High-performance semitransparent perovskite solar cell device and preparation method thereof

Abstract

The invention relates to the technical field of solar cell preparation, and discloses a high-performance semitransparent perovskite solar cell device and a preparation method thereof.The preparation method comprises the steps that an alpha-SnO2 colloidal solution, a beta-SnO2 colloidal solution, a perovskite precursor solution, a PMMA solution and a Spiro-OMeTAD solution are sequentially coated on an ITO coating glass substrate, finally, ultrathin metal electrodes MoO3 and Au are used as top electrodes, and the ITO coating glass substrate is coated with a high-performance semitransparent perovskite solar cell device is prepared. And the high-performance semitransparent perovskite solar cell device is obtained. According to the invention, the 3, 5-difluoroaniline hydrochloride is added into the perovskite precursor solution, so that the energy level alignment of the perovskite light absorption layer and the electron and hole transport layer is optimized, and the extraction of charges at an interface is effectively promoted. The photoelectric conversion efficiency of the semitransparent perovskite solar cell is 16.32%, the average visible light transmittance is 31.69%, and the light utilization efficiency of broken recording is 5.17%.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cell preparation, and in particular to a high-performance semi-transparent perovskite solar cell device and a preparation method thereof. Background Art

[0002] Semi-transparent perovskite solar cells (ST-PSCs) have attracted widespread attention due to their potential applications in tandem solar cells (TSCs), vehicle integrated photovoltaics (VIPV) and building integrated photovoltaics (BIPV). However, achieving the optimal balance between photoelectric conversion efficiency (PCE) and average visible light transmittance (AVT) remains a key challenge. Therefore, the design of high-performance ST-PSCs is more difficult than traditional opaque perovskite solar cells (PSCs). In order to comprehensively evaluate the performance of ST-PSCs, light utilization efficiency (LUE = PCE × AVT) has become a key indicator. Considering that high AVT reduces light absorption, it inevitably leads to low short-circuit current (J SC ), increase the open circuit voltage (V OC ) is a more effective strategy to achieve high PCE while maintaining high AVT.

[0003] With high theoretical V OC Wide bandgap perovskite (E g >1.7eV) are ideal materials for ST-PSCs because they can transmit light of longer wavelengths while effectively absorbing light of shorter wavelengths (<730nm). Among them, all-inorganic perovskites (CsPbX3) exhibit excellent stability and optical transparency and are one of the most promising materials for achieving high-performance ST-PSCs. In particular, CsPbI2Br has a band gap of approximately 1.9eV and a theoretical V OC The Vmax is about 1.6 V, and high AVT (>20%) can be achieved without excessively reducing the thickness of the perovskite layer. In addition, additive engineering has been shown to increase V by passivating defects and suppressing non-radiative recombination. OC However, the actual V OC Value and Theory V OC The gap between the values ​​indicates that the loss of open-circuit voltage due to defect-induced non-radiative recombination in CsPbI2Br films is still a significant issue. Summary of the Invention

[0004] In light of this, the present invention proposes a high-performance semi-transparent perovskite solar cell device and its preparation method, aiming to overcome the current technical bottleneck of the mutual constraints between photoelectric conversion efficiency (PCE) and visible light transmittance (AVT), thereby significantly improving light utilization efficiency (LUE). By rationally designing transparent electrodes and introducing functional additives, high power conversion efficiency is achieved while maintaining an appropriate average visible transmittance, successfully achieving a highly efficient semi-transparent photovoltaic device with excellent light utilization efficiency.

[0005] The present invention provides a method for preparing a high-performance semi-transparent perovskite solar cell device, comprising the following steps:

[0006] Lead bromide, cesium iodide, lead iodide, methylamine hydrochloride and 3,5-difluoroaniline hydrochloride are dissolved in a specific solvent to obtain a perovskite precursor solution;

[0007] dissolving polymethyl methacrylate in isopropyl alcohol to obtain a polymethyl methacrylate solution;

[0008] Dissolving 2,2',7,7'-tetrakis[n,n-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene, a lithium bis(trifluoromethanesulfonyl)imide solution, and 4-tert-butylpyridine in chlorobenzene to obtain a 2,2',7,7'-tetrakis[n,n-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene solution;

[0009] Ultrasonic treatment is performed on an ITO-coated glass substrate, and then α-SnO2 and β-SnO2 colloidal solutions are sequentially coated on the ITO-coated glass substrate to obtain a pretreated ITO-coated glass substrate;

[0010] performing a first annealing treatment on the pretreated ITO-coated glass substrate, and then coating the perovskite precursor solution on the pretreated ITO-coated glass substrate to obtain a wet film;

[0011] The wet film is subjected to a second annealing treatment, and then coated with the polymethyl methacrylate solution and 2,2',7,7'-tetrakis[n,n-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene solution, and finally MoO3 and Au electrodes are prepared by thermal evaporation to obtain the high-performance semi-transparent perovskite solar cell device.

