In-situ bulk passivation method and system for perovskite thin films and perovskite optoelectronic devices

Abstract

This invention relates to an in-situ bulk passivation method, system, and perovskite optoelectronic device for perovskite thin films. The method includes the following steps: S100, obtaining a substrate and a perovskite precursor solution; S200, coating the perovskite precursor solution onto the substrate to form a wet film; during the coating process or in the early stage of drying and crystallization of the wet film, blowing a gas atmosphere containing an active passivating agent onto the surface of the wet film. This invention, by blowing out an inert gas containing a passivating agent, suppresses the formation of defects in the perovskite film during its initial formation stage, achieving in-situ bulk passivation of the perovskite thin film. This improves the efficiency and long-term stability of large-area perovskite photovoltaic modules. This method also avoids subsequent separate interface modification processes for the perovskite, reducing production costs and increasing production efficiency, providing strong support for the commercial production of perovskite solar cells.

Description

Technical Field

[0001] This invention relates to the field of perovskite solar cell technology, and in particular to an in-situ bulk phase passivation method, system, and perovskite optoelectronic device for perovskite thin films. Background Technology

[0002] Solar cells are one of the main methods of utilizing solar energy. Their basic principle is photovoltaic technology, which uses the photovoltaic effect to convert light energy into electrical energy. It has advantages such as being clean and pollution-free, environmentally friendly, providing high-quality energy, and being safe, making it highly promising for future market applications.

[0003] The development of solar cells has been rapid. Third-generation thin-film solar cells, represented by perovskite solar cells (PSCs), offer advantages such as low cost, simple fabrication processes, and excellent photoelectric performance. However, their commercial application still faces some challenges. Because perovskite is an ionic crystal with a relatively soft structure, the production process of large-area perovskite photovoltaic modules, which is primarily carried out in air, is affected by trace amounts of moisture in the air. This can accelerate perovskite crystallization, leading to poor crystal quality. Furthermore, oxygen in the air can oxidize I₂. - become Ions form I vacancy defects. Furthermore, during annealing in air, FA, I, and H2O molecules in the air form hydrogen bonds, increasing the formation of FA and I deficiency defects. These defects accelerate the decomposition of perovskite and induce the generation of more inactive phases, significantly reducing the efficiency and stability of perovskite photovoltaic modules (PPMs). Summary of the Invention

[0004] To address the aforementioned shortcomings, this invention proposes an in-situ bulk passivation method, system, and perovskite optoelectronic device for perovskite thin films. This invention provides a system that integrates an air knife to purge the passivating agent atmosphere within a slot coating apparatus. By blowing inert gas containing the passivating agent from the air knife, the formation of defects in the perovskite film is suppressed in the early stages of film formation, achieving in-situ bulk passivation of the perovskite thin film, thereby improving the efficiency and long-term stability of perovskite photopolymer particles (PPMs). Furthermore, this method avoids the need for subsequent separate interface modification processes on the perovskite, reducing production costs and increasing production efficiency, providing strong support for the commercial production of perovskite solar cells.

[0005] The technical solution adopted in this invention is an in-situ bulk phase passivation method for perovskite thin films. The method includes the following steps: S100, obtaining a substrate and a perovskite precursor solution; S200, coating the perovskite precursor solution on the substrate to form a wet film, and during the coating process or in the early stage of drying and crystallization of the wet film, blowing a gas atmosphere containing an active passivating agent onto the surface of the wet film.

[0006] Preferably, the active passivating agent in S200 includes at least one of volatile salts or organic amines.

[0007] Preferably, the process of coating the perovskite precursor solution on the substrate in step S200 specifically includes: using slot coating to coat the perovskite precursor solution on the substrate in an air atmosphere with a relative humidity of 10% to 50%.

[0008] The present invention also provides an in-situ bulk phase passivation system for perovskite thin films, used to implement the above-described in-situ bulk phase passivation method for perovskite thin films, comprising:

[0009] Slot coating die head, used to coat perovskite precursor solution onto substrate to form wet film;

[0010] A passivating agent atmosphere supply system for providing a gaseous atmosphere containing an active passivating agent;

[0011] An integrated air knife module is disposed adjacent to the slit coating die head, and its air inlet is connected to the output end of the passivating agent atmosphere supply system, for blowing the gas atmosphere onto the surface of the wet film.

[0012] Preferably, the passivating agent atmosphere supply system includes a passivating agent source, which includes at least one of a solid passivating agent evaporation source, a liquid passivating agent vaporization device, or a reactive gas source.

[0013] Preferably, the passivating agent atmosphere supply system further includes:

[0014] Carrier gas source, which provides inert carrier gas;

[0015] A mixing chamber that mixes the gases output from the passivating agent source and the carrier gas source to form a gaseous atmosphere of a predetermined concentration of active passivating agent.

[0016] Preferably, the integrated air knife module is located behind the slit coating die head, and the horizontal distance between the integrated air knife module and the slit coating die head is 10mm to 50mm.

[0017] Preferably, the angle between the air outlet of the integrated air knife module and the substrate is 15 degrees to 165 degrees, and the width of the air outlet is 0.1 mm to 10 mm.

[0018] Preferred options also include:

[0019] A computer control system is used to coordinate the control of the coating parameters of the slit coating die, the supply parameters of the passivating agent atmosphere supply system, and the purging parameters of the integrated air knife module.

[0020] The present invention also provides a perovskite optoelectronic device, which is prepared by the above-mentioned in-situ bulk phase passivation method of perovskite thin film, or prepared by the above-mentioned in-situ bulk phase passivation system of perovskite thin film.

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

[0022] 1. True in-situ bulk phase passivation: The passivating agent is directly introduced through air knife blowing during the drying and crystallization process of the perovskite wet film, which can penetrate deep into the film to effectively passivate defects inside the grains and grain boundaries, resulting in a more thorough and uniform passivation effect.

[0023] 2. Simplified and integrated process: The coating, drying and passivation processes are integrated into one step, reducing the additional steps of traditional subsequent passivation treatment, improving production efficiency, reducing process complexity and the risk of damage to the film due to post-processing.

