Photoelectric conversion device

Abstract

A photoelectric conversion device according to the present disclosure comprises: a translucent first substrate; a power generation unit that is disposed on the first substrate and has a photoelectric conversion layer containing a perovskite compound; a second substrate disposed so as to face the first substrate with the power generation unit sandwiched therebetween; a sealing member; and a first layer containing a material different from that of the second substrate. The power generation unit is disposed in a sealing space formed between the first substrate and the second substrate by the sealing member. The first layer is disposed in the sealing space set apart from the power generation unit in the thickness direction of the first substrate, and, when viewed along the thickness direction of the first substrate, the photoelectric conversion layer and the first layer at least partially overlap. The first layer is a layer in which the transmittance for first light having a wavelength of 800-1300 nm is lower than the transmittance for visible light having a wavelength of 300-800 nm.

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 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. In addition, there are cases where a lower solar heat gain coefficient (higher heat shielding properties) is required, for example, from the viewpoint of reducing the energy consumption of air conditioning.

[0006] An object of the present disclosure is to solve the above-mentioned problems and to provide a photovoltaic conversion device that can improve durability and reduce the solar heat gain coefficient.

[0007] The photoelectric conversion device disclosed herein comprises a light-transmitting first substrate, a power generation unit disposed on the first substrate and having a photoelectric conversion layer containing a perovskite compound, a second substrate disposed opposite the first substrate with the power generation unit sandwiched therebetween, a sealing member, and a first layer containing a material different from that of the second substrate, wherein the power generation unit is disposed in a sealed space formed between the first and second substrates by the sealing member, the first layer is disposed in the sealed space at a distance from the power generation unit in the thickness direction of the first substrate, and when viewed along the thickness direction of the first substrate, the photoelectric conversion layer and the first layer at least partially overlap, and the first layer is a layer whose transmittance for first light with a wavelength of 800 nm to 1300 nm is lower than its transmittance for visible light with a wavelength of 300 nm to 800 nm.

[0008] According to the present disclosure, it is possible to provide a photovoltaic conversion device that can improve durability and reduce the solar heat gain coefficient.

[0009] 13A is a schematic top view of a photoelectric conversion device according to an embodiment. FIG. 13B is a schematic end view taken along line II-II in FIG. 1. FIG. 13C is a schematic enlarged end view of region P indicated by a dashed line in FIG. 2. FIG. 13D is a schematic top view of a photoelectric conversion device according to Modification 1. FIG. 13D is a schematic end view taken along line V-V in FIG. 4. FIG. 13E is a schematic enlarged end view of region Q indicated by a dashed line in FIG. 4. FIG. 13F is a flowchart showing an example of a method for manufacturing a photoelectric conversion device. FIG. 13F is an enlarged cross-sectional view schematically showing a photoelectric conversion device according to Example 1. FIG. 13G is an enlarged cross-sectional view schematically showing a photoelectric conversion device according to Example 2. FIG. 13H is a diagram illustrating measurement results of the optical characteristics of a first structure in Example 2. FIG. 13I is a diagram illustrating measurement results of the optical characteristics of a second substrate in Example 2. FIG. 13J is an enlarged cross-sectional view schematically showing a photoelectric conversion device according to a comparative example. FIG. 13I is a diagram illustrating the optical characteristics (spectral transmittance, spectral reflectance, and spectral absorptance) of a photoelectric conversion device according to a comparative example. FIG. 13J 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. 13F is a graph showing the results of multiplying the spectral transmittance of FIG. 13A by a weighting coefficient required for calculating the solar heat gain coefficient. 10 is an enlarged cross-sectional view schematically showing a photoelectric conversion device of Modification 3. FIG. 11 is an enlarged cross-sectional view schematically showing a photoelectric conversion device of Modification 3. FIG.

[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 a structure that can be suitably applied to building materials.

[0011] The inventors first investigated the optical properties of perovskite solar cells and obtained the following findings. Perovskite solar cells primarily absorb, for example, visible light and convert it into electricity. Near-infrared light, which has a high thermal effect, is easily transmitted through perovskite solar cells without being absorbed (see Figures 13A to 13C, described below). When such perovskite solar cells are used as window materials, a higher proportion of near-infrared light contained in sunlight passes through the window material and enters the interior of the building. As a result, the solar heat gain coefficient of the window material increases, which may increase the cooling load, especially in the summer. In this specification, "visible light" refers to light with a wavelength of 300 nm to 800 nm, for example. "Near-infrared light" refers to light with a wavelength of 800 nm to 1800 nm, for example. Furthermore, near-infrared light with a wavelength of 800 nm to 1300 nm is referred to as "first light."

[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] Therefore, the inventors discovered a structure in which a power generation unit (perovskite solar cell) and a layer (hereinafter referred to as the "first layer") having a lower transmittance for first light than for visible light are arranged in a sealed space sealed from the outside. A photovoltaic device having such a structure can suppress the solar heat gain coefficient because near-infrared light, which has a strong thermal effect, is less likely to penetrate the photovoltaic device. Furthermore, by arranging the power generation unit and the first layer in the sealed space, the durability of the photovoltaic device can be improved. Specifically, a decrease in conversion efficiency due to degradation of the perovskite compound caused by reaction with external air (oxygen, moisture, etc.) can be suppressed. Note that a decrease in conversion efficiency increases the amount of visible light absorbed by the perovskite compound that is converted into thermal energy rather than converted into electricity. This increases the amount of heat dissipated indoors from the photovoltaic device, potentially further increasing the solar heat gain coefficient. In contrast, the above structure can suppress an increase in heat dissipation due to degradation of the perovskite compound, thereby suppressing an increase in the solar heat gain coefficient. In addition, it is possible to suppress changes in optical properties caused by deterioration of the first layer due to reaction with the outside 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] 1 to 3, the basic configuration of a photoelectric conversion device according to an embodiment of the present disclosure will be described. 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.