[0012] Furthermore, the mass ratio of the lead bromide, cesium iodide, lead iodide, methylamine hydrochloride and 3,5-difluoroaniline hydrochloride is (150-300): (20-60): (600-800): (1-7): (5-10).

[0013] Furthermore, the concentration of the perovskite precursor solution is 0.1-1 M, and the specific solvent is one or more of DMF, DMSO or NMP.

[0014] Furthermore, the concentration of the polymethyl methacrylate solution is 0.1-1 mg / mL, and the volume ratio of the lithium bis(trifluoromethanesulfonyl)imide solution to 4-tert-butylpyridine is (20-60):(10-40).

[0015] Furthermore, the ultrasonic treatment is specifically: ultrasonic treatment in acetone, deionized water and ethanol for 5 to 30 minutes respectively.

[0016] Furthermore, the coating method is spin coating, the speed is 4000 rpm / min, and the time is 25 to 50 s.

[0017] Furthermore, during the coating process, one of ethyl acetate, chlorobenzene, isopropyl alcohol, ether or toluene is used as an anti-solvent.

[0018] Furthermore, the first annealing treatment is performed at a temperature of 120-180° C. and for a time of 20-40 min; the second annealing treatment is performed in a nitrogen-filled environment at a temperature of 120-180° C. and for a time of 10-40 min.

[0019] Furthermore, the 3,5-difluoroaniline hydrochloride contains one or more of -F, -Cl, -NH2, -COOH, -OH or -C=O functional groups.

[0020] The present invention also provides a high-performance semi-transparent perovskite solar cell device prepared by the preparation method of the high-performance semi-transparent perovskite solar cell device described in the above technical solution.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) The present invention selects CsPbI2Br perovskite material as the light-absorbing layer of the semi-transparent perovskite solar cell to take into account the trade-off between the average visible light transmittance and the photoelectric conversion efficiency of the semi-transparent cell.

[0023] (2) The present invention introduces 3,5-difluoro-benzoamidine hydrochloride (DFBA) into the CsPbI2Br perovskite precursor solution, optimizes the energy level alignment of the perovskite light-absorbing layer and the electron and hole transport layers, effectively promotes the extraction of charges at the interface, and achieves the highest average visible light transmittance of 16.32% and light utilization efficiency of 5.17% for the semi-transparent perovskite solar cell; in addition, the device of the present invention exhibits significant thermal stability. After 600 hours in a nitrogen atmosphere at 85°C, its initial photoelectric conversion efficiency is still 88%.

[0024] (3) The present invention selects two tin oxide layers with different energy levels, α-SnO2 and α-SnO2, as the electron transfer layer of the semi-transparent perovskite solar cell. The favorable energy level arrangement at the ITO / α-SnO2 / α-SnO2 / perovskite interface reduces the energy barrier, promotes the effective transfer of electrons from perovskite to ITO, and minimizes the interface recombination loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0026] Figure 1 The molecular structure and charge distribution diagram of 3,5-difluoroaniline hydrochloride of the present invention;

[0027] Figure 2 The X-ray diffraction analysis diagrams of the experimental group and the control group of the present invention;

[0028] Figure 3 The SEM images of the experimental group and the control group of the present invention;

[0029] Figure 4 AFM images of the experimental group and the control group of the present invention;

[0030] Figure 5 2D GIWAXS images of the experimental group and the control group of the present invention;

[0031] Figure 6 Steady-state PL spectra of the experimental group and the control group on glass and SnO2 layer;

[0032] Figure 7 2D PL mapping measurements of the experimental group and the control group on glass;

[0033] Figure 8 TRPL images of the experimental group and the control group of the present invention on the SnO2 layer and Spiro-OMeTAD;

[0034] Figure 9 The ultraviolet photoelectron spectrum analysis diagram of the experimental group and the control group of the present invention;

[0035] Figure 10 is the Mott-Schottky plot of the experimental group and the control group of the present invention;

[0036] Figure 11 Nyquist plots of the experimental group and the control group of the present invention;

[0037] Figure 12 This is a relationship diagram between the open circuit voltage and light intensity of the experimental group and the control group of the present invention;

[0038] Figure 13 The diagram shows the space charge limited current measurement results of pure electron and pure hole devices;

[0039] Figure 14 The theoretical model and adsorption energy diagram of the interaction between DFBA and perovskite molecules;

[0040] Figure 15 X-ray photoelectron spectroscopy analysis diagram of DFBA and experimental group perovskite;

[0041] Figure 16 Fourier transform infrared spectrum analysis diagram of DFBA and perovskite of experimental group;

[0042] Figure 17 GIXRD spectra and sin2ψ-2θ linear fitting diagrams of the experimental group and the control group at different tilt angles of the present invention;

[0043] Figure 18 The figure shows the physical object and performance parameter diagram of the battery device in the experimental group of the present invention;

