Preparation method of carbon-based hole-transport-layer-free perovskite solar cell

Abstract

The application relates to a preparation method of a carbon-based hole-free transport layer perovskite solar cell, and belongs to the perovskite solar cell field.The perovskite solar cell comprises, from bottom to top, a glass substrate, an electron transport layer, a perovskite layer and a carbon electrode; the specific preparation steps are as follows: the glass substrate is cleaned, the electron transport layer is deposited on the cleaned glass substrate through a spin coating method, a perovskite precursor solution is prepared and uniformly coated on the surface of the electron transport layer through the spin coating method, the perovskite layer is obtained through annealing, the carbon paste is scraped on the perovskite layer, and the carbon electrode is obtained after annealing. In the preparation process of the perovskite precursor solution, 1,3-propanediamine hydrochloride is added as an additive, so that the defect density is effectively reduced, the film quality is optimized, and the device performance is improved.

Description

Technical Field

[0001] This invention belongs to the field of perovskite solar cells, and mainly relates to a method for preparing and applying a low-cost, high-efficiency carbon-based perovskite solar cell. Background Technology

[0002] Solar cells convert light energy into electrical energy using the photovoltaic effect, making them a highly efficient energy utilization technology. Various types of photovoltaic devices have been developed. Among them, perovskite solar cells have become a research focus due to their superior photoelectric conversion efficiency, tunable bandgap, abundant raw materials, and simple fabrication process. In just over a decade, their photoelectric performance has improved rapidly, with their photoelectric conversion efficiency increasing from 3.8% to the current 26.1%. The rapid development of perovskite solar cells demonstrates enormous development potential and commercial prospects. However, the hole transport layer and back electrode used in conventional perovskite structures are not only expensive and have complex deposition processes, but are also prone to ion migration, making it difficult to guarantee device stability and hindering their further commercial development. Summary of the Invention

[0003] The purpose of this invention is to provide a method for preparing a carbon-based perovskite solar cell without a hole transport layer, which solves the cost and process problems caused by hole transport layer materials and metal electrode materials, and prepares a perovskite solar cell with excellent efficiency, good stability and low cost.

[0004] To achieve the above objectives, the present invention is implemented as follows:

[0005] A method for fabricating carbon-based perovskite solar cells without hole transport layers, characterized in that:

[0006] A perovskite solar cell, from bottom to top, consists of a glass substrate, an electron transport layer, a perovskite layer, and a carbon electrode; the specific fabrication steps are as follows:

[0007] S1 cleans the glass substrate;

[0008] S2 deposits an electron transport layer on a cleaned glass substrate using a spin-coating method.

[0009] S3 is used to prepare perovskite precursor solutions:

[0010] Lead iodide, methylammonium iodide (MAI), formamide hydroiodide (FAI), cesium iodide, and 1,3-propanediamine hydrochloride (PDADCl) were dissolved in an organic solvent and stirred thoroughly for 5–8 h. The molar concentrations were 1–1.5 mol / L for lead iodide, 0.8–1.3 mol / L for methylammonium iodide, 0.1–0.3 mol / L for formamide hydroiodide, 0.02–0.1 mol / L for cesium iodide, and 0.01–0.03 mol / L for 1,3-propanediamine hydrochloride. The organic solvent was a mixture of dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) in a volume ratio of 4:1 to 9:1.

[0011] S4 The perovskite precursor solution prepared in S3 is uniformly coated on the surface of the electron transport layer by spin coating, and the perovskite wet film is annealed to obtain the perovskite layer.

[0012] S5 involves coating a carbon paste onto a perovskite layer and annealing it to obtain the carbon electrode.

[0013] Further, the cleaning described in step S1 refers to ultrasonically cleaning the glass substrate for 10-20 minutes with ethanol, daily detergent, deionized water, isopropanol and ethanol respectively, then drying it at 50-70°C for 10-15 minutes, and then treating it with ultraviolet ozone (UV) for 10-20 minutes.

[0014] Further, the electron transport layer deposited in step S2 refers to mixing 15-17 wt% tin dioxide aqueous dispersion and deionized water at a volume ratio of 1:5 to obtain a tin oxide solution, and then uniformly coating the tin oxide solution onto a glass substrate at a depth of 1×1 cm. 2 A 40–60 μL solution of tin oxide is coated onto a glass substrate. The spin coater is started, the spin coating speed is 4000 r / min, and the spin coating time is 30 s. After spin coating, the substrate is heated at 130–150 °C for 20–30 min to obtain the electron transport layer.