[0018] As shown in Figures 1 to 3, the photoelectric conversion device 100 comprises a first substrate 1 and a second substrate 2, a power generation section 3 including a photoelectric conversion layer, a pair of extraction electrodes 4 electrically connected to the power generation section 3, a sealing member 6, and a first layer 8.

[0019] 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, with the outer surface on the first substrate 1 side facing outdoors and the outer surface on the second substrate 2 side facing indoors.

[0020] In this embodiment, the first substrate 1 and the second substrate 2 face each other with the power generation 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 generation unit 3 and the first layer 8 are disposed in the sealed space SP.

[0021] 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 allows the photoelectric conversion device 100 to function as a bifacial module.

[0022] 1 to 3, the first substrate 1 and the second substrate 2 each have a roughly rectangular parallelepiped shape. In FIGS. 1 to 3, 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.

[0023] 2 and 3, 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 a back surface 1b opposite to the main surface 1a of the first substrate 1. In this specification, the back surface 1b of the first substrate 1 may be referred to as the "light-receiving surface."

[0024] The power generating unit 3 is disposed on the main surface 1a of the first substrate 1. The power generating unit 3 may be disposed over substantially the entire main surface 1a. As shown in FIG. 3 , the power generating unit 3 includes a stacked structure (hereinafter referred to as the "power generating 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.

[0025] The power generation layer PV comprises at least one solar cell (perovskite solar cell) 31. In the example shown in FIGS. 1 to 3, a plurality of solar cells 31 are arranged in the X direction on the main surface 1a. Two adjacent solar cells 31 are connected in series. The specific structures of the power generation layer PV and the solar cell 31 will be described later.

[0026] The sealing member 6 prevents moisture and gas from entering the sealed space SP, in which the power generation unit 3 is 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 power generation unit 3 when viewed from the Z direction. When viewed along 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.

[0027] 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.

[0028] 1 , the extraction electrode 4 includes a first electrode 4A electrically connected to the solar cell 31 located on the leftmost side (−X side) of the 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.

[0029] The first layer 8 is a layer having a lower transmittance for the first light having a wavelength of 800 nm to 1300 nm than for visible light having a wavelength of 300 nm to 800 nm. The first layer 8 may be a layer having a higher reflectance or absorptance for the first light than for visible light. The first layer 8 may be a layer that selectively reflects or absorbs light in a specific wavelength range that includes the wavelength range of the first light. The first layer 8 may be a layer having a higher reflectance for the first light than for visible light and a higher absorptance for the first light than for visible light.

[0030] As shown in Figure 3, the first 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 first 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 first 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 first layer 8, thereby suppressing a decrease in conversion efficiency.

[0031] When viewed along the Z direction, the first layer 8 at least partially overlaps with the photoelectric conversion layer 312 of the power generation unit 3. This allows near-infrared light that has passed through the photoelectric conversion layer 312 to be reflected or absorbed by the first layer 8, thereby reducing the transmittance of near-infrared light of the photoelectric conversion device 100. When viewed along the Z direction, the first layer 8 may be disposed so as to overlap with the entire power generation unit 3.

[0032] In the example shown in FIG. 2 , the first layer 8 is disposed only within 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 2 a of the second substrate 2 includes a first region a1 that overlaps the first layer 8 and a second region a2 that is located outside the first region a1 and does not overlap the first layer 8. The sealing member 6 is located in the second region a2. With this configuration, the entire first layer 8 can be disposed within the sealed space SP, thereby more effectively suppressing changes in optical properties due to deterioration of the first layer 8. Furthermore, since the first layer 8 is not interposed between the sealing member 6 and the second substrate 2, deterioration of adhesion between the sealing member 6 and the second substrate 2 can be suppressed.

[0033] The first layer 8 may extend between the second substrate 2 and the sealing member 6. For example, the first 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 first layer 8 after the first layer 8 is formed over the entire substrate surface. This allows for a reduction in the number of manufacturing steps and manufacturing costs.

[0034] Each component of the photoelectric conversion device 100 will be described in more detail below.

[0035] (First Layer) The first layer 8 may be composed of a single layer or may have a laminated structure. The first layer 8 includes a material different from that of the second substrate 2. "The first layer includes a material different from that of the second substrate" includes cases where at least a portion of the materials constituting the first layer 8 and the second substrate 2 are different. As an example, the main components of the materials may be different from each other. The material of the first layer 8 is not particularly limited, but includes metals such as Ag and Sn. The thickness of the first layer 8 is not particularly limited, but is, for example, 30 nm to 500 nm.

[0036] The first layer 8 may be, for example, a near-infrared light reflecting layer having a higher reflectance for the first light than for visible light, or a near-infrared light absorbing layer having a higher absorbance for the first light than for visible light. In the following description, the average reflectance, average absorbance, and average transmittance of the first light refer to the average reflectance, average absorbance, and average transmittance in the wavelength range of 800 nm to 1300 nm, respectively. The average reflectance, average absorbance, and average transmittance of visible light refer to the average reflectance, average absorbance, and average transmittance in the wavelength range of 300 nm to 800 nm, respectively.

