A low-temperature preparation method of a full-printing flexible perovskite device

Abstract

The application relates to a low-temperature preparation method of a full-printing flexible perovskite device, which comprises the following steps: taking a flexible substrate PEN-ITO as a base, taking a SnO2 colloid and deionized water mixed solution as raw materials, using a doctor blade device, annealing, and preparing a low-temperature electron transport layer; taking perovskite ink as raw materials, adopting a screen printing process, annealing, and preparing a low-temperature perovskite layer on the basis of the low-temperature electron transport layer; taking carbon electrode paste as raw materials, adopting a screen printing process, annealing, and preparing a low-temperature electrode layer. The perovskite light-absorbing layer, the transport layer and the top electrode layer are prepared by printing under a low-temperature condition, the problem that the flexible perovskite device is difficult to controllably prepare under a low temperature is solved, and efficient preparation of the flexible perovskite device under a condition of <120 DEG C is realized.

Description

Technical Field

[0001] This invention belongs to the field of photovoltaic device fabrication technology, specifically a low-temperature fabrication method for a fully printed flexible perovskite device. Background Technology

[0002] Solar energy is a clean and pollution-free renewable energy source, and its acquisition at a higher efficiency and lower cost has attracted widespread research and attention. Organic-inorganic hybrid perovskite solar cells, due to their advantages such as low cost, solution-processability, and high efficiency, are a major research direction for next-generation photovoltaic devices. Flexible perovskite solar cells, with their excellent photoelectric performance, light weight, low cost, and high production feasibility, have experienced rapid development in recent years. Compared with rigid silicon-based solar cells, flexible perovskite exhibits unique commercial value and can be widely used in wearable electronics, smart vehicles, medical testing, building integration, and other industries. Meanwhile, printing technology has outstanding advantages such as low cost, high raw material utilization, and simple fabrication process, making it the main fabrication process for flexible perovskite photovoltaic devices. Compared with rigid perovskite printed devices, flexible printed perovskite devices have significantly lower efficiency. This is mainly because the high-temperature annealing process used in the fabrication of flexible devices causes deformation of the flexible materials (PEN-ITO, PET-ITO), severely affecting the fabrication of subsequent functional layers and devices, and reducing the reproducibility of the devices. Therefore, it is imperative to develop a method for fabricating efficient flexible perovskite devices under low-temperature conditions. Summary of the Invention

[0003] To overcome the shortcomings of traditional flexible photovoltaic device fabrication, such as the high-temperature substrate being easily deformed and the perovskite film having poor quality, this invention proposes a low-temperature fabrication method for fully printed flexible perovskite devices.

[0004] The technical solution adopted by this invention to solve its technical problem is:

[0005] A low-temperature fabrication method for a fully printed flexible perovskite device includes the following steps:

[0006] Step 1, Fabrication of a low-temperature electron transport layer

[0007] Using a flexible PEN-ITO substrate as the base and a mixture of SnO2 colloid and deionized water as the raw material, an initial low-temperature electron transport layer was prepared using a blade coating device.

[0008] The coating process is controlled as follows: the substrate is placed on the coating machine, the preheating temperature is b1, b1 = 20–80℃, the preheating time is c1, c1 = 5–20 min, the distance between the coating blade and the substrate is d1, d1 = 0.1–0.3 mm, and the coating speed is e1, e1 = 0.10–10 mm / s. This yields the initial low-temperature electron transport layer.

[0009] The initial low-temperature electron transport layer was annealed in a constant-temperature chamber at a temperature of f1 (100–120 °C) for a time of g1 (10–180 min). This yielded a dense SnO2 thin film, i.e., the low-temperature electron transport layer.

[0010] Step 2, Preparation of low-temperature perovskite layer

[0011] Based on the low-temperature electron transport layer, an initial low-temperature perovskite layer is prepared using perovskite ink as raw material and a screen printing process.

[0012] An initial low-temperature perovskite layer was prepared by screen printing. The mesh count of the screen was h1, h1 = 300-500, the temperature was b2, b2 = 20-50℃, the printing pitch was d2, d2 = 0.5-1mm, the printing pressure was i1, i1 = 0.10-0.20MPa, and the printing speed was e2, e2 = 5-50cm / s. This resulted in an initial low-temperature perovskite layer based on the low-temperature electron transport layer.

[0013] The initial low-temperature perovskite layer was placed in a constant temperature oven for annealing. The annealing temperature was f2, f2 = 80~100℃, and the annealing time was g2, g2 = 1~10min, to obtain a perovskite film, i.e., a low-temperature perovskite layer.

[0014] Step 3, Prepare the low-temperature electrode layer

[0015] An initial low-temperature electrode layer was prepared using a screen printing process based on a low-temperature perovskite layer and carbon electrode paste as raw material.

[0016] The carbon electrode paste is transferred to the surface of a printing screen, and screen printing is performed on the low-temperature perovskite layer. The screen mesh number is h2, h2 = 150~250, the printing pitch is d3, d3 = 0.5~1mm, the printing pressure is i2, i2 = 0.1~0.2MPa, the printing speed is e3, e3 = 5~20cm / s, and the temperature is c2, c2 = 20~50℃, to obtain the initial low-temperature electrode layer.