[0044] Figure 19 Schematic diagram of the structure, JV curve and transmittance of ST-PSCs prepared in the present invention;

[0045] Figure 20 Statistical distribution of photovoltaic parameters of the control group and experimental group of battery devices of the present invention;

[0046] Figure 21 This is a comparison chart of the AVT-PCE of the experimental group of the present invention and the AVT-PCE of the prior art;

[0047] Figure 22 Schematic diagram of the stability of the experimental group and the control group of the present invention at different temperatures. DETAILED DESCRIPTION

[0048] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art. It should be noted that, unless there is a conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0049] The present invention provides a method for preparing a high-performance semi-transparent perovskite solar cell device, comprising the following steps:

[0050] Lead bromide (PbBr2), cesium iodide (PbBr2), lead iodide (PbBr2), methylamine hydrochloride (MACl) and 3,5-difluoroaniline hydrochloride (DFBA) are dissolved in a specific solvent to obtain a perovskite precursor solution;

[0051] dissolving polymethyl methacrylate (PMMA) in isopropyl alcohol (IPA) to obtain a polymethyl methacrylate (PMMA) solution;

[0052] 2,2',7,7'-tetrakis[n,n-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) solution and 4-tert-butylpyridine (4-tBP) were dissolved in chlorobenzene (CB) to obtain 2,2',7,7'-tetrakis[n,n-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD) solution;

[0053] Ultrasonic treatment is performed on an ITO-coated glass substrate, and then α-SnO2 and β-SnO2 colloidal solutions are sequentially coated on the ITO-coated glass substrate to obtain a pretreated ITO-coated glass substrate;

[0054] performing a first annealing treatment on the pretreated ITO-coated glass substrate, and then coating the perovskite precursor solution on the pretreated ITO-coated glass substrate to obtain a wet film;

[0055] The wet film is subjected to a second annealing treatment, and then coated with the polymethyl methacrylate (PMMA) solution and 2,2',7,7'-tetrakis[n,n-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD) solution. Finally, MoO3 and Au electrodes are prepared by thermal evaporation to obtain the high-performance semi-transparent perovskite solar cell device.

[0056] Lead bromide (PbBr2), cesium iodide (PbBr2), lead iodide (PbBr2), methylamine hydrochloride (MACl) and 3,5-difluoroaniline hydrochloride (DFBA) are dissolved in a specific solvent to obtain a perovskite precursor solution;

[0057] The 3,5-difluoro-benzoamidine hydrochloride (DFBA) introduced in this invention optimizes the energy level alignment between the perovskite light-absorbing layer and the electron and hole transport layers, effectively promoting charge extraction at the interface. This results in a semi-transparent perovskite solar cell with a maximum average visible light transmittance of 16.32% and a light utilization efficiency of 5.17%. Furthermore, the device produced by this invention exhibits significant thermal stability, with an initial photoelectric conversion efficiency of 88% after 600 hours at 85°C in a nitrogen atmosphere.

[0058] In the present invention, the 3,5-difluoroaniline hydrochloride preferably contains one or more of -F, -Cl, -NH2, -COOH, -OH or -C=O functional groups.

[0059] In the present invention, the mass ratio of the lead bromide, cesium iodide, lead iodide, methylamine hydrochloride and 3,5-difluoroaniline hydrochloride is preferably (150-300):(20-60):(600-800):(1-7):(5-10), and more preferably (150-200):(20-40):(600-700):(1-3):(5-7).

[0060] In the present invention, the concentration of the perovskite precursor solution is preferably 0.1 to 1 M, more preferably 0.1 to 0.5 M, and the specific solvent is preferably one or more of DMF, DMSO or NMP.

[0061] When multiple solvents are used in the perovskite precursor solution of the present invention, the ratio between the multiple solvents is not limited.

[0062] dissolving polymethyl methacrylate (PMMA) in isopropyl alcohol (IPA) to obtain a polymethyl methacrylate (PMMA) solution;

[0063] In the present invention, the concentration of the polymethyl methacrylate (PMMA) solution is preferably 0.1 to 1 mg / mL;

[0064] 2,2',7,7'-tetrakis[n,n-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD), lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) solution and 4-tert-butylpyridine (4-tBP) were dissolved in chlorobenzene (CB) to obtain 2,2',7,7'-tetrakis[n,n-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD) solution;

[0065] The lithium bis(trifluoromethanesulfonyl)imide (Li-TFSI) solution is prepared by dissolving 260 mg of Li-TFSI powder in 1 mL of ACN. The volume ratio of the lithium bis(trifluoromethanesulfonyl)imide solution to 4-tert-butylpyridine is preferably (20-60):(10-40), and more preferably (20-40):(10-30).