[0037] Near-infrared light reflective layer The near-infrared light reflective layer may include, for example, a metal film, a metal oxide film, and / or a metal nitride film. Examples of the metal film include metal films of silver (Ag), gold (Au), copper (Cu), aluminum (Al), platinum (Pt), etc. Examples of the metal oxide film include titanium oxide (TiO ２ ), tin oxide (SnO ２ ), zinc oxide (ZnO), tungsten oxide, indium tin oxide (ITO), fluorine-doped tin oxide (FTO), aluminum-doped zinc oxide (AZO), and gallium zinc oxide (GZO). Metal nitride films include titanium nitride (TiNx), chromium nitride (CrNx), and the like.

[0038] For example, the near-infrared light reflective layer may be a laminated film in which a metal film is disposed between two metal oxide films, or may be a solar radiation-shielding low-E (low emissivity) film.

[0039] Near-infrared light absorbing layer The near-infrared light absorbing layer is, for example, a layer containing an infrared absorber. The near-infrared light absorbing layer may be a resin layer containing an infrared absorber. As the infrared absorber, for example, known inorganic infrared absorbers such as indium tin oxide, indium oxide, tin oxide, silicon oxide, aluminum oxide, zinc oxide, titanium oxide, and tungsten oxide may be used. Alternatively, known organic infrared absorbers such as phthalocyanine compounds may be used.

[0040] The first layer 8 and the second substrate 2 of the first structure constitute a structure that prevents near-infrared light that has passed through the power generating unit 3 from passing indoors. Such a structure (in this example, a laminate of the first layer 8 and the second substrate 2) is called the "first structure." The average transmittance of the first light of the first structure is, for example, 60% or less. The average transmittance of the visible light of the first structure may be higher than the average transmittance of the first light, for example, 70% or more. It may also be higher than 60%.

[0041] When the first layer 8 is a near-infrared light reflecting layer, the average reflectance of the first structure for the first light is, for example, 20% or more. The average reflectance of the first structure for visible light may be lower than the average reflectance of the first light. When the first layer 8 is a near-infrared light absorbing layer, the average absorptance of the first structure for the first light is, for example, 20% or more. The average absorptance of the first structure for visible light may be lower than the average absorptance of the first light.

[0042] (Intermediate Layer) The intermediate layer 5 is, for example, a hollow layer. By providing the hollow layer between the power generation section 3 and the first layer 8, the insulating effect of the hollow layer can suppress deterioration of the photoelectric conversion layer 312 due to heat emitted from the first layer 8. Furthermore, the insulating performance of the photoelectric conversion device 100 can be improved.

[0043] 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.

[0044] 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.

[0045] The intermediate layer 5 may be made of a resin such as ethylene-vinyl acetate copolymer (EVA), polyolefin (PO), or polyvinyl butyral (PVB).

[0046] 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.

[0047] 3 , each of the solar cells 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, the lower electrode layer 311 is a layer including a plurality of lower electrodes (lower electrodes of a plurality of solar cells 31), the upper electrode layer 313 is a layer including upper electrodes of a plurality of solar cells 31, and the photoelectric conversion layer 312 is a layer including photoelectric conversion units of a plurality of solar cells 31.

[0048] In two adjacent solar cell units 31, the upper electrode of one solar cell is electrically connected to the lower electrode of the other solar cell, for example, in a hole formed in the photoelectric conversion layer 312. In this way, the multiple solar cell units 31 that make up the power generation unit 3 are connected in series.

[0049] 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.

[0050] 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.

[0051] The lower electrode layer 311 is a transparent conductive layer having light-transmitting properties. The upper electrode layer 313 may be a transparent conductive layer or may not have light-transmitting properties. 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. The upper electrode layer 313 may be, for example, a carbon electrode.

[0052] 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.

[0053] 1 to 3 , in the photoelectric conversion device 100 of this embodiment, a power generation unit 3 having a photoelectric conversion layer 312 containing a perovskite compound and a first layer 8 containing a material different from that of the second substrate 2 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. When viewed along the Z direction, the first layer 8 and the photoelectric conversion layer 312 at least partially overlap. The first layer 8 is a layer whose transmittance for first light with a wavelength of 800 nm to 1300 nm is lower than its transmittance for visible light with a wavelength of 300 nm to 800 nm.

[0054] With the above configuration, among the light transmitted through the photoelectric conversion layer 312, near-infrared light (particularly the first light), which has a large thermal effect, is less likely to transmit through the photoelectric conversion device 100 in the Z direction. This makes it possible to reduce the amount of solar heat transmitted through the photoelectric conversion device 100 (see FIGS. 8 and 9 ). As a result, the solar heat gain coefficient of the photoelectric conversion device 100 can be reduced.

[0055] Furthermore, with the above configuration, the first layer 8 is located closer to the light incident side than the second substrate 2, making it difficult for near-infrared light (first light) to be incident on the second substrate 2. This reduces the amount of near-infrared light absorbed by the second substrate 2, making it possible to suppress re-radiation of heat from the second substrate 2 to the indoors. This therefore makes it possible to further reduce the solar heat gain coefficient.

[0056] In this specification, the "solar heat gain coefficient of a photovoltaic device" refers to the ratio of the amount of heat flowing into the surface (exiting surface) opposite the light-receiving surface of the photovoltaic device to the amount of heat incident on the light-receiving surface. The amount of heat flowing into the exiting surface includes the amount of solar heat that passes through the photovoltaic device in the thickness direction (solar transmittance) and the amount of heat that is absorbed by the photovoltaic device and then re-radiated to the exiting surface (e.g., indoors).

