JP2022168820A - Photoelectric conversion element, photoelectric conversion module having the same, photoelectric conversion device, mobile body, and building material - Google Patents

Abstract

To provide a photoelectric conversion element with a higher photoelectric conversion efficiency.SOLUTION: The photoelectric conversion element has a first electrode 7, a second electrode 3, and a photoelectric conversion layer 5 including an organic-inorganic perovskite compound arranged between the first electrode 7 and the second electrode 3. A particle layer 6 composed of particles mainly of a phthalocyanine compound is arranged between the photoelectric conversion layer 5 and the first electrode 7.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a photoelectric conversion element, and a photoelectric module, a photoelectric conversion device, a moving body, and a building material having the photoelectric conversion element.

In order to solve the problem of fossil energy depletion and the global environmental problems caused by the use of fossil energy, researches on renewable and clean alternative energy sources such as solar energy, wind power, water power, etc. are being actively conducted. there is Among them, interest in solar cells, which convert electrical energy directly from sunlight, has increased significantly. Here, the solar cell refers to a cell that absorbs light energy from sunlight and generates current-voltage using a photovoltaic effect in which electrons and charges are generated.
Currently, np diode-type silicon (Si) single crystal-based solar cells with light energy conversion efficiencies exceeding 20% are widely known and actually used for photovoltaic power generation. However, these have the problem of high cost per unit power, since they require a high-temperature treatment process and the material itself is expensive. Moreover, from the aspect of silicon resources, there is also a problem of supply.
On the other hand, solar cells using organic materials (hereinafter referred to as “organic solar cells”) do not require high-temperature processes, and can be produced using a sheet-like substrate by a so-called roll-to-roll method, enabling cost reduction. . Further improvements in power generation efficiency and durability are desired for the practical use of organic solar cells.
In particular, phthalocyanine compounds are being developed as materials for practical use of organic solar cells because they are excellent in light absorption, charge transport and chemical stability. For example, Patent Document 1 discloses that the photoelectric conversion efficiency is improved by using phthalocyanine particles as a light absorbing material in an organic solar cell having a bulk heterostructure. Further, in Patent Document 2, in an organic solar cell using a perovskite compound in a photoelectric conversion layer, an organically modified phthalocyanine compound is dissolved in an organic solvent and coated on the photoelectric conversion layer to form a film, thereby improving power generation efficiency. is disclosed.

JP 2012-119405 A JP 2016-139805 A

In the method disclosed in Patent Document 1, in order to obtain high power generation efficiency, it is necessary to dispose the charge transport material, the electron transport material, and the light absorber at equal distances, which poses the problem of being difficult to put into practical use. In addition, in the method disclosed in Patent Document 2, since the phthalocyanine compound is formed into a film in an amorphous state, the original charge transport ability cannot be expressed, and there is a problem that it is difficult to obtain high photoelectric conversion efficiency.
An object of the present invention is to provide a photoelectric conversion element with higher photoelectric conversion efficiency, and to provide a device such as a photoelectric conversion device using the photoelectric conversion element.

A first aspect of the present invention is a photoelectric conversion device having a first electrode, a second electrode, and a photoelectric conversion layer containing an organic-inorganic perovskite compound disposed between the first electrode and the second electrode. and
A particle layer composed of particles mainly composed of a phthalocyanine compound is provided between the photoelectric conversion layer and the first electrode.
A second aspect of the present invention is a photoelectric conversion module comprising a plurality of photoelectric conversion elements according to the first aspect of the present invention.
A third aspect of the present invention is a photoelectric conversion device comprising a photoelectric conversion element according to the first aspect of the present invention, and a power storage unit or an inverter connected to the photoelectric conversion element.
A fourth aspect of the present invention is a moving body comprising a photoelectric conversion element and a body provided with the photoelectric conversion element.
A fifth aspect of the present invention is a building material comprising the photoelectric conversion element of the first aspect of the present invention, a protective member for protecting the photoelectric conversion element, and a heat radiating member.

According to the present invention, a photoelectric conversion element having a higher photoelectric conversion efficiency is provided, and the photoelectric conversion element can be used to provide a photoelectric conversion module, a photoelectric conversion device, a moving object, and a building material having a high photoelectric conversion efficiency. .

BRIEF DESCRIPTION OF THE DRAWINGS It is a cross-sectional schematic diagram of one Embodiment of the photoelectric conversion element of this invention of the thickness direction. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view schematically showing one embodiment of a moving body provided with a photoelectric conversion element of the present invention; BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a perspective view schematically showing one embodiment of a building material provided with a photoelectric conversion element of the present invention;

A photoelectric conversion device of the present invention has a first electrode, a second electrode, and a photoelectric conversion layer containing an organic-inorganic perovskite compound disposed between the first electrode and the second electrode. is. In the present invention, a particle layer composed of particles mainly composed of a phthalocyanine compound is provided between the photoelectric conversion layer and the first electrode.