[0024] 3. Precise and controllable: By precisely controlling the concentration, flow rate, air knife purging angle, pressure, and substrate temperature of the passivating agent atmosphere, the penetration depth and concentration of the passivating agent in the film can be finely controlled, thus optimizing the passivation effect.

[0025] 4. Compatibility and Innovation: This invention innovatively integrates existing slot coating and air knife drying technologies, and for the first time uses an air knife to purge an atmosphere of active passivating agents, making it highly compatible with large-area, large-scale production processes.

[0026] 5. Improve device performance and stability: This method is expected to produce high-quality perovskite films with lower and more uniform defect density, thereby achieving higher photoelectric conversion efficiency (PCE) and significantly improved long-term device stability (such as lifetime under MPPT test). Attached Figure Description

[0027] The present invention will now be described in detail with reference to the embodiments and accompanying drawings, wherein:

[0028] Figure 1 This is a flowchart of the in-situ bulk phase passivation method for perovskite thin films;

[0029] Figure 2 This is a schematic diagram of a slot coating combined with in-situ bulk phase passivation equipment;

[0030] Figure 3 This is a comparison curve of the current-voltage performance of perovskite solar cells;

[0031] Figure 4 This is a graph showing the operational stability of a perovskite solar cell. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0033] In one embodiment, an in-situ bulk phase passivation method for perovskite thin films is described in [reference needed]. Figure 1 The method includes the following steps:

[0034] S100. Obtain the substrate and the perovskite precursor solution. The substrate is a commonly used carrier substrate in the manufacture of perovskite optoelectronic devices, such as, but not limited to, a glass substrate covered with a transparent conductive oxide (such as ITO or FTO), on which a hole transport layer or an electron transport layer may have been pre-prepared. The perovskite precursor solution can be a solution system containing reactants such as a lead source and organic ammonium salts.

[0035] S200: The perovskite precursor solution is coated onto the substrate to form a wet film. During the coating process or in the early stages of drying and crystallization of the wet film, a gas atmosphere containing an active passivating agent is blown onto the surface of the wet film. In this step, the perovskite precursor solution is first applied to the surface of the substrate through a coating process to form a uniform wet film. The coating process can be slot coating suitable for large-area production, or other wet film formation technologies such as spin coating, blade coating, and spray coating.

[0036] In this embodiment, while the coating process is being carried out, or in the early stage after the coating is completed and the wet film begins to dry and crystallize (i.e., the kinetic window period when the solvent has not completely evaporated, perovskite crystal nuclei have begun to form but the long-range ordered crystal structure has not yet been established), a gas atmosphere containing an active passivating agent is blown onto the surface of the wet film.

[0037] The gaseous atmosphere of the active passivating agent is formed by the active passivating agent in a carrier gas. The active passivating agent refers to a substance with volatility and capable of chemically interacting with perovskite precursor components or intermediate phases. The gaseous atmosphere is delivered to the wet film surface by purging (e.g., via an air knife, nozzle, or other device) and covers the area above it.

[0038] In the early stages of drying and crystallization of the wet film, a large amount of solvent, mobile ionic precursors, and forming crystal nuclei still exist within the film layer. At this time, the active passivating agent molecules, due to their gas-phase characteristics, can rapidly and uniformly diffuse and penetrate into the interior of the wet film, rather than remaining only on the surface. These passivating agent molecules can interact with defect precursors generated during perovskite crystallization (such as uncoordinated lead ions, halogen vacancies, and organic cation vacancies) or metastable grain boundaries. For example, passivating agent molecules can fill ionic vacancies or passivate these highly active defect sites through coordination, bonding, etc., thereby suppressing the formation of bulk defects (including intragranular defects and grain boundary defects) at the source of crystal growth.

[0039] Currently, the interface defect passivation strategies developed in the field of perovskite solar cells are mainly carried out after perovskite film formation. Commonly used methods include spin-coating post-treatment, liquid-phase immersion, or steam treatment. However, since the perovskite film has already formed, these methods can only passivate defects on the surface of the perovskite and are difficult to diffuse into the interior of the perovskite. This makes it impossible to accurately and effectively passivate bulk defects inside the perovskite film. Furthermore, the post-treatment passivation step increases the process complexity, and the passivation solvent may also damage the already formed perovskite film. Another technology uses solution-based bulk passivation, which directly incorporates the passivating agent into the perovskite precursor solution. However, this may interfere with the normal crystallization of the perovskite, leading to a decrease in film quality.

[0040] Active passivating agents penetrate the interior of the film while it is still "wet" and structurally open, enabling uniform and effective passivation of defects from the bulk phase to near the surface, overcoming the limitation of post-treatment methods that can only treat surface defects. The passivation process is highly integrated with film formation and drying processes in terms of time and space, simplifying the process flow and avoiding the increased process complexity, solvent erosion of the formed film, and unfriendly conditions for large-area production that might result from subsequent separate passivation treatments. By intervening in and suppressing defect generation from the early stages of crystallization kinetics, it is beneficial to grow perovskite films with higher crystal quality and lower defect density, laying a crucial material foundation for the final fabrication of high-performance, high-stability perovskite optoelectronic devices.

[0041] In one embodiment, the active passivating agent in S200 includes at least one of volatile salts and organic amines.

[0042] Volatile salts are ionic compounds that can sublimate into vapor at process temperatures. A key characteristic is that their molecules or ionic units can directly participate in the construction or modification of the perovskite lattice. For example, they can contain the same organic cations (such as methylammonium ions or formamidinium ions) or halide anions as the target perovskite material, or they can contain larger organic cations with steric hindrance effects or specific functional groups (such as phenylethylamine ions). In the gas phase, the molecules or ions of these salts can diffuse into the wet film, directly reducing the density of point or planar defects within the crystal by replenishing missing lattice components or occupying and stabilizing grain boundary / surface sites.

