Optical properties and applications of two-dimensional CdSe nanoplatelets

Compared with zero-dimensional quantum dots and one-dimensional nanorods, two-dimensional nanoplatelets exhibit many unique optical properties. Due to strong quantum confinement in only one direction and the large lateral size, the CdSe nanoplatelets show large exciton binding energy, giant oscillator strength, narrow emission, large absorption cross-section, and large optical gain. In this review, the development of synthesis technology of nanoplatelets is first briefly introduced. Subsequently, the optical properties of CdSe nanoplatelets and their heterostructures are reviewed, including absorption and photoluminescence, carrier dynamics, optical gain, and nonlinear properties. These optical properties are affected by size, material and structure. At last, the main applications of CdSe nanoplatelets in recent years are introduced, including light-emitting diodes, lasers, light harvesting, photocatalysis, and sensing.