[0017] The initial low-temperature electrode layer was placed in a constant temperature oven for annealing at a temperature of f3 (50–80 °C) and a time of g3 (5–20 min) to obtain a low-temperature carbon electrode, i.e., a low-temperature electrode layer.

[0018] The above-mentioned low-temperature fabrication method for fully printed flexible perovskite devices, wherein step 1, fabrication of the low-temperature electron transport layer, further includes:

[0019] The preparation process of the SnO2 colloid and deionized water mixture is as follows: SnO2 colloid is placed in deionized water, the volume ratio of SnO2 colloid to deionized water is a1, a1 = 1:3~10, and ultrasonically dispersed for 20 min to obtain the SnO2 colloid and deionized water mixture.

[0020] The above-mentioned low-temperature fabrication method for fully printed flexible perovskite devices, wherein step 2, fabricating the low-temperature perovskite layer, further includes:

[0021] The component is FA X MA 1-X PbI3 perovskite raw material is dissolved in methylamine acetate, heated to 100°C, stirred for 6 hours, and placed in an environment at 0°C for 1 hour to obtain perovskite ink for screen printing.

[0022] The above-mentioned low-temperature fabrication method for fully printed flexible perovskite devices, wherein step 3, fabrication of the low-temperature electrode layer, further includes:

[0023] The preparation process of carbon electrode slurry is as follows: graphite with a particle size of 5 μm, carbon black with a particle size of 20 nm, and hydroxyethyl cellulose with a viscosity of 50 mPa·s are placed into a ball mill jar in sequence. The weight ratio of carbon black to graphite is a3, where a3 = 1:3~5. The mixture is heated to 100℃ until dehydration, and then terpineol is added. The mixture is ball milled for 3 hours to obtain carbon electrode slurry.

[0024] The beneficial effects of this invention are:

[0025] A low-temperature fabrication method for fully printed flexible perovskite devices solves the problem of difficult and controllable low-temperature fabrication of flexible perovskite devices by printing a perovskite light-absorbing layer, a transport layer, and a top electrode layer under low-temperature conditions, and achieves efficient fabrication of flexible perovskite devices at temperatures below 120°C. Attached Figure Description

[0026] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0027] Figure 1a This describes the surface morphology of the low-temperature perovskite layer in this invention.

[0028] Figure 1b This is the cross-sectional morphology of the low-temperature perovskite layer of the present invention;

[0029] Figure 2 This is a schematic diagram of the structure of the present invention;

[0030] Figure 3 This is a schematic diagram of the voltage and current density relationship in Example 1. Detailed Implementation

[0031] Examples 1, 2, and 3

[0032] A low-temperature fabrication method for a fully printed flexible perovskite device includes the following steps:

[0033] Step 1, Fabrication of a low-temperature electron transport layer

[0034] SnO2 colloid was mixed with deionized water and ultrasonically dispersed for 20 minutes. The ratio was a1, a1 = 1:3-1:10. A flexible PEN-ITO substrate was placed on a doctor blade coater and preheated to b1, b1 = 20-80℃ for c1, c1 = 5-20 minutes. The distance between the doctor blade and the substrate was adjusted to d1, d1 = 0.1-0.3 mm, and the coating speed was controlled to e1, e1 = 0.1-10 mm / s, dragging the doctor blade to leave a SnO2 film on the substrate. Then, it was transferred to a hot plate for annealing at f1 = 100-120℃ for g1, g1 = 10-180 minutes to obtain a dense SnO2 film.

[0035] Step 2, Preparation of low-temperature perovskite layer

[0036] The perovskite raw material was dissolved in the ionic liquid methylamine acetate (MAAc), the solution was heated to 100°C and stirred for 6 hours, and then cooled at 0°C for 1 hour to obtain screen printing perovskite ink.

[0037] The perovskite ink for screen printing is transferred to the surface of the printing screen. The perovskite composition is FA. a2 MA a2 PbI3, a2 = 0-1, was used for screen printing of perovskite thin films. The screen printing parameters were: screen mesh number h1 = 300-500, substrate temperature b2 = 20-50℃, printing pitch d2 = 0.5-1mm, printing pressure i1 = 0.1-0.2MPa, and printing speed e2 = 5-50cm / s. The wet perovskite film was then transferred to a hot plate for annealing at f2 = 80-100℃ for 1-10min to obtain the perovskite thin film.

[0038] Step 3, Prepare the low-temperature electrode layer

[0039] The preparation process of carbon electrode slurry is as follows: graphite with a particle size of 5μm, carbon black with a particle size of 20nm, and hydroxyethyl cellulose with a viscosity of 50mPa·s are placed into a ball mill jar in sequence, heated to 100℃, dehydrated, and then terpineol is added. The mixture is ball milled for 3 hours to obtain carbon electrode slurry.