[0043] Organic amines are small-molecule organic amine compounds that are volatile. Their mechanism of action differs from that of salts, primarily relying on their Lewis base properties and high reactivity. After permeating into the wet film from the gas phase, organic amine molecules can coordinate or chemically react with perovskite precursors or intermediate phases (especially unreacted lead halide species). This interaction can regulate crystallization kinetics, promoting more ordered crystal nucleation and growth, thereby spontaneously reducing bulk defects caused by non-stoichiometric or rapid crystallization during the crystallization process.

[0044] Both volatile salts and organic amines possess sufficient vapor pressure under mild conditions, allowing them to be effectively carried by a carrier gas and form a uniform atmosphere. This ensures their efficient transport and penetration into the wet film, fulfilling the prerequisite for "in-situ bulk phase" action. The chemical nature of these two types of substances determines their ability to engage in targeted and beneficial interactions with the perovskite system (such as ion replenishment, coordination regulation, and defect state passivation), achieving the goal of suppressing bulk defects through different pathways.

[0045] In one embodiment, the process of coating the perovskite precursor solution on the substrate in step S200 specifically includes: using slot coating to coat the perovskite precursor solution on the substrate in an air atmosphere with a relative humidity of 10% to 50%.

[0046] Slot coating is a precise, quantitative solution deposition technique that uses a coating die with precise slits to coat a precursor solution onto a moving substrate at a uniform thickness. The process characteristics of slot coating, such as linear coating, minimal edge effects, and high material utilization, provide a stable, continuous, and large-area wet film substrate for subsequent simultaneous purging and passivation, ensuring the consistency and controllability of the passivator atmosphere conditions.

[0047] The humidity range for the coating process is defined. A lower humidity limit (not less than 10%) helps regulate the initial drying kinetics and solvent evaporation rate of the perovskite precursor wet film, preventing macroscopic defects such as film cracking or pinholes caused by excessively rapid drying. It also provides a necessary time window for the active passivating agent vapor molecules to penetrate into the film. An upper humidity limit (not more than 50%) effectively suppresses the adverse chemical attack of excessive water molecules in the air on the perovskite precursor. Excessive moisture interferes with the normal crystallization process of perovskite, induces undesirable intermediate phases, and exacerbates intrinsic defects such as iodine ion loss.

[0048] In one embodiment, an in-situ bulk passivation system for perovskite thin films, used to implement the in-situ bulk passivation method for perovskite thin films in the above embodiments, includes: a slit coating die for coating a perovskite precursor solution onto a substrate to form a wet film; a passivating agent atmosphere supply system for providing a gas atmosphere containing an active passivating agent; and an integrated air knife module, disposed adjacent to the slit coating die, with its air inlet connected to the output end of the passivating agent atmosphere supply system, for blowing the gas atmosphere onto the surface of the wet film.

[0049] As the film-forming unit of the system, the slit coating die's core function is to receive and quantitatively deliver the perovskite precursor solution. Through its precise internal channels and slit outlet, the solution is uniformly coated onto the moving substrate surface, thereby forming a wet film with controllable thickness and good continuity. This die is the starting point of the entire process, providing the target medium for subsequent passivation.

[0050] The passivating agent atmosphere supply system, as the atmosphere generation and control unit of the system, has the core function of generating and delivering a gaseous atmosphere containing active passivating agents. The system converts solid or liquid active passivating agents into a gaseous phase through physical or chemical methods (such as heating and evaporation, carrier gas carrying, gas mixing, etc.), and fully mixes them with carrier gases (such as N2, Ar) to form a uniform passivating atmosphere flow with controllable concentration, temperature and flow rate.

[0051] The integrated air knife module, serving as the atmosphere application and distribution unit of the system, is a key component for achieving both "in-situ" and "purging" processes. This module is spatially adjacent to the slot coating die, typically located behind it along the substrate travel direction. Its air inlet is directly connected to the output of the passivating agent atmosphere supply system via piping, thereby receiving the prepared passivating atmosphere. The air knife module can also be internally designed with specific airflow channels, such as those containing a flow divider grid. Its function is to accelerate and shape the incoming passivating atmosphere into a uniform, stable laminar or slotted airflow, and precisely purge it from its outlet to the adjacent wet film surface.

[0052] See Figure 2By tightly integrating two functional modules—coating and passivation atmosphere application—a seamless transition and instantaneous switching between "wet film formation" and "atmosphere application" is achieved. This minimizes the ineffective waiting time between the wet film's exposure to the environment and its passivation process, firmly locking the critical kinetic window of "early drying and crystallization" within the process control range, creating optimal equipment conditions for in-situ passivation. An atmosphere is generated through a dedicated passivator atmosphere supply system and directionally and uniformly swept by an integrated air knife module, ensuring that active passivator molecules are delivered to the target area (wet film surface) in a highly efficient, low-loss, and highly targeted manner. This design avoids unnecessary diffusion and waste of the passivator in an open environment, improves raw material utilization, and ensures the consistency of the passivator dosage per unit area of ​​the film.

[0053] In one embodiment, the passivating agent atmosphere supply system includes a passivating agent source, which includes at least one of a solid passivating agent evaporation source, a liquid passivating agent vaporization device, or a reactive gas source.

[0054] Solid passivating agent evaporation sources are designed for solid active passivating agent materials that can sublimate or evaporate at process temperatures, such as methylamine hydroiodate (MAI), phenylethyl ammonium iodide (PEAI), and phenylethyl ammonium chloride (PEACl). Their core function is to use a precisely temperature-controlled heating device to directly transform the solid material from a solid phase to a gas phase, thereby generating high-purity passivating agent vapor.

[0055] Liquid passivating agent vaporization devices are suitable for vaporizable liquid active passivating agents, such as amine salt solutions or certain low-volatility liquid precursors. Their core function is to efficiently vaporize or transform liquid materials into aerosols through physical methods such as atomization, flash evaporation, or bubbling carrier gas, and then mix them with the carrier gas to form a uniform atmosphere.

