Graphene Quantum Dots as Fluorescence Probes for Sensing Metal Ions: Synthesis and Applications

This review focuses on the recent development of graphene quantum dots (GQDs) as fluorescence probes, including their synthesis and application in metal ions detection. Because of the quantum confinement and edge effects, GQDs have exhibited unusual optical and chemical properties. Recently, various studies have been performed to tune the fluorescent properties of graphene quantum dots through doping heteroatom to the pi-conjugated system or surface-functionalization. Herein, we summarize the fundamental optical properties of GQDs influenced by size/shape, zigzag site and defect density, which is of very importance for the development of novel nanodevices with novel properties. We then highlight the application of graphene quantum dot probes in fluorescent sensing of metal irons. We also discuss the current challenges and application prospects of fluorescent GQDs in metal ions sensor field.