# US 12,604,601 B2 · Light-emitting element, quantum dot solution, and method for manufacturing light-emitting element > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,604,601 B2 - Document ID: US12604601B2 - Status: Granted - Kind: B2 - Application number: 18/287,538 - Filed: 2021-05-20 - Published: 2024-07-04 - Granted: 2026-04-14 - Earliest claimed: 2021-05-20 - Assignees: Sharp Kabushiki Kaisha - Applicants: Sharp Kabushiki Kaisha - Inventors: Keisuke Kitano; Kazuki Goto; Masaki Yamamoto - Web page: https://patentgrep.com/patent/US12604601B2 ## CPC - H10K 50/115: comprising active inorganic nanostructures, e.g. luminescent quantum dots - G09F 9/30: in which the desired character or characters are formed by combining individual elements (panels comprising a number of electrodes in a single cell controlling light arriving from an independent light source, e.g. electro-optical or magneto-optical cell, G02F1/00) - H05B 33/10: Apparatus or processes specially adapted to the manufacture of electroluminescent light sources - H05B 33/14: characterised by the chemical or physical composition or the arrangement of the electroluminescent material {, or by the simultaneous addition of the electroluminescent material in or onto the light source} - H10K 50/16: Electron transporting layers - H10K 59/131: Interconnections, e.g. wiring lines or terminals - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES - G09F: DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL ## Abstract A light-emitting element according to the disclosure includes a cathode, an anode, and a light-emitting layer provided between the cathode and the anode. The light-emitting layer includes a quantum dot, a plurality of first ions, and a plurality of second ions. Each of the first ions is an anion, and each of the second ions is a cation. The anion is any one of S2−, Se2−, and Te2−, and the cation is composed of a nonmetallic element. ## Claims ### Claim 1 A light-emitting element comprising: an anode; a cathode; and a light-emitting layer provided between the anode and the cathode, wherein the light-emitting layer includes a quantum dot, a plurality of first ions, and a plurality of second ions, each of the plurality of first ions is an anion and each of the plurality of second ions is a cation, the anion is any one of S2−, Se2−, and Te2−, and the cation is composed of a nonmetallic element. ### Claim 2 (depends on 1) The light-emitting element according to claim 1, wherein at least some of the plurality of first ions are coordinated to the quantum dot. ### Claim 3 (depends on 1) The light-emitting element according to claim 1, wherein the light-emitting layer includes a compound formed by bonding at least the some of the plurality of first ions and at least some of the plurality of second ions. ### Claim 4 (depends on 3) The light-emitting element according to claim 3, wherein the compound is a solid or a liquid at room temperature and becomes a gas by thermal decomposition. ### Claim 5 (depends on 1) The light-emitting element according to claim 1, wherein a substance constituting the quantum dot includes an element common to the anion. ### Claim 6 (depends on 1) The light-emitting element according to claim 1, wherein the cation is a monovalent ion including N or P and H as elements. ### Claim 7 (depends on 1) The light-emitting element according to claim 1, further comprising: an electron transport layer including ZnO, wherein the light-emitting layer is formed on the electron transport layer. ### Claim 8 (depends on 7) The light-emitting element according to claim 7, wherein the electron transport layer is disposed between the cathode and the light-emitting layer. ### Claim 9 (depends on 1) The light-emitting element according to claim 1, wherein a concentration of the anion is higher in a cathode-side portion of the light-emitting layer than in an anode-side portion of the light-emitting layer. ### Claim 10 (depends on 1) The light-emitting element according to claim 1, wherein the cation is any one of an ammonium ion, an imidazole ion, and a phosphonium ion. ### Claim 11 (depends on 1) The light-emitting element according to claim 1, wherein a decrease in external quantum efficiency with respect to light emission for 200 hours at a constant current of 10 mA/cm2 is 5% or less. ### Claim 12 (depends on 1) A display device comprising: the light-emitting element according to claim 1. ### Claim 13 A light-emitting element comprising: an anode; a cathode; and a light-emitting layer provided between the anode and the cathode, wherein the light-emitting layer includes a quantum dot and a capping agent, the capping agent is composed of a compound formed by bonding a cation and an anion, the anion is any one of S2−, Se2−, and Te2−, and the cation is composed of a nonmetallic element. ### Claim 14 A quantum dot solution comprising: a solvent; a quantum dot; a plurality of first ions; and a plurality of second ions, wherein each of the plurality of first ions is an anion and each of the plurality of second ions is a cation, the anion is any one of S2−, Se2−, and Te2−, and the cation is composed of a nonmetallic element. ### Claim 15 (depends on 13) The quantum dot solution according to claim 13, wherein at least some of the plurality of first ions are coordinated to the quantum dot. ### Claim 16 (depends on 14) The quantum dot solution according to claim 14, wherein a substance formed by bonding the cation and the anion is a solid or a liquid at normal temperature and normal pressure, and is thermally decomposed to become a gas by heating at a predetermined temperature higher than normal temperature. ### Claim 17 (depends on 16) The quantum dot solution according to claim 16, wherein the predetermined temperature is from 100 to 130 degrees. ### Claim 18 (depends on 14) The quantum dot solution according to claim 14, wherein the cation is a monovalent ion including N or P and H as elements. ### Claim 19 (depends on 14) The quantum dot solution according to claim 14, wherein the cation is any one of an ammonium ion, an imidazole ion, and a phosphonium ion. ### Claim 20 (depends on 14) The quantum dot solution according to claim 14, wherein a mass ratio of the cation to a material of the quantum dot is 0.9 or more.