Modified nickel oxide thin film, passivated perovskite solar cell and preparation method
Patent Information
- Application Number
- CN202611208334.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-08-11
- Publication Date
- 2026-09-25
AI Technical Summary
然而，现有技术对于掺杂元素原料选择都是以改善电荷转移和提取为主，使得到的改性NiOx薄膜难以有效钝化NiOx与钙钛矿层界面处的缺陷，从而出现泄漏电流和非辐射复合的问题，引发光电器件的性能和稳定性
本发明利用MgF2进行掺杂形成的改性NiOx薄膜，掺入的Mg2+促进了Ni3+物种的形成和稳定，未经改性的氧化镍薄膜Ni3+/Ni2+的比例为2.98，经氟化镁掺杂后的改性薄膜Ni3+/Ni2+的比例为3.79，增强了p型导电性，改善的空穴传输能力和更有利的空穴传输层的能级排列。同时，F离子稳定了钙钛矿界面，显著降低了非辐射复合损失，促进了高质量钙钛矿薄膜的形成；此外，氟化镁还成功抑制了Ni3+与钙钛矿之间的氧化还原反应。
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Figure CN122825641A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of thin film material preparation technology, specifically relating to a modified nickel oxide thin film, a passivated perovskite solar cell, and a method for preparing the same. Background Technology
[0002] NiO x NiO is an inorganic p-type semiconductor that is commonly used as a hole transport layer in inverted and tandem perovskite solar cells due to its cost-effectiveness, stability, and scalability. However, there is still room for improvement. x The presence of surface oxygen vacancies and uncoordinated metal ion defects contributes to this enhancement potential. Furthermore, submicron-scale defects exist on the lower surface of the perovskite material. NiO x The interaction between the perovskite film and the perovskite film can also lead to interfacial reactions, resulting in nonradiative recombination at the interface.
[0003] Existing techniques typically use Li, Co, Cu, Cs, and Ag as target elements for doping modification in NiO. x Modification can be achieved in thin films. For example, W. Chen, Y. Wu, J. Fan, AB Djurišić, F. Liu, HW Tam, A. Ng, C. Surya, WK Chan, D. Wang, ZB He, Advanced Energy Materials 2018, 8. They disclosed the doping of NiO with Cu as the target doping element. x The obtained NiO x The thin film conductivity and carrier mobility are improved, and NiO x The thin film exhibits a larger work function, which, along with increased conductivity, enables improved charge transfer and extraction. However, current techniques for selecting dopant elements primarily focus on improving charge transfer and extraction, resulting in modified NiO. x Thin films are difficult to effectively passivate NiO x Defects at the interface with the perovskite layer can lead to leakage current and non-radiative recombination issues, affecting the performance and stability of optoelectronic devices. Summary of the Invention
[0004] To address the aforementioned problems, this invention provides a modified nickel oxide thin film, a passivated perovskite solar cell, and a method for preparing the same.
[0005] The first aspect of this invention provides a modified NiO x Thin film, in NiO x The thin film is doped with MgF2; the modified NiO xIn the thin film, the mass percentage of MgF2 is 0.037%~0.373%. NiO x In this context, x represents the ratio of the number of oxygen atoms to the number of nickel atoms.
[0006] This invention utilizes modified NiO formed by mixing magnesium fluoride and nickel oxide. x As a hole transport layer, the Mg and F ions in magnesium fluoride effectively passivate NiO. x Surface defects, optimized Ni 3+ / Ni 2+ The ratio of nitrogen ions improved hole extraction capability and bandgap matching. Simultaneously, F ions stabilized the perovskite interface, significantly reduced nonradiative recombination losses, and promoted the formation of high-quality perovskite films. Furthermore, magnesium fluoride successfully suppressed Ni... 3+ The redox reaction between perovskite and nitrogen oxides. This invention selects magnesium fluoride as the dopant; Mg ions improve charge transfer and extraction, while F ions effectively passivate NiO. x Defects at the interface with the perovskite layer enable a doped material to achieve a dual effect, effectively solving the problem of the difficulty in effectively passivating NiO using existing technologies. x The problem of defects at the interface with the perovskite layer.