[0056] Reactive gas sources are suitable for active passivating agents that are already in a gaseous state at normal temperature and pressure, or stored in high-pressure cylinders, such as methylamine gas (CH3NH2) and hydrogen halide gas (HX). The core function is to provide a source of passivating agents already in a gaseous state, typically achieved through components such as pressure reducing valves and mass flow controllers, enabling precise metering and direct delivery of the gaseous passivating agent.

[0057] Regardless of whether the initial physical state of the target active passivating agent is solid, liquid, or gaseous, the system can be adapted by selecting the corresponding source device. This allows the system to seamlessly interface with and apply a wide variety of potential passivating agent materials, providing significant freedom of choice and scalability for process development and optimization. Each source device is specifically designed for the physical characteristics of its corresponding material form (e.g., temperature-controlled evaporation for solids, forced vaporization for liquids, and precise metering for gases), ensuring the efficiency and reliability of the conversion from raw materials of different forms to a stable and controllable gaseous atmosphere, thus guaranteeing the stability of the passivating agent atmosphere quality from the source.

[0058] In one embodiment, the passivating agent atmosphere supply system further includes: a carrier gas source that provides an inert carrier gas; and a mixing chamber that mixes the gases output from the passivating agent source and the carrier gas source to form a gaseous atmosphere of an active passivating agent at a predetermined concentration.

[0059] The carrier gas source provides an inert carrier gas, such as nitrogen (N2) or argon (Ar), which are chemically stable gases. The carrier gas plays a dual role in the system, acting as both a dilution medium and a transport power source. Its main function is to dilute and carry gaseous passivating agent molecules or vapors from the passivating agent source at a stable and controllable flow rate, forming a readily transportable and uniformly distributed gas mixture.

[0060] A mixing chamber is a container or pipe structure used to achieve uniform gas mixing. Its first input is connected to the output of a passivating agent source, and its second input is connected to the output of a carrier gas source. The core function of the mixing chamber is to receive and physically contain the gas flows from these two sources. Through its specific internal flow channel design (such as a static mixer or turbulent chamber), it promotes sufficient convection, diffusion, and homogenization of the passivating agent vapor (or gas) and the inert carrier gas, ultimately outputting a uniformly composed and stable "gas atmosphere containing active passivating agent." Furthermore, the concentration of the passivating agent in this atmosphere can be preset and adjusted according to process requirements.

[0061] By independently controlling the output of the passivating agent source (e.g., evaporation rate) and the carrier gas source (e.g., mass flow rate), and utilizing a mixing chamber for homogenization, the system can precisely and flexibly prepare passivating agent atmospheres of different preset concentrations. This provides a key technical means for optimizing the passivating agent dosage for different perovskite formulations or process stages, achieving fine control of the passivation effect. The inert carrier gas provides a stable and continuous flow medium, effectively avoiding the instability in delivery caused by concentration fluctuations or condensation of pure passivating agent vapor. The mixing chamber ensures that the atmosphere achieves a high degree of compositional uniformity in both space and time before entering the purge module, thereby guaranteeing that the atmosphere purged to different areas of the wet film has a consistent passivation capability, which is crucial for obtaining uniform film quality.

[0062] For passivating agent vapors that may be reactive or corrosive at high concentrations, dilution with an inert carrier gas can reduce operational risks and make the process safer. At the same time, a stable carrier gas flow also helps maintain pressure stability throughout the gas supply line and purging module, improving the long-term reliability of the system.

[0063] In one embodiment, the integrated air knife module is located behind the slot coating die, ensuring that the coating of the perovskite precursor solution on the substrate (performed by the slot coating die) is completed first as the first step, forming a fresh wet film. Subsequently, this wet film immediately enters the working area of ​​the integrated air knife module, which is already in place behind it, during the continuous movement of the substrate. This sequential spatial layout of "coating-blowing" is the physical basis for achieving instantaneous connection of processes.

[0064] The horizontal distance between the integrated air knife module and the slot coating die is 10mm to 50mm. This distance is set based on a balance between the drying and crystallization kinetics of the perovskite wet film and the effective action window of the passivating agent. The lower limit of the distance (not less than 10mm) ensures that the airflow from the air knife module will not directly interfere with the leveling and initial stability of the wet film that is still forming below the coating die, thus avoiding affecting the macroscopic uniformity of the coated film. The upper limit of the distance (not greater than 50mm) ensures that the wet film can be covered by the passivating agent atmosphere in a very short time and distance after its formation. This minimizes the ineffective delay between the wet film's exposure to the environment and its active passivation, precisely targeting the purging action at the most critical and brief kinetic stage of "early drying and crystallization," when the solvent in the wet film has just begun to evaporate and the crystal nuclei are about to form or have begun to form.

[0065] In one embodiment, the angle between the air outlet of the integrated air knife module and the substrate is 15° to 165°, which defines the direction of the purge airflow impacting the wet film. Different purge angles directly affect the ratio of the tangential to the normal components of the airflow on the wet film surface, thereby affecting the coverage of the atmosphere, residence time, shear force on the wet film surface, and the penetration behavior of passivating agent molecules.

[0066] The width of the air outlet ranges from 0.1 mm to 10 mm. This parameter defines the initial geometry of the purge airflow, and the outlet width directly determines the potential for linear density and velocity distribution of the airflow as it leaves the air knife. A narrower width (e.g., 0.1 mm) is beneficial for forming a high-speed, concentrated airflow, enhancing local mass and momentum transfer, and may be suitable for scenarios requiring high penetration or small-area precision processing. A wider width (e.g., 10 mm) is beneficial for forming a laminar airflow with wider coverage and more uniform velocity, suitable for large-area uniform processing and reducing the risk of film disturbance caused by airflow impact.

[0067] By adjusting the air outlet direction, angle (15°-165°), and width (0.1-10mm) of the air knife, different drying and passivation kinetic requirements can be met, ensuring that the passivating agent atmosphere is blown out uniformly.

[0068] In one embodiment, the in-situ bulk phase passivation system for perovskite thin films further includes: a computer control system for coordinating the coating parameters of the slit coating die, the supply parameters of the passivating agent atmosphere supply system, and the purging parameters of the integrated air knife module.

