Photoelectric conversion device

Abstract

A photoelectric conversion device (100) comprises: a translucent first substrate (1); a plurality of first power generation units (3) disposed on a main surface (1a) of the first substrate (1) at distances from each other; a second substrate (2) disposed so as to face the first substrate (1) across the plurality of first power generation units (3); a sealing member (6); and a first layer (8). The plurality of first power generation units (3) each comprise a first photoelectric conversion layer containing a perovskite compound. The plurality of first power generation units (3) are disposed in a sealed space (SP) formed between the first substrate (1) and the second substrate (2) by the sealing member (6). The first layer (8) is disposed in the sealed space (SP) at a distance from the plurality of first power generation units (3) in the thickness direction of the first substrate (1). The first layer (8) is a visible-light reflection layer of which the light reflectance for at least specific wavelengths, in the wavelength range of visible light, is higher than the light reflectance of the second substrate (2) for the specific wavelengths, or is a second photoelectric conversion layer containing a perovskite compound.

Description

Photoelectric conversion devices

[0001] The present disclosure relates to photoelectric conversion devices.

[0002] There are known photoelectric conversion devices that can be applied to building materials for houses, vehicles, etc. For example, Patent Document 1 discloses a glass building material that uses a silicon solar cell.

[0003] Meanwhile, in recent years, development of perovskite solar cells using perovskite compounds has been progressing as a new solar cell to replace silicon solar cells.

[0004] JP 2023-107850 A

[0005] Photovoltaic conversion devices used in building materials are required to have high durability so that they do not deteriorate even when installed outdoors for a long period of time, and also to generate more electricity.

[0006] An object of the present disclosure is to solve the above-mentioned problems and to provide a photoelectric conversion device that can improve durability and increase the amount of power generation.

[0007] The photoelectric conversion device according to the present disclosure comprises: a light-transmitting first substrate; a plurality of first power generation units arranged on a main surface of the first substrate at a distance from each other; a second substrate arranged to face the first substrate across the plurality of first power generation units; a sealing member; and a first layer, wherein each of the plurality of first power generation units comprises a first photoelectric conversion layer containing a perovskite compound; the plurality of first power generation units are arranged in a sealed space formed between the first substrate and the second substrate by the sealing member; and the first layer is arranged in the sealed space at a distance from the plurality of first power generation units in a thickness direction of the first substrate; and the first layer is either a visible light reflective layer having a reflectance for light of at least some wavelengths in a wavelength range of visible light higher than the reflectance of light of the second substrate for the at least some wavelengths, or a second photoelectric conversion layer containing a perovskite compound.

[0008] According to the present disclosure, it is possible to provide a photoelectric conversion device that can enhance durability and increase the amount of power generation.

[0009] 11 is a schematic top view of a photoelectric conversion device according to a first embodiment. It is a schematic end view taken along line II-II in FIG. 1 . It is a schematic enlarged end view of region P shown by the dashed line in FIG. 2 . It is a schematic end view taken along line IV-IV in FIG. 1 . It is a schematic enlarged end view of region Q shown by the dashed line in FIG. 2 . It is a flowchart showing an example of a manufacturing method of a photoelectric conversion device. It is an enlarged cross-sectional view schematically showing a photoelectric conversion device according to an example. It is a diagram showing measurement results of optical characteristics of a first structure in an example. It is a diagram showing measurement results of optical characteristics of another first structure in an example. It is a schematic end view of a photoelectric conversion device according to a second embodiment. It is a schematic enlarged end view of region R1 shown by the dashed line in FIG. 9 . It is a schematic end view of a photoelectric conversion device according to a second modification. It is a schematic enlarged end view of region R2 shown by the dashed line in FIG. 11 . It is a diagram illustrating the optical characteristics (spectral transmittance, spectral reflectance, and spectral absorptance) of a photoelectric conversion device according to a comparative example. It is a diagram illustrating the spectral absorptance of a photoelectric conversion device, a glass substrate, and a power generation layer according to a comparative example. FIG. 11 is an enlarged cross-sectional view schematically showing a photoelectric conversion device of Modification 3.

[0010] <Findings that Form the Basis of the Present Disclosure> The present inventors have conducted extensive research into the structure of a photoelectric conversion device that uses a perovskite solar cell, in particular into a structure that can be suitably applied to a window material.

[0011] The inventors first investigated the optical properties of perovskite solar cells and discovered the following. Perovskite solar cells primarily absorb, for example, visible light and convert it into electricity. When such perovskite solar cells are used as window materials, if a power generation unit made of perovskite solar cells is provided on the entire surface of the window, visible light is less likely to penetrate indoors. For this reason, for example, multiple power generation units may be arranged at a distance from each other on the window surface. This allows some of the visible light contained in sunlight to penetrate the area between adjacent power generation units and enter the indoors. However, this reduces the ratio of the total area (light-receiving area) of the power generation units to the window surface, and may result in an inability to obtain the desired amount of power generation.

[0012] However, perovskite solar cells can deteriorate due to reactions with water vapor and oxygen in the atmosphere, resulting in a decrease in conversion efficiency. For this reason, there is a need to improve the durability of perovskite solar cells, especially when they are used as building materials.

[0013] The present inventors have therefore discovered a structure in which multiple power generation units (perovskite solar cells) and a layer that reflects visible light or absorbs visible light and converts it into electricity (hereinafter referred to as the "first layer") are arranged within a sealed space sealed from the outside. In a photovoltaic device having such a structure, not only visible light incident on the power generation units from the light-receiving surface side but also a portion of visible light that transmits between adjacent power generation units can be used for power generation (photovoltaic conversion). This increases the amount of power generated. Furthermore, by arranging the power generation units and the first layer within a sealed space, the durability of the photovoltaic device can be improved. Specifically, this suppresses the decrease in conversion efficiency due to degradation of the perovskite compound caused by reaction with external air (oxygen, moisture, etc.) and the change in the optical properties of the first layer due to external air (moisture, etc.). Based on this novel finding, the present inventors have arrived at the following disclosure.

[0014] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. Note that the present disclosure is not limited to these embodiments. In addition, substantially identical components in the drawings are denoted by the same reference numerals, and duplicate explanations are omitted as appropriate. For illustrative purposes, the dimensions of each element in the drawings may be exaggerated and are not necessarily drawn to scale.

[0015] Furthermore, for the sake of convenience, the following uses terms indicating directions such as "up," "down," "right," "left," and "side," assuming a state of normal use, but this does not mean to limit the state of use of the photoelectric conversion device according to the present disclosure.

[0016] In the drawings described below, for reference, mutually orthogonal X-axis, Y-axis, and Z-axis are schematically shown. In the following description, when simply referring to the X direction, Y direction, or Z direction, it refers to the respective axial direction, and includes two opposite directions (for example, the −X direction and the +X direction).

[0017] In this specification, "visible light" refers to light with a wavelength of 300 nm to 800 nm. "Average absorptance of visible light" is the average absorptance in the wavelength range of 300 nm to 800 nm. "Average transmittance of visible light" is the average transmittance in the wavelength range of 300 nm to 800 nm.

[0018] First Embodiment The basic configuration of a photoelectric conversion device according to a first embodiment of the present disclosure will be described with reference to Figures 1 to 5. In the first embodiment, a visible light reflective layer is used as the first layer.

[0019] Fig. 1 is a schematic top view of a photoelectric conversion device according to this embodiment. Fig. 2 is a schematic end view taken along line II-II shown in Fig. 1. Fig. 3 is a schematic enlarged end view of region P shown in Fig. 2. Fig. 4 is a schematic end view taken along line IV-IV shown in Fig. 1. Fig. 5 is a schematic enlarged end view of region Q shown in Fig. 4.