[0015] Further, the coating of the perovskite precursor solution in step S4 refers to: filtering the uniformly stirred perovskite precursor solution using a disposable sterile syringe with a polytetrafluoroethylene organic filter membrane, and then uniformly coating it onto the electron transport layer at a depth of 1×1 cm. 2 A 50 μL perovskite precursor solution was coated onto the electron transport layer. The spin coater was started, the spin coating speed was 4000 r / min, and the spin coating time was 30 s. During the high-speed rotation for 6 to 8 s, the antisolvent chlorobenzene was added dropwise, and the volume of the added dropwise solution was 4 times the volume of the perovskite precursor solution.

[0016] Furthermore, the perovskite wet film annealing treatment described in step S4 refers to heating the deposited perovskite wet film at 100–120°C for 12–18 minutes.

[0017] Furthermore, the carbon paste used in step S5 is a commercially available conductive carbon paste. The carbon paste is applied to the surface of the perovskite layer using a scraper and heated at 100–120°C for 15–20 minutes.

[0018] The positive effects of this invention are as follows:

[0019] (1) This invention effectively reduces defect density, optimizes film quality, and improves device performance by adding 1,3-propanediamine hydrochloride (PDADCl) as an additive during the preparation of the perovskite precursor solution. The amino group in PDADCl can passivate Pb in the perovskite. 2+ Vacancy and MA + The addition of chloride ions reduces negative charge defects, while Cl- can combine with I- vacancies in the perovskite to passivate positive charge defects and increase solubility. Furthermore, chloride ion additives help regulate the formation of perovskite films, thereby improving crystallinity and film quality. Simultaneously, this invention prepares a tricationic mixed perovskite solution. By adding a small amount of cesium iodide to the perovskite precursor solution, cation vacancies formed by the volatilization of organic cations can be filled, reducing defect density and decreasing lead iodide precipitation, effectively improving device performance and stability.

[0020] (2) The entire fabrication process of the carbon-based perovskite solar cell without a hole transport layer of the present invention is carried out at low temperature, without the need for high-temperature calcination. The fabrication process eliminates the need for expensive hole transport layer materials and uses carbon materials instead of metal materials for the electrodes, greatly reducing production costs and simplifying the process. This perovskite solar cell fabrication method is simple, low-cost, and highly reproducible, providing valuable insights for the future production of low-cost, high-performance perovskite solar cells. Detailed Implementation

[0021] Example 1

[0022] A method for fabricating a carbon-based perovskite solar cell without a hole transport layer. The perovskite solar cell, from bottom to top, consists of a glass substrate, an electron transport layer, a perovskite layer, and a carbon electrode.

[0023] The specific preparation steps are as follows:

[0024] Step S1: Clean the glass substrate. (The text abruptly ends here, likely due to an incomplete sentence or a formatting 2 The indium tin oxide (ITO) glass substrate was ultrasonically cleaned for 15 minutes by immersion in 200 ml of ethanol, daily detergent, deionized water, isopropanol and ethanol, then dried in an oven at 70°C for 15 minutes, and then treated with ultraviolet ozone (UV) for 10 minutes.

[0025] Step S2: Prepare an electron transport layer on the substrate described in S1. Mix 200 μL of 15 wt% tin dioxide (SnO2) aqueous dispersion with 1 mL of deionized water and stir thoroughly to obtain a tin oxide solution. Then, take 45 μL of the tin oxide solution and coat it onto the ITO glass substrate of S1. Start the spin coater, spin coat at a speed of 4000 r / min for 30 s, and anneal at 150 °C for 30 min to obtain the tin dioxide electron transport layer.

[0026] Step S3: Prepare the perovskite precursor solution. Weigh 1.5 mmol lead iodide, 1.3 mmol ammonium methyl iodide (MAI), 0.15 mmol formamide hydroiodide (FAI), 0.05 mmol cesium iodide (CsI), and 0.03 mmol 1,3-propanediamine hydrochloride (PDADCl) and dissolve them in a mixed solvent of 100 μL dimethyl sulfoxide (DMSO) and 900 μL dimethylformamide (DMF) (total mixed solvent volume is 1 mL) to form the perovskite precursor solution, and stir thoroughly for 8 h. Step S4: Spin-coat the perovskite precursor solution prepared in S3 onto the electron transport layer to prepare the perovskite layer. Filter the well-stirred perovskite precursor solution using a disposable sterile syringe with a polytetrafluoroethylene organic filter membrane. Use a pipette to apply 50 μL of the perovskite precursor solution onto a 1×1 cm plate from S2. 2 On a glass substrate, spin coating is performed at 4000 r / min for 30 s. 200 μL of anti-solvent chlorobenzene is then dropped onto the electron transport layer during high-speed rotation for 6–8 s. Finally, the perovskite layer is obtained by annealing at 120 °C for 12 min.