[0057] Furthermore, according to the above configuration, the first layer 8 is a layer that transmits (reflects or absorbs) the first light less easily than visible light, and does not impede the transmission of visible light (as much as near-infrared light). Therefore, for example, the first layer 8 can be applied to a see-through photovoltaic device, which will be described later. Furthermore, when the power generation unit 3 functions as a bifacial solar cell, visible light contained in sunlight incident from the second substrate 2 side can be transmitted through the first layer 8, absorbed by the power generation unit 3, and converted into electricity. Therefore, a decrease in the amount of power generated by the first layer 8 can be suppressed.

[0058] 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 is unlikely to occur. Therefore, a decrease in conversion efficiency due to deterioration of the photoelectric conversion layer 312 can be suppressed. Furthermore, as described above, a decrease in conversion efficiency can increase the amount of visible light absorbed by the photoelectric conversion layer 312 that is converted into thermal energy, which can lead to an increase in 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 (perovskite compound) can be suppressed, thereby suppressing an increase in the solar heat gain coefficient. Furthermore, since the first layer 8 is disposed in the sealed space SP, deterioration of the first layer 8 due to moisture is unlikely to occur. Therefore, changes in optical properties (decrease in reflectance or absorptance of near-infrared light) due to deterioration of the first layer 8 can be suppressed. Therefore, an increase in the solar heat gain coefficient due to deterioration of the first layer 8 can be suppressed.

[0059] Furthermore, with the above configuration, the photoelectric conversion layer 312 and the first layer 8 are disposed at a distance H from each other, which has the following advantages: Even when the first layer 8 absorbs near-infrared light and dissipates heat, the temperature of the photoelectric conversion layer 312 is unlikely to rise. Therefore, thermal deterioration of the photoelectric conversion layer 312 can be suppressed. Even when the first layer 8 includes a conductor layer such as a transparent conductive layer, the upper electrode layer 313 of the power generation unit 3 and the first layer 8 are disposed at a distance from each other, thereby suppressing electrical conduction between the power generation unit 3 and the first layer 8. When the first layer 8 includes Ag, the photoelectric conversion layer 312 and the first layer 8 are disposed at a distance H from each other, which suppresses deterioration caused by reaction of iodide ions in the perovskite compound with the Ag contained in the first layer 8.

[0060] 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.

[0061] In the photoelectric conversion device 100 of this embodiment, the first layer 8 is disposed on the second substrate 2. This allows the first layer 8 to be more reliably disposed away from the power generation unit 3 in the Z direction, and the distance H (here, the thickness of the intermediate layer 5) can be increased. In this example, the first layer 8 is in contact with the main surface 2a of the second substrate 2; however, the first 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.

[0062] In the photoelectric conversion device 100 of this embodiment, the average transmittance of the first light through the structure (first structure) formed by the first layer 8 and the second substrate 2 is 60% or less. With this configuration, the amount of the first light that transmits through the photoelectric conversion device 100 in the thickness direction can be more effectively reduced, thereby further reducing the solar heat gain coefficient.

[0063] In conventional devices, the use of a power generation layer PV that does not easily absorb (easily transmits) near-infrared light can result in high solar transmittance (see FIG. 12 ). In contrast, in this embodiment, a portion of the near-infrared light that is not absorbed by the power generation layer PV but is transmitted can be reflected or absorbed by the first layer 8, thereby more effectively reducing the solar heat gain coefficient.

[0064] (Variation 1) Fig. 4 is a schematic top view showing Variation 1 of the photoelectric conversion device of this embodiment. Fig. 5 is a schematic end view taken along line VV shown in Fig. 4. Fig. 6 is a schematic enlarged end view of region Q shown in Fig. 4. The following explanation will mainly focus on differences from the photoelectric conversion device 100 shown in Figs. 1 to 3.

[0065] 4, the photoelectric conversion device 200 of the first modification example differs from the photoelectric conversion device 100 shown in FIGS. 1 to 3 in that the power generation unit 3 includes a plurality of strings 30 arranged at a distance from each other when viewed along the Z direction. The power generation unit 3 is configured to allow visible light to pass through a region r1 between two adjacent strings 30 (see-through type).

[0066] A plurality of strings 30 are provided on the main surface 1a of the first substrate 1. Each of the plurality of strings 30 is a solar cell element string in which a plurality of solar cell cells 31 are connected in series. In this example, each string 30 extends approximately in the X direction. The structure of the X-Z end face of the solar cell 31 that constitutes the string 30 is similar to the end face structure shown in FIG.

[0067] Each string 30 is electrically connected to a first electrode 4A located at one end in the X direction of the string 30 and a second electrode 4B located at the other end, thereby connecting the multiple strings 30 in parallel.

[0068] As shown in Fig. 5, the multiple strings 30 are arranged at a distance g from each other in the Y direction. In the example shown in Fig. 6, the photoelectric conversion layers 312 and the upper electrode layers 313 of two adjacent strings 30 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 strings 30. In other words, the lower electrodes of solar cell cells 31 located at the same position in the X direction are connected to each other. The lower electrode layers 311 of two adjacent strings 30 may also be arranged at a distance g from each other.

[0069] When viewed along the Z direction, the photoelectric conversion layer 312 is not formed in a region r1 of the power generation unit 3 that is located between adjacent strings 30. A lower electrode layer 311 may be disposed, but the lower electrode layer 311 is a transparent electrode that is translucent. For this reason, the region r1 is more likely to transmit visible light than the region r2 in which the photoelectric conversion layer 312 is formed. In this specification, the region r1 that does not include the photoelectric conversion layer 312 and has a high transmittance of visible light is referred to as the "visible light transmitting region." Furthermore, the region r2 that includes the photoelectric conversion layer 312 and has a high absorption rate of visible light is referred to as the "visible light absorbing region."

