Method for preparing all-inorganic perovskite battery by taking pentafluorobenzoic acid and 1, 4-butanediamine as synergistic passivator
By using pentafluorobenzoic acid and 1,4-butanediamine as synergistic passivators to improve the energy level of the active layer, the problem of large energy loss in all-inorganic perovskite batteries was solved, and the battery performance and stability were improved.
Patent Information
- Application Number
- CN202511648360.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-12
- Publication Date
- 2026-01-13
AI Technical Summary
In the existing technology, all-inorganic perovskite solar cells suffer from large energy losses during electron transport, and 1,4-butanediamine (BDA) has weak anchoring ability as a passivating agent, resulting in a single passivation effect and limited energy level improvement capability.
Using pentafluorobenzoic acid and 1,4-butanediamine as synergistic passivators, a one-step method was used to p-type dope the surface of perovskite solar cells. The synergistic passivation improved the energy level of the active layer and regulated the crystallization of perovskite, thus preparing an all-inorganic perovskite solar cell.
It effectively reduced the energy level barrier between the perovskite and the electron transport layer, improved the electron transport efficiency, and enhanced the photoelectric conversion efficiency and stability of the perovskite solar cell, increasing the photoelectric conversion efficiency from 18.57% to 20.71%.
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Figure CN121335397A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The application relates to the technical field of perovskite batteries, in particular to a method for preparing a full-inorganic perovskite battery by using pentafluorobenzoic acid and 1,4-butanediamine as a synergistic passivation agent. BACKGROUND
[0002] Perovskite solar cells (PSCs) have shown great potential in the next generation of photovoltaics. In recent years, the power conversion efficiency (PCE) of single-junction inorganic-organic hybrid perovskite solar cells has been improved to about 27%, which is comparable to commercial silicon-based solar cells. However, the high volatility of organic cations may lead to poor photothermal stability of perovskite materials. Therefore, replacing the organic cations at the A site of perovskite with cesium ions (Cs + ) can obtain a full-inorganic CsPbX3 perovskite system with more excellent photothermal stability. Although the development of inverted structure CsPbI3 solar cells is later than that of the normal structure system, it has more abundant optimization paths and methods. At the same time, the inverted structure cesium-based inorganic perovskite solar cell is expected to become the core battery type for developing stacked solar cells due to its ideal band gap energy.
[0003] Although CsPbI3 perovskite solar cells have great potential, the mismatch between the energy level and the ETL layer leads to a huge energy loss in the transmission process of electrons, which greatly limits the development of full-inorganic perovskite batteries. The use of 1,4-butanediamine (BDA) greatly improves the efficiency of full-inorganic perovskite batteries [Fu, S.; Le, J.; Guo, X.; Sun, N.; Zhang, W.; Song, W.; Fang, J. Polishing the Lead-Poor Surface for Efficient Inverted CsPbI3 Perovskite Solar Cells. Adv. Mater. 2022, 34, e2205066], but BDA has weak anchoring ability due to the chemical inertness of the active layer, and the passivation effect is single and the energy level improvement ability is not strong [Synergistic Passivation for Efficient Inverted Inorganic Perovskite Solar Cells.” Adv. Energy Mater. 15, no. 36 (2025): 15, e03133. ].
[0004] The present application aims to improve the energy level of the active layer by synergistic passivation and passivate the active layer to improve the efficiency of perovskite solar cells, and proposes a method for preparing all-inorganic perovskite solar cells by using pentafluorobenzoic acid and 1,4-butanediamine as synergistic passivation agents. SUMMARY
[0005] The present application provides a method for preparing all-inorganic perovskite solar cells by using pentafluorobenzoic acid and 1,4-butanediamine as synergistic passivation agents, which uses the strategy of synergistic passivation to improve the energy level and surface passivation of the active layer to improve the efficiency of the solar cell.
