▎ 摘　　要

Herein we selectively deactivate the ketonic carbonyl, carboxylic, or hydroxyl groups on GQDs and compare the ROS generation ability of different GQD derivatives. The results indicate that the ROS generation ability of GQDs is closely related to the ketonic carbonyl groups. Removal of the oxygen functional groups on GQDs can increase the photostability and lower the photoinduced cytotoxicity.