# US 12,006,457 B2 · Graphene quantum dot composite with dielectric matrix, electroluminescent device having the same, and method for manufacturing the graphene quantum dot composite > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,006,457 B2 - Document ID: US12006457B2 - Status: Granted - Kind: B2 - Application number: 17/290,795 - Filed: 2019-10-31 - Published: 2021-12-30 - Granted: 2024-06-11 - Earliest claimed: 2018-12-20 - Assignees: Korea Advanced Institute of Science and Technology - Applicants: Korea Advanced Institute of Science and Technology - Inventors: Seokwoo Jeon; Minsu Park; Hyewon Yoon - Web page: https://patentgrep.com/patent/US12006457B2 ## CPC - C09K 11/02: Use of particular materials as binders, particle coatings or suspension media therefor - C09K 11/65: containing carbon (in organic compounds C09K11/06) - 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} - H05B 33/20: characterised by the chemical or physical composition or the arrangement of the material in which the electroluminescent material is embedded - H10K 50/115: comprising active inorganic nanostructures, e.g. luminescent quantum dots - B82Y 20/00: Nanooptics, e.g. quantum optics or photonic crystals - B82Y 40/00: Manufacture or treatment of nanostructures - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - H05B: ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL - H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES - B82Y: SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES ## Abstract The disclosed graphene quantum dot composite includes a dielectric matrix including a metal oxynitride, and a graphene quantum dot dispersed in the dielectric matrix. The graphene quantum dot composite can reduce the aggregation-caused photoluminescence quenching of graphene quantum dots, and can improve a photoluminescence quantum yields of a graphene quantum dot. ## Claims ### Claim 1 A graphene quantum dot composite comprising: a dielectric matrix including a metal oxynitride; and a graphene quantum dot dispersed in the dielectric matrix. ### Claim 2 (depends on 1) The graphene quantum dot composite of claim 1, wherein the metal oxynitride includes at least one selected from the group consisting of boron, aluminum, gold, gallium, yttrium, indium, scandium, cobalt, iridium, ruthenium, chromium, iron, zirconium, titanium, hafnium, silicon, tungsten, cerium, osmium, vanadium, niobium, tantalum and molybdenum. ### Claim 3 (depends on 1) The graphene quantum dot composite of claim 1, wherein the metal oxynitride includes boron oxynitride. ### Claim 4 (depends on 1) The graphene quantum dot composite of claim 1, wherein a content of the graphene quantum dot is 0.01 to 1 wt %. ### Claim 5 (depends on 1) The graphene quantum dot composite of claim 1, wherein the graphene quantum dot has a powder shape, and has an average particle size of 100 μm or less. ### Claim 6 (depends on 1) The graphene quantum dot composite of claim 1, wherein a distance between graphene quantum dots adjacent to each other in the graphene quantum dot composite is 4 nm or more. ### Claim 7 (depends on 1) The graphene quantum dot composite of claim 1, wherein the graphene quantum dot has a carbonyl group (C═O) or a hydroxyl group (—OH), which bonded to a surface thereof. ### Claim 8 A method for manufacturing a graphene quantum dot composite, the method comprising: preparing a mixture solution including a graphene quantum dot, a nitrogen-containing hydride and a metal hydroxide; and reacting the nitrogen-containing hydride and the metal hydroxide with each other to form a dielectric matrix including a metal oxynitride and dispersing the graphene quantum dot therein. ### Claim 9 (depends on 8) The method of claim 8, wherein the nitrogen-containing hydride have at least one bond of C═O, C═S, C═Se and C═N. ### Claim 10 (depends on 9) The method of claim 9, wherein the nitrogen-containing hydride includes at least one selected from the group consisting of hydrogen cyanide, sodium cyanide, potassium cyanide, calcium cyanide, mercury cyanide, sodium nitroprussiate, acetonitrile, cyanogen chloride, cyanogen bromide, cyanogen fluoride, carbonyldiamine, carbonyldiimidazole, carbamoyl phosphate, cyanamide, sodium dicyanamide, malononitrile, valeronitrile, methyl isocyanate, methyl cyanoacrylate, methyl ferrocyanide, ethyl isocyanate, ethyl cyanoacrylate, ethyl ferrocyanide, propyl isocyanate, propyl cyanoacrylate, propyl ferrocyanide, butyl isocyanate, butyl cyanoacrylate, butyl ferrocyanide, pentyl isocyanate, pentyl cyanoacrylate, pentyl ferrocyanide, hexyl isocyanate, hexyl cyanoacrylate, hexyl ferrocyanide, butyl cyanoacetate, allyl cyanoacetate, 3-aminocrotononitrile, 2-methylbutyronitrile, 2-methoxyethyl cyanoacetate, thiosemicarbazide, dithiooxamide, thioacetamide, ethyl thiooxamate, 2-methyl-3-thiosemicarbazide, 4-methyl-3-thiosemicarbazide, 2-cyanothioacetamide, 4,4-dimethyl-3-thiosemicarbazide, 4-ethyl-3-thiosemicarbazide, 2-bromothiobenzamide, 3-bromothiobenzamide, 4-bromothiobenzamide, 4-chlorothiobenzamide, thiobenzamide, 4-methylbenzenethioamide, selenourea, selenoformamide, selenoacetamide, selenobenzamide and urea. ### Claim 11 (depends on 8) The method of claim 8, wherein the metal hydroxide includes at least one selected from the group consisting of boron hydroxide, aluminum hydroxide, gold hydroxide, gallium hydroxide, yttrium hydroxide, indium hydroxide, scandium hydroxide, cobalt hydroxide, iridium hydroxide, ruthenium hydroxide, chromium hydroxide, iron hydroxide, zirconium hydroxide, titanium hydroxide, hafnium hydroxide, silicon hydroxide, tungsten hydroxide, cerium hydroxide, osmium hydroxide, vanadium hydroxide, niobium hydroxide, tantalum hydroxide and molybdenum hydroxide. ### Claim 12 (depends on 8) The method of claim 8, wherein reacting the nitrogen-containing hydride and the metal hydroxide with each other is performed through electromagnetic wave treatment, heating, vacuum heating or drying. ### Claim 13 (depends on 8) The method of claim 8, further comprising grinding the graphene quantum dot composite to form a powder having an average particle size of 100 μm or less. ### Claim 14 An electroluminescent device comprising: a lower electrode; an upper electrode spaced apart from the lower electrode; and a light-emitting layer disposed between the lower electrode and the upper electrode and including a graphene quantum dot composite, wherein the graphene quantum dot composite includes: a dielectric matrix including a metal oxynitride; and a graphene quantum dot dispersed in the dielectric matrix. ### Claim 15 (depends on 14) The electroluminescent device of claim 14, wherein the metal oxynitride includes boron oxynitride, and a distance between graphene quantum dots adjacent to each other in the graphene quantum dot composite is 4 nm or more. ### Claim 16 (depends on 14) The electroluminescent device of claim 14, further comprising a dielectric layer disposed between the light-emitting layer and at least one of the lower electrode and the upper electrode, and wherein the light-emitting layer is configured to emit a light by an alternating-current (AC) electric field.