Interaction of Graphene Quantum Dots with Bulk Semiconductor Surfaces

摘要

Highly luminescent graphene quantum dots (GQDs) are synthesized through thermolysis of glucose. The average lateral size of the synthesized GQDs is found to be ～5 nm. The occurrence of D and G band at 1345 and 1580 cm~(-1) in Raman spectrum confirms the presence of graphene layers. GQDs are mostly consisting of 3 to 4 graphene layers as confirmed from the AFM measurements. Photoluminescence (PL) measurement shows a distinct broadening of the spectrum when GQDs are on the semiconducting bulk surface compared to GQDs in water. The time resolved PL measurement shows a significant shortening in PL lifetime due to the substrate interaction on GQDs compared to the GQDs in solution phase.