[0007] In another preferred embodiment, the modified NiO x The thickness of the layer is 150nm~200nm.
[0008] A second aspect of this invention provides a perovskite solar cell, wherein the perovskite solar cell comprises, from bottom to top, a conductive substrate, and the modified NiO. x Thin film, self-assembled monolayer, perovskite light-absorbing layer, perovskite passivation layer, electron transport layer, electron blocking layer and metal electrode.
[0009] A third aspect of this invention provides a method for preparing the perovskite solar cell, comprising the following steps: MgF2 and NiO x When mixed in a solvent, modified NiO is obtained. x Solution; modified NiO x The solution was spin-coated onto a conductive substrate, and after annealing, modified NiO was obtained. x Thin film; using MgF2 and NiO x Mixed in a solvent to modify NiO x Modified NiO was obtained by spin-coating deposition of solution. xThe thin film improves hole extraction capability, film conductivity and film transmittance, improves energy level matching, reduces film surface roughness, and provides more binding sites for the deposition of the upper SAM layer, resulting in higher SAM layer coverage. After annealing, MgF2 can enter the perovskite layer, stabilize the perovskite interface, significantly reduce non-radiative recombination loss, and promote the formation of high-quality perovskite thin films.
[0010] In modified NiO x A self-assembled monolayer, a perovskite light-absorbing layer, a perovskite passivation layer, an electron transport layer, and an electron blocking layer are sequentially spin-coated onto the thin film. A perovskite solar cell is obtained by vacuum deposition of a metal electrode on an electron blocking layer.
[0011] In another preferred embodiment, the annealing treatment is performed at a temperature of 120°C to 125°C for a time of 15 min to 16 min.
[0012] In another preferred embodiment, the solvent is water.
[0013] In another preferred embodiment, the conductive substrate is ITO with a sheet resistance ≤15 ohms and a transmittance ≥92%.
[0014] In another preferred embodiment, the perovskite light-absorbing layer is made of Cs 0.05 MA 0.1 FA 0.85 PbI3 was obtained by spin-coating deposition of a perovskite precursor solution.
[0015] The specific preparation method of the perovskite precursor solution is as follows: According to the chemical formula of the perovskite precursor, methylammonium chloride, cesium iodide, methylammonium iodide, formamidinium hydroiodate and lead iodide are mixed in a solvent system to obtain a perovskite precursor solution.
[0016] The solvent is a mixture of N,N-dimethylformamide and dimethyl sulfoxide, with a volume ratio of 4:1.
[0017] In another preferred embodiment, the self-assembled monolayer is Me-4PACz; the electron transport layer is PC. 61 BM; the electron blocking layer is BCP; the metal electrode is an Ag electrode.
[0018] Compared with the prior art, the present invention has the following technical effects: This invention utilizes MgF2 to form modified NiO x Thin film, doped with Mg 2+ Promoted Ni 3+Speciation and stabilization of unmodified nickel oxide thin films Ni 3+ / Ni 2+ The proportion is 2.98, and the modified Ni film after magnesium fluoride doping is... 3+ / Ni 2+ The ratio of 3.79 enhances p-type conductivity, improves hole transport capability, and provides a more favorable energy level arrangement for the hole transport layer. Simultaneously, F ions stabilize the perovskite interface, significantly reduce non-radiative recombination losses, and promote the formation of high-quality perovskite films; furthermore, magnesium fluoride successfully suppresses Ni... 3+ Redox reactions with perovskite.
[0019] Using the modified NiO of this invention x As a hole transport layer, the thin film, during thermal annealing, F - Gradually migrate towards the buried perovskite / HTL interface and interact with uncoordinated Pb. 2+ Ion coordination regulates crystallization and passivates interface defects, significantly reducing non-radiative recombination losses and promoting the formation of high-quality perovskite films.