[0006] The technical scheme adopted by the present application is:
[0007] A method for preparing all-inorganic perovskite solar cells by using pentafluorobenzoic acid and 1,4-butanediamine as synergistic passivation agents, comprising the following steps in sequence:
[0008] Step a: plasma cleaning the ITO surface to improve the hydrophilicity of the ITO surface;
[0009] Step b: spin coating P3CT-N dissolved in methanol on the ITO surface and performing annealing treatment to prepare a hole transport layer (HTL);
[0010] Step c: spin coating (2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl) phosphonic acid (MeO-2PACz) dissolved in isopropyl alcohol on the hole transport layer, and then performing annealing treatment to prepare a self-assembled monolayer (SAM);
[0011] Step d: spin coating perovskite precursor solution obtained by dissolving dimethylammonium lead iodide (DMAPbI3), lead iodide (PbI2), and cesium iodide (CsI) in DMF / DMSO on the self-assembled monolayer (SAM), and then performing annealing treatment to prepare a perovskite layer;
[0012] Step e: mixing 1,4-butanediamine (BDA) and pentafluorobenzoic acid (5-FBA), spin coating on the perovskite layer, and then performing annealing treatment to make the perovskite perform secondary crystallization to prepare an interface passivation layer;
[0013] Step f: spin coating (6,6)-phenyl-C 61 butyl methacrylate (PC61BM) on the interface passivation layer to prepare an electron transport layer (ETL);
[0014] Step g: spin coating 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) on the electron transport layer (ETL) to prepare an interface layer;
[0015] Step h: evaporating a silver electrode on the thin film.
[0016] As a preferred technical scheme of the present application, the step a is specifically operated as follows: first, the ITO surface is cleaned by ultrasonic cleaning with water and isopropyl alcohol respectively, and then dried in an oven; then placed in a plasma cleaning instrument for cleaning treatment at a power of 50-150 W for 1-5 min to improve the hydrophilicity of the ITO surface.
[0017] As a preferred technical scheme of the present application, the step b is specifically operated as follows: 10 mg of poly[3-(4-carboxybutyl)thiophene] (P3CT) and 160 μL of methylamine are dissolved in 1 mL of methanol to generate P3CT-N by reacting at 60 ℃ for 12 h, and then 10.5 mL of methanol is added to dilute the spin coating liquid to a concentration of 1 mg / mL, which is spin coated on the ITO surface cleaned in step a at a spin coating speed of 2000-5000 rpm for 20-30 s, and then annealed at a temperature of 80-120 ℃ for 5-15 min in a nitrogen atmosphere to prepare a hole transport layer (HTL).
[0018] As a preferred technical scheme of the present application, the step c is specifically operated as follows: (2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl) phosphonic acid (MeO-2PACz) is dissolved in isopropyl alcohol to obtain a spin coating liquid with a concentration of 1 mg / mL, which is spin coated on the hole transport layer as a SAM layer at a spin coating speed of 2000-4000 rpm for 20-40 s, and then annealed at a temperature of 80-120 ℃ for 5-15 min in a nitrogen atmosphere to prepare the SAM layer.
[0019] As a preferred technical scheme of the present application, the step d is specifically operated as follows: first, dimethylammonium lead iodide (DMAPbI3), lead iodide (PbI2), and cesium iodide (CsI) are prepared into a perovskite precursor liquid in a molar ratio of 4:1:3 by using DMF / DMSO with a volume ratio of 9:1 as a solvent, and the concentration of the cesium iodide (CsI) is 0.6-1.0 mol / L; the perovskite precursor liquid is heated and stirred at a temperature of 60 ℃ overnight, then filtered through a 0.22 μm oil filter, and then spin coated at a spin coating speed of 3000-4000 rpm for 30-50 s, and then annealed at a temperature of 180-220 ℃ for 1-5 min in an air atmosphere to obtain a black perovskite film.
[0020] As a preferred technical scheme of the present application, the step e is specifically operated as follows: 10 μL of 1,4-butanediamine (BDA) and 1 mg of pentafluorobenzoic acid (5-FBA) are added into 1 mL of isopropyl alcohol to prepare a passivation agent, and then spin coating is performed at a rotation speed of 2000-4000 rpm for 20-40 s, and after spin coating, annealing is performed at a temperature of 80-120 ℃ in a nitrogen atmosphere for 5-15 min.