[0020] As shown in Figures 1 to 5, the photoelectric conversion device 100 includes a first substrate 1 and a second substrate 2, a plurality of power generation units 3 including a photoelectric conversion layer, a pair of extraction electrodes 4 electrically connected to each of the plurality of power generation units 3, a sealing member 6, and a visible light reflective layer 8.

[0021] The photoelectric conversion device 100 can be applied to building materials such as windows, roofs, and exterior walls of buildings. The photoelectric conversion device 100 may be a building-material-integrated solar cell integrated with a building material. The photoelectric conversion device 100 can be installed, for example, so that the outer surface on the first substrate 1 side faces outdoors and the outer surface on the second substrate 2 side faces indoors. The photoelectric conversion device 100 may be a see-through device that can transmit visible light in the thickness direction.

[0022] In this embodiment, the first substrate 1 and the second substrate 2 face each other with the power generating unit 3 interposed therebetween. The sealing member 6 forms a space (sealed space) SP sealed from the outside between the first substrate 1 and the second substrate 2. The power generating unit 3 and the visible light reflective layer 8 are disposed in the sealed space SP.

[0023] The first substrate 1 and the second substrate 2 are, for example, glass substrates or resin substrates. The first substrate 1 is light-transmitting. This allows power generation using light incident on the power generation unit 3 from the first substrate 1 side. In this specification, "light-transmitting" means transparency to visible light. "Having light-transmitting" means, for example, that the transmittance of visible light is 50% or more, preferably 70% or more. The second substrate 2 may also be light-transmitting. This makes it possible to obtain a photoelectric conversion device 100 that is capable of transmitting visible light.

[0024] 1 to 5, the first substrate 1 and the second substrate 2 each have a roughly rectangular parallelepiped shape. In FIGS. 1 to 5, the direction corresponding to the thickness direction of the first substrate 1 of the photoelectric conversion device 100 is referred to as the "Z direction." In addition, directions perpendicular to each other in a plane perpendicular to the Z direction are referred to as the X direction and the Y direction. Here, for convenience, directions parallel to two adjacent sides of the rectangular main surface of the first substrate 1 are referred to as the X direction and the Y direction, respectively. Note that the shapes of these substrates are not limited to the examples shown in the drawings.

[0025] 2 to 5, the first substrate 1 and the second substrate 2 are arranged so that the main surface 1a of the first substrate 1 and the main surface 2a of the second substrate 2 face each other. These main surfaces 1a and 2a, together with the sealing member 6, define a sealed space SP. Light enters the photoelectric conversion device 100, for example, from the back surface 1b of the first substrate 1, which is opposite to the main surface 1a. In this specification, the back surface 1b of the first substrate 1 may be referred to as the "light-receiving surface."

[0026] The multiple power generation units 3 are arranged at intervals from one another on the main surface 1a of the first substrate 1. In the example shown in FIG. 1 , the multiple power generation units 3 are arranged at intervals from one another in the Y direction. Each power generation unit 3 is a solar cell element string in which multiple solar cell cells (perovskite solar cell cells) 31 are connected in series. Each power generation unit (each string) 3 is made up of multiple solar cell cells 31 arranged roughly in the X direction. The multiple power generation units 3 are connected in parallel by extraction electrodes 4.

[0027] 3 and 5 , each power generation unit 3 includes a stacked structure (hereinafter referred to as the "power generation layer") PV including a lower electrode layer 311, an upper electrode layer 313, and a photoelectric conversion layer 312 located between the lower electrode layer 311 and the upper electrode layer 313 in the Z direction. The lower electrode layer 311 is located between the photoelectric conversion layer 312 and the first substrate 1. The photoelectric conversion layer 312 contains a perovskite compound and is a layer that mainly absorbs visible light and converts it into electricity. The specific structures of the power generation layer PV and the solar cell 31 will be described later.

[0028] 5, the multiple power generation sections (solar cell element strings) 3 are arranged at a distance g from each other in the Y direction. The photoelectric conversion layers 312 and the upper electrode layers 313 of two adjacent power generation sections 3 are arranged at a distance g from each other in the Y direction. The lower electrode layer 311 extends in the Y direction across the multiple power generation sections 3. In other words, the lower electrodes of solar cells 31 located at the same position in the X direction are connected to each other. The lower electrode layers 311 of two adjacent power generation sections 3 may also be arranged at a distance g from each other.

[0029] When viewed along the Z direction, a photoelectric conversion layer 312 that easily absorbs visible light is not formed in a region r1 located between adjacent power generation units 3. A lower electrode layer 311 may be disposed in region r1, but the lower electrode layer 311 is a transparent electrode that is translucent. For this reason, region r1 transmits visible light more easily than region r2 in which the photoelectric conversion layer 312 is formed. In this specification, when viewed along the Z direction, in the first substrate 1 on which the power generation units 3 are provided, region r1 located between adjacent power generation units 3 is referred to as a "visible light transmitting region," and region r2 in which the power generation units 3 (photoelectric conversion layer 312) are located is referred to as a "visible light absorbing region."

[0030] The sealing member 6 prevents moisture and gas from entering the sealed space SP in which the power generation units 3 are located from the outside of the photovoltaic device 100. In this embodiment, the sealing member 6 is provided between the first substrate 1 and the second substrate 2 so as to surround the multiple power generation units 3 when viewed from the Z direction. When viewed from the Z direction, the sealing member 6 may extend in an annular shape along the periphery of the main surface 1a of the first substrate 1. Examples of materials that can be used for the sealing member 6 include rubber such as butyl rubber, thermoplastic resins such as ethylene-vinyl alcohol copolymer (EVOH), or combinations of these. The sealing member 6 may also include materials other than those listed above. For example, the sealing member 6 may further include a getter agent (gas absorbing layer). Furthermore, the sealing member 6 may include multiple types of sealing materials. The sealing member 6 may have a multilayer structure including multiple layers of different materials.

[0031] The extraction electrode 4 is, for example, an electrode having a lower specific resistance (electrical resistivity) than the electrode used in the power generation unit 3. The extraction electrode 4 may be a metal electrode. For example, a wire (tab wiring) made of a copper wire coated with solder may be used as the extraction electrode 4.

[0032] 1 , the extraction electrodes 4 include a first electrode 4A electrically connected to the solar cell 31 located on the leftmost side (−X side) of each power generation unit 3, and a second electrode 4B electrically connected to the rightmost side (+X side). One of the first electrode 4A and the second electrode 4B is a positive electrode, and the other is a negative electrode. Each of the first electrode 4A and the second electrode 4B may extend from the sealed space SP through the sealing member 6 to the outside of the sealing member 6.

[0033] The visible light reflective layer 8 is a layer whose reflectance for light of at least some wavelengths within the wavelength range of visible light is higher than the reflectance for light of the at least some wavelengths of the second substrate 2. The visible light reflective layer 8 reflects a portion of the visible light that is incident from the light-receiving surface 1b side and transmitted through the visible light transmission region r1 toward the power generation unit 3. A portion of the visible light reflected by the visible light reflective layer 8 is incident on the top surface of the power generation unit 3 (the surface facing the second substrate 2) and is absorbed into the power generation unit 3, and can be used for photoelectric conversion.

[0034] 3 and 5 , the visible light reflective layer 8 is disposed in the sealed space SP at a distance H in the Z direction from the power generation unit 3. In this example, the visible light reflective layer 8 is provided on the main surface 2a of the second substrate 2. In the sealed space SP, an intermediate layer 5 is interposed between the power generation unit 3 and the visible light reflective layer 8. The intermediate layer 5 may be, for example, a hollow layer or a resin layer. This prevents contact between the power generation layer PV containing a perovskite compound and the visible light reflective layer 8, thereby suppressing a decrease in conversion efficiency.

