Quantization of Energy Gap of Nitrogen Doped Graphene Quantum Dots
Keywords:graphene quantum dots, hydrothermal, band gap
The outstanding photoluminescence (PL) properties of graphene quantum dots (GQDs) had attracted great interest in optical applications such as fluorescent imaging. In this work, a facile one-step hydrothermal method was used to synthesize nitrogen doped GQDs (N-GQDs) with a Teflon-lined autoclave heated at 180°C for 8 hours. High crystallinity was discovered in the purified N-GQDs with a lattice spacing of 0.21 nm corresponding to in-plane graphene (100 facet). From Tauc plot, the optical band gap of N-GQDs was estimated, derived from their UV-vis absorption spectrum. The as prepared N-GQDs are strongly fluorescent and highly soluble in aqueous solution. Due to the cheap material source, this synthesis provides a feasible route towards the commercial synthesis of N-GQDs. Thus, provides an effective strategy studies of electron transfer and to engineer the optical properties of GQDs.