METHOD FOR OBTAINING A HYBRID PEROVSKITE-BASED FILM FOR USE IN SOLAR CELLS, AND PRODUCT OBTAINED THE SAME

Abstract

The present invention relates to a method for obtaining hybrid perovskite-based films, comprising the steps of: (a) removing a fraction of said FTO layer from a glass plate or substrate coated with a transparent conductive layer of fluorine-doped tin oxide (FTO) using hydrochloric acid and zinc powder, forming a first absorbent layer; (b) washing the substrate obtained in step a) with soap, then washing with acetone to remove the soap, and immediately washing with isopropanol; (c) depositing a titanium isopropoxide solution onto the substrate washed in step b) to form a second layer; (d) depositing a titanium nanoparticle solution onto the substrate obtained in step c) above to form a third layer; (e) preparing a hybrid perovskite precursor solution (MAPbI3);(f) depositing a quantity of the hybrid perovskite precursor solution onto the substrate obtained in step d), after a certain time, a quantity of an antisolvent is deposited onto the substrate, forming a fourth layer or film of hybrid perovskite; (g) placing a Spiro-OMeTAD solution onto the substrate from step f) above to form a fifth layer or film; and, (h) depositing a metallic contact by vacuum evaporation onto the substrate from step g) above, forming a sixth layer.

Description

METHOD FOR OBTAINING A HYBRID PEROVSKITE-BASED FILM FOR USE IN SOLAR CELLS, AND PRODUCT OBTAINED THE SAME FIELD OF INVENTION The present invention relates to the techniques and principles used in Renewable Energy Engineering for the design, construction and implementation of technologies related to the use of renewable energy resources, such as the design and construction of solar panels or cells, and more specifically, it relates to a method for obtaining a hybrid perovskite-based film for use in the manufacture of solar cells, as well as the product obtained by said method. BACKGROUND OF THE INVENTION Today, solar panels are something everyone knows and are installed in most homes. You could say they're the queen of renewable energy. But everything evolves, and there are always innovations needed for the optimal functioning of these technologies, which make energy production an environmentally friendly process. These innovations are reflected in changes to the materials used. For example, in the case of solar cells, the material used to manufacture them is silicon. However, these silicon solar cells, besides being more expensive than other options, have very low efficiency—only about 20% of the sun's energy is converted into electricity.However, various scientific investigations have concluded that there may already be a substitute in the production of photovoltaic cells for solar cells that could correct these deficiencies and solve some of the limitations of silicon, namely: perovskite, another material. Rccfrnn / Lznz / E / YiAi is cheap, efficient, and more readily available than silicon (https: / / qruposinelec.com / que-es-la-perovskita / ) Hybrid perovskite (CH3NH3Pbl3) is composed of an inorganic and an organic part. The organic part can be an element or compound in the monovalent cation position of the crystal structure, such as methylammonium (CH3NH3 or MA), formamidinium (CH(NH2)2 or FA), cesium (Cs), or a binary or ternary combination of these. The inorganic part consists of the divalent cation positioned at the center of the octahedron of the crystal structure, such as lead (Pb2+) or tin (Sn2+). The monovalent anion (X-) within the hybrid perovskite structure is a halide (a Group VII element of the periodic table), such as chlorine (Cl), bromine (Br), iodine (I), or a combination thereof (CH3NH3Pbl3-YXY, where X = Cl or Br). Perovskite solar cells (PSCs) have demonstrated great potential as next-generation photovoltaic devices due to the spontaneous formation of a multilayer crystalline lattice [1], easy modulation of their energy gap (1.16–3.06 eV) [2], effective charge transport [3], and a manufacturing process based on low-cost solutions [2, 4–8]. Theoretically, PSCs are estimated to achieve efficiencies of up to 31% [9], and in practice, the best efficiencies have already reached up to 24.2%

[10] and 25.5%

[11] in small areas, 17.25% for mini-modules, and 11.7% for 703 cm² modules

[10] . Therefore, current research efforts are mainly focused on reducing toxicity [5,12,13], optimizing the manufacturing process [7,14], improving efficiency

[15] and stability [15-18] to explore the commercialization potential of these devices [7,12,14,17,19]. Regarding toxicity in PSCs, the replacement of the lead conductor (Pb) has always been considered the main challenge because complete replacement of the metal cation sacrifices the stability and efficiency of the device. To date, tin (Sn) is the most widely used element as a lead substitute, and theoretically, PSCs with Sn2+ can achieve efficiencies exceeding 24%

[20] . However, Sn2+ is highly susceptible to oxidation and quickly converts to Sn4+ upon contact with air, making these devices less stable than those containing lead [20,21]. Other sources of toxicity exist in PSCs, such as the solvents used for perovskite fabrication. Several studies have focused on the elimination of one of the primary solvents, chlorobenzene (CB)

[22] . This solvent is mainly used in the one-step deposition methodology as an antisolvent for the removal of dimethylformamide (DMF) from the precursor solution, leading to supersaturation of the solution and the subsequent formation of homogeneous perovskite thin films with large, compact grains. This process is commonly carried out in a controlled atmosphere (N2), where good reproducibility and efficiencies above 18% have been achieved, without mentioning the stability in a perovskite-based formulation (MAPbL)

[23] , or with reports of a lower deterioration rate in inorganic perovskites (CsPb2Br) with efficiencies up to 9.14%

[24] . The one-step methodology is a deposition technique with great potential for the fabrication of high-efficiency, low-cost PSCs [23,25-27]. Tongle Bu et al., 2018, demonstrated that ethyl acetate (EA) could replace CB as an antisolvent to produce high-quality perovskite films that exhibited a fast loading rate, low surface defect density, and an optimized interface with the transport layers, achieving high PSC efficiencies

[13] . However, in that work, it was not RCCfrnn / I 7P7 / B / YILI mention neither the atmospheric conditions under which the devices were made, nor the stability of the cells after storage under ambient conditions. Similarly, Jialiang Liu et al., 2019, demonstrated that it is possible to fabricate perovskite films with more compact and homogeneous grains from a mixture of AE-based antisolvent and isopropanol (IPA)

[28] . In this work, the PSCs were fabricated in a controlled atmosphere, achieving efficiencies of up to 18.98% with a reduction in hysteresis in the devices and with ambient stability of 90% of its initial value for 30 days. Despite the innovation of using a green antisolvent, the use of a glove chamber to control the fabrication conditions of the devices and ensure their high efficiency remains necessary. Another report also supports the use of acetate-based solvents as antisolvents for the fabrication of perovskite thin films, but under ambient conditions of 60–70% relative humidity (RH)