[0035] The visible light reflective layer 8 at least partially overlaps with the visible light transmitting region r1 when viewed along the Z direction. In the example shown, the visible light reflective layer 8 overlaps with the entire visible light transmitting region r1 when viewed along the Z direction. The visible light reflective layer 8 may be disposed over substantially the entire main surface 2a of the second substrate 2 in the sealed space SP.

[0036] In the example shown in FIG. 2 , the visible light reflective layer 8 is disposed only in the sealed space SP, and is not located between the second substrate 2 and the sealing member 6. In this example, when viewed along the Z direction, the main surface 2a of the second substrate 2 includes a first region a1 that overlaps the visible light reflective layer 8 and a second region a2 that is located outside the first region a1 and does not overlap the visible light reflective layer 8. The sealing member 6 is located in the second region a2. With this configuration, the entire visible light reflective layer 8 can be disposed in the sealed space SP, which more effectively suppresses changes in optical properties due to deterioration of the visible light reflective layer 8. Furthermore, because the visible light reflective layer 8 is not interposed between the sealing member 6 and the second substrate 2, it is possible to suppress a decrease in adhesion between the sealing member 6 and the second substrate 2.

[0037] The visible light reflective layer 8 may extend between the second substrate 2 and the sealing member 6. For example, the visible light reflective layer 8 may be formed over the entire main surface 2a of the second substrate 2. This eliminates the need for a patterning step for removing part of the visible light reflective layer 8 after the visible light reflective layer 8 is formed over the entire substrate surface. This therefore reduces the number of manufacturing steps and reduces manufacturing costs.

[0038] Each component of the photoelectric conversion device 100 will be described in more detail below.

[0039] (Visible Light Reflection Layer) The visible light reflection layer 8 may be composed of a single layer or may have a laminated structure. There are no particular limitations on the thickness of the visible light reflection layer 8, but it is, for example, 30 nm to 500 nm.

[0040] The visible light reflective layer 8 may be a layer that is transmissive to visible light (for example, having an average visible light transmittance of 5% or more). This allows a predetermined proportion of visible light to be transmitted in the thickness direction of the photoelectric conversion device 100, even when the visible light reflective layer 8 is formed on substantially the entire surface of the second substrate 2. Furthermore, by forming the visible light reflective layer 8 on substantially the entire surface of the second substrate 2, the design can be improved when viewed from indoors.

[0041] As an example, the visible light reflective layer 8 may be a filter layer configured to selectively transmit light in a specific wavelength range within the above wavelength range and reflect light of wavelengths other than the transmitted wavelength. The filter layer may be, for example, a dielectric multilayer film. Examples of materials for the filter layer include TiO ２ and SnO ２ Known inorganic or organic materials such as the above can be used.

[0042] The visible light reflective layer 8 may be a layer that selectively reflects light of a part of the wavelength range of 300 nm to 800 nm. For example, the reflectance of the visible light reflective layer 8 may be higher than the reflectance of the second substrate 2 in a part of the wavelength range of 300 nm to 800 nm. Alternatively, the reflectance of the visible light reflective layer 8 may be higher than the reflectance of the second substrate 2 over the entire wavelength range of 300 nm to 800 nm.

[0043] A metal layer with low light transmittance (or no light transmittance) may be used as the visible light reflective layer 8. In this case, the metal layer may be disposed so as to cover only a portion of the main surface 2a of the second substrate 2. For example, by forming slits or openings in the metal layer or by forming a plurality of island-shaped metal layers, it becomes possible for a portion of the visible light that has passed through the visible light transmitting region r1 to pass through a region of the second substrate 2 where no metal layer is formed and enter the indoors.

[0044] The visible light reflective layer 8 may be a layer having a higher reflectivity for visible light than for near-infrared light, thereby selectively reflecting light of wavelengths that are primarily absorbed by the power generation unit 3 out of the light incident on the visible light reflective layer 8 toward the power generation unit 3.

[0045] (Intermediate Layer) The intermediate layer 5 is, for example, a hollow layer. The hollow layer may be, for example, a nitrogen layer, an argon layer, or a krypton layer. Alternatively, the hollow layer may be an air layer filled with air having a lower oxygen concentration than the atmosphere. By lowering the oxygen concentration in the hollow layer, it is possible to more effectively suppress a decrease in conversion efficiency due to a reaction between the perovskite compound and oxygen.

[0046] The intermediate layer 5 may be a solid layer such as a resin layer. This can prevent fragments (e.g., glass) from falling off when the first substrate 1 or the second substrate 2 is broken. A resin layer with high adhesive strength may be used as the intermediate layer 5. A layer containing a thermoplastic resin may be used as the resin layer. The softening point of the thermoplastic resin may be, for example, 120°C or lower.

[0047] The intermediate layer 5 may be made of a resin such as ethylene-vinyl acetate copolymer (EVA), polyolefin (PO), or polyvinyl butyral (PVB).

[0048] The resin layer may be a layer that fills the area of ​​the sealed space SP where the power generating unit 3 and the extraction electrode 4 are not located. This makes it possible to more effectively prevent fragments (e.g., glass) from falling off when the substrate is broken.

[0049] 3 and 5 , each solar cell 31 includes a lower electrode formed in a lower electrode layer 311, an upper electrode formed in an upper electrode layer 313, and a photoelectric conversion unit formed in a photoelectric conversion layer 312. In this specification, in each power generation unit 3, the lower electrode layer 311 is a layer including a plurality of lower electrodes (lower electrodes of a plurality of solar cell cells 31). The upper electrode layer 313 is a layer including upper electrodes of a plurality of solar cell cells 31, and the photoelectric conversion layer 312 is a layer including photoelectric conversion units of a plurality of solar cell cells 31.

[0050] In each power generation unit 3, the upper electrode of one of two adjacent solar cell cells 31 is electrically connected to the lower electrode of the other solar cell 31, for example, in a hole formed in the photoelectric conversion layer 312. In this way, the multiple solar cell cells 31 that make up the power generation unit 3 are connected in series.

[0051] The photoelectric conversion layer 312 is a layer that converts absorbed light into electricity. The photoelectric conversion layer 312 includes, for example, a light absorption layer 312i. The photoelectric conversion layer 312 may further include an electron transport layer and / or a hole transport layer as necessary. In the example shown in FIG. 3 , the photoelectric conversion layer 312 is a stacked film including, from the first substrate 1 side, an n-type semiconductor layer (electron transport layer) 312n, an i-type semiconductor layer (light absorption layer) 312i, and a p-type semiconductor layer (hole transport layer) 312p. Note that the photoelectric conversion layer 312 is not limited to the example shown in the figure, and may also be a stacked film including, from the first substrate 1 side, a p-type semiconductor layer, an i-type semiconductor layer, and an n-type semiconductor layer.

[0052] The light absorbing layer 312i is a perovskite layer containing a perovskite compound (perovskite semiconductor) as a photoelectric conversion material. The perovskite compound has the chemical formula ABX ３ and structures having crystals similar thereto, where A is a monovalent cation, B is a divalent cation, and X is a halogen anion.

[0053] Both the lower electrode layer 311 and the upper electrode layer 313 are transparent conductive layers having light-transmitting properties. This allows visible light to be incident on both sides of the photoelectric conversion layer 312 (from the side on the lower electrode layer 311 side and the side on the upper electrode layer 313 side) and used for power generation. The lower electrode layer 311 and the upper electrode layer 313 are, for example, metal oxide layers having light-transmitting properties, such as indium tin oxide (ITO), indium zinc oxide (IZO), or fluorine-doped tin oxide (FTO) layers.

[0054] The power generation layer PV may include layers other than those described above. For example, a molybdenum oxide layer may be disposed between the p-type semiconductor layer and the upper electrode layer. This prevents damage to the p-type semiconductor layer when the upper electrode layer is formed on the p-type semiconductor layer.

[0055] (Method for Manufacturing Photoelectric Conversion Device) FIG. 6 is a flowchart showing an example of a method for manufacturing the photoelectric conversion device 100 (FIGS. 1 to 5) of this embodiment.