[0027] Step S5: Using a glass slide, apply a small amount of carbon paste directly to the surface of the S4 perovskite layer to completely cover the perovskite layer. After annealing at 100°C for 20 minutes, a carbon electrode is obtained.

[0028] The performance of the prepared carbon-based perovskite solar cells without hole transport layers is shown in Table 2.

[0029] Examples 2-4, Comparative Examples 1-4

[0030] Each step is the same as in Example 1, and the formulation of the perovskite precursor solution is shown in Table 1.

[0031] Table 1

[0032] Lead iodide Methylammonium iodide Methionyl hydroiodide Cesium iodide 1,3-Propanediamine hydrochloride Example 1 1.5 1.3 0.15 0.05 0.03 Example 2 1.5 1.1 0.3 0.1 0.03 Example 3 1.2 1 0.18 0.02 0.02 Example 4 1 0.8 0.1 0.1 0.01 Compare with Example 1 1.5 1.3 0.15 0.05 / Compare with Example 2 1.5 1.1 0.3 0.1 / Compare with Example 3 1.5 1.3 0.2 / / Compare with Example 4 1.5 1.1 0.4 / /

[0033] Battery performance specifications are shown in Table 2.

[0034] Example 5

[0035] The fabrication method of carbon-based perovskite solar cells without hole transport layer, and the specific steps of the fabrication are as follows:

[0036] Step S1: Clean the glass substrate. (The text abruptly ends here, likely due to an incomplete sentence or a formatting 2 The indium tin oxide (ITO) glass substrate was ultrasonically cleaned for 20 minutes by immersion in 200 ml of ethanol, daily detergent, deionized water, isopropanol and ethanol, then dried in an oven at 50°C for 12 minutes, and then treated with ultraviolet ozone (UV) for 20 minutes.

[0037] Step S2: Prepare an electron transport layer on the substrate described in S1. Mix 200 μL of 17 wt% tin dioxide (SnO2) aqueous dispersion with 1 mL of deionized water and stir thoroughly to obtain a tin oxide solution. Then, take 40 μL of the tin oxide solution and coat it onto the ITO glass substrate of S1. Start the spin coater, spin coat at a speed of 4000 r / min for 30 s, and anneal at 130 °C for 20 min to obtain the tin dioxide electron transport layer.

[0038] Step S3: Prepare the perovskite precursor solution. Lead iodide, methylammonium iodide (MAI), formamide hydroiodide (FAI), cesium iodide (CsI), and 1,3-propanediamine hydrochloride (PDADCl) are weighed in the same amounts as in Example 1, and dissolved in a mixed solvent of 200 μL dimethyl sulfoxide (DMSO) and 800 μL dimethylformamide (DMF) (total mixed solvent volume is 1 mL) to form the perovskite precursor solution. Stir thoroughly for 6 h.

[0039] Step S4: Spin-coat the perovskite precursor solution described in S3 onto the electron transport layer to prepare the perovskite layer. Filter the thoroughly stirred perovskite precursor solution using a disposable sterile syringe with a polytetrafluoroethylene organic filter membrane. Use a pipette to apply 50 μL of the perovskite precursor solution onto a 1×1 cm area as described in S2. 2 On a glass substrate, spin-coating was performed at 4000 r / min for 30 s. 200 μL of the anti-solvent chlorobenzene was then dropped onto the electron transport layer during high-speed rotation for 6–8 s. The perovskite layer was then obtained by annealing at 100 °C for 18 min.

[0040] Step S5: Using a glass slide, apply a small amount of carbon paste directly to the surface of the S4 perovskite layer to completely cover the perovskite layer. After annealing at 100°C for 15 minutes, a carbon electrode is obtained.

[0041] Battery performance indicators are shown in Table 2.

[0042] Example 6

[0043] The fabrication method of carbon-based perovskite solar cells without hole transport layer, and the specific steps of the fabrication are as follows:

[0044] Step S1: Clean the glass substrate. (The text abruptly ends here, likely due to an incomplete sentence or a formatting 2The indium tin oxide (ITO) glass substrate was ultrasonically cleaned for 10 minutes by immersion in 200 ml of ethanol, daily detergent, deionized water, isopropanol and ethanol, then dried in an oven at 60°C for 10 minutes, and then treated with ultraviolet ozone (UV) for 15 minutes.