The particle layer according to the present invention is formed by dispersing particles containing a phthalocyanine compound in an organic solvent and applying the dispersion onto the photoelectric conversion layer. As a result of studies, the present inventors have found that a photoelectric conversion element having an excellent photoelectric conversion efficiency can be obtained by having such a particle layer. Although the details are not clear, the reason why the high photoelectric conversion efficiency is obtained in the present invention is considered as follows. By forming a film of the phthalocyanine compound in the form of particles, high crystallinity is maintained and the original charge transport ability of phthalocyanine can be exhibited. Furthermore, when the photoelectric conversion layer contains an inorganic or organic perovskite compound, submicron-scale unevenness occurs on the surface. By filling the unevenness with phthalocyanine particles, interfacial bonding is improved, resulting in extremely high photoelectric conversion efficiency. is estimated to be obtained.

In this specification, the term "layer" refers not only to a layer having a clear boundary or a flat thin film layer, but also to a layer having a concentration gradient in which the contained elements gradually change, and a layer together with other layers. It also means a layer capable of forming a complicated and intricate structure. Further, the elemental analysis of the layer can be performed, for example, by performing FE-TEM/EDS line analysis measurement of the cross section of the photoelectric conversion element and confirming the elemental distribution of the specific element.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail. The present invention is not limited to the following embodiments, and appropriate modifications, improvements, etc., are made to the following embodiments based on the ordinary knowledge of those skilled in the art within the scope of the present invention. is included in the scope of the present invention.

FIG. 1 is a cross-sectional view schematically showing the configuration of one embodiment of the photoelectric conversion element of the present invention. It has a second electrode 3 , an electron transport layer 4 , a photoelectric conversion layer 5 , a particle layer 6 and a first electrode 7 on a substrate 2 . One of the first electrode 7 and the second electrode 3 is an anode and the other is a cathode, and an electric current is generated in the configuration in which the first electrode 7 and the second electrode 3 are connected by an external circuit.

The photoelectric conversion layer 5 is excited by light incident through the substrate 2, the second electrode 3 and the electron transport layer 4, or the first electrode 7 and the particle layer 6 to generate electrons or holes. That is, the photoelectric conversion layer 5 generates current between the first electrode 7 and the second electrode 3 . The electron transport layer 4 is a layer arranged between the photoelectric conversion layer 5 and the two electrodes 3 and 7, and may not be formed in some cases. A plurality of electron transport layers 4 and photoelectric conversion layers 5 may be laminated. Such a form can also be called a tandem structure.

(substrate)
The photoelectric conversion element 1 of the present invention may have a substrate 2, and examples thereof include transparent glass substrates such as soda lime glass and non-alkali glass substrates, ceramic substrates, and transparent plastic substrates. When light is taken in from the first electrode 7 side, the substrate 2 can be made of an opaque material, and when light is taken in from the second electrode 3 side, the substrate 2 is made of a transparent material.

(electrode)
Materials for the first electrode 7 and the second electrode 3 are not particularly limited, and conventionally known materials can be used. For example, metals such as gold, silver, titanium, copper, sodium, sodium-potassium alloys, lithium, magnesium, aluminum, magnesium-silver mixtures, magnesium-indium mixtures, aluminum-lithium alloys, Al/Al ₂ O ₃ mixtures, Al /LiF mixture and the like. Examples of transparent electrode materials include CuI, ITO (indium tin oxide), SnO ₂ , AZO (aluminum zinc oxide), IZO (indium zinc oxide), GZO (gallium zinc oxide), FTO (fluorine-doped tin oxide), ), conductive transparent materials such as ATO (antimony-doped tin oxide), and conductive transparent polymers. These materials may be used alone, or two or more of them may be used in combination. In the first electrode 7 and the second electrode 3, at least one of the electrodes on the light incident side is a transparent electrode, and the other is a transparent electrode, even if it also serves as a reflective layer formed of a light reflective material. Alternatively, a transparent electrode having a reflective layer on the side opposite to the light incident side may be used. When the first electrode 7 is on the light incident side, the second electrode 3 may be a transparent electrode and the substrate 2 may be a reflective layer. Incidentally, the transparent electrode is often a patterned electrode.

(Photoelectric conversion layer)
The photoelectric conversion layer 5 contains an organic/inorganic perovskite compound represented by the general formula RMX ₃ (R is an organic molecule, M is a metal atom, and X is a halogen atom or a chalcogen atom). By using the organic-inorganic perovskite compound for the photoelectric conversion layer 5, the photoelectric conversion efficiency of the solar cell can be improved.