[0021] As a preferred technical scheme of the present application, the step f is specifically operated as follows: (6,6)-phenyl-C 61 Methyl butyrate (PC61BM) is dissolved in chlorobenzene to obtain a spin coating solution with a concentration of 20 mg / mL, and then spin coating is performed at a rotation speed of 500-1500 rpm for 10-30 s.
[0022] As a preferred technical scheme of the present application, the step g is specifically operated as follows: 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) is dissolved in isopropyl alcohol to obtain a spin coating solution with a concentration of 1 mg / mL, and then spin coating is performed at a rotation speed of 2000-4000 rpm for 20-40 s.
[0023] As a preferred technical scheme of the present application, the step h is specifically operated as follows: the prepared thin film is subjected to Ag electrode evaporation under the conditions of a cavity pressure <2×10 -4 Pa, an evaporation rate of 0.5 Å / s, and a thickness of 100 nm.
[0024] The present application adopts 5-FBA as a collaborative passivation agent of BDA to perform P-type doping on the perovskite battery surface by one-step method, and the two are used as collaborative passivation agents to perform passivation treatment on the perovskite surface to improve the energy level of the active layer and adjust the perovskite crystal to improve the performance of the battery device after passivation treatment.
[0025] 1. The perovskite energy level can be further adjusted to reduce the energy level barrier between the perovskite and the electron transport layer (ETL), and a smaller energy barrier is beneficial to improve the electron transport efficiency and reduce the non-radiative recombination caused by the accumulation of electrons in the transmission process due to the mismatch of energy levels, which is more conducive to reducing the energy loss of the perovskite battery.
[0026] 2. The addition of 5-FBA can adjust the secondary crystallization process dominated by BDA to obtain a high-quality perovskite thin film with higher quality and fewer grain boundaries. At the same time, the dipole moment of pentafluorobenzoic acid itself can also provide a certain field passivation ability, which makes up for the shortcomings of single passivation ability and limited energy level improvement of BDA.
[0027] 3. Experiments have confirmed that the photoelectric conversion efficiency of the battery after being passivated by 5-FBA and BDA is increased from 18.57% to 20.71%. Therefore, the addition of 5-FBA can improve the performance and stability of the all-inorganic perovskite battery. BRIEF DESCRIPTION OF DRAWINGS
[0028] Figure 1 is a flow chart of the method for preparing an all-inorganic perovskite battery using pentafluorobenzoic acid and 1,4-butanediamine as a synergistic passivation agent.
[0029] Figure 2 is a comparison of the surface SEM of the perovskite battery (before spin-coating PC61BM) prepared in Example 1 (co-passivated by BDA / 5-FBA) and Comparative Example 1 (only passivated by BDA).
[0030] Figure 3 is a comparison of the surface AFM of the perovskite battery (before spin-coating PC61BM) prepared in Example 1 (co-passivated by BDA / 5-FBA) and Comparative Example 1 (only passivated by BDA).
[0031] Figure 4 is an XPS graph of the perovskite battery (before spin-coating PC61BM) prepared in Example 1 (co-passivated by BDA / 5-FBA) and Comparative Example 1 (only passivated by BDA).
[0032] Figure 5 is a UV absorption graph of the perovskite battery (before spin-coating PC61BM) prepared in Example 1 (co-passivated by BDA / 5-FBA) and Comparative Example 1 (only passivated by BDA).
[0033] Figure 6 is a PYSA graph of the perovskite battery (before spin-coating PC61BM) prepared in Example 1 (co-passivated by BDA / 5-FBA) and Comparative Example 1 (only passivated by BDA).
[0034] Figure 7 is an energy level diagram of the perovskite battery (before spin-coating PC61BM) prepared in Example 1 (co-passivated by BDA / 5-FBA) and Comparative Example 1 (only passivated by BDA).
[0035] Figure 8 is a comparison of the single electron device SCLC of the perovskite battery prepared in Example 1 (co-passivated by BDA / 5-FBA) and Comparative Example 1 (only passivated by BDA).
