Recent Advances and Perspectives on Colloidal Semiconductor Nanoplatelets for Optoelectronic Applications

The strategy of a new generation of light-harvesting systems based on two-dimensional (2D) colloidal semiconductor nanoplatelets (NPLs) is an emerging field of research owing to the strong confinement in one direction, narrow emission, large exciton binding energy, and large absorption cross-section. In this Perspective, we provide fundamental insights into the ultrafast dynamics and luminescent properties of 2D semiconductor NPLs and their heterostructures. The variation of hot carrier cooling dynamics with changing the thickness of monolayers of CdSe NPLs is evident. Slow exciton recombination of 2D NPLs is reported in the presence of electron and hole acceptor molecules, indicating efficient charge separation which eventually controls the device performance. We envision the possibility of designing 2D NPLs heterostructures in combination with metal clusters, perovskite nanocrystals, and graphene oxide for photodetector, light-emitting diodes, photocatalysis, electroluminescence, and photovoltaics applications by controlling their charge transfer dynamics. The future perspective of this research field with promising areas is discussed.