R in the general formula above is an organic molecule, and is preferably represented by _CpNmHn ( _p , _m , and n are all positive integers). Specifically, R is, for example, methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, dipentylamine, dihexylamine, trimethylamine, triethylamine, tripropyl amine, tributylamine, tripentylamine, trihexylamine, ethylmethylamine, methylpropylamine, butylmethylamine, methylpentylamine, hexylmethylamine, ethylpropylamine, ethylbutylamine, imidazole, azole, pyrrole, aziridine, azirine, Ions of azetidine, azeto, imidazoline, carbazole, aniline, pyridine, methylcarboxamine, ethylcarboxamine, propylcarboxamine, butylcarboxamine, pentylcarboxamine, hexylcarboxamine, formamidinium, guanidine (e.g. methylammonium (CH ₃ NH ₃ ), etc.) and phenethylammonium. Among them, methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, aniline, pyridine, propylcarboxamine, butylcarboxamine, pentylcarboxamine, formamidinium, guanidine ions and phenethylammonium are preferred. Ethylamine, propylamine, pentylcarboxyamine, formamidinium and guanidine ions are more preferred.

M is a metal atom such as lead, tin, bismuth, zinc, titanium, antimony, nickel, iron, cobalt, silver, copper, gallium, germanium, magnesium, calcium, indium, aluminum, manganese, chromium, molybdenum, europium and the like. Among them, lead, tin, and bismuth are preferable from the viewpoint of overlap of electron orbits. These metal atoms may be used alone, or two or more of them may be used in combination.

The above X is a halogen atom or a chalcogen atom such as chlorine, bromine, iodine, sulfur, selenium and the like. These halogen atoms or chalcogen atoms may be used alone, or two or more of them may be used in combination. Among them, a halogen atom is preferable because the organic-inorganic perovskite compound becomes easily soluble in an organic solvent by containing a halogen in the structure, and application to inexpensive printing methods and the like becomes possible. Furthermore, iodine is more preferable because it narrows the energy bandgap of the organic-inorganic perovskite compound.

The organic-inorganic perovskite compound preferably has a cubic structure in which a metal atom M is arranged at the center of the body, an organic molecule R is arranged at each vertex, and a halogen atom or a chalcogen atom X is arranged at the center of the face. Although the details are not clear, by having such a structure, the orientation of the octahedron in the crystal lattice can be easily changed. It is estimated that the conversion efficiency is improved.

The organic/inorganic perovskite compound used in the present invention is preferably a crystalline semiconductor. A crystalline semiconductor means a semiconductor whose X-ray scattering intensity distribution can be measured and a scattering peak can be detected. Since the organic-inorganic perovskite compound is a crystalline semiconductor, the mobility of electrons in the organic-inorganic perovskite compound is increased, and the photoelectric conversion efficiency of the photoelectric conversion element is improved.

The thickness of the photoelectric conversion layer according to the present invention is preferably 5 nm or more and 1000 nm or less. If the thickness is 5 nm or more, light can be sufficiently absorbed, and if the thickness is 1000 nm or less, the generated charge can be transported to each electrode. A more preferable lower limit is 10 nm or more, a more preferable upper limit is 700 nm, a still more preferable lower limit is 15 nm, and a further preferable upper limit is 500 nm.

In the present invention, the maximum height Rz of surface roughness of the photoelectric conversion layer 5 is measured as follows. First, the surface of the photoelectric conversion layer 5 is subjected to laser analysis using a laser microscope ("VK-X200" manufactured by Keyence) at a standard magnification of 150 times and a pitch of 0.2 μm. The obtained laser observation image is pretreated with cutoff values λs=0.25 μm and λc=0.25 mm to obtain the maximum height Rz of surface roughness.

(particle layer)
The photoelectric conversion element 1 of the present invention has a particle layer 6 composed of particles mainly composed of a phthalocyanine compound between the photoelectric conversion layer 5 and the first electrode 7 . Such particles preferably contain 50% by mass or more, more preferably 80% by mass or more and 99% by mass or less of the phthalocyanine compound in elemental analysis ratio measured by ICP/MS or the like. When the phthalocyanine compound is 50% by mass or more, the stability of the particles is high, which is preferable. When the phthalocyanine compound is 80% by mass or more, the π-π stack in the particles is strengthened and the charge transport ability is improved.

The thickness of the particle layer 6 is preferably 20 nm or more and 800 nm or less. When the thickness is 20 nm or more, the photoelectric conversion layer 5 can be sufficiently covered and charge transport can be performed smoothly. It is more preferably 50 nm or more and 600 nm or less, and still more preferably 50 nm or more and 400 nm or less.