[0020] This invention utilizes NiO x Introducing MgF2 into the precursor for NiO x Interface modification of MgF2-modified perovskite solar cells passivates surface defects in the thin film, reduces non-radiative recombination, improves interface energy level matching, and enhances conductivity, thereby improving the voltage, fill factor, and stability of the optoelectronic device. The MgF2-modified device achieved a photoelectric conversion efficiency of 26%. In stability tests, it exhibited excellent long-term stability. Furthermore, the process is simple, easily reproducible, and low-cost. Attached Figure Description
[0021] Figure 1 NiO in Comparative Example 1 x Scanning electron microscope image of the thin film.
[0022] Figure 2 The modified NiO in Example 1 x Scanning electron microscope image of the thin film.
[0023] Figure 3 This is a scanning electron microscope image of the bottom of the perovskite light-absorbing layer in Comparative Example 1.
[0024] Figure 4 This is a scanning electron microscope image of the bottom of the perovskite light-absorbing layer in Example 1.
[0025] Figure 5 This is a scanning electron microscope image of the top of the perovskite light-absorbing layer in Comparative Example 1.
[0026] Figure 6This is a scanning electron microscope image of the top of the perovskite light-absorbing layer in Example 1.
[0027] Figure 7 The JV curve is shown for the perovskite solar cell prepared in Comparative Example 1.
[0028] Figure 8 The image shows the JV curve of the perovskite solar cell prepared in Example 1.
[0029] Figure 9 The figure shows the JV curve of the perovskite solar cell prepared in Example 2; in the figure, 0.1mM, 0.3mM, 0.5mM and 0.75mM represent different amounts of MgCl2 replacing MgF2 in step 2.
[0030] Figure 10 The figure shows the JV curve of the perovskite solar cell prepared in Example 3; in the figure, 0.1mM, 0.3mM, 0.5mM and 0.75mM represent different amounts of PbF2 replacing MgF2 in step 2.
[0031] Figure 11 The JV curves are for the perovskite solar cells prepared in Examples 4 to 7. Detailed Implementation
[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.
[0033] Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0034] The ITO conductive glass used in the following examples has a size of 14.9mm × 14.9mm, a sheet resistance of ≤15 ohms, a film thickness of 125nm, and a transmittance of ≥92%.
[0035] Me-4PACz purchased from TCI, PC 61 BM was purchased from Xi'an Yulu Solar Energy, and BCP was purchased from TCI.
[0036] Example 1 A modified NiO x Thin film, NiO through MgF2 x The modified NiO was obtained by mixing. x Thin film; MgF2 doping amount is 0.5 mM.
[0037] Using the above-mentioned modified NiO xA method for fabricating perovskite solar cells using thin-film technology includes the following steps: Step 1, Substrate Pretreatment: Immerse the ITO conductive glass in water containing detergent for 10 minutes and rub the conductive surface repeatedly 20 times to remove surface dust. Then, ultrasonically clean it for 15 minutes each with deionized water, isopropanol, and anhydrous ethanol. Finally, soak it in anhydrous ethanol for later use.
[0038] The cleaned ITO conductive glass was placed in an ultraviolet ozone cleaner for 10 minutes to remove organic contaminants from the surface, resulting in pretreated ITO conductive glass.
[0039] Step 2: Preparation of modified NiO x film: 20mg NiO x 0.5 mM MgF2 was dissolved in 1 mL of deionized water, sonicated in an ice bath for 10 min, and then filtered through a 0.22 aqueous filter to obtain modified NiO. x Solution.
[0040] Using pretreated ITO conductive glass as a substrate, 80 µL of modified NiO was pipetted in. x The solution was dropped onto the substrate for spin-coating deposition. The spin-coating speed was controlled at 2000 rpm / s, and the spin-coating time was 30 s. After spin-coating, the substrate was placed on a heating stage at 120℃ and annealed for 15 min to obtain a modified NiO with a thickness of 30 nm. x Thin film; wherein, modified NiO x The mass percentage of MgF2 in the film is 0.187%.
[0041] Step 3: Preparation of SAM thin film: Dissolve 0.5 mg of Me-4PACz in 1 mL of anhydrous ethanol and stir at 800 rpm / min for 2 h to obtain a SAM solution.