[0036] Figure 9 is a J-V graph of the single electron device of the perovskite battery prepared in Example 1 (co-passivated by BDA / 5-FBA) and Comparative Example 1 (only passivated by BDA). DETAILED DESCRIPTION
[0037] The present application is further described in conjunction with the following examples and drawings.
[0038] Example 1
[0039] Referring to Figure 1 As shown in the figure, a method for preparing an all-inorganic perovskite battery using pentafluorobenzoic acid and 1,4-butanediamine as a synergistic passivation agent, the specific steps are as follows:
[0040] Step a, cleaning treatment of ITO:
[0041] First, the ITO surface was cleaned with water and isopropanol respectively for two times each, and then dried in an oven for 12 h; then placed in a plasma cleaning instrument for cleaning treatment at a power of 100 W for 2 min to improve the hydrophilicity of the ITO surface.
[0042] Step b, preparation of hole transport layer (HTL):
[0043] Take 10 mg of poly[3-(4-carboxybutyl)thiophene] (P3CT), 160 μL of methylamine dissolved in 1 mL of methanol, and react at 60 ℃ for 12 h to generate P3CT-N, then add 10.5 mL of methanol to dilute to obtain a spinning solution with a concentration of 1 mg / mL, spin it on the ITO surface cleaned in step a, the spinning speed is 4000 rpm, the spinning time is 25 s, and after spinning, anneal in a nitrogen atmosphere at a temperature of 100 ℃ for 10 min to prepare the hole transport layer (HTL).
[0044] Step c, preparation of self-assembled monolayer (SAM):
[0045] Dissolve (2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl)phosphonic acid (MeO-2PACz) in isopropanol to obtain a spinning solution with a concentration of 1 mg / mL, spin it as a SAM layer on the hole transport layer, the spinning speed is 3000 rpm, the spinning time is 30 s, and after spinning, anneal in a nitrogen atmosphere at a temperature of 100 ℃ for 10 min to prepare the SAM layer.
[0046] Step d, preparation of perovskite layer:
[0047] Firstly, dimethylammonium lead iodide (DMAPbI3), lead iodide (PbI2), and cesium iodide (CsI) were prepared into a perovskite precursor solution with a molar ratio of 4:1:3 and a concentration of 1.0 mol / L of cesium iodide (CsI) using DMF / DMSO with a volume ratio of 9:1 as a solvent; the perovskite precursor solution was heated and stirred overnight at a temperature of 60°C, then filtered through a 0.22 μm oil filter and spin-coated at a spin-coating speed of 3500 rpm for 40 s; and a black perovskite thin film was obtained by annealing in an air atmosphere at a temperature of 200°C for 3.5 min.
[0048] Step e, preparation of an interface passivation layer:
[0049] A passivation agent was prepared by adding 10 μL of 1,4-butanediamine (BDA) and 1 mg of pentafluorobenzoic acid (5-FBA) to 1 mL of isopropyl alcohol, then spin-coated at a spin-coating speed of 3000 rpm for 30 s, and annealed in a nitrogen atmosphere at a temperature of 100°C for 10 min.
[0050] Step f, preparation of an electron transport layer (ETL):
[0051] (6,6)-phenyl-C 61 PC61BM was dissolved in chlorobenzene to obtain a spin-coating solution with a concentration of 20 mg / mL, then spin-coated at a spin-coating speed of 1000 rpm for 20 s.
[0052] Step g, preparation of an interface layer:
[0053] 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) was dissolved in isopropyl alcohol to obtain a spin-coating solution with a concentration of 1 mg / mL, then spin-coated at a spin-coating speed of 3000 rpm for 30 s.
[0054] Step h, evaporation of a silver electrode
[0055] The prepared thin film was subjected to Ag electrode evaporation under the following conditions: a cavity pressure <2×10 -4 Pa, an evaporation rate of 0.5 Å / s, and a thickness of 100 nm, thereby preparing a perovskite cell single electron device.
