Quantum dots (QDs) are semiconductor luminescent nanocrystals. These nanomaterials are made of a crystal core surrounded by one or more different protective shells and a passivating layer. Their nano dimensions enable peculiar behavior that is completely different compared to the correspondent bulk materials.
In fact, these materials, when energy is provided, show remarkably high efficient and size-tunable induced photoluminescence over a wide-range of colors.
So, with the same material, it is possible to obtain different colors in the visible range and also in the near infrared region for a wide range of applications.