Nitrogen-containing graphene structure and phosphor dispersion

A nitrogen-containing graphene structure, comprising:

• a graphene structure having a sheet portion comprised of a monolayer or multilayer graphene nanosheet;
• and
• nitrogen introduced into the graphene structure,
• wherein:
• the sheet portion comprises, at an edge portion thereof, an armchair edge-face portion and a terminal six-membered ring bound to the armchair edge-face portion while sharing only one side therewith,
• the nitrogen comprises nitrogen introduced into the graphene structure in the form of one or more amino groups and amide groups bound to one or more carbon atoms selected from:
• (a) carbon atoms constituting the terminal six-membered ring but not bound to the armchair edge-face portion, and
• (b) carbon atoms constituting the sheet portion including the carbon atom on the side shared with the terminal six-membered ring,
• the nitrogen-containing graphene structure has an average mass of 1000 m/z to 50000 m/z,
• the nitrogen-containing graphene structure has a nitrogen content of 5 wt % to 50 wt %, and
• the nitrogen-containing graphene structure emits light and has an emission efficiency of 15% or greater.