[0056] First, a first substrate is prepared having a power generation section (power generation layer) formed on its main surface. The lower electrode layer, photoelectric conversion layer, and upper electrode layer of the power generation section can each be formed by a known method such as coating or sputtering, and then patterned by laser processing or the like. After forming a laminate film that will become the power generation layer over the entire main surface of the first substrate, multiple power generation layers may be formed by removing portions of the laminate film by laser scribing or the like. In this case, the areas of the power generation section and the visible light transmission region can be adjusted by adjusting the area removed from the laminate film. Next, an extraction electrode electrically connected to the power generation section is formed on the first substrate. For example, the aforementioned tab wiring may be joined to the electrode of the power generation section using solder or the like.

[0057] A second substrate is also prepared, having a visible light reflective layer formed as a first layer on its main surface. The visible light reflective layer can be formed on the main surface of the second substrate by, for example, sputtering, vapor deposition, coating, printing, or the like. Alternatively, the second substrate may be a glass substrate having a reflective film (e.g., an Ag, Ti, or Sn film) that can function as a visible light reflective layer pre-formed on its main surface. If necessary, the visible light reflective layer may be patterned to remove a portion of the visible light reflective layer located in the area where the sealing member will be formed.

[0058] Next, the first substrate and the second substrate are arranged so that the power generation section formed on the first substrate faces the first layer (here, the visible light reflective layer) formed on the second substrate. A sealing member is then formed between the first and second substrates to seal the power generation section. An extraction electrode is disposed so as to penetrate the sealing member or extend to the outside through the gap between the sealing member and the first substrate. In this manner, a photoelectric conversion device is manufactured.

[0059] When a solid layer such as a resin layer is formed as the intermediate layer 5, a filler material serving as the intermediate layer may be disposed between the first and second substrates before or after forming the sealing member, and the first and second substrates may then be laminated. For example, a filler sheet containing polyolefin may be used as the filler material. During lamination, the filler material dissolves under reduced pressure and wraps around the power generation section, bonding the first and second substrates together. Lamination reduces the likelihood of an air layer remaining around the power generation section, thereby suppressing the effect of air on the photoelectric conversion layer. An autoclave may be used instead of lamination. Furthermore, when a hollow layer (gas layer) is formed as the intermediate layer 5, lamination or other processes may not be necessary.

[0060] 1 to 5 , in the photoelectric conversion device 100 of this embodiment, a plurality of power generation units 3 and a first layer are arranged in the sealed space SP between the first substrate 1 and the second substrate 2, at a distance H in the thickness direction (Z direction) of the first substrate 1. The plurality of power generation units 3 are arranged at a distance from each other on the main surface 1a of the first substrate 1. Each power generation unit 3 has a photoelectric conversion layer 312 containing a perovskite compound. The first layer is a visible light reflective layer 8 whose reflectance for light of at least a portion of the wavelength range of 300 nm to 800 nm is higher than the reflectance for light of the second substrate.

[0061] With the above configuration, a portion of visible light incident on the light-receiving surface 1b of the photoelectric conversion device 100 is absorbed by the power generation unit 3 and converted into electricity, while the remaining portion is transmitted through the visible light transmission region r1 located between two adjacent power generation units 3. A portion of the transmitted light is reflected by the visible light reflective layer 8 and enters the power generation unit 3 from the side opposite the light-receiving surface 1b, where it can be used for photoelectric conversion. In this way, visible light that has transmitted through the visible light transmission region r1 can be used to generate additional power, thereby increasing the amount of power generated by the power generation unit 3 (see FIG. 7 ).

[0062] Furthermore, with the above configuration, the provision of the visible light reflecting layer 8 makes it difficult for visible light contained in sunlight incident on the light-receiving surface 1b to pass through the photoelectric conversion device 100. Furthermore, since the visible light reflecting layer 8 is disposed on the incident side of the second substrate 2, visible light is less likely to be absorbed by the second substrate 2. Therefore, the solar heat gain coefficient of the photoelectric conversion device 100 can be reduced.

[0063] Furthermore, with the above configuration, since the photoelectric conversion layer 312 is disposed in the sealed space SP, deterioration of the photoelectric conversion layer 312 due to a reaction between the perovskite compound and oxygen or moisture (water vapor) from the outside can be suppressed. Therefore, a decrease in conversion efficiency due to deterioration of the photoelectric conversion layer 312 can be suppressed. If the conversion efficiency decreases due to deterioration, the amount of visible light absorbed by the photoelectric conversion layer 312 that is converted into thermal energy increases, which may increase the amount of heat dissipated from the photoelectric conversion layer 312. In contrast, with the above configuration, an increase in the amount of heat dissipated due to deterioration of the photoelectric conversion layer 312 can be suppressed, thereby preventing an increase in the solar heat gain coefficient. Furthermore, since the visible light reflecting layer 8 is disposed in the sealed space SP, deterioration of the visible light reflecting layer 8 due to moisture and changes in its optical properties (reflection properties) can be suppressed. Therefore, a decrease in power generation due to deterioration of the visible light reflecting layer 8 can be suppressed.

[0064] Furthermore, with the above configuration, the power generation unit 3 and the first layer (here, the visible light reflective layer 8) are disposed at a distance H, which has the following advantages: Light reflected by the visible light reflective layer 8 is more likely to be incident on the surface of the power generation unit 3 opposite the light-receiving surface 1b (the upper surface of the upper electrode layer 313). This more effectively increases the amount of power generated. Even when the visible light reflective layer 8 includes a conductive layer such as a transparent conductive layer, the upper electrode layer 313 of the power generation unit 3 and the visible light reflective layer 8 are disposed at a distance from each other, thereby preventing electrical conduction between the power generation unit 3 and the visible light reflective layer 8. When the visible light reflective layer 8 includes Ag, the photoelectric conversion layer 312 and the visible light reflective layer 8 are disposed at a distance from each other, which prevents deterioration due to reaction of iodide ions in the perovskite compound with Ag contained in the visible light reflective layer 8.

[0065] The distance H may be, for example, 0.4 mm or more, which makes it possible to obtain the above-mentioned advantages more reliably and effectively.

[0066] In the photoelectric conversion device 100 of this embodiment, the photoelectric conversion layer 312 is configured to mainly absorb visible light to perform photoelectric conversion. With this configuration, the visible light reflected by the visible light reflecting layer 8 can be more efficiently absorbed by the photoelectric conversion layer 312 and used for power generation, thereby further increasing the amount of power generation. As an example, the average visible light absorption rate of the power generation layer PV including the photoelectric conversion layer 312 is 60% or more (see FIG. 13B ).

[0067] In the photoelectric conversion device 100 of this embodiment, the visible light reflective layer 8 is disposed on the second substrate 2. This allows the visible light reflective layer 8 to be more reliably disposed away from the power generation unit 3 in the Z direction. Furthermore, the distance H (here, the thickness of the intermediate layer 5) can be easily adjusted. In this example, the visible light reflective layer 8 is in contact with the main surface 2a of the second substrate 2; however, the visible light reflective layer 8 need only be supported by the main surface 2a, and does not have to be in direct contact with the main surface 2a. For example, the first layer 8 may be provided so as to be supported by the main surface 2a of the second substrate 2 via another material layer.

[0068] The structure formed by the visible light reflective layer 8 and the second substrate 2 is referred to as the "first structure." The reflectance of the first structure for light of at least a portion of the wavelengths in the wavelength range of 300 nm to 800 nm when the light is incident on the first structure from the visible light reflective layer 8 side may be 20% or more. This allows visible light transmitted through the visible light transmission region r1 to be used more efficiently for power generation.