[0056] Comparative Example 1
[0057] This comparative example used only 1,4-butanediamine (BDA) as a passivation agent without adding pentafluorobenzoic acid (5-FBA), and the other steps were the same as in Example 1.
[0058] To investigate the passivation effect on the perovskite surface, the films prepared in Example 1 and Comparative Example 1 (before spin-coating PC61BM) were subjected to SEM, AFM, XPS and energy level tests, and the results were compared.
[0059] Depend on Figure 2 It can be seen that the grains on the surface of the film passivated by BDA / 5-FBA are larger and more uniform, and there are fewer grain boundaries. This is more conducive to the transport of electrons in the perovskite film and reduces energy loss.
[0060] Depend on Figure 3 It can be seen that the surface roughness of the film after passivation by BDA / 5-FBA is lower, which is conducive to the electron transport layer being more uniformly and tightly bonded to the surface of the active layer, thus facilitating electron transport.
[0061] Depend on Figure 4 It can be seen that the Pb and I elements in the film passivated by BDA / 5-FBA have larger positions. This indicates that 5-FBA has a greater effect on the Pb content of the active layer surface. 2+ with I - It has a strong binding ability. This is more conducive to reducing Pb. 2+ The convergence center formed. - Fixing the battery also helps improve battery stability.
[0062] Depend on Figure 5 It can be seen that the ultraviolet absorption edge of the film after passivation by BDA / 5-FBA remains unchanged, and the band gap of the film is calculated to be 1.72 eV using the formula Eg=1240 / λ.
[0063] Depend on Figure 6 , Figure 7 It can be seen that the LUMO energy level of the thin film passivated by BDA / 5-FBA shifts from -5.46 eV to -5.55 eV. This makes the energy level of the active layer more closely match the energy level of the electron transport layer, which is beneficial to energy loss caused by energy level mismatch. Energy level improvement is also a major factor in improving battery performance.
[0064] Depend on Figure 8 It can be seen that the V of the single-electronic device prepared in Example 1 TFL The lower density indicates a lower defect state density in the thin film. This helps reduce non-radiative recombination losses caused by surface defects, which is beneficial for improving battery performance.
[0065] Depend on Figure 9 The device parameters passivated solely by BDA are as follows: power conversion efficiency (PCE): 18.57%, current density (Jsc): 20.89 mA / cm². 2, open-circuit voltage (Voc): 1.10 V, fill factor (FF): 80.43%. The device parameters of the device passivated by BDA and 5-FBA synergistically are: photoelectric conversion efficiency (PCE): 20.71%, current density (Jsc): 20.89 mA / cm 2 , open-circuit voltage (Voc): 1.15 V, fill factor (FF): 83.92%. By comparison, it can be found that the photoelectric conversion efficiency (PCE) of the device passivated by BDA and 5-FBA synergistically is increased by 2.14%.
Claims
1. A method for preparing an all-inorganic perovskite solar cell using pentafluorobenzoic acid and 1,4-butanediamine as synergistic passivating agents, characterized in that, The steps are as follows: Step a: Perform plasma cleaning on the ITO surface to improve its hydrophilicity; Step b: Spin-coating P3CT-N dissolved in methanol onto the surface of ITO and annealing it to prepare a hole transport layer (HTL). Step c: Dissolve (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphonic acid (MeO-2PACz) in isopropanol and spin-coat it onto the hole transport layer, followed by annealing to prepare a self-assembled monolayer (SAM). Step d: The perovskite precursor solution obtained by dissolving dimethylammonium lead iodide (DMAPbI3), lead iodide (PbI2), and cesium iodide (CsI) in DMF / DMSO was spin-coated onto a self-assembled monolayer (SAM), followed by annealing to prepare the perovskite layer; Step e: Mix 1,4-butanediamine (BDA) with pentafluorobenzoic acid (5-FBA), spin-coat the mixture onto the perovskite layer, and then anneal it to allow the perovskite to undergo secondary crystallization, thus preparing an interface passivation layer. Step f: Spin-coating (6,6)-phenyl-C onto the interface passivation layer 61 methyl butyrate (PC61BM) was used to prepare an electron transport layer (ETL). Step g: Spin-coating 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) onto the electron transport layer (ETL) to prepare the interface layer; Step h: Deposit a silver electrode onto the thin film by vapor deposition.