In the present invention, the average particle diameter of the particles mainly composed of the phthalocyanine compound has a preferred upper limit of 300 nm and a preferred lower limit of 20 nm. If the average particle diameter is 300 nm or less, the unevenness of the photoelectric conversion layer 5 can be filled, and the charges generated in the photoelectric conversion layer 5 can be extracted smoothly. If the average particle diameter is 20 nm or more, the interfacial resistance between particles when filling the unevenness of the photoelectric conversion layer 5 can be reduced, and the charge transport performance can be smoothly performed. A more preferable upper limit of the average particle diameter of the particles is 250 nm, a more preferable lower limit is 60 nm, a still more preferable upper limit is 150 nm, and a further preferable lower limit is 70 nm.

The average particle size of the particles mainly composed of the phthalocyanine compound can be obtained by, for example, dynamic light scattering method, laser diffraction method, gravity sedimentation method, ultrasonic attenuation method, if the primary particle size of crystal particles of the phthalocyanine compound can be measured.・It can be obtained by using an image imaging method or the like. In the examples of the present invention, it was derived by an image imaging method using a SEM (scanning electron microscope). Specifically, first, using an SEM image of the particle layer 6 at a magnification of 100,000, crystal particles (10,000 or more) are extracted using image processing software Photoshop (manufactured by Adobe). Next, the area S of each crystal grain was determined, and the diameter of a circle having the same area as this area (=2×(S/π) ^1/2 ) was taken as the average grain size.

In the present invention, particles mainly composed of a phthalocyanine compound show peaks at Bragg angles 2θ of 7.4°±0.3° and 28.2°±0.3° in an X-ray diffraction spectrum using CuKα rays. It preferably contains crystal particles of a crystalline phthalocyanine compound. Further, such particles preferably include crystal particles of a phthalocyanine compound having a peak at 20 nm or more and 50 nm or less in a crystal grain size distribution measured using small-angle X-ray scattering, and having a half-value width of the peak of 50 nm or less. .

Powder X-ray diffraction measurement of particles mainly composed of a phthalocyanine compound was carried out under the following conditions.

[Powder X-ray diffraction measurement]
Measuring machine used: Rigaku Denki Co., Ltd., X-ray diffractometer "RINT-TTRII"
X-ray tube: Cu
X-ray wavelength: Kα1
Tube voltage: 50KV
Tube current: 300mA
Scanning method: 2θ scan Scanning speed: 4.0°/min
Sampling interval: 0.02°
Start angle 2θ: 5.0°
Stop angle 2θ: 35.0°
Goniometer: Rotor horizontal goniometer (TTR-2)
Attachment: Capillary rotation sample stage Filter: None Detector: Scintillation counter Incident monochrome: Used Slit: Variable slit (parallel beam method)
Counter monochromator: Not used Divergence slit: Open Divergence vertical limiting slit: 10.00 mm
Scattering slit: open Receiving slit: open

In the present invention, the phthalocyanine compound may have a metal ligand. Examples of coordinating metals include Ga, Cu, and Ti, among which Ga is preferred from the viewpoint of crystallinity. The coordination metal may have a substituent. Examples of the substituent include a hydroxy group and a halogen group, and among them, a hydroxy group is preferable from the viewpoint of charge transport ability. From these points of view, the phthalocyanine compound is particularly preferably hydroxygallium phthalocyanine.

In the photoelectric conversion element of the present invention, an electron transport layer may be arranged between the first electrode 7 and the photoelectric conversion layer 5 and/or between the second electrode 3 and the photoelectric conversion layer 5 . A photoelectric conversion element 1 shown in FIG. 1 is an example in which an electron transport layer 4 is arranged between a second electrode 3 and a photoelectric conversion layer 5 .

The material of the electron transport layer 4 is not particularly limited. Specific examples include cyano group-containing polyphenylene vinylene, boron-containing polymer, bathocuproine, bathophenanthrene, hydroxyquinolinatoaluminum, oxadiazole compound, benzimidazole compound, naphthalenetetracarboxylic acid compound, perylene derivative, Phosphine oxide compounds, phosphine sulfide compounds, fluoro group-containing phthalocyanines, titanium oxide, zinc oxide, indium oxide, tin oxide, gallium oxide, tin sulfide, indium sulfide, zinc sulfide and the like.