[0069] In the photoelectric conversion device 100 of this embodiment, when viewed along the Z direction, the visible light reflective layer 8 is disposed so as to at least partially overlap with the visible light transmission region r1. With this configuration, visible light that has passed through the visible light transmission region r1 is likely to be incident on and reflected by the visible light reflective layer 8. This makes it possible to increase the amount of visible light returned to the power generation unit 3 by the visible light reflective layer 8.

[0070] In the sealed space SP, the visible light reflective layer 8 may be disposed over substantially the entire main surface 2 a of the second substrate 2. This can further increase the proportion of light reflected by the visible light reflective layer 8 out of the visible light transmitted through the visible light transmission region r1.

[0071] (Modification 1) The configuration of the photoelectric conversion device of this embodiment is not limited to the configuration of the photoelectric conversion device 100 described above with reference to FIGS.

[0072] 1 to 6, the visible light reflective layer 8 is supported by the second substrate 2, but the visible light reflective layer 8 may be supported by the first substrate 1. The visible light reflective layer 8 may be formed, for example, on the main surface 1a of the first substrate 1 with the power generating unit 3 and the intermediate layer 5 interposed therebetween.

[0073] 1 to 6, when viewed along the Z direction, the visible light reflective layer 8 overlaps (covers) the entire visible light transmitting region r1 located between the power generating units 3, but it is sufficient that the visible light reflective layer 8 overlaps at least a part of the visible light transmitting region r1. The visible light reflective layer 8 may be patterned.

[0074] The positions, shapes, materials, etc. of the solar cell 31, the extraction electrode 4, and the sealing member 6 are not limited to the example shown in the drawing. The power generation unit 3 is required to have at least one solar cell, and may have only a single solar cell.

[0075] (Examples and Comparative Examples) A ​​comparative device (hereinafter abbreviated as "device") not having a first layer and devices of Examples will be described. In the Examples and Comparative Examples, optical properties were measured with reference to JIS R 3106.

[0076] <Comparative Example> First, a photoelectric conversion device (hereinafter abbreviated as "device") of a comparative example was fabricated, and its optical characteristics were examined. The device of the comparative example has a layered structure composed of a first substrate, a power generation layer, an intermediate layer, and a second substrate. The device of the comparative example differs from the photoelectric conversion device 100 shown in FIGS. 1 to 6 in that it does not have a first layer, and that the power generation layer is formed over substantially the entire surface of the first substrate, with no visible light transmission region formed. The materials and thicknesses of each layer in the comparative example are shown below. First substrate 1: glass substrate (thickness 3.2 mm) Second substrate 2: glass substrate (thickness 6.0 mm) Power generation layer PV: photoelectric conversion layer: n-type semiconductor layer (thickness 20 nm) Perovskite layer (thickness 550 nm) P-type semiconductor layer (thickness 70 nm) Molybdenum oxide film (thickness 5 nm) Lower electrode layer: FTO film (thickness 300 nm) Upper electrode layer: ITO film (thickness 100 nm) Intermediate layer 5: resin layer (thickness: for example 2.0 mm)

[0077] The optical characteristics of the comparative device were measured when light was incident approximately perpendicularly on the light-receiving surface 1b of the first substrate 1. FIG. 13A shows the spectral transmittance, spectral reflectance, and spectral absorptance of the comparative device. FIG. 13B shows the spectral absorptances of the comparative device, substrates 1 and 2, intermediate layer 5, and power-generating layer PV. Here, the spectral absorptance A_d of the comparative device and the spectral absorptances A_1, 2, and 5 of the substrates 1 and 2 and intermediate layer 5 were measured. The spectral absorptance A_PV of the power-generating layer PV was calculated by subtracting the spectral absorptance A_1, 2, and 5 from the spectral absorptance A_d. Therefore, the spectral absorptance A_PV is the spectral absorptance of the power-generating layer PV after a portion of the light has been absorbed by the first substrate 1. It is believed that the actual spectral absorptance of the power-generating layer PV will be higher than the value shown in FIG. 13A .

[0078] As can be seen from FIG. 13A , the transmittance of the comparative device is low in the visible light region (less than 10% in this example), rises sharply around a wavelength of 800 nm, and is higher in the near-infrared region than in the visible light region. The absorptance is higher in the visible light region than in the near-infrared region, for example, approximately 80% or higher. Furthermore, from FIG. 13B , it is believed that the high absorptance of the comparative device in the visible light region is due to the power generation layer (photoelectric conversion layer) selectively absorbing visible light. In FIG. 13B , the average absorptance of the power generation layer is 60% or higher. Considering that the actual absorptance is higher than the value shown in FIG. 13B as described above, and that the photoelectric conversion layer is the main absorber of visible light in the power generation layer, the average absorptance of the photoelectric conversion layer for visible light is believed to be, for example, 60% or higher.

[0079] 7 is an enlarged cross-sectional view schematically illustrating a device according to an embodiment. The layer structure of the device 101 according to the embodiment is the same as that of the photoelectric conversion device 100 shown in FIGS. 1 to 6. In this embodiment, a heat-reflecting glass (thickness: 6.0 mm, Sunlux (registered trademark) T manufactured by AGC) having a metal film coated on its surface is used as the second substrate 2 (first structure) having a visible light reflective layer 8 formed on its surface.

[0080] Light incident on the device 101 of the embodiment behaves as shown by the arrows in Figure 7. When sunlight is incident on the light-receiving surface 1b of the device 101, a portion of the visible light VIS contained in the sunlight enters the visible light absorption region r2, is absorbed by the power generation unit 3, and is converted into electricity. Another portion of the visible light VIS passes through the visible light transmission region r1 between two adjacent power generation units 3, and reaches the visible light reflecting layer 8. Of the visible light that reaches the visible light reflecting layer 8, light 91 within a certain wavelength range is reflected by the visible light reflecting layer 8. A portion of the reflected light 91 enters the power generation unit 3 from the upper electrode side and can be used for photoelectric conversion. A portion 92 of the visible light that reaches the visible light reflecting layer 8 and is not reflected can pass through the visible light reflecting layer 8 and the second substrate 2 and enter indoors.

[0081] In this way, according to the device 101 of the embodiment, by utilizing the visible light VIS reflected by the visible light reflecting layer 8, it is possible to increase the amount of power generated by the power generation unit 3 while allowing a portion of the visible light VIS to be transmitted indoors, thereby brightening the indoor space.

[0082] Furthermore, by providing the visible light reflective layer 8, it is possible to reduce the amount of visible light VIS transmitted indoors and the amount of visible light VIS absorbed by the second substrate 2. Therefore, it is possible to reduce the solar heat gain coefficient of the photoelectric conversion device 101.

[0083] In order to confirm the effect of the visible light reflective layer 8, the optical characteristics of the first structure (visible light reflective layer 8 and second substrate 2) in the example device 101 were measured. Fig. 8A is a diagram showing the measurement results of the optical characteristics of the first structure when light is incident approximately perpendicularly on the surface of the visible light reflective layer 8.

[0084] As can be seen from Figure 8A, the reflectance of the first structure is approximately 10% at a wavelength of 300 nm, but increases towards a wavelength of 800 nm, reaching approximately 50% near the wavelength of 800 nm. Generally, the reflectance of visible light from a glass substrate alone is approximately 10%, so providing the visible light reflective layer 8 increases the reflectance of visible light. By using such a first structure, in the device 101, visible light that has passed through the visible light transmission region r1 is easily reflected by the first structure and incident on the power generation unit 3. As a result, the amount of power generated by the device 101 can be increased.

[0085] Furthermore, the transmittance of the first structure for visible light is 5% or more (approximately 10%), and it is understood that a see-through type device 101 can be realized.

[0086] Furthermore, the first structure has a higher reflectance (over 50% in this example) in the near-infrared region of wavelengths 800 nm to 1800 nm than in the visible light region. By providing such a first structure, near-infrared light incident on the light-receiving surface 1b is less likely to be transmitted through the device 101 in the thickness direction. Therefore, the solar heat gain coefficient of the device 101 can be more effectively reduced.