[0045] Step S2: Prepare an electron transport layer on the substrate described in S1. Mix 200 μL of 16 wt% tin dioxide (SnO2) aqueous dispersion with 1 mL of deionized water and stir thoroughly to obtain a tin oxide solution. Then, take 50 μL of the tin oxide solution and coat it onto the ITO glass substrate of S1. Start the spin coater, spin coat at a speed of 4000 r / min for 30 s, and anneal at 140 °C for 25 min to obtain the tin dioxide electron transport layer.

[0046] Step S3: Prepare the perovskite precursor solution. Lead iodide, methylammonium iodide (MAI), formamide hydroiodide (FAI), cesium iodide (CsI), and 1,3-propanediamine hydrochloride (PDADCl) are weighed in the same amounts as in Example 1, and dissolved in a mixed solvent of 300 μL dimethyl sulfoxide (DMSO) and 700 μL dimethylformamide (DMF) (total mixed solvent volume is 1 mL) to form the perovskite precursor solution. Stir thoroughly for 5 h.

[0047] Step S4: Spin-coat the perovskite precursor solution described in S3 onto the electron transport layer to prepare the perovskite layer. Filter the thoroughly stirred perovskite precursor solution using a disposable sterile syringe with a polytetrafluoroethylene organic filter membrane. Use a pipette to apply 50 μL of the perovskite precursor solution onto a 1×1 cm area as described in S2. 2 On a glass substrate, spin-coating was performed at 4000 r / min for 30 s. 200 μL of the anti-solvent chlorobenzene was then dropped onto the electron transport layer during high-speed rotation for 6–8 s. The perovskite layer was then obtained by annealing at 110 °C for 15 min.

[0048] Step S5: Using a glass slide, apply a small amount of carbon paste directly to the surface of the S4 perovskite layer to completely cover the perovskite layer. After annealing at 120°C for 15 minutes, a carbon electrode is obtained.

[0049] Battery performance specifications are shown in section 2.

[0050] Example 7

[0051] The fabrication method of carbon-based perovskite solar cells without hole transport layer, and the specific steps of the fabrication are as follows:

[0052] Step S1: Clean the glass substrate. (The text abruptly ends here, likely due to an incomplete sentence or a formatting 2The indium tin oxide (ITO) glass substrate was ultrasonically cleaned for 20 minutes by immersion in 200 ml of ethanol, daily detergent, deionized water, isopropanol and ethanol, then dried in an oven at 50°C for 12 minutes, and then treated with ultraviolet ozone (UV) for 20 minutes.

[0053] Step S2: Prepare an electron transport layer on the substrate described in S1. Mix 200 μL of 17 wt% tin dioxide (SnO2) aqueous dispersion with 1 mL of deionized water and stir thoroughly to obtain a tin oxide solution. Then, take 60 μL of the tin oxide solution and coat it onto the ITO glass substrate of S1. Start the spin coater, spin coat at a speed of 4000 r / min for 30 s, and anneal at 130 °C for 20 min to obtain the tin dioxide electron transport layer.

[0054] Step S3: Prepare the perovskite precursor solution. Lead iodide, methylammonium iodide (MAI), formamide hydroiodide (FAI), cesium iodide (CsI), and 1,3-propanediamine hydrochloride (PDADCl) were weighed in the same amounts as in Example 1, and dissolved in a mixed solvent of 400 μL dimethyl sulfoxide (DMSO) and 600 μL dimethylformamide (DMF) (total mixed solvent volume: 1 mL) to form the perovskite precursor solution. The solution was stirred thoroughly for 6 h.

[0055] Step S4: Spin-coat the perovskite precursor solution described in S3 onto the electron transport layer to prepare the perovskite layer. Filter the thoroughly stirred perovskite precursor solution using a disposable sterile syringe with a polytetrafluoroethylene organic filter membrane. Use a pipette to apply 50 μL of the perovskite precursor solution onto a 1×1 cm area as described in S2. 2 On a glass substrate, spin-coating was performed at 4000 r / min for 30 s. 200 μL of the anti-solvent chlorobenzene was then dropped onto the electron transport layer during high-speed rotation for 6–8 s. The perovskite layer was then obtained by annealing at 100 °C for 18 min.

[0056] Step S5: Using a glass slide, apply a small amount of carbon paste directly to the surface of the S4 perovskite layer to completely cover the perovskite layer. After annealing at 100°C for 15 minutes, a carbon electrode is obtained.

[0057] Battery performance specifications are shown in section 2.

[0058] Table 2

[0059]

[0060]

[0061] By comparing the data of Comparative Examples 1 and 3, and Comparative Examples 2 and 4 in Table 2, it can be found that the open-circuit voltage and filling capacity of the device were significantly improved after adding a small amount of Cs to the perovskite precursor solution. This indicates that Cs ions can fill the vacancies of organic cations, thereby reducing negative charge defects, reducing lead iodide precipitation, and improving device performance.