[0069] Coating parameters for the slit coating die include coating speed, solution flow rate, and die-to-substrate distance. Supply parameters for the passivator atmosphere supply system include passivator evaporation or vaporization temperature, carrier gas flow rate, and target concentration and temperature of the mixed atmosphere. Purging parameters for the integrated air knife module include purging gas pressure or flow rate and the angle of the air knife outlet.

[0070] By introducing the aforementioned computer control system, this embodiment integrates the physical functional modules into an intelligent, organic whole. The achievement of a purge atmosphere for the active passivating agent during the initial stage of wet film drying and crystallization highly depends on the precise matching of time and intensity among coating, atmosphere generation, and purging. Through programming, the computer control system ensures that coating completion, atmosphere generation at a specific concentration, and air knife purging are automatically and synchronously triggered and executed according to preset timing and conditions. This reliably and repeatedly locks the entire process within the optimal kinetic window during complex, rapid, continuous production, something difficult to achieve manually or independently.

[0071] The system eliminates the uncertainties of parameter setting and timing judgment caused by human operation. By embedding the validated optimal process formulation (a set of parameters) into the control program, the system can ensure a high degree of consistency across different batches and production times, greatly improving product quality stability and yield—essential conditions for large-scale production. The computer control system allows for the convenient storage and recall of different process formulations (i.e., different parameter combinations), enabling the system to quickly adapt to different perovskite material systems, passivating agent types, or product specifications. Simultaneously, it provides an efficient platform for iterative optimization of process parameters based on experimental data and lays the core architectural foundation for further integration with online film thickness, humidity, or spectral monitoring to achieve closed-loop feedback control.

[0072] Furthermore, the computer control system can also coordinate the control of substrate temperature and other parameters to achieve precise coordination of multiple parameters.

[0073] In one embodiment, the in-situ bulk phase passivation system for perovskite thin films further includes a precision flow and temperature control system, which includes a mass flow controller (MFC), a temperature controller, and valves for precisely controlling the concentration and flow rate of the passivating agent vapor and the temperature of the mixed gas.

[0074] Mass flow controllers (MFCs) are used for extremely precise measurement and closed-loop control of the mass flow rate of gases (including carrier gases and / or gaseous passivating agents), ensuring a constant and setpoint-compliant gas flow rate into the mixing chamber. Temperature controllers are used for precise temperature monitoring and regulation of components involved in phase change or temperature-sensitive processes (such as solid passivating agent evaporation sources, liquid passivating agent vaporization devices, mixing chambers, and delivery pipelines) to stabilize the evaporation or vaporization rate of the passivating agent and control the temperature of the final mixed atmosphere. Valves, as regulating and switching actuators for the gas flow path, work in conjunction with MFCs and other components under the command of the control system to regulate the gas flow rate or control the on / off state of the gas path.

[0075] By precisely controlling the evaporation / supply rate of the passivating agent source (controlled by temperature and valves) and the dilution flow rate of the carrier gas (controlled by MFC), the concentration of active components in the mixed gas can be accurately set and maintained stably. Through the cooperation of MFC and valves, the total flow rate or pressure of the mixed gas finally output to the integrated air knife module is precisely controlled. Temperature controllers regulate the temperature of relevant components to ensure a constant atmosphere temperature during delivery, preventing passivating agent condensation or changes in reactivity due to temperature fluctuations.

[0076] In one embodiment, a perovskite optoelectronic device is prepared using the in-situ bulk phase passivation method for perovskite thin films described in the above embodiments, or prepared using the in-situ bulk phase passivation system for perovskite thin films described in the above embodiments. Perovskite optoelectronic devices include inverted perovskite solar cells, conventional perovskite modules, all-calcium stacks, calcium-silicon stacks, perovskite-organic stacked devices, as well as perovskite light-emitting diodes and perovskite photodetectors.

[0077] In one specific embodiment, the in-situ bulk phase passivation method includes the following steps:

[0078] (1) Prepare a piece of indium tin oxide (ITO) transparent conductive glass and scribing it with a picosecond laser to form an independent conductive oxide substrate.

[0079] (2) The conductive glass substrate was cleaned in an ultrasonic cleaner using glass cleaning fluid, acetone and isopropanol respectively to remove impurities and residual organic matter from the glass surface.

[0080] (3) Use an oven to dry the conductive glass to remove residual organic solvents on the surface.

[0081] (4) Use UVO ultraviolet ozone generator or plasma cleaning machine to treat the surface of conductive glass to improve wettability.

[0082] (5) Prepare hole transport layer material by using scraping, slot coating or magnetron sputtering to prepare hole transport layer on conductive glass substrate and then anneal.

[0083] (6) Prepare a perovskite precursor solution and put it into a stirrer and stir it evenly.

[0084] (7) The perovskite precursor solution is coated on the hole transport layer by slit coating method. The passivator atmosphere supply system is started simultaneously to deliver the passivator vapor of the predetermined concentration to the integrated air knife module. The integrated air knife precisely blows out a uniform atmosphere carrying active passivator above the perovskite wet film, which promotes perovskite nucleation and achieves in-situ passivation of bulk phase defects. Then it is placed on a hot stage for annealing to promote perovskite crystal growth.

[0085] (8) An electron transport layer and a hole blocking layer are deposited on the perovskite light absorption layer by vacuum thermal evaporation.

[0086] (9) Use picosecond laser to scribing P2, laser etching the conductive oxide and other film layers above it, and provide a transmission channel for the positive and negative electrodes of the two adjacent sub-cells.

[0087] (10) A metal electrode is deposited by vacuum thermal evaporation, and the metal electrode is used to extract electron carriers.

[0088] (11) Use picosecond laser to scribing P3 lines to separate the sub-cells.

[0089] (12) Use P4 scribing to clean the edges and remove the residual impurities from P2 and P3 scribing.

[0090] (13) Use encapsulating glue to encapsulate the components to protect the component structure and improve stability.

