# US 12,120,891 B2 · Photoelectric conversion element, photoelectric conversion device, photoelectric conversion element precursor, light detection method, and production method for photoelectric conversion element > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,120,891 B2 - Document ID: US12120891B2 - Status: Granted - Kind: B2 - Application number: 17/422,550 - Filed: 2020-01-30 - Published: 2022-03-31 - Granted: 2024-10-15 - Earliest claimed: 2019-02-08 - Assignees: Japan Science and Technology Agency - Applicants: Japan Science and Technology Agency - Inventors: Ayumi Nihei; Tsutomu Miyasaka - Web page: https://patentgrep.com/patent/US12120891B2 ## CPC - H10K 30/151: {the wide bandgap semiconductor comprising titanium oxide, e.g. TiO2} - H10K 30/81: Electrodes - H10K 71/12: using liquid deposition, e.g. spin coating - H10K 85/351: {Metal complexes comprising lanthanides or actinides, e.g. comprising europium} - H10K 85/50: Organic perovskites; Hybrid organic-inorganic perovskites [HOIP], e.g. CH3NH3PbI3 - H10K 30/50: Photovoltaic [PV] devices - H10K 85/331: {Metal complexes comprising an iron-series metal, e.g. Fe, Co, Ni} - Y02E 10/549: Organic PV cells - Y02P 70/50: Manufacturing or production processes characterised by the final manufactured product - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION - Y02P: CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS ## Abstract A photoelectric conversion element includes a first layer, a second layer, and a third layer that are laminated in this order. The first layer is formed of a plurality of particles including an inorganic semiconductor as a main component, an aggregate of the particles, or a thin film including an inorganic semiconductor as a main component. The second layer is provided on a surface of each of the particles or the aggregate and is formed of a plurality of particles including a perovskite structure as a main component, an aggregate of the particles, or a thin film including a perovskite structure as a main component. The third layer is formed of a plurality of particles including an organic metal complex as a main component, an aggregate of the particles, or a thin film including an organic metal complex as a main component. ## Claims ### Claim 1 A photoelectric conversion element comprising a first layer, a second layer, and a third layer that are laminated in this order, wherein the first layer is formed of a plurality of particles including an inorganic semiconductor as a main component, an aggregate of the particles, or a thin film including an inorganic semiconductor as a main component, the second layer is provided on a surface of each of the particles or the aggregate and is formed of a plurality of particles including a perovskite structure as a main component, an aggregate of the particles, or a thin film including a perovskite structure as a main component, the third layer is formed of a plurality of particles including an organic metal complex as a main component, an aggregate of the particles, or a thin film including an organic metal complex as a main component, in a conduction band, an energy level of the second layer is higher than an energy level of the first layer and an energy level of the third layer is higher than the energy level of the second layer, in a valence band, an energy level of the second layer is higher than an energy level of the third layer, wherein the organic metal complex is a complex obtained by forming a coordinate bond between an inorganic transition metal and an organic ligand, and wherein the inorganic transition metal is localized on the second layer side. ### Claim 2 (depends on 1) The photoelectric conversion element according to claim 1, wherein the second layer is a layer in which an energy difference between the valence band and the conduction band is lower than 3.1 eV. ### Claim 3 (depends on 1) The photoelectric conversion element according to claim 1, wherein the first layer and/or the third layer is a layer in which an energy difference between the valence band and the conduction band is 3.1 eV or higher. ### Claim 4 (depends on 1) The photoelectric conversion element according to claim 1, wherein in the valence band, an energy level difference between the second layer and the third layer is 0.1 eV or higher. ### Claim 5 (depends on 1) The photoelectric conversion element according to claim 1, wherein the organic ligand is a ring heteroatom-containing organic ligand or an acetylacetonate-based organic ligand. ### Claim 6 (depends on 1) The photoelectric conversion element according to claim 1, wherein the organic metal complex is a complex obtained by forming a coordinate bond between an inorganic transition metal and a nonbonding electron pair of ring heteroatoms in a ring heteroatom-containing organic ligand. ### Claim 7 (depends on 5) The photoelectric conversion element according to claim 5, wherein the inorganic transition metal is europium, and the ring heteroatom-containing organic ligand is terpyridine. ### Claim 8 (depends on 1) The photoelectric conversion element according to claim 1, wherein the inorganic semiconductor is an inorganic semiconductor having an absorption wavelength in an ultraviolet range. ### Claim 9 (depends on 1) The photoelectric conversion element according to claim 1, wherein the inorganic semiconductor is titanium oxide. ### Claim 10 (depends on 1) The photoelectric conversion element according to claim 1, wherein the second layer is a thin film, particles, or an aggregate of the particles having a thickness of 1 nm or more and 10 nm or less. ### Claim 11 (depends on 1) The photoelectric conversion element according to claim 1, wherein the perovskite structure is a compound represented by a compositional formula CH3NH3PbI3. ### Claim 12 (depends on 1) The photoelectric conversion element according to claim 1, wherein the first layer is a layer having an energy level of −8 eV or higher in the valence band and having an energy level of −4 eV or lower in the conduction band. ### Claim 13 (depends on 1) The photoelectric conversion element according to claim 1, wherein the second layer is a layer having an energy level of −5.5 eV or higher in the valence band and having an energy level of −3 eV or lower in the conduction band. ### Claim 14 (depends on 1) The photoelectric conversion element according to claim 1, wherein the third layer is a layer having an energy level of −6 eV or higher in the valence band and having an energy level of −2 eV or lower in the conduction band. ### Claim 15 (depends on 1) A photoelectric conversion device comprising the photoelectric conversion element according to claim 1, wherein a negative electrode layer is laminated on a side opposite to the second layer across the first layer, and a positive electrode layer is laminated on a side opposite to the second layer across the third layer. ### Claim 16 (depends on 15) A light detection method comprising a step of detecting visible light and/or near infrared light from measurement result of a current flowing by making the second layer in the photoelectric conversion device according to claim 15 to receive visible light and/or near infrared light when a voltage is applied between the negative electrode layer and the positive electrode layer. ### Claim 17 (depends on 1) A production method for the photoelectric conversion element according to claim 1, the production method comprising: a first step of forming a first laminate in which a first layer that is formed of a plurality of particles including an inorganic semiconductor as a main component, an aggregate of the particles, or a thin film including an inorganic semiconductor as a main component is laminated, on a surface of a substrate; a second step of forming a second laminate in which a second layer that is formed of a plurality of particles including a perovskite structure as a main component, an aggregate of the particles, or a thin film including a perovskite structure as a main component is laminated, on an exposed surface of the first layer, and a third step of forming a third laminate in which a third layer that is formed of a plurality of particles including an organic metal complex as a main component, an aggregate of the particles, or a thin film including an organic metal complex as a main component is laminated, on an exposed surface of the second layer, wherein energy levels of the respective layers in a conduction band are higher in order of the first layer, the second layer, and the third layer, and an energy level of the second layer is higher than an energy level of the third layer in the valence bands of the respective layers, wherein the third step includes a step of forming a layer that is formed of a plurality of particles including an inorganic transition metal as a main component, an aggregate of the particles, or a thin film including an inorganic transition metal as a main component on the exposed surface of the second layer and subsequently forming a coordinate bond between the inorganic transition metal in the layer and an organic ligand.