Promising Fast Energy Transfer System Between Graphene Quantum Dots and the Application in Fluorescent Bioimaging.

Tunable photoluminescence performance of graphene quantum dots (GQDs) is one of the most important topics for the development of GQDs. In this paper, we report lattice-doped GQDs (boron-doped GQDs (B-GQDs) and phosphorus-doped GQDs (P-GQDs)). Because of the matched band structure, the fast energy transfer between blue-emitted B-GQDs (emission wavelength: 460 nm) and orange-emitted P-GQDs (emission wavelength: 630 nm) can induce an efficient fluorescence emission in P-GQDs once B-GQDs are excited under the optimal excitation wavelength of 460 nm. Moreover, with the effective energy transfer, the quantum yield of P-GQDs increased to 0.48, which is much higher than that of pure P-GQDs. We also demonstrated the potentials of this system for fluorescent bioimaging in vitro.