[0066] Ultrasonic treatment is performed on an ITO-coated glass substrate, and then α-SnO2 and β-SnO2 colloidal solutions are sequentially coated on the ITO-coated glass substrate to obtain a pretreated ITO-coated glass substrate;

[0067] The present invention selects two tin oxide layers with different energy levels, α-SnO2 and α-SnO2, as the electron transfer layer of the semi-transparent perovskite solar cell. The favorable energy level arrangement at the ITO / α-SnO2 / α-SnO2 / perovskite interface reduces the energy barrier, promotes the efficient transfer of electrons from perovskite to ITO, and minimizes interface recombination losses;

[0068] In the present invention, the ultrasonic treatment is preferably: ultrasonic treatment in acetone, deionized water and ethanol for 5 to 30 minutes respectively.

[0069] In the present invention, the coating method is preferably spin coating, with a speed of 4000 rpm / min and a time of 25 to 50 s.

[0070] In the present invention, one of ethyl acetate, chlorobenzene, isopropyl alcohol, ether or toluene is used as an anti-solvent in the coating process.

[0071] The present invention controls the supersaturation of the solution by adding an anti-solvent, thereby inhibiting the nucleation of crystals and promoting their growth process. Specifically, the anti-solvent is added dropwise during the coating process of the perovskite film, specifically 15 seconds before the end of spin coating.

[0072] performing a first annealing treatment on the pretreated ITO-coated glass substrate, and then coating the perovskite precursor solution on the pretreated ITO-coated glass substrate to obtain a wet film;

[0073] In the present invention, the first annealing treatment is preferably performed at a temperature of 120-180° C. for 20-40 min, more preferably at a temperature of 120-150° C. for 20-30 min.

[0074] The wet film is subjected to a second annealing treatment, and then coated with the polymethyl methacrylate (PMMA) solution and 2,2',7,7'-tetrakis[n,n-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (Spiro-OMeTAD) solution, and finally MoO3 and Au electrodes are prepared by thermal evaporation to obtain the high-performance semi-transparent perovskite solar cell device;

[0075] The present invention also prepares ultrathin semi-transparent metal electrodes MoO3 and Au as top electrodes;

[0076] The second annealing treatment is preferably performed in a nitrogen-filled environment at a temperature of 120-180° C. for 10-40 minutes, more preferably at a temperature of 120-150° C. for 10-20 minutes.

[0077] The present invention also provides a high-performance semi-transparent perovskite solar cell device prepared by the preparation method of the high-performance semi-transparent perovskite solar cell device described in the above technical solution.

[0078] Example 1

[0079] (1) 232.16 mg of PbBr2, 38.97 mg of CsI, 712.30 mg of PbI2, 3.38 mg of MACl, and 7.70 mg of DFBA were dissolved in a mixed solvent to obtain a perovskite precursor solution. The mixed solvent included 600 μL of DMF and 400 μL of DMSO to obtain a perovskite precursor solution;

[0080] (2) dissolving PMMA in IPA to obtain a PMMA solution with a concentration of 0.4 mg / mL;

[0081] (3) 72.3 mg of Spiro-OMeTAD, 35 μL of Li-TFSI (260 mg of Li-TFSI powder dissolved in 1 mL of ACN), and 29 μL of 4-tBP were dissolved in 1 mL of CB to obtain a Spiro-OMeTAD solution;

[0082] (4) ultrasonically treating the ITO-coated glass substrate in acetone, deionized water, and ethanol for 15 minutes, respectively, and then spin-coating the α-SnO2 and β-SnO2 colloidal solutions on the ITO-coated glass substrate at a speed of 4000 rpm / min for 30 seconds to obtain a pretreated ITO-coated glass substrate;

[0083] (5) annealing the obtained pretreated ITO-coated glass substrate at a temperature of 165° C. for 30 minutes, and then spin-coating a perovskite precursor solution on the pretreated ITO-coated glass substrate to obtain a wet film;

[0084] (6) The wet film was placed in a nitrogen-filled glove box for annealing at a temperature of 150°C for 20 minutes, and then spin-coated with the PMMA solution and the Spiro-OMeTAD solution for 30 seconds at a speed of 4000 rpm / min. Finally, 5 nm MoO3 and 8 nm Au electrodes were prepared by thermal evaporation to obtain a high-performance semi-transparent perovskite solar cell device.