[29] . The high vapor pressure, low boiling point, and water miscibility of the antisolvent allow it to absorb ambient moisture or water from the precursor solution, thus protecting the perovskite formation in its intermediate phase and resulting in smaller, but compact, grains of methylammonium lead halides

[29] . It should be noted that the perovskite thin films obtained in this work were stable in air for only 15 days. On the other hand, it has been reported that adding additives to the antisolvent could improve the stability of the perovskite compound under ambient conditions. Ya-Han Wu et al., 2018, demonstrated that adding 4-tert-butylpyridine (tBP) to the CB antisolvent makes it possible to manufacture PSCs in a controlled atmosphere (N2) with efficiencies of up to 17.41%. Rccnnn / ιζηζ / E / γίΛΐ stable for 30 days

[30] . Perovskite grains (MAPbh) prepared under such conditions not only have a more homogeneous size, forming a compact and thin film, but also exhibit hydrophobic surface characteristics. Similarly, it is reported that the incorporation of tBP during the perovskite fabrication process modifies the work function of the obtained perovskite films, providing them with more p-type properties and favoring void extraction

[31] . The water miscibility of the antisolvent is a characteristic that gives the primary solvent of the mixture the ability to absorb moisture from the perovskite solution or surroundings in the early stages of film formation; likewise, it allows for adequate removal of the primary solvent from the solution to allow for proper film formation under ambient conditions.The hydrophobicity in perovskite films is a characteristic that is improved by the presence of tBP in the antisolvent, allowing a decrease in its deterioration rate and improving the surface physicochemical characteristics of the synthesized films