[0042] In a glove box with humidity <0.01 ppm, modified NiO was used. x Using a thin film as a substrate, 70 µL of SAM solution was pipetted onto the modified NiO film. x Spin-coating deposition was performed on the thin film, with the spin-coating speed controlled at 3000 rpm / s and the spin-coating time at 30 s. After spin-coating was completed, the film was placed on a heating stage at 100 ℃ and annealed for 10 min to obtain a SAM thin film with a thickness of 5 nm.
[0043] Step 4: Prepare the perovskite light-absorbing layer: 16.67 mg of methylammonium chloride, 21.56 mg of cesium iodide, 26.55 mg of methylammonium iodide, 243.68 mg of formamidinium hydroiodate and 807.24 mg of lead iodide were dissolved in 800 μL of N,N-dimethylformamide and 200 μL of dimethyl sulfoxide. The solution was stirred at 800 rpm / min for 2 h at room temperature to obtain a perovskite precursor solution.
[0044] In a glove box with humidity <0.01 ppm, using a SAM film as a substrate, 50 µL of perovskite precursor solution was pipetted onto the SAM film for spin coating deposition. The low speed of the spin coater was 1000 rpm and the spin coating time was 10 s. The high speed of the spin coater was 5000 rpm and the spin coating time was 30 s. 150 µL of chlorobenzene was added 15 s before the end of the spin coating. After the spin coating was completed, the film was placed on a heating stage at 120 °C and annealed for 10 min to obtain a perovskite light-absorbing layer with a thickness of 500 nm.
[0045] Step 5: Prepare the perovskite passivation layer: Dissolve 0.5 mg of EDADI and 0.1 mg of PEAI in 1 mL of isopropanol and stir at 800 rpm / min for 2 h to obtain a perovskite passivation layer solution.
[0046] Using a perovskite light-absorbing layer as a substrate, 40 µL of perovskite passivation layer solution was pipetted onto the perovskite light-absorbing layer for spin-coating deposition. The spin-coating speed was controlled at 3000 rpm / s and the spin-coating time was 30 s. After spin-coating was completed, a perovskite passivation layer with a thickness of 5 nm was obtained.
[0047] Step 6: Fabrication of the electron transport layer: 20mg of PC 61 BM was dissolved in 1 mL of chlorobenzene and stirred at 800 rpm for 2 h to obtain PC. 61 BM solution.
[0048] Using a perovskite passivation layer as a substrate, 40 µL of PC was aspirated using a pipette. 61 BM solution was dropped onto the perovskite passivation layer for spin coating deposition. The spin coating speed was controlled at 3000 rpm / s and the spin coating time was 30s. After spin coating was completed, the layer was placed on a heating stage at 70℃ for annealing for 10min to obtain an electron transport layer with a thickness of 35nm.
[0049] Step 7: Prepare the electron blocking layer: Dissolve 0.5 mg of BCP in 1 mL of isopropanol and stir at 800 rpm / min for 2 h to obtain a BCP solution.
[0050] Using the electron transport layer as a substrate, 60 µL of BCP solution was pipetted onto the electron transport layer for spin coating deposition. The spin coating speed was controlled at 6000 rpm / s and the spin coating time was 30 s. After spin coating, the layer was placed on a heating stage at 70 °C for annealing for 10 min to obtain an electron blocking layer with a thickness of 8 nm.
[0051] Step 8: Fabrication of perovskite solar cells: A perovskite solar cell was obtained by evaporating an Ag electrode onto an electron blocking layer using a vacuum deposition machine. The Ag electrode thickness was 100 nm. The specific parameters for the evaporation were as follows:
[0052] The evaporation rate for the first 20 nm is 0.5 Å / S, the evaporation rate for 20 nm to 50 nm is 1.0 Å / S, and the evaporation rate for 50 nm to 100 nm is 1.5 Å / S.
[0053] Example 2 A method for preparing a perovskite solar cell includes the following steps: The difference from Example 1 is that MgCl2 is used instead of MgF2, and the remaining steps are the same as in Example 1.
