Fluorinated graphdiyne as a significantly enhanced fluorescence material

The chemical modification of graphdiyne (GDY) using light elements is a possible route to regulate its unique structure and optoelectronic properties. In this paper it is shown that directly heating a mixture of xenon difluoride and GDY produces partially fluorinated GDY with covalent C-F bonding and localized sp²-carbon hybridization because of the breaking of the acetylenic bond. It is seen that the fluorescence of GDY is significantly enhanced because of the fluorine doping. All the fluorinated GDYs with different doping ratios of fluorine exhibit photoluminescence from bright blue to green when the excitation wavelength varies from 260 nm to 480 nm. In addition, the doped GDY with 15.2% fluorine doping shows a strong photoluminescence and the quantum efficiency is 3.7%. The enhanced fluorescence is considered to be induced by defect states because of the doping of fluorine, suggesting its potential applications in luminescence devices, such as biological sensing and flexible light-emitting diodes.