Synthesis and Characterization of Red‐Luminescent Graphene Oxide Functionalized with Silica‐Coated Eu 3+ Complex Nanoparticles

Traditional dye‐doped fluorescent graphene oxide (GO) reveals a low quantum yield and a short life expectancy. Herein, red‐luminescent silica‐coated Eu 3+ complex nanoparticles were synthesized and covalently coupled to GO nanosheets by means of a carbodiimide‐mediated amidation process. SEM and TEM studies demonstrated successful attachment of the silica‐coated Eu 3+ complex nanoparticles onto the GO surface. Spectroscopic studies showed that the GO–nanoparticle conjugates exhibit strong luminescence, long lifetimes, as well as good photostability, which suggests that this new type of luminescent nanomaterial has the potential for highly sensitive time‐resolved fluorescence cyto‐ and histochemistry imaging.