[0087] Alternatively, a different heat-reflecting glass (thickness: 6.0 mm, Sunlux® T manufactured by AGC) may be used as the first structure. The optical characteristics of the first structure in this case are shown in FIG. 8B . In the example shown in FIG. 8B , the reflectance of the first structure is 20% or more (approximately 28%) across almost the entire visible and near-infrared regions. The provision of the visible light reflective layer 8 increases the reflectance of visible light and near-infrared light. Using such a first structure increases the power generation capacity of the device 101 and further reduces the solar heat gain coefficient. Furthermore, in this example, it can be seen that the visible light transmittance is high (approximately 28%), enabling even better see-through characteristics to be achieved.

[0088] 14 , a third modification of the photoelectric conversion device of the present disclosure may have a configuration in which the visible light reflective layer 8 is disposed on the back surface side of the second substrate 2. That is, the visible light reflective layer may be provided on the outer surface of the second substrate instead of the surface inside the sealed space.

[0089] However, in the case of Modification 3, the amount of power generated may be smaller than in the examples and other modifications. In the device 300 of Modification 3 shown in FIG. 14 , a portion of the visible light VIS that passes through the visible light transmission region r1 and heads toward the visible light reflection layer 8 is absorbed by the second substrate 2 or reflected at the interface between the second substrate 2 and the intermediate layer 5. Furthermore, a portion of the light reflected by the visible light reflection layer 8 may also be absorbed by the second substrate 2. As a result, the proportion of light 91 that is reflected by the visible light reflection layer 8 and enters the power generation unit 3 among the visible light VIS that passes through the visible light transmission region r1 is reduced. Therefore, the amount of power generated by the power generation unit 3 may be smaller than in the examples. Furthermore, because the visible light VIS that passes through the visible light transmission region r1 is more likely to be absorbed by the second substrate 2, the amount of light 92 that passes through the device 300 and enters the room may also be reduced.

[0090] Furthermore, in the device 300 of the third modification, the visible light reflective layer 8 is more susceptible to deterioration due to reaction with the outside air than in the example. When the visible light reflective layer 8 deteriorates, the reflectivity of the visible light reflective layer 8 for visible light may decrease. As a result, the amount of power generation using the light 91 reflected by the visible light reflective layer 8 may decrease.

[0091] Second Embodiment A photoelectric conversion device according to a second embodiment differs from the photoelectric conversion device according to the first embodiment shown in FIGS. 1 to 6 in that a photoelectric conversion layer containing a perovskite compound is used as the first layer.

[0092] Fig. 9 is a schematic end view showing a photoelectric conversion device according to the second embodiment. Fig. 10 is a schematic enlarged end view of a region R1 shown in Fig. 9. The following description will mainly focus on differences from the photoelectric conversion device 100 shown in Figs. 1 to 6.

[0093] 9 and 10 , the photoelectric conversion device 200 of this embodiment includes a first substrate 1, a second substrate 2, a plurality of first power generation units 3A, a plurality of second power generation units 3B, and a sealing member 6. The plurality of first power generation units 3A are arranged at a distance from each other on the main surface 1a of the first substrate 1. The plurality of second power generation units 3B are arranged at a distance from each other on the main surface 2a of the second substrate 2. These power generation units 3A, 3B are arranged in a sealed space SP formed by the sealing member 6 and the first and second substrates 1 and 2.

[0094] As shown in FIG. 10 , each of the first power generation units 3A and the second power generation units 3B has a configuration similar to that of the power generation unit 3 in the photoelectric conversion device 100 of the first embodiment. Each of the first power generation units 3A includes a first power generation layer PV1 including, from the principal surface 1a side, a lower electrode layer 311A, a photoelectric conversion layer 312A (sometimes referred to as the “first photoelectric conversion layer”) containing a perovskite compound, and an upper electrode layer 313A. Each of the second power generation units 3B includes a second power generation layer PV2 including, from the principal surface 2a side, a lower electrode layer 311B, a photoelectric conversion layer 312B (sometimes referred to as the “second photoelectric conversion layer”) containing a perovskite compound, and an upper electrode layer 313B. The second photoelectric conversion layer 312B is disposed at a distance in the Z direction from the first power generation unit 3A. The first power generation layer PV1 and the second power generation layer PV2 may be disposed at a distance in the Z direction.

[0095] In this embodiment, when viewed along the Z direction, on the first substrate 1 on which the first power generation units 3A are provided, the region r1A located between adjacent first power generation units 3A is referred to as the "visible light transmission region," and the region r2A on which the first power generation units 3A (photoelectric conversion layer 312A) are located is referred to as the "visible light absorption region." Similarly, when viewed along the Z direction, on the second substrate 2 on which the second power generation units 3B are provided, the region r1B located between adjacent second power generation units 3B is referred to as the "visible light transmission region," and the region r2B on which the second power generation unit 3B (photoelectric conversion layer 312B) is located is referred to as the "visible light absorption region."

[0096] The first power generation unit 3A and the second power generation unit 3B may be configured to have similar optical properties. Specifically, the photoelectric conversion layers 312A and 312B may both have similar absorption wavelengths. Furthermore, the photoelectric conversion layers 312A and 312B may both contain similar elements. In this embodiment, the photoelectric conversion layers 312A and 312B both contain a perovskite compound. Here, the perovskite compounds contained in the photoelectric conversion layers 312A and 312B may have the same composition. In this embodiment, both the photoelectric conversion layers 312A and 312B are layers that mainly absorb visible light to perform photoelectric conversion. The average visible light absorptance of the photoelectric conversion layers 312A and 312B may be, for example, 60% or more.

[0097] 9 , the entire photoelectric conversion layer 312B is located in the sealed space SP. As with the first layer (visible light reflective layer 8) of the first embodiment, the sealing member 6 may be disposed in a second region a2 located outside a first region a1 of the main surface 2 a of the second substrate 2 that overlaps with the photoelectric conversion layer 312B when viewed along the Z direction. Note that the photoelectric conversion layer 312B may extend from the sealed space SP between the second substrate 2 and the sealing member 6.

[0098] Although not shown in Figure 9, the photoelectric conversion device 200 further includes a pair of first extraction electrodes (see Figure 1) electrically connected to each of the multiple power generation units 3A, and a pair of second extraction electrodes electrically connected to each of the multiple power generation units 3B.

[0099] 9 and 10 , when viewed along the Z direction, the photoelectric conversion layer 312A of the first power generation unit 3A and the photoelectric conversion layer 312B of the second power generation unit 3B may be arranged to overlap each other. In this example, the width and arrangement pitch of the first power generation unit 3A in the Y direction are configured to be the same as the width and arrangement pitch of the second power generation unit 3B in the Y direction. In the Y direction, the positions of the first power generation unit 3A and the second power generation unit 3B are generally aligned.

[0100] 9 and 10 , in the photoelectric conversion device 200 of this embodiment, a plurality of power generation units 3 and a first layer are arranged in the sealed space SP between the first substrate 1 and the second substrate 2, at a distance H in the thickness direction (Z direction) of the first substrate 1. The first layer is a second photoelectric conversion layer 312B containing a perovskite compound.

[0101] 9 , when sunlight containing visible light VIS is incident on the light-receiving surface 1b, a portion of the visible light VIS is absorbed by the first photoelectric conversion layer 312A of the first power generation unit 3A and converted into electricity. Another portion of the visible light VIS passes through the visible light transmission region r1A located between two adjacent first power generation units 3A and is absorbed by the second photoelectric conversion layer 312B and converted into electricity. In this way, further power generation can be performed using the light that has passed through the visible light transmission region r1A, thereby increasing the amount of power generated by the photoelectric conversion device 200.