[32] . A couple of studies confirm that the use of the tBP additive in the CB antisolvent increases the short-circuit current density (Jsc), the fill factor (FF), and the open-circuit voltage (Voc) of the cells, due to the increased lifetime of the charge carriers and the passivation of trap states in hybrid perovskite compounds manufactured in a controlled atmosphere filled with an inert gas such as nitrogen [30,31]. In light of the above discussion, it is necessary to obtain PSCs that are efficient and stable in air, in addition to improving the stability of the perovskite compound under ambient conditions, so a good combination between the antisolvent and the additive is a very important issue to achieve this goal. Rccnnn / ιζηζ / E / γίΛΐ BRIEF DESCRIPTION OF THE INVENTION The present invention relates to a method for obtaining hybrid perovskite-based films, which comprises the steps of: (a) removing a fraction of said FTO layer from a glass plate or substrate coated with a transparent conductive layer of fluorine-doped tin oxide (FTO) using hydrochloric acid and zinc powder, forming a first absorbent layer; (b) washing the substrate obtained in step a) with soap, then washing with acetone to remove the soap, and immediately washing with isopropanol, wherein these washings are done without any intermediate steps; subsequently, the resulting substrate is air-dried and cleaned with UV / ozone;(c) depositing a solution of titanium isopropoxide (C12H28O4Ti) onto the washed substrate from step b), doing so by the one-step rotary deposition method at a speed of 2,800 rpm to 3,250 rpm for a time of at least 30s, then drying it at a temperature of 80 °C to 120 °C for a time not exceeding 10 min, and immediately heat-treating it at a temperature between 400 °C and 500 °C for a time not exceeding 30 min, forming a second compact layer of titanium oxide with a thickness of approximately 30 nm;(d) depositing a titanium nanoparticle solution onto the substrate obtained in step (c) above by means of the one-step rotary deposition method at a speed of 3,750 rpm to 4,250 rpm for a time of at least 30s, and subsequently heat-treating it at a temperature between 475 °C and 525 °C for a time not exceeding 30 min, forming a third mesoporous layer of titanium oxide, said third electron-carrying layer having a thickness of between 150 and 200 nm; (e) preparing a hybrid perovskite precursor solution (MAPbls) under ambient temperature and relative humidity conditions by mixing elements selected from the group comprising: methylammonium iodide (MAI), lead iodide (Pbk), and dimethyl sulfoxide (DMSO) in a 1:1:1 molar ratio (MAI:Pbl2:DMSO) with an amount of 1 ml of a solvent with continuous magnetic stirring at a speed of between 450 rpm and 600 rpm; Rccfrnn / Lznz / E / YiAi rpm for 1 h; (f) depositing an amount of approximately 70 pL of the hybrid perovskite precursor solution (MAPbh) onto the substrate obtained in step d) using the one-step rotational deposition method at a speed of 4,000 rpm to 6,000 rpm; when a time of approximately 7s has elapsed after the start of rotation, an amount of 100 μL to 140 pL of an antisolvent is deposited onto the substrate, forming a fourth layer or film of hybrid perovskite which is heat-treated at a temperature between 90 °C and 110 °C for a time not exceeding 5 min in an air atmosphere; (g) placing a Spiro-OMeTAD solution onto the substrate of step f) above by the one-step rotary deposition method at a speed of 2,250 rpm to 2,750 rpm for a time not exceeding 30s inside a controlled atmosphere glove chamber to form a fifth layer or film of Spiro-OMeTAD with a thickness of approximately 200 nm;and, (h) deposit by vacuum evaporation onto the substrate of the previous step g) in a high vacuum chamber of «2.6x10'5Torr a metallic contact, forming a sixth layer with a thickness of approximately 80 nm.; The antisolvent comprises a base solvent and an additive with hydrophobic properties, wherein the base solvent is ethyl acetate and the additive is 4-tert-butylpyridine (tBP). The antisolvent is prepared in a volume ratio of 98.5–99:11.5 of base solvent and additive, respectively. In a further aspect of the present invention, hybrid perovskite films obtained in accordance with the method described above are also provided, which have the following advantages: - stability under relative humidity conditions of around 60% and atmospheric environment; Rccnnn / ιζηζ / E / γίΛΐ - the increase in hydrophobicity of the synthesized films that gives rise to the decrease in the deterioration rate of the solar cells prepared with them; - the method for manufacturing highly reproducible photovoltaic devices; the elimination of the need for a controlled atmosphere for the synthesis of hybrid perovskite films, and therefore, the simplification of the manufacturing process; - the appropriate method for implementing less robust manufacturing conditions which potentially helps to decrease manufacturing process costs. In another aspect of the present invention, a use of hybrid perovskite films in the manufacture of solar cells is also provided. OBJECTS OF THE INVENTION Considering the disadvantages found in the prior art for the manufacture of perovskite-based solar cells, it is an object of the present invention to provide a method for obtaining hybrid perovskite (CHsNHsPbb) mirror-like films, wherein such films are used in the manufacture of solar cells. A further object of the present invention is to provide a method for obtaining hybrid perovskite-based films, giving the perovskite film better moisture resistance by having a greater possible amount of hydrophobic molecules. Another object of the present invention is to provide a method for obtaining hybrid perovskite-based films, wherein said films, when prepared under conditions Rccnnn / ιζηζ / E / γίΛΐ without encapsulation, show a maximum efficiency achieved of 18%, where the efficiencies of these PSCs retain more than 80% of the initial efficiency after 6 months of storage in darkness under ambient conditions. An additional object of the present invention is to provide a method for obtaining hybrid perovskite-based films, which can be carried out under ambient conditions of high relative humidity (RH ≥ 60%), using a mixture of ethyl acetate (EA) as an additive and 4-tert-butylpyridine (tBP) as an antisolvent, allowing the formation of mirror-like thin perovskite films. It remains a further object of the present invention to provide a method for obtaining hybrid perovskite-based films, which provide solar cells using these films with greater efficiency and stability under ambient conditions without the need for a glove chamber and / or controlled atmosphere. It is further an object of the present invention to provide hybrid perovskite films that are used in the manufacture of solar cells, providing them with greater efficiency and stability under ambient conditions without the need for a glove chamber and / or controlled atmosphere. The foregoing and other objects, as well as the features and advantages of the present invention, will become more obvious when the embodiments of the present invention are described in greater detail and with reference to the accompanying drawings, which, besides forming part of the present invention, provide further understanding of said embodiments but do not constitute a limitation of the present invention. Rccfrnn / ίζηζ / E / γίΛΐ drawings, the same numerical references generally represent equal or similar parts or steps. BRIEF DESCRIPTION OF THE FIGURES OF THE INVENTION The novel aspects that are considered characteristic of the present invention will be set forth in detail in the appended claims. However, the invention itself, both in terms of its organization and its method of operation, together with its other objects and advantages, will be better understood from the following detailed description of the embodiments of the present invention, when read in conjunction with the accompanying drawings, in which: Figure 1 contains photographs of four hybrid perovskite films prepared with different amounts of tBP in AE: 0 pmol, 34 pmol, 68 pmol and 102 pmolL Figure 2 is a schematic perspective view of a hybrid perovskite film (CH3NH3Pbl3) manufactured in full compliance with a particularly preferred embodiment of the method described and claimed in the present invention. Figure 3a shows X-ray diffraction (XRD) patterns of hybrid perovskite with 0, 8, 17 and 25 pmol of tBP as an additive in the antisolvent; D is the grain size value calculated according to the crystal plane (110); while Figure 3b shows Tauc plots and photoluminescence (PL) spectra (inset) of CH3NH3Pbl3 films with 0, 8, 17 and 25 pmol of tBP as an additive in the antisolvent ethyl acetate (EA). Rccfrnn / ίζηζ / E / γίΛΐ Figure 4 shows the Fourier transform infrared (FT-IR) spectra of CH3NH3Pbl3 films without antisolvent and with 0, 8, 