[0085] Example 2

[0086] (1) 300 mg of PbBr2, 60 mg of CsI, 800 mg of PbI2, 7 mg of MACl, and 10 mg of DFBA were dissolved in a mixed solvent to obtain a perovskite precursor solution. The mixed solvent included 600 μL of DMF and 400 μL of DMSO to obtain a perovskite precursor solution;

[0087] (2) dissolving PMMA in IPA to obtain a PMMA solution with a concentration of 1 mg / mL;

[0088] (3) 72.3 mg of Spiro-OMeTAD, 35 μL of Li-TFSI (260 mg of Li-TFSI dissolved in 1 mL of ACN), and 29 μL of 4-tBP were dissolved in 1 mL of CB to obtain a Spiro-OMeTAD solution;

[0089] (4) ultrasonically treating the ITO-coated glass substrate in acetone, deionized water, and ethanol for 15 minutes, respectively, and then spin-coating the α-SnO2 and β-SnO2 colloidal solutions on the ITO-coated glass substrate at a speed of 4000 rpm / min for 30 seconds to obtain a pretreated ITO-coated glass substrate;

[0090] (5) annealing the obtained pretreated ITO-coated glass substrate at a temperature of 180° C. for 40 minutes, and then spin-coating a perovskite precursor solution on the pretreated ITO-coated glass substrate to obtain a wet film;

[0091] (6) The wet film was placed in a nitrogen-filled glove box for annealing at a temperature of 180°C for 40 minutes, and then spin-coated with the PMMA solution and the Spiro-OMeTAD solution for 50 seconds at a speed of 4000 rpm / min. Finally, 5 nm MoO3 and 8 nm Au electrodes were prepared by thermal evaporation to obtain a high-performance semi-transparent perovskite solar cell device.

[0092] Performance Testing

[0093] The perovskite layer was prepared from the CsPbI2Br precursor solution without adding DFBA and then the device was prepared as the control group. The device prepared in Example 1 was used as the experimental group for the following comparative analysis.

[0094] (1) The present invention introduces a molecular dipole additive DFBA, whose molecular structure and charge distribution are as follows Figure 1 As shown, Figure 1 A is the molecular structure of DFBA, Figure 1 B is the partial charge distribution diagram, based on Figure 1 It can be seen that the positive charge and negative charge are located on the amide group (-NH2) of the benzene ring side chain and the fluoride ion (-F) of the benzene ring, respectively, forming a unique molecular dipole moment;

[0095] (2) The present invention conducted X-ray diffraction analysis on the experimental group and the control group, and the results were as follows Figure 2 As shown, based on Figure 2 It can be seen that compared with the control group, the perovskite film in the experimental group has a stronger diffraction peak intensity and a narrower maximum half-maximum width (FWHM) value, indicating that the device prepared in the experimental group has stronger crystallinity;

[0096] (3) The present invention used scanning electron microscopy (SEM) to characterize the surface morphology of the control group and the experimental group. The SEM images are shown in Figure 2. Figure 3 As shown, based on Figure 3 It can be seen that both films are dense, with no pinholes in the SnO2 layer. However, the introduction of DFBA significantly increases the grain size of the film, from ≈450nm in the control group to ≈650nm in the experimental group. The larger grain size and smaller grain boundaries in the experimental group device can minimize carrier recombination, thereby improving device performance.

[0097] (4) The present invention further measured the experimental group and the control group using atomic force microscopy (AFM), and the results were as follows: Figure 4 As shown, based on Figure 4 A is the control group, Figure 4 B is the experimental group, based on Figure 4 It can be seen that the root mean square (RMS) roughness of the perovskite film decreased from 27.1nm in the control group to 18.5nm in the experimental group, which is conducive to the uniform deposition of ultra-thin metal electrodes; based on the above, it can be seen that DFBA regulates the crystallization kinetics, reduces the nucleation density, promotes grain growth, and ultimately significantly improves the film quality.

[0098] (5) The present invention conducted two-dimensional grazing incidence wide-angle X-ray scattering measurements on the experimental group and the control group, and the results are as follows Figure 5 As shown, Figure 5 A is the experimental group, Figure 5 B is the control group, based on Figure 5It can be seen that the diffraction pattern of the experimental group is similar to that of the control group, but shows stronger characteristic peaks, which confirms the preservation of the perovskite phase and no structural changes. It is worth noting that the diffraction peak of the (100) crystal plane of the experimental group shows higher intensity in the out-of-plane direction, indicating that the carrier mobility is enhanced and the defect density is reduced.

[0099] (6) The present invention conducted steady-state photoluminescence (PL) and two-dimensional PL mapping measurements on the experimental group and the control group, and the results are as follows: Figure 6 and Figure 7 As shown, Figure 6 A and Figure 6 B are the steady-state PL spectra of the experimental group and the control group on glass and SnO2 layer, Figure 7 Figures A and B are the two-dimensional PL mapping measurements of the experimental group and the control group on glass, respectively; Figure 6 As shown in A, steady-state PL spectra were collected from the top and bottom sides of the film to evaluate the effect of DFBA. For the control group on the bare glass, the PL intensity from the top side was significantly higher than that from the bottom side, indicating that the defect state was unevenly distributed between the top surface and the buried bottom interface.

[0100] based on Figure 6 As shown in Figure 2, the experimental film exhibited nearly identical PL intensities from both sides, indicating improved film uniformity. The PL intensities of the experimental films deposited on bare glass were 1.18 and 1.52 times those of the control film, respectively, indicating a higher radiative yield due to reduced non-radiative recombination. When deposited on SnO2, the experimental films exhibited significant fluorescence quenching, indicating enhanced charge extraction at the perovskite / SnO2 interface.

