Abstract:Sulfur quantum dots are outstanding because of high luminous intensity, low toxicity and stable photochemical properties, and they are widely used in cell imaging, photoelectric conversion and chemical catalysis. Synthesis methods, optical properties and application background of sulfur quantum dots are systematically reviewed in this article. The synthesis method of sulfur quantum dots can be divided into "bottom-up method" and "top-down method", and the latter could afford sulfur quantum dots with higher fluorescence quantum yield than the former. It is reviewed that the optical properties of sulfur quantum dots. The characterization of optical properties shows that sulfur quantum dots possess ultraviolet absorption characteristics, fluorescence characteristics, Photoluminescence, electrochemiluminescence, and optical stability. Finally, it is introduced about the important application of sulfur quantum dots in the fields of fluorescent probes, biological imaging and light-emitting devices. Based on the above analysis, the problems are deeply discussed and need to be solved urgently in the cutting-edge application of sulfur quantum dots. Moreover, the future development direction of sulfur quantum dots is forecasted in new industries and fields such as biomedicine and photoelectric.