The electron transport layer 4 may consist of only a thin-film electron transport layer, but preferably includes a porous electron transport layer. In particular, when the photoelectric conversion layer 5 is a composite film containing an organic-inorganic perovskite compound, a more complicated composite film (a more complicated structure) is obtained, and the photoelectric conversion efficiency is increased. A composite photoelectric conversion layer 5 is preferably formed on the electron transport layer 4 .

The thickness of the electron transport layer 4 has a preferred lower limit of 1 nm and a preferred upper limit of 2000 nm. If the thickness is 1 nm or more, holes can be sufficiently blocked, and if the thickness is 2000 nm or less, it is difficult to become a resistance during electron transport, resulting in a high photoelectric conversion efficiency. A more preferable lower limit to the thickness is 3 nm, a more preferable upper limit is 1000 nm, a still more preferable lower limit is 5 nm, and a further preferable upper limit is 500 nm.

(Photoelectric conversion device)
A photoelectric conversion device of the present invention has a plurality of photoelectric conversion elements of the present invention, and when a plurality of photoelectric conversion elements are connected, it can be called a photoelectric conversion module. The photoelectric conversion elements may be stacked in order to increase the output voltage. A photoelectric conversion device includes the photoelectric conversion element of the present invention and an inverter. An inverter may be a converter that converts direct current to alternating current. The photoelectric conversion device may have a power storage unit connected to the photoelectric conversion element. The power storage unit is not limited as long as it can store electricity. For example, a secondary battery using lithium ion or the like, an all-solid battery, an electric double layer capacitor, and the like can be mentioned.

(moving object)
FIG. 2 is a perspective view schematically showing one embodiment of a moving body provided with the photoelectric conversion element of the present invention. A moving body 30 has a photoelectric conversion element 31 of the present invention and a body 32 having this photoelectric conversion element 31 . The photoelectric conversion element 31 is arranged at a position where the airframe 32 can receive external light. If the moving body 30 is an automobile, it may be placed on the roof. The electrical energy obtained by the photoelectric conversion element 31 may be used to power the moving body 30 or other electrical equipment. Electric energy generated from the power of the moving body 30 may be used to power the photoelectric conversion element 31 . If the moving body 30 is an automobile, frictional energy generated by braking may be converted into electrical energy and used to control the photoelectric conversion element 31 .
The mobile object 30 may be, for example, an automobile, a ship, an aircraft, or a drone. Although the structure of the body 32 of the moving body 30 is not particularly limited, it is preferably made of a material with high strength.

(building materials)
FIG. 3 is a perspective view schematically showing one embodiment of a building material provided with the photoelectric conversion element of the present invention. Building material 40 may be the roof of a building. A building material 40 of the present embodiment has a photoelectric conversion element 41 of the present invention, a protective member 42 that protects the photoelectric conversion element 41, a heat dissipation member 43, and exteriors 44a and 44b.

The building material 40 of the present invention may have a heat radiating member 43 having a higher thermal conductivity than the photoelectric conversion element 41 . When used on a roof or the like, the temperature of the photoelectric conversion element 41 may rise due to sunlight, and the photoelectric conversion efficiency may decrease. A decrease in photoelectric conversion efficiency can be reduced by using the heat radiating member 43 . Metals, alloys, liquid metals, liquid resins, and the like can be used for the heat radiating member 43 .

Further, the building material 40 of the present invention may have exteriors 44a and 44b. The exterior 44a and the exterior 44b may emit different colors or may be the same. 44a and 44b may be composed of the same member or may be composed of different members. Paint and a transparent substrate may be used as the exterior. Those having low light absorption and high heat shielding properties are preferable.

EXAMPLES The present invention will be described in more detail with reference to Examples below, but the present invention is not limited to these Examples. Also, "parts" in the following description are "parts by mass" unless otherwise specified.

[Preparation of Particles Mainly Containing Phthalocyanine Compound]
<Preparation of Particle 1>
Step (1)
In a nitrogen flow atmosphere, 5.46 parts of orthophthalonitrile and 45 parts of α-chloronaphthalene were charged into the reactor, heated to 30° C., and maintained at this temperature. Next, 3.75 parts of gallium trichloride were added at this temperature (30° C.). The water concentration of the mixed liquid at the time of charging was 150 ppm. After that, the temperature was raised to 200°C. The reaction was then carried out at a temperature of 200°C for 4.5 hours under an atmosphere of nitrogen flow, then cooled and the product was filtered when the temperature reached 150°C. The obtained filtrate was dispersed and washed with N,N-dimethylformamide at a temperature of 140° C. for 2 hours, and then filtered. The resulting filtrate was washed with methanol and then dried to obtain chlorogallium phthalocyanine particles with a yield of 71%.