[0101] based on Figure 7 A and Figure 7 As shown in Figure 2, compared with the control group, the experimental group exhibited higher PL intensity and more uniform intensity distribution on bare glass, further confirming the good film quality of the improved perovskite layer.

[0102] (7) The present invention measured TRPL attenuation in the experimental group and the control group, and the results are as follows Figure 8 As shown, Figure 8 A and Figure 8 B are TRPL images of the experimental and control groups on the SnO2 layer and Spiro-OMeTAD, respectively. Figure 8It can be seen that when deposited on SnO2 film, the average carrier lifetime of the experimental group (7.21ns) is shorter than that of the control group (7.87ns), indicating that the efficiency of electron extraction from the perovskite to the SnO2 layer is higher. This result is consistent with the steady-state PL and two-dimensional PL mapping results. Similarly, when coated on the perovskite film with Spiro-OMeTAD, the average carrier lifetime of the experimental group is shorter than that of the control group, further confirming its enhanced hole transport ability.

[0103] Taken together, the PL and TRPL results jointly demonstrate that the DFBA additive effectively passivates defects in the perovskite film, thereby promoting efficient carrier extraction from both the electron and hole transport layers.

[0104] (8) The present invention uses ultraviolet visible spectroscopy (UV-Vis) and ultraviolet photoelectron spectroscopy (UPS) to analyze the energy levels of the control group and the experimental group. The results are as follows: Figure 9 As shown, Figure 9 A is the UPS spectra of the control group and the experimental group, Figure 9 B is the energy level diagram of the functional layer of the experimental group;

[0105] based on Figure 9 A: The optical band gaps of the control group and the experimental group were calculated to be 1.891eV and 1.882eV respectively using the Tauc equation applied to UV-Vis absorption spectroscopy. In addition, based on the UPS test results, the valence band maximum (E VB ), conduction band minimum (E CB ) and the Fermi level (E F ). The experimental group showed a well-matched energy level arrangement, E F The shift from -4.66eV (control group) to -4.38eV (experimental group) indicates that the perovskite surface has n-type semiconductor properties. This n-type surface, in contact with the p-type hole transport material Spiro-OMeTAD, improves the separation efficiency of photogenerated charge carriers.

[0106] based on Figure 9 As can be seen from B, the present invention selects two commercial tin oxide layers with different energy levels, α-SnO2 and β-SnO2, as the electron transfer layer (ETL) of ST-PSCs. The favorable energy level arrangement at the ITO / α-SnO2 / β-SnO2 / perovskite interface reduces the energy barrier, promotes the efficient transfer of electrons from perovskite to ITO, and minimizes interfacial recombination losses. This optimization helps significantly reduce the loss of open-circuit voltage.

[0107] (9) The present invention conducted Mott-Schottky tests on the experimental group and the control group, and the results were as follows: Figure 10As shown. The Mott-Schottky curve shows the V bi The value is 1.13 V, which is significantly higher than the control group’s 1.02 V. This indicates that the defect density of the experimental group is reduced and the band alignment is improved, thereby enhancing the driving force for charge extraction. Figure 11 is the Nyquist plot of the two groups of samples. The composite resistance of the control group (R rec ) is 858kΩ, while the R rec It was significantly increased to 1720kΩ, further verifying the reduction of interface defects and the improvement of charge transfer efficiency in the experimental group battery devices. Figure 12 Shows V OC In terms of the relationship with light intensity, the ideal factor of the experimental group was 1.128, while that of the control group was 1.837. This result confirms the significant role of DFBA in passivating defects and regulating energy levels.

[0108] (10) The present invention has carried out space charge limited current (SCLC) measurement on pure electron and pure hole devices, and the results are as follows Figure 13 As shown, the pure electronic device structure (ITO / α-SnO2 / β-SnO2 / perovskite / PCBM / MoO3 / Au) and the hole device structure (ITO / PTAA / perovskite / Spiro-OMeTAD / MoO3 / Au) are shown in Figure 2. Figure 13 A and 13B, based on Figure 13 It can be seen that the VTFL of the pure electron device decreased from 1.18V in the control group to 0.54V in the experimental group, and the VTFL of the pure hole device decreased from 1.22V in the control group to 0.58V in the experimental group. t ) from 9.66×10 15 cm -3 decreased to 4.42×10 in the experimental group 15 cm -3 , the defect density of pure hole devices (N t ) from 9.98×10 15 cm -3 decreased to 4.75×10 in the experimental group 15 cm -3 These results confirm that DFBA effectively reduces the defect density and suppresses non-radiative recombination, which is consistent with the previously observed enhanced PL intensity and prolonged carrier lifetime.