[0102] Furthermore, according to the above configuration, since the first power generation unit 3A and the second power generation unit 3B are arranged in the sealed space SP, deterioration of the first photoelectric conversion layer 312A and the second photoelectric conversion layer 312B due to outside air (oxygen, moisture, etc.) can be suppressed.

[0103] The photoelectric conversion device 200 of this embodiment further includes a plurality of second power generation units 3B arranged at a distance from each other on the main surface 2a of the second substrate 2 in the sealed space SP. Each second power generation unit 3B includes a second photoelectric conversion layer 312B. With this configuration, a portion of visible light VIS incident on the light-receiving surface 1b of the photoelectric conversion device 200 can pass between two adjacent first power generation units 3A and between two adjacent second power generation units 3B and enter the room from the back surface side of the second substrate 2. This can brighten the room.

[0104] Furthermore, in the photoelectric conversion device 200 of this embodiment, the first photoelectric conversion layer 312A and the second photoelectric conversion layer 312B are arranged to overlap each other when viewed along the Z direction, thereby improving the design of the photoelectric conversion device 200 when viewed along the Z direction.

[0105] The light absorption wavelength ranges of the first photoelectric conversion layer 312A and the second photoelectric conversion layer 312B may be substantially the same. In this embodiment, each of the first photoelectric conversion layer 312A and the second photoelectric conversion layer 312B may be a visible light absorbing layer having an average visible light absorption rate of, for example, 60% or more. This allows visible light incident on the visible light absorption region r2A to be more efficiently converted into electricity by the first photoelectric conversion layer 312A, and visible light transmitted through the visible light transmission region r1A to be more efficiently converted into electricity by the second photoelectric conversion layer 312B. This allows a higher proportion of visible light incident on the photoelectric conversion device 200 to be used for power generation.

[0106] (Modification 2) Fig. 11 is a schematic end view showing Modification 2 of the photoelectric conversion device of this embodiment, Fig. 12 is a schematic enlarged end view of a region R2 shown in Fig. 11 .

[0107] In the photoelectric conversion device 201 of variant example 2, when viewed along the Z direction, the second photoelectric conversion layer 312B of the second power generation unit 3B is arranged so as to at least partially overlap with the visible light transmitting region r1A located between two adjacent first power generation units 3A.

[0108] In this modification 2, when viewed along the Z direction, the second power generation unit 3B (second photoelectric conversion layer 312B) overlaps only a portion of the visible light transmitting region r1A. In the example shown in Figures 11 and 12, the width and arrangement pitch of the first power generation unit 3A in the Y direction are configured to be the same as the width and arrangement pitch of the second power generation unit 3B in the Y direction. The first power generation unit 3A and the second power generation unit 3B are arranged so as to be offset from each other in the Y direction.

[0109] In the photoelectric conversion device 201 of the present modified example 2, when viewed along the Z direction, the second photoelectric conversion layer 312B is disposed so as to at least partially overlap with the visible light transmitting region r1A located between two adjacent first power generation units 3B, which makes it easier for light transmitted through the visible light transmitting region r1A to enter the second power generation unit 3B, thereby more effectively increasing the amount of power generated in the second power generation unit 3B.

[0110] When viewed along the Z direction, the second photoelectric conversion layer 312B may be disposed so as to cover only a portion of the visible light transmission region r1A. That is, as shown in FIG. 12 , the length W in the Y direction of the portion of the second power generation unit 3B that overlaps with the visible light transmission region r1A may be smaller than the distance g in the Y direction of the visible light transmission region r1A. This allows visible light to be transmitted indoors via the visible light transmission regions r1A and r1B while increasing the amount of power generated by the second power generation unit 3B. The length W may be, for example, equal to or less than half of the distance g.

[0111] When viewed along the Z direction, the second power generation unit 3B may be arranged to cover the entire visible light transmission region r1A (to overlap the entire visible light transmission region r1A), which makes it easier for light that has passed through the visible light transmission region r1A to be incident on the second power generation unit 3B, thereby further increasing the amount of power generated by the second power generation unit 3B.

[0112] The photoelectric conversion devices 200 and 201 shown in Figures 9 to 12 can also be manufactured by a method similar to the method shown in Figure 6. However, in this embodiment, a first substrate having a plurality of first power generation units formed on its main surface and a second substrate having a plurality of second power generation units formed on its main surface are prepared. The method for forming the first power generation units and the second power generation units may be the same as the method for forming the power generation units in the first embodiment. Subsequent processes may be the same as those in the first embodiment.

[0113] 9 to 12, the structure, material, and arrangement pitch of the first power generation section 3A are the same as those of the second power generation section 3B, but they may be different from each other. Furthermore, the first power generation section 3A and / or the second power generation section 3B may be arranged regularly, quasi-regularly, or randomly in the Y direction.

[0114] The present disclosure is not limited to the above-described embodiments and examples, and design modifications are possible within the scope of the present disclosure. Furthermore, by appropriately combining the configurations of any of the various embodiments (including modified examples) illustrated, the effects of each of the embodiments can be achieved.

[0115] Overview of Embodiments <1> A photoelectric conversion device according to the present disclosure comprises: a light-transmitting first substrate; a plurality of first power generation units arranged on a main surface of the first substrate at a distance from each other; a second substrate arranged to face the first substrate with the plurality of first power generation units sandwiched therebetween; a sealing member; and a first layer, wherein each of the plurality of first power generation units comprises a first photoelectric conversion layer containing a perovskite compound, the plurality of first power generation units being arranged in a sealed space formed between the first substrate and the second substrate by the sealing member, and the first layer being arranged in the sealed space at a distance from the plurality of first power generation units in a thickness direction of the first substrate, and the first layer is either a visible light reflective layer having a reflectance for light of at least a portion of wavelengths within a wavelength range of visible light that is higher than the reflectance of light of the at least a portion of wavelengths of the second substrate, or a second photoelectric conversion layer containing a perovskite compound.

[0116] <2> The photoelectric conversion device according to <1>, wherein the first layer is disposed on the second substrate.

[0117] <3> In the photoelectric conversion device according to <1> or <2>, the first layer is the visible light reflective layer, and when light of at least some of the wavelengths enters a structure formed by the visible light reflective layer and the second substrate from the first layer side, the reflectance of the structure is 20% or more.

[0118] <4> In the photoelectric conversion device described in <3>, when viewed along the thickness direction of the first substrate, the visible light reflective layer is arranged so as to at least partially overlap with a region located between two adjacent first power generation units among the plurality of first power generation units.

[0119] <5> The photoelectric conversion device according to <4>, wherein the visible light reflective layer is disposed on substantially the entire main surface of the second substrate facing the first substrate.

[0120] <6> The photoelectric conversion device according to any one of <3> to <5>, wherein the visible light reflective layer contains Ag, Ti, or Sn.

[0121] <7> The photoelectric conversion device according to any one of <1> to <6>, wherein a hollow layer is provided between the first power generation section and the first layer.

[0122] <8> The photoelectric conversion device according to <7>, wherein the hollow layer is a nitrogen layer, an argon layer, or a krypton layer.

[0123] <9> The photoelectric conversion device according to any one of <1> to <11>, further comprising a resin layer located between the first power generation section and the first layer.

[0124] <10> The photoelectric conversion device according to <9>, wherein the resin layer contains a thermoplastic resin.

[0125] <11> The photoelectric conversion device according to <10>, wherein the softening point of the thermoplastic resin is 120° C. or lower.

[0126] <12> The photoelectric conversion device according to any one of <1> to <11>, wherein the first layer and the first power generation section are spaced apart from each other by 0.4 mm or more in the thickness direction.

[0127] <13> In the photoelectric conversion device according to any one of <1> to <12>, when viewed along the thickness direction, a main surface of the second substrate facing the first substrate includes a first region overlapping the first layer and a second region located outside the first region and not overlapping the first layer, and the sealing member is located in the second region.

