▎ 摘　　要

NOVELTY - Preparing composite material involves obtaining water-soluble graphene quantum dot through an electrochemical method. Poly(4-vinylphenol) (5-10%) and crosslinking agent (poly(melamine-co-formaldehyde)) (2%) are mixed in an organic solvent to obtain solution. Graphene quantum dot is mixed with obtained solution to obtain graphene quantum dots containing poly(4-vinylphenol) composites solution. Graphene quantum dots containing poly(4-vinylphenol) composites solution is stirred at rotational speed of 2000-6000 rotations per minute. USE - Method for preparing composite material (claimed) used in memory device. ADVANTAGE - The method enables to prepare highly stable composite material in simple manner. DETAILED DESCRIPTION - Preparing composite material involves obtaining water-soluble graphene quantum dot through an electrochemical method. Poly(4-vinylphenol) (5-10%) and crosslinking agent poly(melamine-co-formaldehyde) (2%) are mixed in an organic solvent to obtain solution. Graphene quantum dot is mixed with obtained solution to obtain graphene quantum dots containing poly(4-vinylphenol) composites solution. Graphene quantum dots containing poly(4-vinylphenol) composites solution is stirred at rotational speed of 2000-6000 rotations per minute. Solid substrate is placed into graphene quantum dots containing poly(4-vinylphenol) composites solution. Spin coating is performed at the solid substrate surface for 30-60 seconds, and then stirred at rotational speed 2000-6000 rotations per minute for 20-60 minutes.