[0109] (11) The present invention uses first-principles (DFT) calculations to deeply study the interaction mechanism between DFBA molecules and perovskite at the atomic scale. After optimizing the perovskite structure using software, two different interaction mechanisms between DFBA and perovskite were designed: (i) F-Pb interaction and (ii) F-Pb and NHI / Br interaction. Figure 14 ). When only F – ions and Pb 2+ When the interaction occurs, the calculated adsorption energy (E ads ) is -0.3679eV. When NH…I / Br and F-Pb interact with each other, E ads The increase in adsorption energy to -0.8257 eV indicates that DFBA molecules and perovskite tend to form a synergistic passivation configuration.

[0110] (12) X-ray photoelectron spectroscopy (XPS) measurements further confirmed the interaction between DFBA and perovskite ( Figure 15 Compared to the F1s peak in pure DFBA, the F1s peak in the experimental perovskite corresponds to a lower binding energy (ΔE = 0.25 eV). Conversely, the Pb 4f and I 3d peaks in the experimental perovskite have higher binding energies than those in the control group (ΔE = 0.25 eV and 0.35 eV, respectively), providing strong evidence for multi-site interactions between NH…I / Br and F-Pb.

[0111] (13) The present invention conducted Fourier transform infrared (FTIR) spectroscopy analysis on pure DFBA and the perovskite of the experimental group, and the results were as follows: Figure 16 As shown, Figure 16 A and Figure 16 B are FTIR spectra of CF and NH stretching vibrations, based on Figure 16 It can be seen that pure DFBA is at 1333.75cm -1 The characteristic CF stretching vibration mode at 1332.25 cm-1 in the experimental perovskite -1 , confirming the interaction between DFBA and perovskite. In addition, the NH stretching peak from 3328.5 cm -1 (pure DFBA) moves to 3320.5 cm -1 (experimental group perovskite), further indicating the chemical interaction between DFBA and perovskite.

[0112] (14) In order to observe the in-plane strain distribution of the film surfaces in the experimental group and the control group, grazing incidence X-ray diffraction (GIXRD) measurements were performed at a fixed incident angle of 0.2°. The results are shown in Figure 1. Figure 17 As shown, Figure 17 A is the control group, Figure 17 B is the experimental group, Figure 17 C is sin 2 The linear fitting image of ψ-2θ is based on Figure 17 It can be seen that in the control group, with the increase of ψ value, the diffraction peak shifts significantly to lower angles, indicating lattice expansion and residual tensile stress. In contrast, the film in the experimental group has only a slight shift in the diffraction peak of the (200) crystal plane, indicating that Pb[I / Br]6 4- The octahedral distortion is very small. 2θ-sin of GIXRD spectra under different ψ values 2 The linear fitting of ψ further indicates that DFBA suppresses the octahedral distortion, leading to a significant reduction in defect density.

[0113] (15) The present invention prepared ST-PSCs with glass / ITO / α-SnO2 / β-SnO2 / CsPbI2Br / PMMA / Spiro-OMeT AD / MoO3 (5nm) / Au (8nm) structure. Figure 18 The performance parameters of ST-PSCs are shown in Figure 2. In addition, the structural diagram, JV curve and transmittance are shown in Figure 2. Figure 19 As shown, Figure 19 A is a schematic diagram of the semi-transparent battery structure. Figure 19 B is the JV curve of the semi-transparent battery. Figure 19 C is the visible light transmittance curve of the semi-transparent battery; based on Figure 19 It can be seen that the ultra-thin metal electrodes of 5nm MoO3 and 8nm Au are used as the top electrodes of the semi-transparent battery device. The MoO3 layer at the bottom promotes the layered growth of Au due to its high surface tension. The addition of DFBA significantly improves the performance of ST-PSCs, especially the V OC The photovoltaic performance of the experimental group's battery devices was significantly improved, with a PCE of 16.32%, corresponding to V OC is 1.377V, J SC 16.46 mA·cm -2 , the fill factor (FF) is 71.99%. Compared with the performance parameters of the control group battery device (PCE = 13.85%, V OC =1.247V, J SC =16.09mA·cm -2 , FF=69.05%), the performance of the experimental group has been significantly improved. In addition, to ensure the repeatability of the experimental results, we have statistically distributed the photovoltaic performance of the experimental group and the control group, such as Figure 20The enhanced photovoltaic performance is attributed to the DFBA-induced improvements in perovskite film crystallinity, defect passivation, interface contact, and energy-level alignment, which together promote efficient charge extraction and transport. High transparency (>60%) is exhibited in the visible light range (650-780 nm), reflecting the intrinsic high transmittance of CsPbI2Br. The AVT (380-780 nm) of the experimental and control groups is 31.69% and 32.54%, respectively. The slight decrease in AVT in the experimental group is due to enhanced crystallinity and increased light absorption. Considering the trade-off between AVT and PCE, LUE can be used as a key indicator for comprehensively evaluating the performance of ST-PSCs.