[0070] The material and optical properties of the first layer 8 may be the same as those of the first layer 8 of the above-described photoelectric conversion device 100. However, in the present first modification, a light-transmitting layer is used as the first layer 8.

[0071] In the first modification, for example, when sunlight is incident on the light-receiving surface 1b of the first substrate 1, the visible light that enters the visible light absorption region r2 of the power generation unit 3 is absorbed by the photoelectric conversion layer 312. On the other hand, a portion of the visible light that enters the visible light transmission region r1 of the power generation unit 3 is transmitted through the near-infrared light reflecting layer 8A and can be emitted indoors from the back surface side of the second substrate 2, thereby brightening the indoor space. A portion of the near-infrared light in the sunlight is transmitted through the visible light transmission region r1 or the visible light absorption region r2 of the power generation unit 3 and is reflected or absorbed by the first layer 8. Therefore, the proportion of near-infrared light that transmits through the photoelectric conversion device 200 can be reduced, thereby lowering the solar heat gain coefficient.

[0072] As described above, according to the photoelectric conversion device 200 of the first modification, the power generation section 3 has the visible light transmitting region r1, and therefore it is possible to reduce the solar heat gain coefficient while transmitting a predetermined proportion of visible light.

[0073] (Modification 2) The configuration of the photoelectric conversion device of the present disclosure is not limited to the configurations of the photoelectric conversion devices 100 and 200 described above with reference to FIGS.

[0074] 1 to 6 include a near-infrared light reflecting layer or a near-infrared light absorbing layer as the first layer 8, but the first layer 8 may be a stacked film including both a near-infrared light reflecting layer and a near-infrared light absorbing layer. The first layer 8 may also be a layer that functions as both a near-infrared light reflecting layer and a near-infrared light absorbing layer. Furthermore, a layer that reflects or absorbs near-infrared light may be separately provided on the back surface of the second substrate 2 (the surface opposite to the main surface 2a).

[0075] 1 to 6 , the first layer 8 is supported by the second substrate 2, but the first layer 8 may also be supported by the first substrate 1. The first layer 8 may be formed, for example, on the main surface 1 a of the first substrate 1 via the power generation unit 3 or the intermediate layer 5. For example, the first layer 8 may be provided so as to be supported by the main surface 1 a of the first substrate 1 via the power generation unit 3. In this case, the first layer 8 may be located between the power generation unit 3 and the intermediate layer 5.

[0076] In Figures 1 to 6, the first layer 8 overlaps the entire power generation section 3 (photoelectric conversion layer 312) when viewed along the Z direction, but it is sufficient for the first layer 8 to overlap at least a portion of the photoelectric conversion layer 312.

[0077] 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.

[0078] (Method for Manufacturing Photoelectric Conversion Device) FIG. 7 is a flowchart showing an example of a method for manufacturing the photoelectric conversion device 100 (FIGS. 1 to 3) of this embodiment.

[0079] 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 are each formed by a known method such as coating or sputtering, and can be patterned by laser processing or the like. 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.

[0080] Also, a second substrate having a first layer formed on its main surface is prepared. The first layer can be formed on the main surface of the second substrate by, for example, sputtering, vapor deposition, coating, printing, or the like. Alternatively, a glass substrate having a reflective film or an absorbing film that can function as the first layer pre-formed on its main surface may be used as the second substrate. For example, a glass substrate having a metal oxide film (e.g., Ag) pre-formed on its main surface may be used as the second substrate. ２ Alternatively, a substrate coated with a thin film (O film) may be used. If necessary, the first layer may be patterned to remove a portion of the first layer located in the region where the sealing member is to be formed.

[0081] 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 formed on the second substrate. After this, a sealing member is formed between the first substrate and the second substrate to seal the power generation section. The extraction electrode is arranged so as to penetrate the sealing member or to extend to the outside through the gap between the sealing member and the first substrate. In this manner, a photoelectric conversion device is manufactured.

[0082] 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.

[0083] 8 to 13C, a comparative example device (hereinafter abbreviated as "device") not having a first layer and the devices of Examples 1 and 2 will be described. In the examples and comparative examples, optical properties were measured with reference to JIS R 3106.

[0084] <Comparative Example> Figure 12 is an enlarged cross-sectional view schematically showing a device of a comparative example. The device 301 of the comparative example differs from the photoelectric conversion device 100 shown in Figures 1 to 3 in that it does not have a first layer. The material and thickness of each layer in the comparative example are as follows: 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)

[0085] The optical characteristics of the comparative device 301 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 301, substrates 1 and 2, intermediate layer 5, and power-generating layer PV. Here, the spectral absorptance A_301 of the comparative device 301 and the spectral absorptances A_1, 2, and 5 of the substrates 1 and 2 and intermediate layer 5 were measured, and 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_301. 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 . FIG. 13C is a diagram showing the results of multiplying the spectral transmittance of FIG. 13A by a weighting factor indicating the standard spectral distribution of solar radiation.

[0086] 13A, the transmittance of the comparative device 301 is low in the visible light region (10% or less 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 reflectance is kept low in the visible to near-infrared region (40% or less in this example). The absorptance is higher in the visible light region than in the near-infrared region, for example, about 80% or more.

