Preparation of Fluorescent Carbon Dots from Chinese Herbal Medicine Alisma and Its Potential Applications in Photocatalytic Degradation of Malachite Green and Cell Imaging

N atural plants and Chinese herbal medicines are valuable resources. It is one of the new tasks for medical workers to study the new application fields of these resources. In this work, one kind of traditional Chinese herbal plant, Alisma, was chosen as a carbon source to synthesize the carbon dots(CDs). This kind of CDs has an amorphous carbon structure and shows strong stability to time, temperature, and ion strength. The results show that the degradation efficiency of malachite green dye can reach 100% in 4.5 h without illumination, and the degradation efficiency is better than that in dark environment. In addition, the CDs have also been successfully applied to HeLa cell imaging. Simple synthesis method, stable properties, good photodegradation and bioimaging applications make this material of great application value.