17 and 25 pmol of tBP in AE, where figure a) is before and figure b) is after heat treatment at 100 °C for 2 minutes. Figure 5 shows the contact angle of a drop of distilled water on perovskite films with 0, 8, 17 and 25 pmol of tBP in AE. Figure 6a shows the top view of scanning electron microscopy (SEM) images of perovskite thin films with 0 pmol, 8 pmol, 17 pmol, and 25 pmol of tBP in the AE; while Figure 6b shows the grain size histograms of the images in Figure 6a. Figure 7a shows current-voltage density (JV) curves; the inset shows both the relative humidity (RH) and ambient temperature recorded during the preparation of the perovskite thin films; while Figure 7b shows the external quantum efficiency (EQE) spectra of the CH3NH3Pbl3-based solar cells fabricated with 0, 8, 17 and 25 pmol of tBP in AE as the antisolvent. Figure 8 shows the distribution of the quantity (frequency) of CH3NH3Pbl3 solar cells manufactured under ambient conditions of RH between 35% and 65% and ambient temperature of 23°C to 27°C with 0 and 8 pmol of tBP in the antisolvent AE; this study included the analysis of more than 80 samples of perovskite solar cells without the tBP additive (0 tBP) and more than 100 cells with tBP (8 pmol) in the antisolvent AE. Rccnnn / ιζηζ / E / γίΛΐ Figure 9 shows the normalized photovoltaic parameters as a function of storage time of solar cells based on CH3NH3Pbl3 with 0 pmol and 8 pmol of tBP in the antisolvent AE; the prepared cells were stored in the dark under ambient conditions of relative humidity (RH) between 35% and 65% and room temperature of 23 °C to 27 °C, where the normalized values ​​were averaged over 3 cell samples. Figure 10 shows the efficiencies of the perovskite solar cells, which were prepared by the 1-step process with AE as an antisolvent and tBP as an AE additive, as a function of relative humidity and ambient temperature. DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for obtaining hybrid perovskite (CH3NH3Pbl3) films with hydrophobic qualities, which are used in the manufacture of solar cells, providing them with greater efficiency and stability in the environment, wherein said method was developed in accordance with a particularly preferred, but not exclusive, embodiment of the present invention and comprises the steps of: a) removing from a glass plate or substrate covered with a transparent conductive layer of fluorine-doped tin oxide (FTO), a fraction of said FTO layer with hydrochloric acid and zinc powder, forming a first absorbent layer; b) wash the substrate obtained in step a) with soap, then wash with acetone to remove the soap and immediately wash with isopropanol, where these washes are preferably done in the order described and without any intermediate steps; subsequently, the substrate obtained is air dried and cleaned with UV / ozone; Rccnnn / ιζηζ / E / γίΛΐ c) depositing a solution of titanium isopropoxide (Ci2H28O4Ti) onto the substrate washed in step b), doing so by the one-step rotary deposition method at a speed of 2,800 rpm to 3,250 rpm, preferably 3,000 rpm, for a time of at least 30s, and then drying it at a temperature of 80 °C to 120 °C, preferably 100 °C for a time not exceeding 10 min, and then immediately heat-treating it at a temperature between 400 °C and 500 °C, preferably 450 °C for a time not exceeding 30 min, forming a second compact layer of titanium oxide with a thickness of approximately 30 nm; d) depositing a titanium nanoparticle solution onto the substrate obtained in step c) by means of the one-step rotary deposition method at a speed of 3,750 rpm to 4,250 rpm, preferably 4,000 rpm, for a time of at least 30 s, and then heat-treating it at a temperature between 475 °C and 525 °C, preferably 500 °C for a time not exceeding 30 min, forming a third mesoporous layer of titanium oxide, this being an electron-carrying layer with a thickness of between 150 and 200 nm; e) preparing a hybrid perovskite precursor solution (MAPbh) under ambient temperature (23°C to 27°C) and relative humidity (35% to 65%) conditions by mixing the elements selected from the group comprising: methylammonium iodide (MAI), lead iodide (Pbl2), and dimethyl sulfoxide (DMSO) in a molar ratio of 1:1:1 (MAI:Pbl2:DMSO) with an amount of 1 ml of a solvent, herein preferred but not limited to dimethylformamide (DMF), with continuous magnetic stirring at a speed of between 450 rpm and 600 rpm for 1 h; f) depositing an amount of approximately 70 pL of the hybrid perovskite precursor solution (MAPbh) onto the substrate obtained in step d) using the one-step rotary deposition method at a speed of 4,000 rpm to 6,000 rpm, preferably 5,000 rpm; after a time of approximately 7 After the rotation has begun, an amount of 100 pL to 140 pL, preferably 120 pL, of an antisolvent is deposited on the substrate, which in the present invention is preferred, but not limited to, an antisolvent comprising a base solvent and an additive with hydrophobic properties, wherein said base solvent in the present invention is preferred, but not limited to, ethyl acetate which is miscible in water, since solvents selected from the group comprising methyl acetate, diethyl ether and propyl acetate can be used;Whereas the additive in the present invention is preferred, but not limited to, 4-tert-butylpyridine (tBP), since additives having a molecular structure similar to tBP can be employed, which are selected from the group comprising amino, hydroxyl, tertiary butyl and ethyl groups with hydrophobic characteristics, or additives of molecular structure and properties different from tBP which are selected from the group comprising methanol, isopropanol and N-methyl-2-pyrrolidone, which, although used as additives, none of them provide hydrophobic properties to the surface of the perovskite film, wherein the antisolvent is prepared in a volume ratio of 98.5-99:1-1.5 of AE:tBP, preferably a ratio of 98.75:1.25 at a distance of 2 to 4 cm from the substrate surface to the tip of the instrument used for depositing the antisolvent;forming a fourth layer or film of hybrid perovskite that is heat-treated at a temperature between 90 °C and 110 °C, preferably 100 °C, for a time not exceeding 5 min in an air atmosphere; g) depositing a Spiro-OMeTAD solution onto the substrate of step f) above by the one-step rotary deposition method at a speed of 2,250 rpm to 2,750 rpm, preferably 2,500 rpm for a time not exceeding 30 s inside a controlled atmosphere glove chamber, which may be N2, to form a fifth layer or film of Spiro-OMeTAD with a thickness of approximately 200 nm; and, Rccnnn / ιζηζ / E / γίΛΐ h) depositing by vacuum evaporation onto the substrate of the previous step g) in a high vacuum chamber of =2.6x10-5Torr a metallic contact, which, in the present invention, is preferably, but not limited to, gold (Au), forming a sixth layer with a thickness of approximately 80 nm. As can be seen from the steps described above, the present invention comprises the novel combination or mixture of the solvent with the additive for the preparation of hybrid perovskite films prepared under high humidity ambient conditions (RH ≥ 60%) by one-step rotational deposition methods, wherein said solvent and additive, as described above, in the present invention are preferably, but not limited to being ethyl acetate (EA) and 4-tert-butylpyridine (tBP), respectively. Although the prior art has reported the separate use of both AE and tBP in the preparation of perovskite films, combining them in the antisolvent used in the method of the present invention required a prior analysis of the polarity of each, the miscibility of anhydrous AE with tBP, and the crystallization kinetics of the hybrid perovskite. It was observed that the good miscibility of AE allows the presence of tBP on the surface of the hybrid perovskite films to protect them from ambient humidity. Meanwhile, the amount of tBP in the anhydrous AE controls the formation kinetics of the hybrid perovskite compound within the prepared films, directly impacting the efficiency of the solar cells fabricated with hybrid perovskite films. Rccnnn / ιζηζ / E / γίΛΐ In the perovskite precursor solution, the primary solvents are polar; the polarity of DMF is 6.4 and that of DMSO is 7.2. During the one-step perovskite film preparation process, an antisolvent is used to obtain high-quality films. The function of an antisolvent is to effectively remove the primary solvent (DMF) and moisture from the solution to allow for proper perovskite film formation. The polarity of the antisolvent must be lower than that of the primary solvents, as is the case with chlorobenzene GB (2.7) or ethyl acetate AE (4.3). Given their relatively low boiling points, both CB and AE evaporate completely after the perovskite films are heat-treated at 100 °C.To date, AE has been shown to be a good substitute for its more explored counterpart, chlorobenzene (CB), as an antisolvent

