Synthesis, properties, and applications of amphiphilic carbon dots: A review

With the development of nanotechnology, the synthesis, properties, and applications of nanomaterials have become one of the research hotspots. Carbon dots (CDs) have attracted significant attention from these nanomaterials due to their superior optical properties, low toxicity, and good biocompatibility. As a novel kind of zero-dimensional carbon nanomaterial with fluorescence emission functions, CDs have been applied in many fields, such as bioimaging, environmental detection, and drug delivery. CDs can be classified as hydrophilic, hydrophobic, or amphiphilic depending on their dispersibility in different solvents. Amphiphilic carbon dots (ACDs) are CDs that simultaneously possess hydrophilic and hydrophobic characteristics and can be well dispersed in both aqueous and organic solvents. Compared with hydrophilic or hydrophobic CDs, they exhibit unique properties, such as solvatochromism effects, surface/interfacial activity, and emulsifying properties. Recently, ACDs have shown great potential in fields such as cell imaging, luminescent materials, and enhanced oil recovery. In this review, we summarize the research progress of ACDs, including synthesis methods, properties, and applications. Finally, we discuss the unresolved issues of ACDs and look forward to future development directions.