[0128] <14> Another photoelectric conversion device of the present disclosure includes: a light-transmitting first substrate; a plurality of first power generation units arranged on a main surface of the first substrate at a distance from each other; a second substrate arranged to face the first substrate with the plurality of first power generation units sandwiched therebetween; a sealing member; and a first layer, wherein each of the plurality of first power generation units includes a first photoelectric conversion layer containing a perovskite compound, and the plurality of first power generation units are arranged in a sealed space formed between the first substrate and the second substrate by the sealing member, and the first layer is arranged in the sealed space at a distance from the plurality of first power generation units in a thickness direction of the first substrate, and the first layer includes a second photoelectric conversion layer containing a perovskite compound.

[0129] <15> The photoelectric conversion device according to <14>, wherein the first layer is disposed on the second substrate.

[0130] <16> The photoelectric conversion device according to <14> or <15>, further comprising: a plurality of second power generation units arranged at a distance from each other on the main surface of the second substrate in the sealed space, each of the plurality of second power generation units comprising the second photoelectric conversion layer.

[0131] <17> The photoelectric conversion device according to <16>, wherein the plurality of first power generation units and the plurality of second power generation units have similar optical characteristics.

[0132] <18> The photoelectric conversion device according to <17>, wherein the first photoelectric conversion layer and the second photoelectric conversion layer have the same absorption wavelength.

[0133] <19> The photoelectric conversion device according to <18>, wherein the first photoelectric conversion layer and the second photoelectric conversion layer contain the same elements as those contained in the perovskite compound.

[0134] <20> In the photoelectric conversion device described in <16>, when viewed along the thickness direction of the first substrate, the second photoelectric conversion layer is arranged so as to at least partially overlap with a region located between two adjacent first power generation units among the plurality of first power generation units.

[0135] <21> The photoelectric conversion device according to <16>, wherein the first photoelectric conversion layer and the second photoelectric conversion layer are arranged to overlap each other when viewed along the thickness direction of the first substrate.

[0136] <22> The photoelectric conversion device according to <16>, wherein the first photoelectric conversion layer and the second photoelectric conversion layer each have an average absorptance of 60% or more for visible light.

[0137] The photoelectric conversion device according to the present disclosure has excellent durability and can increase the amount of power generated, and is therefore useful as a photoelectric conversion device that can be applied to, for example, building materials.

[0138] REFERENCE SIGNS LIST 1 First substrate 1a, 2a Main surface 1b Light receiving surface 2 Second substrate 3 Power generation section 3A First power generation section 3B Second power generation section 4 Extraction electrode 4A First electrode 4B Second electrode 5 Intermediate layer 6 Sealing member 8 Visible light reflecting layer 31 Solar cell 100, 200, 201 Photoelectric conversion device 311, 311A, 311B Lower electrode layer 312, 312A, 312B Photoelectric conversion layer 313, 313A, 313B Upper electrode layer VIS Visible light NIR Near infrared light PV Power generation layer PV1 First power generation layer PV2 Second power generation layer r1, r1A, r1B Visible light transmitting region r2, r2A, r2B Visible light absorbing region SP Sealed space

Claims

1. A photoelectric conversion device comprising: a light-transmitting first substrate; a plurality of first power generation units arranged on a main surface of the first substrate at a distance from each other; a second substrate arranged to face the first substrate with the plurality of first power generation units sandwiched between them; a sealing member; and a first layer, wherein each of the plurality of first power generation units comprises a first photoelectric conversion layer containing a perovskite compound, the plurality of first power generation units being arranged in a sealed space formed between the first substrate and the second substrate by the sealing member, the first layer being arranged in the sealed space at a distance in the thickness direction of the first substrate from the plurality of first power generation units, and the first layer being a visible light reflective layer having a reflectance for light of at least some wavelengths within a wavelength range of visible light that is higher than the reflectance of the second substrate for light of at least some of the wavelengths.

2. The photoelectric conversion device according to claim 1, wherein the first layer is disposed on the second substrate.

3. A photoelectric conversion device as described in claim 1 or 2, wherein the reflectance of light of at least some of the wavelengths in the structure formed by the visible light reflective layer and the second substrate when the light is incident on the structure from the first layer side is 20% or more.

4. A photoelectric conversion device as described in claim 3, wherein, when viewed along the thickness direction of the first substrate, the visible light reflective layer is arranged to at least partially overlap with a region located between two adjacent first power generation units among the plurality of first power generation units.

5. The photoelectric conversion device according to claim 4, wherein the visible light reflective layer is disposed over substantially the entire main surface of the second substrate facing the first substrate.

6. The photoelectric conversion device according to claim 3, wherein the visible light reflective layer contains Ag, Ti or Sn.

7. The photoelectric conversion device according to claim 1 or 2, wherein a hollow layer is provided between the first power generation section and the first layer.

8. The photoelectric conversion device according to claim 7, wherein the hollow layer is a nitrogen layer, an argon layer, or a krypton layer.

9. The photoelectric conversion device according to claim 1 or 2, further comprising a resin layer located between the first power generation section and the first layer.

10. The photoelectric conversion device according to claim 9, wherein the resin layer includes a thermoplastic resin.

11. The photoelectric conversion device according to claim 10, wherein the softening point of the thermoplastic resin is 120°C or lower.

12. The photoelectric conversion device according to claim 1 or 2, wherein the first layer and the first power generation section are spaced apart from each other by 0.4 mm or more in the thickness direction.

13. A photoelectric conversion device as described in claim 1 or 2, wherein, when viewed along the thickness direction, the main surface of the second substrate facing the first substrate includes a first region overlapping the first layer and a second region located outside the first region and not overlapping the first layer, and the sealing member is located in the second region.

14. A photoelectric conversion device comprising: a light-transmitting first substrate; a plurality of first power generation units arranged on a main surface of the first substrate at a distance from each other; a second substrate arranged to face the first substrate with the plurality of first power generation units sandwiched between them; a sealing member; and a first layer, wherein each of the plurality of first power generation units comprises a first photoelectric conversion layer containing a perovskite compound, the plurality of first power generation units being arranged in a sealed space formed between the first substrate and the second substrate by the sealing member, the first layer being arranged in the sealed space at a distance from the plurality of first power generation units in the thickness direction of the first substrate, and the first layer including a second photoelectric conversion layer containing a perovskite compound.

15. The photoelectric conversion device of claim 14, wherein the first layer is disposed on the second substrate.

16. A photoelectric conversion device as described in claim 14 or 15, further comprising a plurality of second power generation units arranged at a distance from each other on the main surface of the second substrate in the sealed space, each of the plurality of second power generation units comprising the second photoelectric conversion layer.

17. The photoelectric conversion device according to claim 16, wherein the plurality of first power generation units and the plurality of second power generation units have similar optical characteristics.

18. The photoelectric conversion device according to claim 17, wherein the first photoelectric conversion layer and the second photoelectric conversion layer have the same absorption wavelength.

19. The photoelectric conversion device according to claim 18, wherein the first photoelectric conversion layer and the second photoelectric conversion layer are both perovskite compounds containing the same elements.

20. A photoelectric conversion device as described in claim 16, wherein, when viewed along the thickness direction of the first substrate, the second photoelectric conversion layer is arranged to at least partially overlap with a region located between two adjacent first power generation units among the plurality of first power generation units.

21. The photoelectric conversion device according to claim 16, wherein the first photoelectric conversion layer and the second photoelectric conversion layer are arranged to overlap each other when viewed along the thickness direction of the first substrate.

22. The photoelectric conversion device according to claim 16, wherein the first photoelectric conversion layer and the second photoelectric conversion layer each have an average absorptance of 60% or more for visible light.

Images