Step (2)
4.65 parts of the chlorogallium phthalocyanine particles were dissolved in 139.5 parts of concentrated sulfuric acid at a temperature of 10.degree. At this time, as a filter, No. 5C (manufactured by Advantech) was used. The resulting wet cake (filtrate) was dispersed and washed with 2% aqueous ammonia for 30 minutes, and then filtered using a filter press. Then, the obtained wet cake (filtrate) was dispersed and washed with ion-exchanged water, and then filtered three times using a filter press. Finally, freeze-drying (freeze-drying) was performed to obtain hydroxygallium phthalocyanine particles (hydrated hydroxygallium phthalocyanine particles) having a solid content of 23% by mass with a yield of 71%. The hydroxygallium phthalocyanine particles are dried with a hyper dry dryer (trade name: HD-06R, frequency (oscillation frequency): 2455 MHz ± 15 MHz, manufactured by Biocon Japan) to obtain hydroxygallium phthalocyanine particles having a water content of 1.0% by mass or less. (crystal) was obtained.

Step (3)
5 parts of the hydroxygallium phthalocyanine particles were dispersed for 6 hours using a sand mill (K-800, manufactured by Igarashi Kikai Seisakusho (now Imex), disk diameter 70 mm, number of disks 5) containing 5 parts of DMF solvent and 5 parts of glass beads. Particle 1 was obtained by processing, filtering and drying.

Particles 2 to 16 shown in Table 1 having different particle sizes and crystallinities were produced by changing the dispersion time and the amount of glass beads in step (3). "Pc compound" in Table 1 means a phthalocyanine compound.

(Example 1)
[Washing of substrate and second electrode]
A glass substrate with ITO (manufactured by Geomatec) was ultrasonically cleaned using pure water, acetone and methanol in this order for 10 minutes each, and then dried. Thereafter, the ITO-attached glass substrate was subjected to UV ozone treatment for 20 minutes.

[Formation of electron transport layer]
A titanium isopropoxide ethanol solution adjusted to 2% by mass was applied onto the ITO-attached glass substrate by spin coating, and then baked at 400° C. for 10 minutes to form a thin-film electron transport layer with a thickness of 20 nm. Further, a titanium oxide paste containing polyisobutyl methacrylate as an organic binder, titanium oxide (average particle size: 25 nm), and ethanol was applied onto the thin-film electron-transporting layer by spin coating, and then heated at 500° C. for 10 minutes. It was baked to form a porous electron transport layer having a thickness of 500 nm.

[Formation of photoelectric conversion layer]
A photoelectric conversion layer coating solution was prepared by dissolving 4 g of lead iodide and 1.4 g of methylammonium iodide in 4.5 g of dimethylformamide as a solvent and stirring at 60° C. for 24 hours for dissolution. A photoelectric conversion layer having a thickness of 500 nm was formed by spin-coating this coating liquid on the electron transport layer. At this time, the maximum height Rz of the surface roughness of the photoelectric conversion layer was 270 nm.

[Formation of particle layer]
5 g of particles 1 in Table 1, 45 g of chlorobenzene, and 50 g of glass beads are enclosed in a glass bottle, dispersed for 6 hours using a paint shaker to prepare a particle layer coating solution, and spin-coated on the photoelectric conversion layer. A particle layer was formed with only particles having a thickness of 100 nm.

[Introduction of charge-transporting material into particle layer]
Spiro-OMeTAD (180 mg) as a charge transport material was dissolved in chlorobenzene (1 mL). To this chlorobenzene solution, an acetonitrile solution (37.5 μL) obtained by dissolving lithium-bis(trifluoromethanesulfonyl)imide (170 mg) in acetonitrile (1 mL) and t-butylpyridine (TBP, 17.5 μL) were added. mixed to prepare a charge transport material solution. This was applied onto the particle layer formed of only the above particles by a spin coating method to form a particle layer with a total thickness of 200 nm in which the particles were covered with the charge transport material.

[Formation of first electrode]
A gold electrode having a thickness of 80 nm and an area of 0.09 cm ² was formed on the particle layer by vacuum evaporation to obtain a photoelectric conversion element.

(Example 2)
A photoelectric conversion element was obtained in the same manner as in Example 1 except that Particles 4 were used as particles mainly composed of a phthalocyanine compound, and a particle layer having a thickness of 700 nm was formed only with particles without using a charge transporting material.

(Example 3)
A photoelectric conversion device was obtained in the same manner as in Example 2, except that Particles 10 were used as particles mainly composed of a phthalocyanine compound.

(Example 4)
A photoelectric conversion element was obtained in the same manner as in Example 3, except that the maximum height Rz of the surface roughness of the photoelectric conversion layer was 190 nm.