[13] for the manufacture of hybrid perovskite thin films under humidity conditions of between 60% and 70%, but with a stability of only about 15 days

[29] . On the other hand, the hydrophobic tBP molecules, which have a higher boiling point, can remain on the surface of perovskite films after heat treatment. The polarity of tBP (5.3) is lower than that of DMF and DMSO, making it suitable as part of the antisolvent mixture. However, the amount of remaining tBP molecules per unit surface area depends on its miscibility with the antisolvents CB or AE. Due to tBP's polarity, it is more miscible in AE (4.3) than in CB (2.7), thus providing a scientific basis for choosing the AE+tBP combination as the antisolvent for the formation of more hydrophobic perovskite films. Since the novel combination of AE and tBP has not been reported in the prior art, it is important to note that the amount of tBP in the antisolvent plays a crucial role in perovskite crystallization. If the amount is too small, it fails to protect the perovskite from moisture; whereas, if the amount is too large, the excess tBP inhibits perovskite formation. Rccnnn / ιζηζ / E / γίΛΐ Finally, the combination of AE and tBP for the formation of moisture-resistant and ambient-stable hybrid perovskite requires that AE be anhydrous, as mentioned above. AE has a low boiling point and is highly miscible in water; therefore, the AE used as the base solvent in the antisolvent of the present invention for perovskite film formation must be anhydrous to prevent it from becoming supersaturated with water during ambient storage (relative humidity <30%). One option for keeping AE free of excess water is the use of solvent desiccants, such as anhydrous sodium sulfate (Na₂SO₄), calcium chloride (CaCl₂), or magnesium sulfate (MgSO₄). Hybrid perovskite thin films can be produced from different combinations of the monovalent cation, for example: methylammonium (CH3NH3 or MA), formamidinium (CH(NH2)2 or FA), or cesium (Cs); or from the monovalent anion, for example: iodine (I), chlorine (Cl), or bromine (Br). In the present invention, the synthesis of hybrid perovskite thin films composed of methylammonium lead iodide (CH3NH3Pbl3 or MAPbl3) was carried out under ambient conditions by the one-step rotational deposition method, with the mixture of AE and tBP as the antisolvent. In an additional aspect, the present invention also relates to hybrid perovskite films obtained by the method described above, which have the following advantages: - stability under relative humidity conditions of around 60% and atmospheric environment; - the increase in hydrophobicity of the synthesized films that gives rise to the decrease in the deterioration rate of the solar cells prepared with them; Rccnnn / ιζηζ / E / γίΛΐ - the method for manufacturing highly reproducible photovoltaic devices; - the elimination of the need for a controlled atmosphere for the synthesis of hybrid perovskite films and, therefore, the simplification of the manufacturing process; - the appropriate method for implementing less robust manufacturing conditions which potentially helps to decrease manufacturing process costs. The innovative combination of AE+tBP improves the quality and homogeneity of hybrid perovskite films by increasing their hydrophobicity, allowing them to maintain their photovoltaic performance for more than 180 days. The reduced deterioration rate of these films will also benefit various optoelectronic devices that utilize hybrid perovskite films. The applications of hybrid perovskite films are not limited, but include potential applications in optoelectronic devices such as photovoltaics, light-emitting diodes (LEDs), resistive memories, and photodetectors (X-ray detectors), among others. In another aspect of the present invention, a use of hybrid perovskite films is provided, namely in the manufacture of solar cells, to which they provide better efficiency and stability under ambient conditions without the need for a glove chamber and / or controlled atmosphere. The present invention will be better understood from the following example, which is presented for illustrative purposes only, not as a limitation, to allow for a complete understanding of the embodiments of the present invention. This does not imply that other unillustrated embodiments do not exist and can be implemented based on the detailed description provided above. It is important to note that the data and results The experimental results obtained in the example described below are solely intended to provide the necessary elements to carry out the invention, and should not be considered as limiting its scope: Example The influence of the additive 4-tert-butylpyridine (tBP) on the antisolvent ethyl acetate (EA) was determined for the synthesis of thin films of hybrid perovskite composed of CH3NH3Pbl3, used in the fabrication of photovoltaic devices. The CH3NH3Pbl3 films were deposited by rotational deposition using a mixed antisolvent method with 0, 8, 17, and 25 pmol of tBP per 100 pL of EA. If the amount of tBP exceeds 35 pmol, the formation of the hybrid perovskite compound (CH3NH3Pbl3) is inhibited. Figure 1 of the accompanying drawings shows that when the tBP additive is at 34 pmol, the color of the perovskite film remains dark. When this amount is 69 pm, the film color is light brown, indicating a low percentage of perovskite in the film. If the amount of tBP continues to increase to 102 pmol, no more perovskite forms in the film. Figure 2 of the accompanying drawings shows a schematic view of a solar cell fabricated with a hybrid perovskite film (CH3NH3Pbl3). The fabrication method for this solar cell was as follows: Rccnnn / ιζηζ / E / γίΛΐ was used as a rigid base for the manufacture of the photovoltaic cells, a glass substrate covered by a thin layer of fluorine-doped tin oxide (FTO) pre-etched and washed; - Compact titanium oxide (c-TiO₂) thin films were prepared using a sol-gel process by mixing isopropanol, titanium isopropoxide, and hydrochloric acid (HCl); the resulting solution was deposited to form c-TiO₂ thin films by the spin deposition method, followed by heat treatment in air at 450 °C for 30 minutes; - The mesoporous TiO2 solution (mp-TiO2) was prepared using TiO2 paste (commercial paste) diluted in ethanol in a weight ratio of 1:5, which was deposited by the rotational deposition method onto the cTiO2 layer, followed by a heat treatment in air at 500 °C for 30 minutes; The perovskite solution was deposited under ambient conditions on top of the mp-T₂O₂ layer; as soon as the MAPbl3 solution covered the entire surface of mp-T₂O₂, the rotation equipment was activated at 5000 rpm for 20 seconds; 7 seconds after the rotation was activated, the mixture of the antisolvent AE with the additive tBP was deposited, where the resulting MAPbl3 film was heat-treated at 100 °C for 2 min to form the perovskite film; - In a glove chamber, the Spiro-OMeTAD solution was deposited on top of the perovskite layer by rotational deposition method at 2500 rpm for 30s; - Finally, the gold (Au) contact is thermally evaporated on the SpiroOMeTAD in a high vacuum chamber of =2.6x10-5 Torr. The XRD patterns of the perovskite films with 0, 8, 17, and 25 pmol of tBP confirm the formation of the CH3NH3Pbl3 crystalline phase by the strong peaks at 14.1° and 27°, corresponding to (110) and (220) crystal planes (see Figure 3a of the accompanying drawings) [33,34], as well as other crystallographic orientations at: 9.96° (112), 23.48° (211), 24.5° (202), 31.82° (310), and 40.56° (224)

[35] . It was noted that all the films of Perovskite samples formed with the tBP additive showed a decrease in the intensity of the main peak at 14.1° compared to the reference sample. The crystal size (D) of the samples, calculated from the (110) plane using the Scherrer equation

[36] , decreased with the amount of tBP, going from 24.3 nm for the reference sample to a range between 22 and 23.3 nm for those made with the additive (Figure 3a). The addition of tBP modified the optical absorption spectra of the perovskite films, including the energy gap values ​​(see Figure 3b in the accompanying drawings), which decreased slightly as the proportion of the additive increased. Furthermore, as shown in the inset in Figure 3b, the addition of the tBP additive resulted in an increase in the intensity of the photoluminescence (PL) signals from the perovskite samples. The increase in the PL signal is commonly associated with the decrease in non-radioactive recombination centers

[37] . The improvement in photoluminescence intensity could be attributed to a passivation effect resulting from the coupling of tBP to the perovskite film grains, as will be demonstrated by Fourier transform infrared (FT-IR) spectroscopy characterization. The effects of tBP addition on the surface chemistry of perovskite films can be observed using FTIR. Figure 4 of the accompanying drawings shows the FT-IR spectra of perovskite films prepared with or without the antisolvent (AE+tBP), before (see Figure 4a) and after heat treatment (see Figure 4b) at 100 °C for 2 min. The position and assignment of the bands in the spectra are summarized in Table 1. NH and CH stretching vibrations around 3183 and 2983 cm⁻¹[38,39] are present in all film samples, regardless of heat treatment and tBP addition, suggesting the presence of methylammonium ions (MA+ or CH₃NH₃+) in all perovskite samples. Furthermore, the Rccnnn / ιζηζ / E / γίΛΐ The intensity of the NH band increases with the amount of additive, indicating that the tBP molecules were retained on the surface of the perovskite films. Rccfrnn / ίζηζ / Ε / γίΛΐ Wavenumber (cm-1) Assignment Functional Group Ref. Compound 3183 NH3+, Vas Amine

