▎ 摘　　要

NOVELTY - Graphene quantum dot composite comprises a dielectric matrix comprising a metal oxynitride, and graphene quantum dots dispersed in the dielectric matrix. USE - The composite is useful in an electroluminescent device (claimed), and for electronic and optical devices including electroluminescent devices, color conversion films, lighting equipment and flexible display devices. ADVANTAGE - The composite suppresses quenching caused by aggregation of graphene quantum dots, improves quantum efficiency of graphene quantum dots, and maintains stability of light emitting material of LED. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) a method for producing graphene quantum dot composite, involving preparing a mixed solution containing nitrogen-containing hydride and metal hydroxide, reacting the nitrogen-containing hydride with the metal hydroxide to include a metal oxynitride, and forming a dielectric matrix in which the graphene quantum dots are dispersed; and (2) an electroluminescent device comprising lower electrode, an upper electrode spaced apart from the lower electrode, and a light emitting layer arranged between the lower electrode and the upper electrode, and comprising the graphene quantum dot composite.