[0040] The carbon electrode paste was transferred to the surface of a printing screen. The carbon electrode composition was carbon black and graphite, with a carbon black to graphite ratio of a3 (a3 = 1:3-1:5). The screen printing parameters were: screen mesh number h2 (h2 = 150-250), printing pitch d3 (d3 = 0.5-1 mm), printing pressure i2 (i2 = 0.1-0.2 MPa), printing speed e3 (e2 = 5-20 cm / s), and substrate temperature c2 (c2 = 20-50 °C). The resulting wetted carbon electrode film was then transferred to a vacuum hot stage for annealing at a temperature f3 (f3 = 50-80 °C) for a time g3 (g3 = 5-20 min). This process produced a low-temperature carbon electrode and completed the fabrication of the device.

[0041] Table 1, Relevant Parameters

[0042]

[0043]

[0044] Device performance testing process and results:

[0045] The performance of the fully printed flexible perovskite device prepared in Example 1 was tested. The test results showed that the energy conversion efficiency of the fully printed flexible perovskite device was 10.84%, of which the open-circuit voltage V OC The voltage is 0.863V, and the short-circuit current is J. SC 21.06 mA / cm 2 FF is 0.596.

Claims

1. A low-temperature fabrication method for a fully printed flexible perovskite device, characterized in that, Includes the following steps: Step 1, Fabrication of a low-temperature electron transport layer: Using flexible PEN-ITO substrate as the base and SnO2 colloid and deionized water mixture as raw material, an initial low-temperature electron transport layer was prepared using a blade coating device. The control of the coating process is as follows: place the substrate on the coating machine, preheat the temperature to b1, b1=20~80℃, preheat the time to c1, c1=5~20min, the distance between the coating blade and the substrate is d1, d1=0.1~0.3 mm, and the coating speed is e1, e1=0.10~10mm / s; The initial cryogenic electron transport layer was obtained; The initial low-temperature electron transport layer was placed in a constant temperature chamber for annealing. The temperature of the constant temperature chamber was f1, where f1 = 100~120℃, and the annealing time was g1, where g1 = 10~180min. A dense SnO2 film, i.e., the low-temperature electron transport layer, was obtained. Step 2, Preparation of a low-temperature perovskite layer: Based on the low-temperature electron transport layer, an initial low-temperature perovskite layer is prepared using perovskite ink as raw material and a screen printing process. An initial low-temperature perovskite layer was prepared by screen printing. The mesh count of the screen was h1, h1=300~500, the temperature was b2, b2=20~50℃, the printing pitch was d2, d2=0.5~1mm, the printing pressure was i1, i1=0.10~0.20MPa, and the printing speed was e2, e2=5~50cm / s. This yielded an initial low-temperature perovskite layer based on the low-temperature electron transport layer. The initial low-temperature perovskite layer was placed in a constant temperature oven for annealing. The annealing temperature was f2, f2 = 80~100℃, and the annealing time was g2, g2 = 1~10min, to obtain a perovskite film, i.e., a low-temperature perovskite layer. Step 3, Prepare the low-temperature electrode layer: An initial low-temperature electrode layer was prepared using a screen printing process based on a low-temperature perovskite layer and carbon electrode paste as raw material. The carbon electrode paste is transferred to the surface of a printing screen, and screen printing is performed on the low-temperature perovskite layer. The screen mesh number is h2, h2=150~250, the printing pitch is d3, d3=0.5~1mm, the printing pressure is i2, i2=0.10~0.20MPa, the printing speed is e3, e3=5~20cm / s, and the temperature is c2, c2=20~50℃, to obtain the initial low-temperature electrode layer. The initial low-temperature electrode layer was placed in a constant temperature oven for annealing. The annealing temperature was f3, f3 = 50~80℃, and the annealing time was g3, g3 = 5~20min, to obtain a low-temperature carbon electrode, i.e., a low-temperature electrode layer. Step 1, preparing the low-temperature electron transport layer, further includes: The preparation process of the SnO2 colloid and deionized water mixture is as follows: SnO2 colloid is placed in deionized water, the volume ratio of SnO2 colloid to deionized water is a1, a1=1:3~10, and ultrasonically dispersed for 20min to obtain the SnO2 colloid and deionized water mixture. Step 2, preparing the low-temperature perovskite layer, further includes: The perovskite raw material with the composition FAXMA1-XPbI3 was dissolved in methylamine acetate, heated to 100°C, stirred for 6 hours, and placed in an environment with a temperature of 0°C for 1 hour to obtain screen printing perovskite ink. Step 3, preparing the low-temperature electrode layer, further includes: The preparation process of carbon electrode slurry is as follows: graphite with a particle size of 5μm, carbon black with a particle size of 20nm, and hydroxyethyl cellulose with a viscosity of 50mPa·s are placed into a ball mill jar in sequence. The weight ratio of carbon black to graphite is a3, where a3 = 1:3~5. The mixture is heated to 100℃ until dehydration, and then terpineol is added. The mixture is ball milled for 3 hours to obtain carbon electrode slurry.

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