[38] MA / tBP 3136 NH3+, Vs Amine

[38] MA / tBP 2983 CH, v Aliphatic

[39] 47) (pg MA 1750 C=O, v Aliphatic ester

[39] 77) (pg EA 1639 C=O, v Carbonyl

[39] 86) (pg DMF 1580 C=C, ring v Heterocyclic

[39] (pg 83) tBP 1467 NH3+, os Amine

[38] MA 1419 CH3, os Methyl

[38] MA 1020 S=O, V Sulfoxide

[39] (pg 86) DMSO 945 CN, v Primary Amine

[38] MA 911 H3C-NH3+, P Amine

[38] MA 820 CH, δ Heterocycle

[39] (pg 83) tBP Table 1. Infrared band assignments of CH3NH3Pbl3 films fabricated with AE and the mixture of AE with tBP as antisolvent. DMF and DMSO are identified by the bands at 1639 and 1020 cm1

[39] , respectively. Residual DMF is largely removed by heat treatment, confirming the effectiveness of DMF extraction by the antisolvent AE. However, the other solvent, DMSO, cannot be completely removed by heat treatment (Figure 4b), although the intensity of its band decreases with the amount of tBP. The high boiling points of DMSO and tBP, 189 °C and 196.5 °C, respectively, explain their presence on the surface of perovskite films and suggest the possibility of the formation of an intermediate adduct between Pbk-DMSO-tBP-MAl [32, 33, 40-42]. The formation of this adduct could slightly hinder crystal and grain growth, since the amount of tBP additive is small, 8 or 17 pmol in AE. A similar observation is suggested in references

[32] and

[40] with chlorobenzene as an antisolvent and tBP as an additive.Finally, perovskite films with 25 pmol of tBP show, as expected, a very strong vibration of the NH, C=C and NH bands of the Pbk-tBP or MA-tBP complex [32,38,39,43]. Furthermore, the presence of a hydrophobic tBP on the surface of the perovskite thin films should affect their surface wettability. Figure 5 of the accompanying drawings shows the contact angles of distilled water droplets on the perovskite films. The measurements indicate an increase in the contact angle with the addition of tBP, from 54.65° without tBP to 57.28°–59.83° with tBP. This confirms that the hydrophobicity of the perovskite films has increased with the addition of tBP. SEM micrographs of perovskite thin films with different tBP concentrations in the AE are shown in Figure 6a of the accompanying drawings, from which the grain size distribution for each sample was obtained (see Figure 6b of the accompanying drawings). The average grain size decreases as the amount of additive increases, from 238 nm (reference sample, 0 pmol tBP) to 181 nm (8 pmol tBP) and 170 nm (17 pmol tBP). Simultaneously, the grain size distribution narrows, and the average grain size values ​​increase. This suggests that a more homogeneous grain size distribution is achieved in the perovskite thin film by adding a small amount of tBP.A larger amount of the additive, such as 25 pmol, would reverse the effect, as seen in Figure 6b, possibly due to the formation of the compound Pbk-tBP identified by XRD analysis (see Figure 3a). Rccfrnn / ίζηζ / E / γίΛΐ Figure 7a of the accompanying drawings shows the best current density versus applied voltage (JV) curves of solar cells based on perovskite thin films prepared with 0, 8, 17, and 25 pmol of tBP in AE under ambient conditions at room temperature = 25 °C and relative humidity (RH) = 60%. The electrical parameters of the four types of PSCs are summarized in Table 2 with statistical values ​​from more than 15 samples of each of the fabricated devices. An increase in all photovoltaic parameters was observed, including open circuit voltage (Voc), short circuit current density (Jsc), fill factor (FF), and power conversion efficiency (PCE) of the devices with the addition of 8 or 17 pmol of tBP in AE: the average Voc of the devices improved from 0.97 V to 1.01 V, Jsc from 21.45 to 24.26 mA / cm2, FF from 0.65% to 0.71, leading to an increase in efficiency from 13.65 to 17.14%.For devices with 25 pmol of tBP, there is a decrease in both Voc and Jsc, which in turn causes a decrease in the form factor and efficiency, thus limiting the amount of tBP that can be added to the antisolvent AE. Table 2 highlights the low deviation of the photovoltaic data for devices with 8 and 17 pmol of tBP, suggesting high reproducibility of the perovskite films with the addition of a small amount of tBP to the antisolvent AE. Finally, the external quantum efficiency (EQE) spectra of the same cells from Figure 6a are shown in Figure 7b, indicating the same improvement in photovoltaic performance for the 8 pmol and 17 pmol tBP devices. Rccbnn / ιζηζ / E / γίΛΐ Voc(V) Jsc (mA / cm2) FF ( %) PCE ( %) AE 0.97 ± 0.02 (0.99) 21.45 ± 0.31 (21.65) 65.36 ± 0.46 (65.87) 13.65 ± 0.38 (13.93) tBP 8 pmol 1.01 ± 0.01 (1.02) 23.68 ± 0.30 (23.9) 71.49 ± 1.17 (72.84) 17.07 ± 0.35 (17.41) tBP 17 pmol 1.00 ± 0.01 (1.01) 24.26 ± 0.25 (24.54) 70.89 ± 0.29 (71.07) 17.14 + 0.20 (17.27) tBP 25 pmol 0.83 ± 0.06 (0.89) 18.13 ± 0.89 (19.05) 53.75 ± 2.95 (55.66) 8.02 ± 0.48 (8.53) Table 2. Photovoltaic parameters of solar cells based on CH3NH3Pbl3 with 0, 8, 17 and 25 pmol of tBP in the antisolvent AE, prepared at ~25 °C and RH-60%. Maximum values ​​in parentheses. Derivation data on 15 cell samples. To confirm the effect of adding tBP on improving solar cell performance, a larger number of samples were fabricated under the same conditions described above. Figure 8 of the accompanying drawings shows the four photovoltaic parameters of 111 devices fabricated with AE and 131 devices fabricated with AE + 8 pmol of tBP as antisolvents. From these data, it was confirmed that the photovoltaic performance of the PSCs was improved by using AE + tBP as an antisolvent; the average Voc value increased from 0.91 to 0.99 V, Jsc from 16.26 to 20.61 mA / cm², FF from 0.56 to 0.66, and the efficiency from 8.66 to 13.73%. Among 131 cells based on AE+8 pmol of tBP, more than 55% show efficiencies greater than 16%, confirming the reproducibility of the samples. The stability of our perovskite solar cells was monitored for 6 months. Figure 9 of the accompanying drawings shows the photovoltaic parameters normalized as a function of storage time for those prepared with AE and the mixture of AE with 8 pmol of tBP as antisolvents. All values ​​in Figure 9 were averages of 3 samples of each cell type. It was observed that the devices with AE + 8 pmol of tBP remained at approximately 80% of their initial efficiency after 180 days of storage, and those made with AE alone retained approximately 72% of their initial efficiency after the same storage period. The highest efficiency achieved was 18.04% in devices with 8 pmol of tBP in AE. It was also observed that, regardless of the use of tBP, the FF was most significantly affected during storage, followed by the Voc and Jsc. Figure 10 of the accompanying drawings shows the influence of ambient conditions, with a relative humidity (RH) of 35%–65% and an ambient temperature (T) of 23–27°C, on the 131 cell samples prepared with AE + 8 pmol of tBP. The most efficient devices were those fabricated under an RH of approximately 60% at a temperature between 25–27°C, while cell samples prepared at lower temperatures and RH showed lower efficiencies. Gong et al. consider a certain water content in the perovskite precursor solution beneficial for the formation of perovskite films with good optoelectronic properties

