A Chinese research team has developed organic solvents with specific structures which could be directly carbonized and form Graphene Quantum Dots (GQDs).

This work was jointly done by WANG Hui and LIN Wenchu with High Magnetic Field Laboratory, Hefei Institutes of Physical Science.

With tunable optical behavior, good chemical stability, and excellent biocompatibility, GQDs have been potential candidate for biomedical use.

"The bottom-up synthesis of GQDs using solvothermal method has always been the spotlight due to their fewer defects and controllable size/ morphology. However, we need to do more work to figure out the potential stability and decomposition possibility of organic solvents during the preparation of GQDs", said WANG Hui, who designed the project.

"We conducted a systematic study on the carbonization of organic solvents. And we found that the organic solvent with the double bond or benzene ring or double hydrophilic groups could be directly decomposed into GQDs with neither additional catalysts nor molecule precursors. The versatility of this synthetic strategy made it easy to control surface group, composition, and optical properties of GQDs at molecular level", explained Prof. LIN Wenchu, who did design and analysis work of their biological experiments.

The study was sponsored by the National Natural Science Foundation of China, the start-up fund of the Chinese Academy of Sciences (CAS), the Collaborative Innovation Program of Hefei Science Center of CAS, and the Science and Technology Major Project of Anhui Province. A portion of this work was supported by the High Magnetic Field Laboratory of Anhui Province.

Direct carbonization of organic solvent toward graphene quantum dots (Image by LIU Hongji)