vapor deposition apparatus to obtain a perovskite solar cell device without a hole transport layer.

[0074] At a light intensity of 100mW / cm 2 Under simulated sunlight illumination using AM1.5G, the current-voltage curve of the device was tested, as shown below. Figure 3 As shown, the open-circuit voltage (V) of this device OC The voltage is 1.06V, and the short-circuit current density (Jsc) is 19.5mA / cm². 2 The fill factor (FF) is 44.5 and the power conversion efficiency (PCE) is 9.20%.

[0075] This invention provides a solar cell fabrication process that eliminates the need for a separate hole transport layer. By introducing small-molecule materials into the perovskite precursor solution, the growth of the perovskite film can be controlled during the coating process. Simultaneously, the work function at the interface between the perovskite and the transparent conductive electrode is adjusted, creating an energy band gradient. This promotes charge extraction from the perovskite layer to the transparent electrode, reducing charge recombination losses, thereby obtaining a perovskite solar cell with a simple structure and excellent performance. Finally, an inverted solar cell device without a hole transport layer, based on mixed-cation perovskite and using a perovskite solution with added small-molecule materials, achieved a power conversion efficiency of 24.3%.

[0076] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the invention. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, all technical solutions obtained through equivalent substitution or transformation fall within the protection scope of the present invention.

Claims

1. A rapid fabrication method for perovskite solar cells, characterized in that, By directly preparing a photoactive layer (3) on the transparent electrode layer (2), a perovskite solar cell is obtained by sequentially stacking a substrate (1), a transparent electrode layer (2), a photoactive layer (3), an electron transport layer (4), a work function adjustment layer (5), and a metal electrode layer (6) from bottom to top; the photoactive layer (3) is a composite perovskite thin film, and the specific preparation method is as follows: Perovskite was dissolved in a first solvent to obtain a perovskite precursor solution; a small molecule material was dissolved in the perovskite precursor solution to obtain a composite perovskite solution; the composite perovskite solution was annealed at 100°C for 30 min to obtain a composite perovskite film; after cooling, an ethylenediamine solution was spin-coated, and the entire film was annealed on a hot plate at 70°C for 5 min; after cooling, an organic ammonium salt solution was spin-coated, and the entire film was annealed on a hot plate at 100°C for 5 min. The perovskite in the perovskite precursor solution is ABX3 type perovskite, with one or more of cesium ions, methylamine cations, and formamidinium cations at the A site, lead ions at the B site, and one or more of chloride ions, bromide ions, and iodide ions at the X site. The molecular framework of the small molecule material is one or more of carbazole-based or triphenylamine-based small molecules; the carbazole-based small molecule is one or more of carbazole phosphate 2PACz, methoxycarbazole phosphate MeO-2PACz, or methylcarbazole phosphate Me-4PACz; the triphenylamine-based small molecule is one or more of LS2, LS3, LS4, LS5, LS6, or LS7, with the specific structure as follows: 。 2. The rapid fabrication method for a perovskite solar cell according to claim 1, characterized in that, The first solvent is one of dimethyldiamide or dimethyl sulfoxide, or a mixture of both.

3. The rapid fabrication method of a perovskite solar cell according to claim 1, characterized in that, The concentration of the small molecule material added to the composite perovskite solution is 1~15 mg / mL.

4. A rapid fabrication method for a perovskite solar cell according to claim 3, characterized in that, The concentration of small molecule materials added to the composite perovskite solution is 3~5 mg / mL.

5. The rapid fabrication method for a perovskite solar cell according to claim 1, characterized in that, The substrate (1) is made of one of glass, quartz, flexible PET or flexible PEN.

6. The rapid fabrication method for a perovskite solar cell according to claim 1, characterized in that, The transparent electrode layer (2) is made of indium tin oxide or fluorine-doped tin oxide.

7. The rapid fabrication method for a perovskite solar cell according to claim 1, characterized in that, The electron transport layer (4) is PCBM, C 60 Or one of ZnO.

8. The rapid fabrication method for a perovskite solar cell according to claim 1, characterized in that, The power function adjustment layer (5) is a BCP.

9. The rapid fabrication method of a perovskite solar cell according to claim 1, characterized in that, The metal electrode layer (6) is made of one of the following materials: silver, aluminum, magnesium, copper, gold, indium tin oxide or fluorine-doped tin oxide, and has a thickness of 50~300nm.

10. A perovskite solar cell obtained by the rapid preparation method according to any one of claims 1 to 9.

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