Quantum dots are artificial materials at the nanoscale, typically ranging in size from 1 to 10 nanometers. It is a small and exquisite semiconductor particle, wrapped in a semiconductor layer with atomic thickness, and its surface is modified into an active surface that can fully react.

Quantum dots are a special type of material with the following types:

Semiconductor quantum dots: Due to their narrower bandwidth and strong quantum confinement effects, electrons in semiconductor quantum dots are confined within a spatial range, resulting in band discretization. Semiconductor quantum dots can emit visible or ultraviolet light, and the spectral range can be adjusted by their particle size. At present, semiconductor quantum dots such as CdSe, CdS, ZnS, InP, InAs have been prepared.

Metal quantum dots: Metal quantum dots generally refer to nanoparticles composed of metal elements. Metal quantum dots have high surface energy, with the smallest being single atoms, thus possessing excellent physical and chemical properties and unique optoelectronic properties. They can be widely used in biomedical imaging, photon catalysis, photosensitive materials, photocatalysis, anti-counterfeiting and other fields.

Organic quantum dots: Organic quantum dots are artificial quantum dots composed of organic materials. They are usually prepared by small molecule organic compounds through methods such as flue gas cracking. Organic quantum dots have the characteristics of narrow fluorescence spectrum, short luminescence lifetime, and high fluorescence quantum yield. Its excellent electronic transmission properties and excellent fluorescence performance can be applied in fields such as optoelectronic devices, biomedical imaging and drug delivery, and dye sensitized solar cells.