[0087] From Figure 13B, it is believed that the reason the absorptance of device 301 is high in the visible light region is because the power generation layer PV selectively absorbs visible light. In Figure 13B, the absorptance of the power generation layer PV containing a perovskite compound for visible light is approximately 60% or more, but the absorptance drops significantly around a wavelength of 800 nm, and the absorptance of near-infrared light is 20% or less. Meanwhile, the absorptance of the glass substrate (first substrate 1, intermediate layer 5, and second substrate 2) gradually increases from a wavelength of 500 nm to a wavelength of 1800 nm. However, the difference between the absorptance of the glass substrate for visible light and the absorptance of near-infrared light is smaller than the difference in absorptance of the power generation layer PV. Therefore, as shown in Figures 13A and 13B, the absorptance of device 301 as a whole depends on the absorption characteristics of the power generation layer PV and is higher in the visible light region than in the near-infrared region.

[0088] Furthermore, it can be seen from FIG. 13C that the amount of solar radiation transmitted by the device 301 of the comparative example is increased due to the transmission of mainly near-infrared light (particularly the first light having a wavelength of 800 nm to 1300 nm) of sunlight.

[0089] FIG. 12 schematically illustrates the behavior of light incident on the comparative device 301 based on the measurement results shown in FIGS. 13A to 13C. As shown in FIG. 12, when sunlight is incident on the light-receiving surface 1b of the device 301, most of the visible light (VIS) of the sunlight is absorbed primarily by the power-generating layer PV. Meanwhile, most of the near-infrared light (NIR) is transmitted through the power-generating layer PV in the thickness direction. Some of the near-infrared light (NIR) is absorbed by the glass substrates (first substrate 1 and second substrate 2), but the light not absorbed by these substrates is emitted from the back surface of the second substrate 2. Furthermore, as indicated by the dashed arrows, heat may be re-radiated from the first substrate 1 and second substrate 2, which have become hot due to the absorption of near-infrared light (NIR).

[0090] Therefore, for example, if the device 301 of the comparative example is used as a window material for a building, near-infrared light (NIR), which is contained in sunlight and has a high thermal effect, passes through the window material and enters the building, resulting in a high solar radiation transmittance. Furthermore, heat may be radiated indoors from the second substrate 2 that has absorbed the near-infrared light (NIR). As a result, the solar heat gain coefficient of the device 301 may be further increased.

[0091] Example 1 Figure 8 is an enlarged cross-sectional view schematically illustrating a device of Example 1. The layer structure of device 101 of Example 1 is the same as that of photoelectric conversion device 100 shown in Figures 1 to 3. However, device 101 of Example 1 has a near-infrared light reflective layer 8A as a first layer. Near-infrared light reflective layer 8A is, for example, an Ag layer (thickness: 300 nm, for example). The materials and thicknesses of each layer other than the first layer are not particularly limited, but may be the same as those of device 301 of the comparative example (Figure 12).

[0092] FIG. 8 shows a schematic diagram of the behavior of light incident on the device 101 of Example 1. As in the comparative example, in Example 1, most of the visible light VIS incident on the light-receiving surface 1b of the device 101 is absorbed primarily by the power-generating layer PV. Meanwhile, a portion of the near-infrared light NIR contained in sunlight that passes through the power-generating layer PV is reflected by the near-infrared light reflecting layer 8A. The reflected light may then pass through the power-generating layer PV again and exit to the outdoors from the light-receiving surface 1b side of the first substrate 1. Therefore, compared to the comparative example, the proportion of near-infrared light NIR that penetrates indoors can be reduced. Furthermore, in the device 101 of Example 1, the near-infrared light reflecting layer 8A is disposed closer to the light-receiving surface 1b (the light incident side) than the second substrate 2. Therefore, compared to the comparative example, the amount of near-infrared light NIR absorbed by the second substrate 2 is reduced, suppressing re-radiation of heat from the second substrate 2 to the indoors. In this way, the amount of transmitted near-infrared light NIR and the amount of heat dissipated from the second substrate 2 can be reduced compared to the comparative example, and therefore the solar heat gain coefficient can be reduced.

[0093] Example 2 Figure 9 is an enlarged cross-sectional view schematically illustrating a device of Example 2. The device 102 of Example 2 differs from the device 101 shown in Figure 9 in that it has a near-infrared light absorption layer 8B as a first layer. The near-infrared light absorption layer 8B is a metal oxide layer (thickness: e.g., 300 nm). The second substrate 2 is a glass substrate (thickness: 6.0 mm). The materials and thicknesses of each layer other than the first layer and the second substrate 2 are not particularly limited, but may be the same as those of the device 301 of the comparative example (Figure 12).

[0094] FIG. 9 schematically illustrates the behavior of light incident on the device 102 of Example 2. In Example 2, as in the comparative example, most of the visible light (VIS) is absorbed primarily by the power generation layer PV. Meanwhile, a portion of the near-infrared light (NIR) contained in sunlight is transmitted through the power generation layer PV and absorbed by the near-infrared light absorbing layer 8B. Therefore, compared to the comparative example, the proportion of near-infrared light (NIR) transmitted indoors can be reduced. Furthermore, in the device 102 of Example 2, the near-infrared light absorbing layer 8B is disposed closer to the light receiving surface 1b (the light incident side) than the second substrate 2, so the amount of near-infrared light (NIR) absorbed by the second substrate 2 is less than in the comparative example. Although heat is dissipated from the near-infrared light absorbing layer 8B to the second substrate 2, the temperature rise of the second substrate 2 can be suppressed more than in the comparative example, thereby reducing the amount of heat dissipated from the second substrate 2. Thus, the amount of near-infrared light (NIR) transmitted and the amount of heat dissipated from the second substrate 2 can be reduced more than in the comparative example, thereby reducing the solar heat gain coefficient.