[0054] Example 3 A method for preparing a perovskite solar cell includes the following steps: The difference from Example 1 is that PbF2 is used instead of MgF2, and the remaining steps are the same as in Example 1.
[0055] Example 4 A method for preparing a perovskite solar cell includes the following steps: The difference from Example 1 is that the MgF2 doping amount is 0.1 mM; all other steps are the same as in Example 1, to prepare modified NiO. x The film contains 0.037% MgF2 by mass.
[0056] Example 5 A method for preparing a perovskite solar cell includes the following steps: The difference from Example 1 is that the MgF2 doping amount is 0.3 mM; all other steps are the same as in Example 1, to prepare modified NiO. x The film contains 0.112% MgF2 by mass.
[0057] Example 6 A method for preparing a perovskite solar cell includes the following steps: The difference from Example 1 is that the MgF2 doping amount is 0.75 mM; all other steps are the same as in Example 1, resulting in the preparation of modified NiO. x The film contains 0.280% MgF2 by mass.
[0058] Example 7 A method for fabricating a perovskite solar cell includes the following steps: The difference from Example 1 is: Modified NiO was prepared by using MgF2 doping at a concentration of 1.0 mM and following the same steps as in Example 1. x The film contains 0.373% MgF2 by mass.
[0059] Comparative Example 1 A method for fabricating a perovskite solar cell includes the following steps: Step 1, Substrate Pretreatment: Immerse the ITO conductive glass in water containing detergent for 10 minutes and rub the conductive surface repeatedly 20 times to remove surface dust. Then, ultrasonically clean it for 15 minutes each with deionized water, isopropanol, and anhydrous ethanol. Finally, soak it in anhydrous ethanol for later use.
[0060] The cleaned ITO conductive glass was placed in an ultraviolet ozone cleaner for 10 minutes to remove organic contaminants from the surface, resulting in pretreated ITO conductive glass.
[0061] Step 2: Preparation of NiO x film: 20mg NiO x Dissolved in 1 mL of deionized water, sonicated in an ice bath for 10 min, and then filtered through a 0.22mm aqueous filter to obtain NiO. x Solution.
[0062] Using pretreated ITO conductive glass as a substrate, 80 µL of NiO was pipetted in. x The solution was dropped onto the substrate for spin-coating deposition. The spin-coating speed was controlled at 2000 rpm / s, and the spin-coating time was 30 s. After spin-coating, the substrate was placed on a heating stage at 120℃ for annealing for 15 min to obtain NiO. x film.
[0063] Step 3: Preparation of SAM thin film: Dissolve 0.5 mg of Me-4PACz in 1 mL of anhydrous ethanol and stir at 800 rpm / min for 2 h to obtain a SAM solution.
[0064] In a glove box with humidity <0.01 ppm, using NiO x Using a thin film as a substrate, 70 µL of SAM solution was pipetted onto NiO. x Spin-coating deposition was performed on the thin film, with the spin-coating speed controlled at 3000 rpm / s and the spin-coating time at 30 s. After spin-coating was completed, the film was placed on a heating stage at 100 ℃ and annealed for 10 min to obtain the SAM thin film.
[0065] Step 4: Prepare the perovskite light-absorbing layer: 16.67 mg of methylammonium chloride, 21.56 mg of cesium iodide, 26.55 mg of methylammonium iodide, 243.68 mg of formamidinium hydroiodate and 807.24 mg of lead iodide were dissolved in 800 μL of N,N-dimethylformamide and 200 μL of dimethyl sulfoxide. The solution was stirred at 800 rpm / min for 2 h at room temperature to obtain a perovskite precursor solution.
[0066] In a glove box with humidity <0.01 ppm, using a SAM film as a substrate, 50 µL of perovskite precursor solution was pipetted onto the SAM film for spin coating deposition. The low speed of the spin coater was 1000 rpm and the spin coating time was 10 s. The high speed of the spin coater was 5000 rpm and the spin coating time was 30 s. 150 µL of chlorobenzene was added 15 s before the end of the spin coating. After the spin coating was completed, the film was placed on a heating stage at 120 °C and annealed for 10 min to obtain the perovskite light-absorbing layer.