[0091] In a more specific embodiment, the in-situ bulk phase passivation method includes the following steps:

[0092] 1. Using a picosecond laser to target a 5×5 cm area. 2 Indium tin oxide (ITO) or fluorinated tin dioxide (FTO) transparent conductive glass is scribed using a P1 process, and the bottom conductive oxide film is etched by laser to form independent conductive oxide substrates. The laser scribing frequency is selected from 50-500 kHz, the energy is selected from 20-100 μJ, the width is 80-300 μm, and the speed is 200 mm / s.

[0093] Preferably, the transparent conductive glass is made of ITO substrate, and a 10×10 cm substrate can be selected. 2 Or other suitable sizes and shapes, the P1 laser scribing frequency is 200 kHz, the energy is 50 μJ, and the width is 100 μm.

[0094] 2. Ultrasonic cleaning of the glass substrate, using the following cleaning reagents in sequence: conductive glass cleaning solution, deionized water, and organic solvent. The conductive glass substrate must be completely immersed in the liquid, and each cleaning reagent should be used for 20±5 minutes.

[0095] Preferably, the organic reagent used for ultrasonic cleaning is isopropanol or acetone, and the cleaning time is 20 min.

[0096] 3. Remove the cleaned conductive glass substrate and dry it in a drying oven at 70°C for 24 hours.

[0097] 4. Remove the dried conductive glass substrate and transfer it to a suitable cleaning device such as a UVO ultraviolet ozone generator to clean and activate the glass surface for 15 minutes.

[0098] Preferably, a plasma cleaner can be used for cleaning, which takes only 5 minutes.

[0099] 5. Prepare the hole transport layer solution by dissolving 1 mg of [4-(3,6-dimethyl-9H-carbazole-9-yl)butyl]phosphonic acid (i.e., Me-4PACz) in 1 mL of methanol:chloroform solvent (volume ratio 1:1), shaking thoroughly for 10 h, and then filtering.

[0100] The selected hole transport layer material can also be replaced with other suitable materials for the hole transport layer of inverted perovskite solar cells, such as PTAA, PETDOS:PSS, CuPc, poly-TPD, 2PACz, MeO-4PADBC, and nickel oxide. The selected hole transport layer solvent can also be replaced with other suitable materials for the hole transport layer, such as 2-ME and DMF.

[0101] 6. A hole transport layer is prepared using a slot coating method. The hole transport layer is coated in an air atmosphere with a relative humidity of 10-50%. First, the inlet pipe of the slot coater is cleaned with a blank solvent, and then 15-30 mL of the prepared hole transport layer solution is added. The conductive glass substrate to be coated is placed in the slot coater, adsorbed and fixed onto the platform. Surface dust is removed by air blowing. A series of parameters are set, including the substrate length, width, and thickness, the speed of the plunger pump and platform, and the distance between the die and the platform. Coating is started, and the die moves at a uniform linear speed from one end of the substrate to the other (some devices move the die, others move the platform), coating a uniformly wetted thin film onto the substrate.

[0102] Preferably, the relative humidity can be prepared within the range of approximately 25%, the amount of hole transport layer solution used per piece is 10 μL, the distance between the die head and the substrate is 100 μm, and the platform advance speed is 10 mm / s. Furthermore, the deposition method for the hole transport layer can also include other suitable methods such as spin coating (small area, organic hole layer), magnetron sputtering, blade coating, inkjet printing, and atomic layer deposition.

[0103] Taking magnetron sputtering of nickel oxide as an example, the conductive glass substrate is removed and transferred to the magnetron sputtering system to deposit a thin nickel oxide film. The system pressure is... Pa. A small flow of oxygen can be introduced during sputtering to improve the composition of the nickel oxide film. The substrate can be moderately heated throughout the process. The thickness of the nickel oxide is monitored by a crystal oscillator and a film thickness gauge. The deposition thickness is approximately 20 nm.

[0104] 7. Transfer the substrate coated with the hole transport layer to the hot stage and anneal it on the hot stage at 100°C for 10 min.

[0105] 8. Configure Rb 0.05 Cs 0.05 MA 0.1 FA 0.8 The PbI3 perovskite precursor solution was prepared by dissolving 0.5071 g of lead iodide, 0.09 g of methylamine hydroiodate, 0.09 g of formamidinium hydroiodate, 0.0143 g of cesium iodide, and 0.0143 g of rubidium iodide in 1 mL of a mixed solvent of 2-ME and DMSO. The solution was shaken thoroughly for 10 h and then filtered.

[0106] The selected perovskite components can be replaced or added with other suitable materials such as methylamine hydroiodate, formamidinium hydroiodate, rubidium iodide, lead iodide, and lead bromide, as well as various combinations thereof, and the molar ratios of various components can be appropriately adjusted. Similarly, the solvent for the selected perovskite precursor solution can be replaced or added with other suitable reagents such as DMF, DMSO, and DMPU, as well as their combinations, and the volume ratios of various reagents can be adjusted to obtain perovskite light-absorbing layers with different band gaps and properties.

[0107] 9. A perovskite layer is prepared using a slot coating method. The perovskite layer is coated in an air atmosphere with a relative humidity of 10-50%. First, the plunger pump, die, and inlet pipeline are cleaned with DMF solvent. Then, the conductive glass substrate to be coated is placed on the slot coating machine, and dust on the glass surface is removed by air blowing. The substrate is then adsorbed and fixed onto the coating platform. A series of parameters are set, including the substrate length, width, and thickness, the movement speed of the plunger pump and platform, and the distance between the die and platform. Coating is then started, and the die moves linearly from one end of the substrate to the other at a uniform speed, coating a uniformly wetted film onto the substrate. Simultaneously, the passivating agent atmosphere supply system is started, delivering a predetermined concentration of passivating agent vapor to the integrated air knife module. The integrated air knife precisely blows a uniform atmosphere carrying the active passivating agent above the perovskite wet film. The passivating agent selected in this invention must have a certain degree of volatility, including volatile salts (such as MAI, FAI, PEAI, PEACl, etc.) and organic amines (such as methylamine, ethylamine gas, etc.). The passivating agent penetrates directly into the membrane during the initial stage of wet film drying and interacts with the perovskite precursor, intermediate phase or grain boundary (such as filling vacancies, forming complexes, and regulating crystallization kinetics) to achieve in-situ passivation of bulk phase defects.