[0095] Furthermore, in the device 102 of Example 2, the near-infrared light absorption layer 8B and the power generation layer PV are disposed apart from each other by the intermediate layer 5. This makes it possible to suppress deterioration of the power generation layer PV (particularly the photoelectric conversion layer) due to heat radiated from the near-infrared light absorption layer 8B that has absorbed the near-infrared light NIR.

[0096] In order to confirm the characteristics of the near-infrared light absorption layer 8B of Example 2, the optical characteristics of the first structure (near-infrared light absorption layer 8B and second substrate 2) and the optical characteristics of only the second substrate 2 in the device 102 of Example 2 were measured. Fig. 10 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 near-infrared light absorption layer. Fig. 11 is a diagram showing the measurement results of the optical characteristics of the second substrate when light is incident approximately perpendicularly on the main surface of the second substrate.

[0097] Comparing the transmittances shown in Figures 10 and 11, the presence of the near-infrared light absorption layer 8B reduces the transmittance of near-infrared light (particularly the first light with a wavelength of 800 to 1300 nm). For example, for light with a wavelength of 1000 nm, the transmittance of the second substrate 2 is approximately 80%, while the transmittance of the first structure is approximately 60%, a decrease of about 20%. On the other hand, the transmittance of visible light (particularly light with a wavelength of 300 to 600 nm) is approximately 80% in both cases, and is almost unchanged whether or not the near-infrared light absorption layer 8B is present. This shows that the transmittance of the first light through the near-infrared light absorption layer 8B is lower than the transmittance of visible light.

[0098] 10 and 11 , the absorptance of the first light is increased by providing the near-infrared light absorption layer 8B. On the other hand, the absorptance of visible light is almost unchanged regardless of the presence or absence of the near-infrared light absorption layer 8B. This shows that the near-infrared light absorption layer 8B is a layer that has a higher absorptance of the first light than of visible light.

[0099] 10 and 11 , it can be seen that, in Example 2, the first light transmitted through the power generating unit 3 is more easily absorbed by the near-infrared light absorbing layer 8B than in the comparative example where the near-infrared light absorbing layer 8B is not provided, and as a result, the first light is less likely to transmit to the back surface side of the second substrate 2 (see FIG. 9 ). Therefore, it can be seen that the solar heat gain coefficient can be lowered compared to the comparative example.

[0100] 10 and 11 show that the near-infrared light absorption layer 8B used in Example 2 is a layer that easily transmits visible light. The visible light transmittance of the near-infrared light absorption layer 8B is, for example, 70% or more. When such a first layer with excellent light transmittance is applied to a see-through photovoltaic device 200 such as those shown in FIGS. 4 to 6, it is possible to reduce the solar heat gain coefficient while maintaining the see-through characteristics of the photovoltaic device.

[0101] In Example 2, the effect of the near-infrared light absorbing layer was confirmed by measuring the optical properties of the first structure and the second substrate. For Example 1, by performing the same measurements as in Example 2, it was confirmed that the transmission of the first light was suppressed by the near-infrared light reflecting layer (see FIG. 8 ).

[0102] (Variation 3) A variation 3 of the photoelectric conversion device of the present disclosure may have a configuration in which the first layer is disposed on the back surface side of the second substrate, as shown in Figures 14 and 15. That is, the first layer may be provided on the outer surface of the second substrate, not on the surface inside the sealed space. However, in the case of variation 3, the solar heat gain coefficient or durability may be lower than in the examples and other variations, as described below.

[0103] The device 401 of Modification 3 shown in FIG. 14 differs from the device 101 of Example 1 ( FIG. 8 ) in that the near-infrared light reflecting layer 8A is disposed on the back surface side of the second substrate 2. In the device 401 of Modification 3, a portion of the near-infrared light NIR that passes through the power generation layer PV and toward the near-infrared light reflecting layer 8A is absorbed by the second substrate 2, and further, a portion of the light reflected by the near-infrared light reflecting layer 8A can also be absorbed by the second substrate 2. Therefore, compared to Example 1, the amount of near-infrared light NIR absorbed by the second substrate 2 is greater, and as a result, the amount of heat dissipation is also increased. Therefore, the solar heat gain coefficient may be higher compared to Example 1.

[0104] 15 differs from the device 102 (FIG. 9) of Example 2 in that the near-infrared light absorbing layer 8B is disposed on the back surface side of the second substrate 2. Because the near-infrared light absorbing layer 8B has a higher absorptivity for near-infrared light NIR than the second substrate 2, the near-infrared light NIR can be mainly absorbed by the near-infrared light absorbing layer 8B. Because the near-infrared light absorbing layer 8B is located closest to the indoors and is therefore more likely to dissipate heat indoors, the solar heat gain coefficient may be higher compared to Example 2.

[0105] Furthermore, in the devices 401 and 402 of Modification 3, the near-infrared light reflecting layer 8A or the near-infrared light absorbing layer 8B may react with the outside air and deteriorate, resulting in a decrease in the reflectance or absorptance of near-infrared light. As a result, near-infrared light may be more easily transmitted, which may further increase the solar heat gain coefficient.

[0106] 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.

