S, N co-doped graphene quantum dots fabricated by rapid microwave-assisted pyrolysis and their optical properties

Recently, graphene quantum dots (GQDs) have attracted the interest of scientists as a potential material for applications in antibacterial agents. Besides, low-cost synthesis, environmentally friendly, safe in use, easy-toperform technique is one of the urgent requirements to apply this material. This research presents the synthesis of sulfur (S) and nitrogen (N) co-doped GQDs (S,N-GQDs) by microwave-assisted pyrolysis, which is a rapid, simple, and green method, as well as improved their dispersion in water for antibacterial purposes. The particle size of fabricated S,N-GQDs was 3 nm. XRD patterns reveal that S,N-GQDs have a crystalline structure with a carbogenic core. Both the S pi* -* C pi and N pi* -* C pi transitions contribute to the luminescence of the S,N-GQDs material, whose local luminescence peaks at 448 nm, this peak changed with various pH values. High quantum yield depends on both the power of microwave and pH values.

Automated summary

This study presents the synthesis of sulfur and nitrogen co-doped graphene quantum dots (S,N-GQDs) using microwave-assisted pyrolysis and improves their dispersion in water for antibacterial purposes. The fabricated S,N-GQDs have a carbogenic core structure and the luminescence of the material is pH-dependent.