[0108] Preferably, the relative humidity is around 20%, the amount of perovskite precursor solution used per piece can be 20 μL, the distance between the die head and the substrate is 100 μm, and the platform advance speed is 10 mm / s. The passivating agent vapor can be a mixture of F-PEACl / N2 gas.

[0109] 10. Transfer the substrate coated with the hole transport layer and perovskite precursor solution to a hot stage, anneal it on a hot stage at 70°C for 1 min, and then quickly transfer it to a hot stage at 120°C for annealing for 10 min to form a uniform, dense perovskite film with low bulk defect density.

[0110] 11. Deposit the electron transport layer. The electron transport layer material can be C. 60 PCBM ([6,6]-phenyl-C) 61 methyl butyrate), titanium dioxide, zinc oxide, and tin dioxide, etc., C 60 PCBM can be deposited using vacuum thermal evaporation (equipment vacuum level is 10). -4 Up to 10 -5 Methods such as spin coating or blade coating; titanium dioxide, zinc oxide, etc., can be applied by magnetron sputtering (equipment with a vacuum degree of 10 Pa). -4 Up to 10 -5 Tin dioxide (Pa) can be deposited using atomic layer deposition (ALD). The deposition rate can be controlled between 0.005 and 0.02 nm / s, and the deposition thickness can be selected appropriately between 20 and 60 nm.

[0111] Preferably, the electron transport layer can be deposited using a vacuum thermal evaporation method. The equipment vacuum level is 2 × 10⁻⁶. -4 Pa. The electron transport layer material is C. 60 The evaporation current was 40 A, the deposition rate was 0.01 nm / s, and the deposition thickness was 30 nm.

[0112] 12. Deposit hole-blocking layer material. Vacuum thermal evaporation can be used (the equipment vacuum level can reach 1×10⁻⁶). -4 Pa to 5×10 -4 Within the Pa range, suitable materials such as BCP or ALD can be deposited to deposit tin dioxide. The deposition rate can be selected within the range of 0.001-0.003 nm / s, and the deposition thickness can be selected between 6-7 nm. A layer of LiF or other suitable materials can also be deposited on top of the hole-blocking layer as a buffer layer using a suitable method.

[0113] Preferably, the hole-blocking layer material, copper bath (BCP), is deposited using a vacuum thermal evaporation method, with a vacuum level of 2 × 10⁻⁶. -4 Pa. Evaporation temperature was 220-240℃, evaporation voltage was 2.2-3.5 V, deposition rate was 0.002 nm / s, and deposition thickness was 6.5 nm.

[0114] 13. Picosecond lasers are used for P2 scribing, etching the conductive oxide and other layers above it to provide a transmission channel for the positive and negative electrodes of adjacent sub-cells. The laser scribing frequency can be selected within the range of 50-500 kHz, the energy within the range of 20-100 μJ, the width within the range of 40-300 μm, and the velocity within the range of 50-500 mm / s.

[0115] Preferably, the laser scribing frequency is 200 kHz, the energy is 48.5 μJ, the width is 50 μm, and the speed is 200 mm / s.

[0116] 14. Metal electrodes are deposited using a vacuum thermal evaporation method. The electrode material can be suitable conductive materials such as copper, silver, and gold. The vacuum level of the equipment can reach 1×10⁻⁶. -4 Pa to 5×10 -4 Within the Pa range, a suitable deposition rate can be selected from 0.02 to 0.1 nm / s, and a suitable deposition thickness can be selected from 50 to 200 nm. Other suitable deposition techniques, such as printing, can also be used.

[0117] Preferably, copper is deposited using a vacuum thermal evaporation method, with the electrode equipment having a vacuum level of 2×10⁻⁶. -4 Pa. The deposition rate was 0.05 nm / s, and the deposition thickness was 100 nm.

[0118] 15. Use a picosecond laser to perform P3 scribing to separate the sub-cells. The laser scribing frequency can be selected within the range of 50-500kHz, the energy within the range of 20-100 μJ, the width within the range of 40-300 μm, and the velocity within the range of 50-500 mm / s.

[0119] Preferably, the laser scribing frequency is 200 kHz, the energy is 48.5 μJ, the width is 50 μm, and the speed is 200 mm / s.

[0120] 16. Use P4 scribe lines for edge cleaning to remove residual impurities from P2 and P3 scribe lines and prevent short circuits. A suitable value can be selected within the range of 10-100 kHz for the frequency, 10-50 μJ for the energy, and 100-1000 mm / s for the velocity.

[0121] Preferably, the laser scribing frequency is 100 kHz, the energy is 20 μJ, the width is 100 μm, and the speed is 500 mm / s.

[0122] 17. Encapsulate the module using encapsulating adhesive. Apply a 1 cm wide butyl adhesive ring around the perimeter of the module, cover the thin film with a layer of polyolefin elastomer (POE) encapsulating film, top with a cover glass plate, and place it in a heat lamination machine. Set the temperature to 120℃ and the vacuum degree to 1×10⁻⁶. -2 Pa for 30 minutes to allow the butyl rubber to fully melt and adhere tightly to the surrounding area, achieving a good sealing effect.

[0123] In one embodiment, see Figure 3 Whether or not the in-situ bulk phase passivation method and system described in the above embodiments are used to prepare 10×10 cm 2 The photoelectric conversion efficiency of the perovskite solar cells was tested. Under standard sunlight intensity, the device efficiencies of the control group and the experimental group were 21.3% and 22.1% respectively (inverted structure), with the open circuit voltage increasing significantly from 8.6 volts to 9 volts.