(Example 5)
A photoelectric conversion element was obtained in the same manner as in Example 3, except that the maximum height Rz of the surface roughness of the photoelectric conversion layer was 300 nm.

(Example 6)
A photoelectric conversion device was obtained in the same manner as in Example 2, except that Particles 3 were used as particles mainly composed of a phthalocyanine compound.

(Example 7)
A photoelectric conversion device was obtained in the same manner as in Example 2, except that Particles 9 were used as particles mainly composed of a phthalocyanine compound.

(Example 8)
A photoelectric conversion device was obtained in the same manner as in Example 2, except that Particles 8 were used as particles mainly composed of a phthalocyanine compound.

(Example 9)
A photoelectric conversion device was obtained in the same manner as in Example 2, except that Particles 2 were used as particles mainly composed of a phthalocyanine compound.

(Example 10)
A photoelectric conversion device was obtained in the same manner as in Example 2, except that Particles 5 were used as particles mainly composed of a phthalocyanine compound.

(Example 11)
A photoelectric conversion element was obtained in the same manner as in Example 2, except that after forming a particle layer of only particles in the same manner as in Example 1, a charge transporting material was introduced to form a particle layer. The thickness of the entire particle layer was made 100 nm thicker than the thickness of the particles alone.

(Example 12)
A photoelectric conversion device was obtained in the same manner as in Example 2, except that the particle layer thickness was changed to 500 nm.

(Example 13)
A photoelectric conversion device was obtained in the same manner as in Example 2, except that the particle layer thickness was set to 40 nm and Particles 5 were used as particles mainly composed of a phthalocyanine compound.

(Example 14)
A photoelectric conversion device was obtained in the same manner as in Example 2, except that Particles 6 were used as particles mainly composed of a phthalocyanine compound.

(Example 15)
A photoelectric conversion device was obtained in the same manner as in Example 2 except that Particles 7 were used as particles mainly composed of a phthalocyanine compound.

(Example 16)
A photoelectric conversion element was obtained in the same manner as in Example 2, except that the particle layer thickness was changed to 400 nm.

(Example 17)
A photoelectric conversion device was obtained in the same manner as in Example 9, except that after forming a particle layer of only particles in the same manner as in Example 1, a charge transporting material was introduced to form a particle layer. The thickness of the entire particle layer was made 100 nm thicker than the thickness of the particles alone.

(Example 18)
A photoelectric conversion device was obtained in the same manner as in Example 9, except that the particle layer thickness was changed to 200 nm.

(Example 19)
A photoelectric conversion element was obtained in the same manner as in Example 18, except that after forming a particle layer of only particles in the same manner as in Example 1, a charge transporting material was introduced to form a particle layer. The thickness of the entire particle layer was made 100 nm thicker than the thickness of the particles alone.

(Example 20)
[Washing of substrate]
The glass substrate was ultrasonically cleaned using pure water, acetone and methanol in this order for 10 minutes each, and then dried.

[Formation of second electrode]
An Al electrode having a thickness of 1000 nm was formed on the glass substrate by a vacuum deposition method.

[Formation of electron transport layer]
A tin oxide dispersed water colloidal solution (manufactured by Alfa Aesar) was spin-coated on the Al electrode and dried at 150° C. for 30 minutes to form an electron transport layer having a thickness of 50 nm.

[Formation of photoelectric conversion layer and particle layer]
It was carried out in the same manner as in Example 1.

[Formation of first electrode]
Using an ITO target doped with 5% by mass of tin on the particle layer, using an Ar gas containing O ₂ (5 mol%), a sputtering method was performed under the conditions of a pressure of 0.5 Pa to a thickness of 150 nm and an area of 150 nm. A 0.09 cm ² ITO electrode was formed.

(Example 21)
A photoelectric conversion device was obtained in the same manner as in Example 1 except that Particles 11 were used as particles mainly composed of a phthalocyanine compound.

(Example 22)
A photoelectric conversion device was obtained in the same manner as in Example 1, except that Particles 12 were used as particles mainly composed of a phthalocyanine compound.

(Example 23)
A photoelectric conversion device was obtained in the same manner as in Example 1, except that Particles 13 were used as particles mainly composed of a phthalocyanine compound.

(Example 24)
A photoelectric conversion device was obtained in the same manner as in Example 1 except that Particles 14 were used as particles mainly composed of a phthalocyanine compound.

(Example 25)
A photoelectric conversion device was obtained in the same manner as in Example 1 except that Particles 15 were used as particles mainly composed of a phthalocyanine compound.

(Example 26)
A photoelectric conversion device was obtained in the same manner as in Example 1 except that Particles 16 were used as particles mainly composed of a phthalocyanine compound.

