Study and Comparison on Purification Methods of Multicolor Emission Carbon Dots

Recent years have witnessed a rapid development of carbon dots (CDs), due to their outstanding luminescence properties and excellent biocompatibility. However, the internal structure and photoluminescent (PL) mechanism of CDs are still the subject of considerable debate, which is due to the fact that reaction products usually contain mixtures of several CD fractions as well as molecular intermediate and side products. Therefore, careful purification of the CDs is significant for analysis of structure and luminescence mechanism. Here, multicolor emission CDs were prepared by a one-pot pyrolysis of citric acid in formamide. Then, the precipitation method, dialysis and gel permeation chromatography (GPC) are successively employed to purify the multicolor emission CDs. This post-treatment allowed us to compare the optical properties of CDs obtained by different separation methods and provide a valuable guidance for the purification of CDs.

Automated summary

In this study, multicolor emission carbon dots were prepared by one-pot pyrolysis of citric acid in formamide, and then purified using precipitation method, dialysis, and gel permeation chromatography. By comparing the optical properties of carbon dots obtained by different separation methods, valuable guidance for the purification of carbon dots was provided.