[0067] Step 5: Prepare the perovskite passivation layer: Dissolve 0.5 mg of EDADI and 0.1 mg of PEAI in 1 mL of isopropanol and stir at 800 rpm / min for 2 h to obtain a perovskite passivation layer solution.
[0068] Using the perovskite light-absorbing layer as a substrate, 40 µL of perovskite passivation layer solution was pipetted onto the perovskite light-absorbing layer for spin coating deposition. The spin coating speed was controlled at 3000 rpm / s and the spin coating time was 30 s. After spin coating was completed, the perovskite passivation layer was obtained.
[0069] Step 6: Fabrication of the electron transport layer: 20mg of PC 61 BM was dissolved in 1 mL of chlorobenzene and stirred at 800 rpm for 2 h to obtain PC. 61 BM solution.
[0070] Using a perovskite passivation layer as a substrate, 40 µL of PC was aspirated using a pipette. 61 BM solution was dropped onto the perovskite passivation layer for spin coating deposition. The spin coating speed was controlled at 3000 rpm / s and the spin coating time was 30 s. After spin coating was completed, the layer was placed on a heating stage at 70 ℃ for annealing for 10 min to obtain the electron transport layer.
[0071] Step 7: Prepare the electron blocking layer: Dissolve 0.5 mg of BCP in 1 mL of isopropanol and stir at 800 rpm / min for 2 h to obtain a BCP solution.
[0072] Using the electron transport layer as a substrate, 60 µL of BCP solution was pipetted onto the electron transport layer for spin coating deposition. The spin coating speed was controlled at 6000 rpm / s and the spin coating time was 30 s. After spin coating, the layer was placed on a heating stage at 70 °C for annealing for 10 min to obtain the electron blocking layer.
[0073] Step 8: Fabrication of perovskite solar cells: A perovskite solar cell was obtained by evaporating an Ag electrode onto an electron blocking layer using a vacuum deposition machine. The Ag electrode was 100 nm thick.
[0074] The perovskite solar cells obtained in Examples 1 to 7 and Comparative Example 1 were experimentally tested as follows.
[0075] 1. SEM characterization.
[0076] like Figure 1 As shown, NiO is deposited on an ITO conductive glass substrate. x The film exhibits significant agglomeration and noticeable protrusions. If in NiO... x If a perovskite light-absorbing layer is deposited on the thin film, the ITO thin film on the substrate will come into contact with the perovskite light-absorbing layer, which will seriously affect the extraction of charge carriers.
[0077] like Figure 2 As shown, modified NiO is deposited on an ITO conductive glass substrate. x After film formation, magnesium fluoride was used to treat NiO. x The thin film was modified to obtain modified NiO. x Thin film. Compared to NiO in Comparative Example 1. x Thin film, magnesium fluoride for NiO x Modified NiO formed after thin film modification treatment x The film agglomeration was significantly reduced, with no obvious protrusions. A perovskite light-absorbing layer uniformly covered the modified NiO. x On the thin film, a uniform hole transport layer will effectively transport holes and block electrons.
[0078] like Figures 3-4 As shown, the bottom surface of the perovskite was peeled off using ultraviolet (UV) adhesive to observe its morphology, in Comparative Example 1, NiO x The perovskite substrate grown on the thin film has many tiny pore defects at the grain boundaries and the crystal size is small; while the modified NiO in Example 1 x The grain boundary regions on the perovskite substrate grown on the thin film are denser and larger in size.
[0079] like Figures 5-6 As shown, observing the top of the perovskite film, in Comparative Example 1, NiO...x The perovskite crystals grown on the thin film are smaller in size; while the modified NiO in Example 1... x The increased size of the perovskite grown on the thin film is due to the modified NiO in Example 1. x The thin film is smoother and more even, which allows for more ordered growth of the perovskite crystals. Larger perovskite crystals facilitate carrier transport and reduce recombination.
[0080] 2. Electrical performance testing.