[0107] Overview of Embodiments <1> A photoelectric conversion device according to the present disclosure includes: a light-transmitting first substrate; a power generation unit disposed on the first substrate and having a photoelectric conversion layer containing a perovskite compound; a second substrate disposed opposite the first substrate with the power generation unit sandwiched therebetween; a sealing member; and a first layer containing a material different from that of the second substrate, wherein the power generation unit is disposed in a sealed space formed between the first and second substrates by the sealing member, the first layer is disposed in the sealed space at a distance from the power generation unit in a thickness direction of the first substrate, and when viewed along the thickness direction of the first substrate, the photoelectric conversion layer and the first layer at least partially overlap, and the first layer has a lower transmittance for first light having a wavelength of 800 nm to 1300 nm than a transmittance for visible light having a wavelength of 300 nm to 800 nm.

[0108] <2> The photoelectric conversion device according to <1>, wherein the first layer is disposed on the second substrate.

[0109] <3> In the photoelectric conversion device according to <1> or <2>, an average transmittance of the structure for the first light when the first light is incident on the structure formed by the first layer and the second substrate from the first layer side is 60% or less.

[0110] <4> The photoelectric conversion device according to any one of <1> to <3>, wherein the first layer contains Ag or Sn.

[0111] <5> The photoelectric conversion device according to any one of <1> to <4>, wherein the first layer is a near-infrared light reflective layer having a higher reflectance for near-infrared light than for visible light.

[0112] <6> In the photoelectric conversion device according to <5>, when the first light is incident on a structure formed by the first layer and the second substrate from the first layer side, the average reflectance of the structure for the first light is 20% or more.

[0113] <7> The photoelectric conversion device according to any one of <1> to <4>, wherein the first layer is a near-infrared light absorption layer having a higher absorptivity for near-infrared light than for visible light.

[0114] <8> In the photoelectric conversion device according to <7>, when the first light is incident on a structure formed by the first layer and the second substrate from the first layer side, the average absorptance of the structure for the first light is 20% or more.

[0115] <9> The photoelectric conversion device according to any one of <1> to <8>, wherein a hollow layer is provided between the power generation section and the first layer.

[0116] <10> The photoelectric conversion device according to <9>, wherein the hollow layer is a nitrogen layer, an argon layer, or a krypton layer.

[0117] <11> The photoelectric conversion device according to any one of <1> to <10>, further comprising a resin layer located between the power generation section and the first layer.

[0118] <12> The photoelectric conversion device according to <11>, wherein the resin layer contains a thermoplastic resin.

[0119] <13> The photoelectric conversion device according to <12>, wherein the softening point of the thermoplastic resin is 120° C. or lower.

[0120] <14> The photoelectric conversion device according to any one of <1> to <13>, wherein the first layer and the power generation section are spaced apart from each other by 0.4 mm or more in the thickness direction.

[0121] <15> In the photoelectric conversion device according to any one of <1> to <14>, 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.

[0122] The photovoltaic conversion device according to the present disclosure has excellent durability and can reduce the solar heat gain coefficient, and is therefore useful as a photovoltaic conversion device that can be applied to, for example, building materials.

[0123] REFERENCE SIGNS LIST 1 First substrate 1a, 2a Main surface 1b Light receiving surface 2 Second substrate 3 Power generating section 4 Extraction electrode 4A First electrode 4B Second electrode 5 Intermediate layer 6 Sealing member 8 First layer 8A Near-infrared light reflecting layer 8B Near-infrared light absorbing layer 30 String 31 Solar cell 100 to 102, 200 Photoelectric conversion device 311 Lower electrode layer 312 Photoelectric conversion layer 313 Upper electrode layer VIS Visible light NIR Near-infrared light PV Power generating layer r1 Visible light transmitting region r2 Visible light absorbing region SP Sealed space

Claims

1. A photoelectric conversion device comprising: a light-transmitting first substrate; a power generation unit disposed on said first substrate and having a photoelectric conversion layer containing a perovskite compound; a second substrate disposed opposite said first substrate with said power generation unit sandwiched therebetween; a sealing member; and a first layer containing a material different from that of said second substrate, wherein said power generation unit is disposed in a sealed space formed between said first and second substrates by said sealing member; said first layer is disposed in said sealed space at a distance from said power generation unit in a thickness direction of said first substrate; when viewed along the thickness direction of said first substrate, said photoelectric conversion layer and said first layer at least partially overlap; and said first layer is a layer having a lower transmittance for first light with a wavelength of 800 nm to 1300 nm than its transmittance for visible light with a wavelength of 300 nm to 800 nm.

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 average transmittance of the structure formed by the first layer and the second substrate for the first light when the first light is incident on the structure from the first layer side is 60% or less.

4. The photoelectric conversion device according to claim 1 or 2, wherein the first layer contains Ag or Sn.

5. The photoelectric conversion device according to claim 1 or 2, wherein the first layer is a near-infrared light reflective layer having a higher reflectance for near-infrared light than for visible light.

6. The photoelectric conversion device according to claim 5, wherein the average reflectivity of the structure formed by the first layer and the second substrate for the first light when the first light is incident on the structure from the first layer side is 20% or more.

7. The photoelectric conversion device according to claim 1 or 2, wherein the first layer is a near-infrared light absorption layer having a higher absorption rate for near-infrared light than for visible light.

8. A photoelectric conversion device as described in claim 7, wherein the average absorptance of the structure for the first light when the first light is incident on the structure formed by the first layer and the second substrate from the first layer side is 20% or more.

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

10. The photoelectric conversion device according to claim 9, wherein the hollow layer is a nitrogen layer, an argon layer, or a krypton layer.

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

12. The photoelectric conversion device according to claim 11, wherein the resin layer includes a thermoplastic resin.

13. The photoelectric conversion device according to claim 12, wherein the softening point of the thermoplastic resin is 120°C or lower.

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

15. 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.

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