[0124] In one embodiment, the operational stability of the perovskite solar cell prepared using the in-situ bulk phase passivation method and system described in the above embodiments is tested. See [link to documentation]. Figure 4The test conditions were as follows: after device packaging, under air conditions, 60℃, 50% relative humidity, and standard sunlight, the device efficiency was recorded every 50 hours. It can be observed that the device in the experimental group using in-situ bulk passivation showed almost no efficiency degradation after 1000 hours of operation, still maintaining more than 95% of the initial efficiency, while the device efficiency of the control group dropped rapidly, reaching only 70% of the initial efficiency after 1000 hours, indicating rapid aging.

[0125] This invention presents a slot-coating in-situ bulk passivation system based on an air knife-blown passivator atmosphere and a method for in-situ bulk passivation of perovskite films. The system innovatively integrates a passivator atmosphere supply system, a slot-coating die, and an air knife module, utilizing an air knife for the first time to purge an active passivator atmosphere (rather than just inert gas or air) onto the perovskite wet film. Through system integration innovation and deep process fusion, this method allows passivator molecules to directly penetrate and act on the interior of the film during the perovskite crystallization process, achieving in-situ bulk passivation and effectively reducing the density of bulk phase and grain boundary defects in the perovskite film. This method combines multiple processes into one, simplifying the process and overcoming the limitations of traditional surface passivation and solution-based bulk passivation. It can significantly improve the photoelectric conversion efficiency and long-term stability of perovskite optoelectronic devices and has good compatibility for large-area fabrication.

[0126] The above embodiments, modifications, and preferred solutions are merely illustrative of the present invention and are not intended to limit the implementation of this technology. It is neither necessary nor possible to exhaustively describe all possible implementations. For those skilled in the art, other variations or additions made based on the above description are still within the protection scope of this invention. Any modifications, alterations, and variations made by those skilled in the art using the disclosed technical content without departing from the spirit and scope of this invention are equivalent embodiments of the present invention; similarly, any modifications, alterations, and variations made to the various designs and embodiments of the present invention based on the essential technology of the present invention are still within the protection scope of this invention.

[0127] In the description of this specification, the use of terms such as "Embodiment 1," "this embodiment," or "in one embodiment" indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example; moreover, the specific features, structures, materials, or characteristics described may be combined in any appropriate manner in one or more embodiments or examples.

[0128] In the description of this specification, the terms "connection," "installation," "fixing," "setting," and "having" are interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0129] In the description of this specification, relational terms such as “first” and “second” are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0130] The above description of the embodiments is intended to enable those skilled in the art to understand and apply the technology of this invention. Those skilled in the art can easily make various modifications to these examples and apply the general principles described herein to other embodiments without creative effort. Therefore, this invention is not limited to the above embodiments. Modifications in the following situations should be within the scope of protection of this invention: ① New technical solutions implemented based on the technical solution of this invention and combined with existing common knowledge, where the technical effects of the new technical solution do not exceed the technical effects of this invention; ② Equivalent substitutions of some features of the technical solution of this invention using known technology, resulting in the same technical effects as those of this invention; ③ Extendable technical solutions based on the technical solution of this invention, where the substantive content of the extended technical solution does not exceed the technical solution of this invention; ④ Equivalent transformations made using the content of this specification and drawings, directly or indirectly applied to other related technical fields.

Claims

1. An in-situ bulk phase passivation method for perovskite thin films, characterized in that, The method includes the following steps: S100, Obtain the substrate and perovskite precursor solution; S200: Coating the perovskite precursor solution onto the substrate to form a wet film; during the coating process or in the early stage of drying and crystallization of the wet film, blowing a gas atmosphere containing an active passivating agent onto the surface of the wet film; the coating of the perovskite precursor solution onto the substrate in S200 includes: using slot coating, coating the perovskite precursor solution onto the substrate in an air atmosphere with a relative humidity of 10% to 50%; the active passivating agent in S200 includes at least one of volatile salts or organic amines. The coating process or the initial stage of drying and crystallization of the wet film specifically includes: a kinetic window period in which the solvent has not completely evaporated, perovskite crystal nuclei begin to form, but the long-range ordered crystal structure has not yet been established; the gaseous atmosphere of the active passivating agent is formed by the active passivating agent in the carrier gas, and the active passivating agent is a substance with volatility characteristics that can chemically interact with perovskite precursor components or intermediate phases.

2. An in-situ bulk phase passivation system for perovskite thin films, used to implement the in-situ bulk phase passivation method for perovskite thin films as described in claim 1, characterized in that, include: Slot coating die head, used to coat perovskite precursor solution onto substrate to form wet film; A passivating agent atmosphere supply system for providing a gaseous atmosphere containing an active passivating agent; An integrated air knife module is disposed adjacent to the slit coating die head, and its air inlet is connected to the output end of the passivating agent atmosphere supply system, for blowing the gas atmosphere onto the surface of the wet film.

3. The system according to claim 2, characterized in that, The passivating agent atmosphere supply system includes a passivating agent source, which includes at least one of a solid passivating agent evaporation source, a liquid passivating agent vaporization device, or a reactive gas source.

4. The system according to claim 3, characterized in that, The passivating agent atmosphere supply system also includes: Carrier gas source, which provides inert carrier gas; A mixing chamber that mixes the gases output from the passivating agent source and the carrier gas source to form a gaseous atmosphere of a predetermined concentration of active passivating agent.

5. The system according to any one of claims 2-4, characterized in that, The integrated air knife module is located behind the slit coating die head, and the horizontal distance between the integrated air knife module and the slit coating die head is 10mm to 50mm.

6. The system according to claim 5, characterized in that, The angle between the air outlet of the integrated air knife module and the substrate is 15 degrees to 165 degrees, and the width of the air outlet is 0.1 mm to 10 mm.

7. The system according to any one of claims 2-4 or 6, characterized in that, Also includes: A computer control system is used to coordinate the control of the coating parameters of the slit coating die, the supply parameters of the passivating agent atmosphere supply system, and the purging parameters of the integrated air knife module.

8. A perovskite optoelectronic device, characterized in that, It is prepared by the in-situ bulk phase passivation method of the perovskite thin film as described in claim 1, or by the in-situ bulk phase passivation system of the perovskite thin film as described in any one of claims 2-7.

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