[44] . According to our results, it appears that both ambient temperature and relative humidity affect the photovoltaic performance of perovskite solar cells. The mechanism by which tBP is added to AE to improve photovoltaic performance is related to the initial stage of perovskite formation. As soon as AE and tBP are placed in the initial coating of rotating perovskite precursors, each performs its respective function: AE removes DMF and DMSO, and tBP (with the highest boiling point among all solvents) forms complexes with the ionic compound Pbk to reduce spontaneous perovskite formation after the removal of DMF and DMSO. Consequently, the addition of tBP results in smaller crystals and perovskite grains with a more uniform grain size distribution. Rccfrnn / ίζηζ / E / γίΛΐ uniform, leading to a more compact surface. A more compact morphology of the perovskite thin films should reduce current leakage and, as a result, increase the parallel resistance and FF, as observed in the present example. On the other hand, it was observed that tBP molecules remain on the perovskite surface after heat treatment. The presence of tBP is reported to make the perovskite surface more p-type, leading to energy level bending at the interface with Spiro-OMeTAD, thus favoring the hole extraction process

[31] , and explaining the improved Voc and Jsc of our PSCs. As can be seen from the above description, as well as in the cited example, the mixture of AE and tBP is an effective antisolvent for forming mirror-like perovskite thin films, thanks to its ability to extract the primary solvent and moisture from the hybrid perovskite precursor solution (MAPbh). A small amount of tBP in EA consistently improves all photovoltaic parameters of PSCs, from an average efficiency of 8.64% across 113 devices using only AE as the antisolvent to 13.64% in 131 cells using AE+tBP as the antisolvent. More than 55% of the latter show efficiencies exceeding 16%. The top-performing cell initially registers an efficiency of 17.41%, reaches a peak efficiency of 18.04%, and maintains over 80% of its initial efficiency after more than 180 days of storage under ambient conditions without encapsulation.The method proposed here opens up the possibility of manufacturing highly efficient and stable hybrid perovskite-based solar cells under ambient conditions without the need for a glove chamber and / or atmosphere. Rccfrnn / ίζηζ / Ε / γίΛΐ controlled. Although exemplary embodiments of the present invention have been described with reference to the drawings, it should be understood that these exemplary embodiments are merely illustrative and are not intended to limit the scope of the present invention. It is likely that a person skilled in the art could make various changes and modifications to these embodiments, but without departing from the true scope and spirit of the present invention, and such changes and modifications must be intended to be included within the scope of the present invention as set forth in the appended claims. In the particularly preferred modality described herein, it should be understood that the method for obtaining hybrid perovskite (CH3NH3Pbl3) based films with hydrophobic qualities can be implemented in other ways, so that such modality of the method is merely exemplary. A person skilled in the art may understand that, in addition to the mutual exclusion of features, any possible combination may be adopted to incorporate and combine all the features disclosed by the description (including the appended claims, abstract, and drawings) and all processes or units of any method or device disclosed as such. Unless expressly stated otherwise, each feature disclosed by this description (including the appended claims, abstract, and drawings) may be replaced by an alternative feature that provides the same, equivalent, or similar purpose. Furthermore, a person skilled in the art may understand that, even though some of the embodiments described herein comprise some features included in other embodiments, rather than other features, combinations of features from different embodiments are considered to fall within the scope of the present invention and Rccnnn / ιζηζ / E / γίΛΐ form different modalities. For example, in the claims, in which any of the modalities for which protection is sought can be used in various combinations. References in the description to a modality or modalities indicate that the described modality may include a particular aspect, feature, structure, or characteristic, but not all modalities necessarily include that aspect, feature, structure, or characteristic. Furthermore, such phrases may, but do not necessarily, refer to the same modality mentioned elsewhere in the specification. Moreover, when a particular aspect, feature, structure, or characteristic is described in relation to a modality, it is within the knowledge of a person skilled in the art to affect or connect that aspect, feature, structure, or characteristic with other modalities, whether explicitly described or not. In other words, any element or characteristic may be combined with any other element or characteristic in different modalities, unless there is an obvious or inherent incompatibility, or it is specifically excluded. As such, an invention has been disclosed in terms of preferred embodiments thereof that fulfill each and every object of the present invention, as set forth above, and provide a method for obtaining hybrid perovskite (CH3NH3Pbl3) films with hydrophobic qualities. Of course, those skilled in the art may contemplate various changes, modifications, and alterations to the teachings of the present invention, but without departing from its intended spirit and scope. It is intended that the present invention be limited only by the terms of the appended claims. Rccfrnn / Lznz / E / YiAi The terminology used herein is solely for the purpose of describing particular or preferred embodiments and is not intended to limit the invention. As described herein, the singular forms a, an, and the are intended to include the plural forms as well, unless the context clearly indicates otherwise. It shall be further understood that the terms comprise and / or comprising, when described in this specification, specify the presence of stated features, whole numbers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more additional features, whole numbers, steps, operations, elements, components, and / or groups thereof. As described herein, the term and / or includes any and all combinations of one or more of the associated enumerated elements.Throughout the description, unless explicitly stated otherwise, the word understand and variations such as includes or that includes shall be understood to imply the inclusion of the stated elements, but not the exclusion of any other element. The use of the words first, second, and third does not imply any sequence. These words can be understood as a noun. The phrase "one or more" is easily understood by someone knowledgeable in the subject, particularly when read in the context of its use. As the person skilled in the subject will also understand, all language such as up to, at least, greater than, less than, more than, or over, and the like, includes the number mentioned, and these terms refer to ranges that may be further divided into subranges. For ranges of integers, the term approximately may include one or two integers greater than and / or less than a given integer at each end of the range. Unless otherwise stated herein, the term Rccfrnn / ίζηζ / E / γίΛΐ approximately intends to include values ​​and ranges close to the mentioned range that are equivalent in terms of the functionality of the composition, or modality. Claims may be drafted to exclude any optional elements. As such, this statement is intended to serve as a basis for precedent regarding the use of exclusive terminology, such as solely, only, and the like, in connection with the mention of claim elements or the use of a negative limitation. The terms preferably, preferred, prefer, optionally, may, and similar terms are used to indicate that a referenced element, condition, or step is an optional (not required) feature of the invention. In summary, although the preceding detailed description of the present invention has referred to certain embodiments of the method for obtaining hybrid perovskite (CH3NH3Pbl3) films with hydrophobic qualities, it should be emphasized that numerous modifications to these embodiments are possible, but without departing from the true scope of the present invention, such that the characteristics described in the aforementioned embodiments, shown in the figures and claimed in the claims chapter, as well as the characteristics of different embodiments not described herein, may be used individually or in any arbitrary combination for the realization of the present invention.Therefore, it should be understood that the embodiments of the present invention are merely illustrative and are not intended to limit the scope of the present invention except as provided in the prior art and the appended claims. Rccfrnn / Lznz / E / YiAi BIBLIOGRAPHIC REFERENCES [1] Y. Wei, P. Audebert, L. 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Claims