[0081] AM 1.5G (100mW cm) from Elitetech solar simulator -2 The JV curve of the PSC was recorded under solar illumination, and the corresponding scan rate for this curve was 0.02V / s. -1 .
[0082] like Figures 7-8 As shown in Table 1, compared with the perovskite solar cell prepared in Comparative Example 1, the perovskite solar cell prepared in Example 1 showed improvements in both Voc and FF to varying degrees, thus exhibiting a higher PCE; this is due to the modified NiO in Example 1. x The thin film exhibits higher quality and stronger hole extraction capability in modified NiO. x The perovskite film deposited on top of the thin film has stronger light absorption capabilities, generating more charge carriers and thus improving photocurrent. When the scanning direction is changed, the perovskite solar cell device prepared in Comparative Example 1 exhibits a significant difference in its JV curve, i.e., a hysteresis effect. This may be because the poor quality of the HTL and perovskite film hinders carrier extraction and transport, resulting in more charge accumulation at the interface between the hole transport layer and the perovskite layer. In contrast, the perovskite solar cell device prepared in Example 1 exhibits less hysteresis due to the larger crystal size and better crystallinity of the perovskite.
[0083] like Figures 9-10 As shown in Table 1, compared with the perovskite solar cell prepared in Comparative Example 1, the Voc and FF of the perovskite solar cells prepared in Examples 2 and 3 are increased to varying degrees, thus exhibiting higher PCE, proving that simple doping can improve the performance of nickel oxide thin films.
[0084] like Figure 11 As shown in Table 1, when the magnesium fluoride doping amount reaches 0.5 mM, the Voc and FF of the prepared perovskite solar cells are improved to varying degrees, thus exhibiting higher PCE.
[0085] Table 1. Electrical performance data of perovskite solar cells prepared in Examples 1-7 and Comparative Example 1. The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.
Claims
1. A modified NiO for passivating perovskite solar cells x The thin film is characterized by being In NiO x The thin film is doped with MgF2; the modified NiO x The mass percentage of MgF2 in the thin film is 0.037%~0.373%.
2. The modified NiO for passivating perovskite solar cells according to claim 1 x The thin film is characterized by, The modified NiO x The thickness of the layer is 150nm~200nm.
3. A perovskite solar cell, characterized in that, The perovskite solar cell consists of, from bottom to top, a conductive substrate, and the modified NiO as described in claim 2. x Thin film, self-assembled monolayer, perovskite light-absorbing layer, perovskite passivation layer, electron transport layer, electron blocking layer and metal electrode.
4. A method for preparing a perovskite solar cell according to claim 3, characterized in that, Includes the following steps: MgF2 and NiO x When mixed in a solvent, modified NiO is obtained. x Solution; modified NiO x The solution was spin-coated onto a conductive substrate, and after annealing, modified NiO was obtained. x film; In modified NiO x A self-assembled monolayer, a perovskite light-absorbing layer, a perovskite passivation layer, an electron transport layer, and an electron blocking layer are sequentially spin-coated onto the thin film. A perovskite solar cell is obtained by vacuum deposition of a metal electrode on an electron blocking layer.
5. The method for preparing a perovskite solar cell according to claim 4, characterized in that, The annealing process is performed at a temperature of 120℃~125℃ for 15min~16min.
6. The method for preparing a perovskite solar cell according to claim 4, characterized in that, The solvent is water.
7. The method for preparing a perovskite solar cell according to claim 4, characterized in that, The conductive substrate is ITO with a sheet resistance ≤15 ohms and a transmittance ≥92%.
8. The method for preparing a perovskite solar cell according to claim 4, characterized in that, The perovskite light-absorbing layer is made of Cs 0.05 MA 0.1 FA 0.85 PbI3 was obtained by spin-coating deposition of a perovskite precursor solution.
9. The method for preparing a perovskite solar cell according to claim 4, characterized in that, The self-assembled monolayer is Me-4PACz; the electron transport layer is PC. 61 BM; the electron blocking layer is BCP; the metal electrode is an Ag electrode.