(Comparative example 1)
[Washing of substrate and second electrode]
It was carried out in the same manner as in Example 1.

[Formation of injection layer]
A LiF film having a thickness of 0.5 nm was formed on the second electrode by a vacuum deposition method.

[Formation of Bulk Heterolayer]
1 g of poly(3-hexylthiophene), 1 g of fullerene derivative (PCBM: Phenyl-C61-Butyric-Acid-Methyl Ester), 8 g of Particle 1, and 15 g of chlorobenzene were dissolved and dispersed to prepare a bulk heterolayer coating liquid. did. A bulk hetero layer having a thickness of 300 nm was formed by spin-coating the coating solution on the injection layer.

[Formation of first electrode]
It was carried out in the same manner as in Example 1.

(Comparative example 2)
[Washing of substrate]
The titanium substrate was ultrasonically cleaned using pure water, acetone and methanol in this order for 10 minutes each, and then dried.

[Formation of second electrode]
It was carried out in the same manner as in Example 20.

[Formation of electron transport layer and photoelectric conversion layer]
It was carried out in the same manner as in Example 1.

[Formation of charge transport layer]
1 g of Phthalocyanine (purified by sublimation) [for organic electronics] (manufactured by TCI) was dissolved in 9 g of chlorobenzene to prepare a coating liquid for charge transport layer. A charge transport layer having a thickness of 100 nm was formed by spin-coating the coating liquid onto the photoelectric conversion layer.

[Formation of first electrode]
It was carried out in the same manner as in Example 20.

<Evaluation>
The photoelectric conversion elements obtained in Examples and Comparative Examples were evaluated as follows.

(Evaluation of power generation efficiency)
A power supply (236 model manufactured by KEITHLEY) is connected between the electrodes of the photoelectric conversion element, and a constant light is irradiated using a solar simulator (manufactured by Yamashita Denso) with an intensity of 100 mW/cm ² to generate current and voltage. The photoelectric conversion efficiency was evaluated by measuring . Table 2 shows the results.

1, 31, 41: photoelectric conversion element, 2: substrate, 3: second electrode, 5: photoelectric conversion layer, 6: particle layer, 7: first electrode, 30: moving object, 32: fuselage, 40: building material, 42: Protective member, 43: Heat radiating member

Claims (15)

A photoelectric conversion element having a first electrode, a second electrode, and a photoelectric conversion layer containing an organic-inorganic perovskite compound disposed between the first electrode and the second electrode,
A photoelectric conversion element comprising a particle layer composed of particles mainly composed of a phthalocyanine compound between the photoelectric conversion layer and the first electrode. 2. The photoelectric conversion device according to claim 1, wherein the average particle size of the particles is smaller than the maximum height Rz of the surface roughness of the photoelectric conversion layer. 3. The photoelectric conversion element according to claim 1, wherein the particles have an average particle size of 300 nm or less. 4. The photoelectric conversion device according to claim 1, wherein the particles have an average particle size of 20 nm or more. 5. The photoelectric conversion device according to claim 1, wherein the particle layer comprises the particles and a charge transport material. 6. The photoelectric conversion device according to claim 1, wherein the particle layer has a film thickness of 20 nm or more and 800 nm or less. 6. The photoelectric conversion device according to claim 1, wherein the particle layer has a film thickness of 50 nm or more and 400 nm or less. The particles are crystal particles of a crystalline phthalocyanine compound exhibiting peaks at Bragg angles 2θ of 7.4°±0.3° and 28.2°±0.3° in an X-ray diffraction spectrum using CuKα rays. 8. The photoelectric conversion element according to any one of claims 1 to 7, comprising: The particles include crystal particles of a phthalocyanine compound having a peak at 20 nm or more and 50 nm or less in a crystal particle size distribution measured using small-angle X-ray scattering and a half width of the peak of 50 nm or less. The photoelectric conversion device according to any one of claims 1 to 8. 10. The photoelectric conversion device according to claim 1, wherein the particles contain the phthalocyanine compound in an elemental analysis ratio of 80% by mass or more and 99% by mass or less. A photoelectric conversion module comprising a plurality of photoelectric conversion elements according to claim 1 . A photoelectric conversion device comprising: the photoelectric conversion element according to claim 1 ; and a power storage unit connected to the photoelectric conversion element. A photoelectric conversion device comprising: the photoelectric conversion element according to claim 1 ; and an inverter connected to the photoelectric conversion element. A moving object comprising: the photoelectric conversion element according to any one of claims 1 to 10; and a body provided with the photoelectric conversion element. A building material comprising: the photoelectric conversion element according to any one of claims 1 to 10; a protective member for protecting the photoelectric conversion element; and a heat radiating member.

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