1. A method for obtaining hybrid perovskite-based films, characterized in that it comprises the steps of: a) removing from a glass plate or substrate coated with a transparent conductive layer of fluorine-doped tin oxide (FTO) a fraction of said FTO layer with hydrochloric acid and zinc powder, forming a first absorbent layer; b) washing the substrate obtained in step a) with soap, then washing with acetone to remove the soap, and immediately washing with isopropanol, wherein these washings are done without any intermediate steps; subsequently, the resulting substrate is air-dried and cleaned with UV / ozone;c) depositing a solution of titanium isopropoxide (C12H28O4Ti) onto the substrate washed in step b), doing so by the one-step rotary deposition method at a speed of 2,800 rpm to 3,250 rpm for a time of at least 30s, then drying it at a temperature of 80 °C to 120 °C for no more than 10 min, and immediately heat treating it at a temperature between 400 °C and 500 °C for no more than 30 min, forming a second compact layer of titanium oxide with a thickness of approximately 30 nm;d) depositing a titanium nanoparticle solution onto the substrate obtained in step c) above by means of the one-step rotary deposition method at a speed of 3,750 rpm to 4,250 rpm for a time of at least 30s, and subsequently heat-treating it at a temperature between 475 °C and 525 °C for a time not exceeding 30 min, forming a third mesoporous layer of titanium oxide, said third electron-carrying layer having a thickness of between 150 and 200 nm; Rccfrnn / Lznz / E / YiAi e) prepare a hybrid perovskite precursor solution (MAPbh) under ambient temperature and relative humidity conditions by mixing elements selected from the group comprising: methylammonium iodide (MAI), lead iodide (Pbk) and dimethyl sulfoxide (DMSO) in a molar ratio of 1:1:1 (MAI:Pbl2:DMSO) with an amount of 1 ml of a solvent with continuous magnetic stirring at a speed of between 450 rpm and 600 rpm for 1 h;f) depositing an amount of approximately 70 pL of the hybrid perovskite precursor solution (MAPbh) onto the substrate obtained in step d) using the one-step rotary deposition method at a speed of 4,000 rpm to 6,000 rpm; when a time of approximately 7s has elapsed after the start of rotation, an amount of 100 pL to 140 pL of an antisolvent is deposited onto the substrate, forming a fourth layer or film of hybrid perovskite which is heat-treated at a temperature between 90 °C and 110 °C for a time not exceeding 5 min in an air atmosphere; g) place a Spiro-OMeTAD solution onto the substrate of step f) above by the one-step rotary deposition method at a speed of 2,250 rpm to 2,750 rpm for a time not exceeding 30s inside a controlled atmosphere glove chamber to form a fifth layer or film of Spiro-OMeTAD with a thickness of approximately 200 nm;and, h) deposit by vacuum evaporation onto the substrate of the previous step g) in a high vacuum chamber of =2.6x10-5 Torr a metallic contact, forming a sixth layer with a thickness of approximately 80 nm.; 2. The method according to claim 1, further characterized in that the solvent used in step e) is dimethylformamide (DMF). Rccfrnn / Lznz / E / YiAi 3. The method according to claim 1, further characterized in that the antisolvent is added in step f) in an amount of 120 µL and comprises a base solvent and an additive with hydrophobic properties. 4 - The method according to claim 3, further characterized in that the base solvent is selected from the group comprising ethyl acetate, methyl acetate, diethyl ether and propyl acetate.

5. The method according to claim 4, further characterized in that the base solvent is ethyl acetate. 6 - The method according to claim 3, further characterized in that the additive must have hydrophobic characteristics and is selected from the group comprising 4tert-butylpyridine (tBP), amino, hydroxyl, tert-butyl, ethyl groups.

7. The method according to claim 3, further characterized in that the additive is selected from the group comprising methanol, isopropanol and N-methyl-2-pyrrolidone.

8. The method according to claim 6, further characterized in that the additive is 4-tert-butylpyridine (tBP).

9. The method according to claims 3 to 8, further characterized in that the antisolvent is prepared in a volume ratio of 98.5-99:1-1.5 of base solvent and additive, respectively. Rccnnn / ιζηζ / E / γίΛΐ 10. The method according to claim 9, further characterized in that the antisolvent is prepared in a volume ratio of 98.75:1.25 of base solvent and additive, respectively. 11 - The method according to claim 1, further characterized in that the controlled atmosphere in step g) is nitrogen. 12 - The method according to claim 1, further characterized in that the metallic contact used in step h) is gold (Au).

13. Use of a hybrid perovskite film obtained in accordance with the method of the preceding claims, wherein said use is in the manufacture of solar cells, providing them with the following advantages: - stability under relative humidity conditions of around 60% and atmospheric environment; - the increase in the hydrophobicity of the synthesized films which gives rise to the decrease in the deterioration rate of the solar cells prepared with them; - the method for manufacturing highly reproducible photovoltaic devices; - the elimination of the need to have a controlled atmosphere for the synthesis of the hybrid perovskite films, and therefore, the simplification of the manufacturing process; - the method suitable for implementing less robust manufacturing conditions which potentially helps to decrease the costs of the manufacturing process.