[0062] A comparison of the data in Table 2 between Example 1 and Comparative Example 1, and between Example 2 and Comparative Example 2, reveals that the perovskite solar cells with the 1,3-propanediamine hydrochloride (PDADCl) additive exhibit superior photoelectric performance compared to those without the additive. Furthermore, a comparison between Examples 1-4 and Comparative Examples 1-2 shows that for perovskite precursor solutions of different concentrations and cation ratios, the device performance after adding 1,3-propanediamine hydrochloride (PDADCl) additive is also superior to the device without the additive. This indicates that the 1,3-propanediamine hydrochloride (PDADCl) additive selected in this invention can effectively passivate positive and negative charge defects in perovskite, increase grain size, improve film quality, thereby promoting carrier transport and enhancing cell performance and stability.

[0063] By comparing the data from the examples, the precursor concentration, formulation, and process parameters used in Example 1 are optimal.

Claims

1. A method for fabricating a carbon-based perovskite solar cell without a hole transport layer, characterized in that: A perovskite solar cell, from bottom to top, consists of a glass substrate, an electron transport layer, a perovskite layer, and a carbon electrode. The specific preparation steps are as follows: S1 Cleans the glass substrate; S2 deposits an electron transport layer on a cleaned glass substrate using a spin-coating method; S3 Preparation of perovskite precursor solution: Lead iodide, methylammonium iodide (MAI), formamide hydroiodide (FAI), cesium iodide, and 1,3-propanediamine hydrochloride (PDADCl) were dissolved in an organic solvent and stirred thoroughly for 5-8 hours. The molar concentrations were 1-1.5 mol / L for lead iodide, 0.8-1.3 mol / L for methylammonium iodide, 0.1-0.3 mol / L for formamide hydroiodide, 0.02-0.1 mol / L for cesium iodide, and 0.01-0.03 mol / L for 1,3-propanediamine hydrochloride. The organic solvent was a mixture of dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) in a volume ratio of 4:1 to 9:

1. S4 The perovskite precursor solution prepared in S3 is uniformly coated on the surface of the electron transport layer by spin coating, and the perovskite wet film is annealed to obtain the perovskite layer. S5. Carbon paste is coated onto the perovskite layer and annealed to obtain the carbon electrode.

2. The method for fabricating a carbon-based perovskite solar cell without a hole transport layer according to claim 1, characterized in that... The cleaning described in step S1 refers to ultrasonically cleaning the glass substrate for 10-20 minutes each with ethanol, daily detergent, deionized water, isopropanol and ethanol in sequence, followed by drying at 50-70°C for 10-15 minutes, and then treating it with ultraviolet ozone for 10-20 minutes.

3. The method for fabricating a carbon-based perovskite solar cell without a hole transport layer according to claim 1, characterized in that... The electron transport layer deposited in step S2 refers to a tin oxide solution obtained by mixing 15-17 wt% tin dioxide aqueous dispersion and deionized water at a volume ratio of 1:5, and then uniformly coating the tin oxide solution onto a glass substrate at a depth of 1×1 cm. 2 A 40-60 μL solution of tin oxide is coated onto a glass substrate. The spin coater is started, the spin coating speed is 4000 r / min, and the spin coating time is 30 s. After spin coating, the substrate is heated at 130-150℃ for 20-30 min to obtain the electron transport layer.

4. The method for fabricating a carbon-based perovskite solar cell without a hole transport layer according to claim 1, characterized in that... The coating of the perovskite precursor solution in step S4 refers to: filtering the uniformly stirred perovskite precursor solution through a disposable sterile syringe with a polytetrafluoroethylene organic filter membrane, and then uniformly coating it onto the electron transport layer at a depth of 1×1 cm. 2 A 50 μL perovskite precursor solution was coated onto the electron transport layer. The spin coater was started, the spin coating speed was 4000 r / min, and the spin coating time was 30 s. During the high-speed spin of 6 to 8 s, the antisolvent chlorobenzene was added dropwise, and the volume of the added dropwise solution was 4 times the volume of the perovskite precursor solution.

5. The method for fabricating a carbon-based perovskite solar cell without a hole transport layer according to claim 1, characterized in that... The perovskite wet film annealing treatment in step S4 refers to heating the deposited perovskite wet film at 100~120℃ for 12~18 minutes.

6. The method for preparing a carbon-based perovskite solar cell without a hole transport layer according to claim 1, characterized in that... The carbon paste used in step S5 is a commercially available conductive carbon paste. The carbon paste is applied to the surface of the perovskite layer using a scraper and heated at 100~120℃ for 15~20 minutes.

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