2. The method as described in claim 1, characterized in that, The specific operation of step a is as follows: First, the ITO surface is ultrasonically cleaned with water and isopropanol respectively, and then dried in an oven; then it is placed in a plasma cleaner and cleaned with a power of 50~150 W for 1~5 min to improve the hydrophilicity of the ITO surface.
3. The method as described in claim 1, characterized in that, The specific operation of step b is as follows: 10 mg of poly[3-(4-carboxybutylthiophene] (P3CT) and 160 μL of methylamine are dissolved in 1 mL of methanol and reacted at 60 °C for 12 h to generate P3CT-N. Then, 10.5 mL of methanol is added to dilute the solution to obtain a spin-coating solution with a concentration of 1 mg / mL. The solution is then spin-coated onto the ITO surface cleaned in step a. The spin-coating speed is 2000~5000 rpm and the spin-coating time is 20~30 s. After spin-coating, the hole transport layer (HTL) is prepared by annealing at 80~120 °C for 5~15 min in a nitrogen atmosphere.
4. The method as described in claim 1, characterized in that, The specific operation of step c is as follows: (2-(3,6-dimethoxy-9H-carbazole-9-yl)ethyl)phosphonic acid (MeO-2PACz) is dissolved in isopropanol to obtain a spin-coating solution with a concentration of 1 mg / mL. This solution is then used as the SAM layer and spin-coated onto the hole transport layer. The spin-coating speed is 2000~4000 rpm and the spin-coating time is 20~40 s. After spin-coating, the SAM layer is prepared by annealing at a temperature of 80~120℃ for 5~15 min in a nitrogen atmosphere.
5. The method as described in claim 1, characterized in that, The specific operation of step d is as follows: First, using DMF / DMSO with a volume ratio of 9:1 as the solvent, a perovskite precursor solution is prepared by mixing dimethylammonium lead iodide (DMAPbI3), lead iodide (PbI2), and cesium iodide (CsI) with a molar ratio of 4:1:3, wherein the concentration of cesium iodide (CsI) is 0.6~1.0 mol / L; the perovskite precursor solution is heated and stirred overnight at 60 ℃, and then filtered through a 0.22 μm oily filter before spin coating. The spin coating speed is 3000~4000 rpm and the spin coating time is 30~50 s. After spin coating, the film is annealed in air at a temperature of 180~220℃ for 1~5 min to obtain a black perovskite film.
6. The method as described in claim 1, characterized in that, The specific operation of step e is as follows: 10 μL of 1,4-butanediamine (BDA) and 1 mg of pentafluorobenzoic acid (5-FBA) are added to 1 mL of isopropanol to prepare a passivating agent, and then spin-coating is performed at a speed of 2000~4000 rpm for 20~40 s. After spin-coating, the agent is annealed at a temperature of 80~120℃ for 5~15 min in a nitrogen atmosphere.
7. The method as described in claim 1, characterized in that, The specific operation of step f is as follows: (6,6)-phenyl-C 61 Methyl butyrate (PC61BM) was dissolved in chlorobenzene to obtain a spin-coating solution with a concentration of 20 mg / mL. Spin coating was then performed at a speed of 500-1500 rpm for 10-30 s.
8. The method as described in claim 1, characterized in that, The specific operation of step g is as follows: 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) is dissolved in isopropanol to obtain a spin-coating solution with a concentration of 1 mg / mL, and then spin-coated at a speed of 2000~4000 rpm for a spin-coating time of 20~40 s.
9. The method as described in claim 1, characterized in that, The specific operation of step h is as follows: the prepared thin film is subjected to a cavity pressure <2×10 -4 Ag electrode deposition was performed under the conditions of Pa, deposition rate of 0.5 Å / s, and thickness of 100 nm.
10. An all-inorganic perovskite solar cell prepared by the method according to any one of claims 1 to 9.