[0114] (16) The ST-PSCs of the present invention are compared with those of the prior art. Their AVT-PCE and AVT-LUE graphs are as follows: Figure 21 A and 21B show that the semitransparent solar cell devices of the experimental group achieved a record LUE of 5.17%, which demonstrates the potential of CsPbI2Br perovskite films for high-performance ST-PSCs and proves the effectiveness of DFBA in balancing PCE and AVT.

[0115] (17) The stability of ST-PSCs was evaluated at room temperature and high temperature (85 °C) in a nitrogen atmosphere, and the results are shown in Figure 2. Figure 22 As shown, Figure 22 A is room temperature, Figure 22 B is under high temperature conditions, based on Figure 22 It can be seen that the device in the experimental group maintained 94% of its initial PCE at 25°C and 85°C, and maintained 88% of its initial PCE after 600 hours, which is significantly better than that of the control group. This improvement in stability is due to the suppression of non-radiative recombination of carriers and segregation of halide ions, further demonstrating the feasibility of DFBA-improved ST-PSCs in practical applications.

[0116] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the field should understand that the specific implementation methods of the present invention can still be modified or replaced by equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be covered by the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a high-performance semi-transparent perovskite solar cell device, characterized in that: The following steps are involved: Lead bromide, cesium iodide, lead iodide, methylamine hydrochloride and 3,5-difluoroaniline hydrochloride are dissolved in a specific solvent to obtain a perovskite precursor solution; dissolving polymethyl methacrylate in isopropyl alcohol to obtain a polymethyl methacrylate solution; Dissolving 2,2',7,7'-tetrakis[n,n-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene, a lithium bis(trifluoromethanesulfonyl)imide solution, and 4-tert-butylpyridine in chlorobenzene to obtain a 2,2',7,7'-tetrakis[n,n-bis(4-methoxyphenyl)amino]-9,9'-spirobifluorene solution; Ultrasonic treatment is performed on an ITO-coated glass substrate, and then α-SnO2 and β-SnO2 colloidal solutions are sequentially coated on the ITO-coated glass substrate to obtain a pretreated ITO-coated glass substrate; performing a first annealing treatment on the pretreated ITO-coated glass substrate, and then coating the perovskite precursor solution on the pretreated ITO-coated glass substrate to obtain a wet film; The wet film is subjected to a second annealing treatment, and then coated with the polymethyl methacrylate solution and 2,2',7,7'-tetrakis[n,n-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene solution, and finally MoO3 and Au electrodes are prepared by thermal evaporation to obtain the high-performance semi-transparent perovskite solar cell device.

2. The method for preparing a high-performance semi-transparent perovskite solar cell device according to claim 1, characterized in that: The mass ratio of the lead bromide, cesium iodide, lead iodide, methylamine hydrochloride and 3,5-difluoroaniline hydrochloride is (150-300): (20-60): (600-800): (1-7): (5-10).

3. The method for preparing a high-performance semi-transparent perovskite solar cell device according to claim 1, wherein: The concentration of the perovskite precursor solution is 0.1-1 M, and the specific solvent is one or more of DMF, DMSO or NMP.

4. The method for preparing a high-performance semi-transparent perovskite solar cell device according to claim 1, characterized in that: The concentration of the polymethyl methacrylate solution is 0.1-1 mg / mL, and the volume ratio of the lithium bis(trifluoromethanesulfonyl)imide solution to 4-tert-butylpyridine is (20-60):(10-40).

5. The method for preparing a high-performance semi-transparent perovskite solar cell device according to claim 1, characterized in that: The ultrasonic treatment specifically comprises: ultrasonic treatment in acetone, deionized water and ethanol for 5 to 30 minutes respectively.

6. The method for preparing a high-performance semi-transparent perovskite solar cell device according to claim 1, characterized in that: The coating method is spin coating, the speed is 4000 rpm / min, and the time is 25 to 50 seconds.

7. The method for preparing a high-performance semi-transparent perovskite solar cell device according to claim 1, characterized in that: In the coating process, one of ethyl acetate, chlorobenzene, isopropyl alcohol, ether or toluene is used as an anti-solvent.

8. The method for preparing a high-performance semi-transparent perovskite solar cell device according to claim 1, characterized in that: The first annealing treatment is performed at a temperature of 120-180° C. and for a time of 20-40 minutes; the second annealing treatment is performed in a nitrogen-filled environment at a temperature of 120-180° C. and for a time of 10-40 minutes.

9. The method for preparing a high-performance semi-transparent perovskite solar cell device according to claim 1, characterized in that: The 3,5-difluoroaniline hydrochloride contains one or more functional groups such as -F, -Cl, -NH2, -COOH, -OH, -C=O, -CHO, and -NO2.

10. A high-performance semi-transparent perovskite solar cell device prepared by the method for preparing a high-performance semi-transparent perovskite solar cell device according to any one of claims 1 to 9.

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